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Weekend Course

### Deep Learning: Everything You Want to Know: Part 1

 N01 Saturday 8:00 - 9:30 Moderators: Dong Liang & Joshua Trzasko

 8:00 What Exactly Is Deep Learning? Bradley Erickson Deep learning has captured much attention because in many image recognition tasks, it surpasses human performance. The potential for this technology in radiology is substantial, and this talk will describe some of the areas in which deep learning has been or soon will be applied to improve radiological practice.

 8:30 Nuts & Bolts: How Does DL Work? Thomas Pock In this talk I will highlight connections between recent deep neural networks and classical methods for solving inverse problems in computer vision and image processing. I will focus on variational methods, graphical models which are known to be extremely flexible and also come along with a deep theoretical understanding. It turns out that many iterative algorithms for solving variational and graphical models can be unrolled and hence interpreted as layers in a deep neural network. The structure provided by these methods helps in reducing the number of model parameters and hence are less prone to overfitting. Moreover, the structure helps in interpreting the learned model parameters. I will show applications to stereo, motion and image reconstruction.

 9:00 Limitations & Caveats of Deep Learning Jeffrey Fessler This presentation will describe data-driven methods for image reconstruction, including adaptive dictionaries, sparsifying transforms, convolutional neural network (CNN) models, and deep learning techniques. It will also discuss limitations and challenges of such methods.

 9:30 Break & Meet the Teachers

Weekend Course

### Physics for Physicists: Part 1

Organizers: Matthias Günther, Herbert Köstler

 N02 Saturday 8:00 - 9:40 Moderators: Michael Steckner & Susann Boretius

 8:00 MRI: The Classical Description Adrienne Campbell-Washburn This lecture will cover the basics of MRI physics and image formation using the classical description. It will describe the basic concepts in magnetic moments, net magnetization of tissue and precession, as well as the manipulation of magnetization using RF pulses and magnetic field gradients to generate an image. Spin echoes and gradient echoes will be described along with the basics of T1 and T2 relaxation and their effect on image contrast. The Bloch equations will be used to summarize the evolution of magnetization and pulse sequence diagrams will be introduced to describe image formation.

 8:25 MRI: A Systems Overview Ralf Loeffler MRI systems consist of 3 main components plus computer systems for user interaction, measurement control and signal processing. The 3 components are dedicated to static and gradient magnetic field generation, as well as the RF system for RF transmission and reception. While the purpose of the components has not changed over time, actual implementation has due to technological advances as well as demands by new MRI techniques. This talk will present the basic designs for the different components and discuss current implementations and potential future developments.

 8:50 Bioeffects & Hazards from Static Field, Gradient, & RF Exposures Johan van den Brink This talk provides an overview of the MR safety risks and its scientific background

 9:15 T1- & T2-Contrasts & Their Molecular Origin Siegfried Stapf This tutorial aims at introducing the molecular mechanisms behind the relaxation times, and possible pitfalls in their experimental determination. The focus of the contribution is on the field-dependence of relaxation times, the importance of parasitic effects, and on addressing non-exponential signal behavior in a quantitative manner.

 9:40 Break & Meet the Teachers

Weekend Course

### Introduction to fMRI: Basics & Applications: Part 1

Organizers: Richard Buxton, Benedikt Poser, Joshua Shimony

 N03 Saturday 8:00 - 9:40 Moderators: Jonathan Polimeni & Joshua Shimony

 8:00 BOLD Signal Physiology Nicholas Blockley To understand the strengths and limitations of functional MRI we must understand the interaction between the physiology of the brain and the physics of the measured signal. In this talk I will introduce the major physiological drivers of the Blood Oxygenation Level Dependent (BOLD) effect and describe how they affect the MRI signal. We can then use this knowledge to consider how stimulus evoked changes in the BOLD signal can be quantified as changes in oxygen metabolism. Whilst the BOLD signal is considered to be complex, through this understanding, we can observe it provides a rich source of physiological information.

 8:25 Practical BOLD Acquisition Consideration Kevin Murphy In this educational course, we will explain basic BOLD scanning parameters; what they mean and how they interact with each other. We will discuss ways to improve BOLD time series quality using external recordings of physiology. Finally, we will touch on complementary MRI sequences that can further denoise BOLD fMRI time series.

 8:50 Basic Analysis of Task-Based fMRI Susan Francis The general linear model (GLM) is one of the most commonly used methods to analyse task-based fMRI data. This talk outlines the basic concepts of the GLM, how it is used to study block and event-related paradigms and associated statistical analysis, as well as some example applications. The talk will then describe some limitations of a GLM, and briefly outline alternative methods to study task-based fMRI paradigms, such as the phase-encoding or travelling-wave method, and independent component analysis.

 9:15 Introduction: Resting-State Functional Connectivity Jonathan Power "Functional connectivity" or "resting state" MRI has become commonplace in neuroscience over the last decade, and is increasingly used for clinical studies. This talk introduces some of the central concepts and findings in resting state fMRI. Earlier talks will cover fMRI data acquisition, this talk will mainly discuss data analysis and interpretation. This talk will open by introducing a convenient way to visualize fMRI scans, and then will use this approach to visually fractionate resting state fMRI data (via multi-echo analyses) into non-BOLD and BOLD signals. Only BOLD signals are typically thought to be of interest, but both kinds of signals are prevalent in fMRI scans, and both kinds of signals correlate with cognitive and behavioral variables of interest, making it important to recognize the signatures of each kind of signal. We will discuss the spatial and temporal manifestations of these signals and illustrate how these signals influence functional connectivity properties. We will illustrate how individual denoising techniques remove particular kinds of signals, and that no single denoising technique removes all unwanted signals from a dataset. Effective denoising requires multiple simultaneous approaches to best isolate BOLD signals of interest.

 9:40 Break & Meet the Teachers

Weekend Course

### MR Systems Engineering: Part 1

Organizers: Gregor Adriany, Christoph Juchem, Mary McDougall, Greig Scott

 N04 Saturday 8:00 - 9:30 Moderators: Christoph Juchem & Sebastian Littin

 8:00 MR Systems Overview Hubertus Fischer This educational talk provides a comprehensive overview on the building blocks of a clinical MR system. It concentrates on the essential functions to generate and to detect an MR signal, and how to achieve spatial resolution. It provides short look into the field generating unit, the RF transmit and receive system as well as the real time control unit. These topics outlined briefly as it is covered in detailed lectures of this session. The MR Systems overview is completed by covering the patient interface (patient table, communication and physiological triggering) and support functions as cooling, component supervision and RF shielding.

 8:30 Magnets: Design, Manufacturing, Installation, Present & Future Technology Ben Parkinson This is an educational presentation to give ISMRM participants an understanding of the design and manufacturing processes required to produce a typical MRI magnet.  The presentation explains the background to the magnetic field requirements for MRI and, using a worked example, explains typical MRI magnet design and the constraints under which that design occurs.  In addition to the electromagnetic design, focus is placed on different cryogenic solutions for MRI magnets, and practical implementation of magnet design aspects.

 9:00 Shimming: Superconducting & Passive Shims; Higher-Order Shims, Shim Arrays & Dynamic Shimming Vincent Boer Magnetic resonance imaging (MRI) and spectroscopy (MRS) rely on a strong and highly homogeneous magnetic field inside the scanner. Although magnets have a highly sophisticated design, there are still several techniques used to homogenize the field. Secondly, all biological samples will induce (dynamic) distortion in the field due to the tissue magnetic susceptibility. In this part of the course both passive shimming of a magnet, as well as active shimming with a subject in the magnet, will be discussed. Furthermore, several new advanced shimming strategies have emerged recently, some of the most promising ones will be discussed.

 9:30 Break & Meet the Teachers

Weekend Course

### Advanced Clinical MR Imaging in MSK: Part 1

Organizers: Eric Chang, Garry Gold, Emily McWalter, Edwin Oei, Philip Robinson

 S01 Saturday 8:00 - 9:30 Moderators: Paolo Felisaz & Matthew Koff

 8:00 Rapid MR (3D, CS, Machine Learning) Garry Gold This presentation will cover new methods for rapid three-dimensional musculoskeletal imaging, including compressed sensing and machine learning methods.

 8:30 Shoulder Luis Beltran This presentation will discuss imaging of the shoulder with an emphasis on operative management of anterior shoulder instability and rotator cuff tears.  The learning objectives are to a) understand the mechanisms of injury and associated pathologies in anterior shoulder instability and rotator cuff tears, b) be familiar with current treatment guidelines for management of anterior shoulder instability and rotator cuff disease, c) recognize the normal and abnormal appearances of postoperative MRI studies for anterior shoulder instability surgery and rotator cuff repairs.   I give permission to record this presentation.

 9:00 Advanced Imaging in Hand & Wrist in Common Rheumatologically & Traumatic Conditions Mikael Boesen The lecture will show the conventional ways of imaging most common rheumatically and traumatic conditions in the hand and wrist and show the potential added value of new 3-dimensional and multi-parametric imaging technologies like dynamic contrast enhanced MRI (DCE-MRI), PET-CT and PET MRI, ultrasound, dual energy- and conebeam CT of the hand and wrist as promising methods to complement the imaging portfolio that adds further to the understanding and quantification of the pathophysiology, inflammatory load and morphological disease patterns in patients with rheumatoid arthritis (RA), psoriasis arthritis (PsA), crystal deposition diseases (Urate and CPPD), osteoarthritis (OA) and trauma.

 9:30 Break & Meet the Teachers

Weekend Course

### Body MRI: Realities & Controversies: Expanding the MRI Clinical Frontier

Organizers: Kathryn Fowler, Kartik Jhaveri, Lorenzo Mannelli, Valeria Panebianco, Scott Reeder, Reiko Woodhams

 S02 Saturday 8:00 - 9:30 Moderators: Dow-Mu Koh & Mark Schiebler

 8:00 Current State of the Art Hersh Chandarana Abdominal or Body MRI suffers from number of limitations such as (1) slow and inefficient acquisition (2) sensitivity to motion related artifacts and (3) limited volumetric coverage and spatial resolution which are constrained by the breath-hold capacity of the patients. Various methods are used clinically and are being investigated to overcome these limitations in order to permit motion robust and rapid imaging of the abdomen. This talk will briefly discuss some of these methods for (1) fast imaging and (2) motion compensated imaging of the abdomen.

 8:22 Non-Vascular Thoracic MRI Constantine Raptis Despite advances in imaging unit technology and research in the field, the utilization of thoracic MRI in regular clinical practice for noncardiac and nonangiographic applications has lagged behind expectations. While there are several clinical scenarios in which nonvascular thoracic MRI has a potential primary role, it is at present most frequently utilized as a problem solving modality to answer specific questions that cannot be determined via other imaging modalities, most commonly CT. The purpose of this talk is to explore commonly encountered situations in which thoracic MRI can be utilized to its fullest extent as a problem solving modality.

 8:44 Body MR in ED Bobby Kalb Magnetic resonance imaging is increasingly being used in the emergency department setting, and offers potential advantages related to safety, diagnostic accuracy and efficiency, compared to the more commonly utilized modalities of CT and ultrasound. This presentation will describe methods for advantages of performing MRI in the ED for acute abdominopelvic pain and also PE, in addition to detailing suggested imaging protocols and techniques.

 9:06 Whole-Body Imaging Taro Takahara

 9:30 Break & Meet the Teachers

Weekend Course

### Analyzing the Brain: New Paradigms: Part 1

 S03 Saturday 8:00 - 9:30 Moderators: Qiyong Gong & Kei Yamada

 8:00 Optimizing Acquisition for Robust MR Data James Pipe

 8:22 Standardization Challenges: Multi-Site Thomas Chenevert

 8:44 Population-Based Neuroimaging for Disease Etiology & Prediction Meike Vernooij Many neurological diseases, especially those occurring at older age, have a long subclinical phase during which a person is asymptomatic and does not seek medical attention. As a consequence, once symptoms manifest, in many instances the pathologic changes caused by the disease process are already advanced and mostly irreversible. To study disease in the asymptomatic stage, population-based studies are of great importance. Medical imaging applied in these studies, or ‘population imaging’ can, non- or minimally-invasively, show the changes that occur in the human body that may reflect either early disease, intermediate factors or risk indicators of disease.

 9:06 Automatic Segmentation Susumu Mori In this presentation, the basic concept of anatomical segmentation is explained. This presentation first discusses about the importance of tissue segmentation for modern medical data analysis, in which difficult neurological conditions are often the target of the research. Then different types of segmentation approaches are explained. In the last section, an interesting paradox of the tissue segmentation, namely the lack of ground truth, is discussed in detail. This presentation should be informative for both method developers and users.

 9:28 Break & Meet the Teachers

Weekend Course

### Molecular Imaging for Beginners: Part 1

Organizers: Ichio Aoki, Arvind Pathak

 S04 Saturday 8:00 - 9:15 Moderators: Christin Sander & Arvind Pathak

 8:00 Introduction to MR Molecular Imaging Peter Caravan

 8:25 Multimodality Molecular Imaging for Beginners Kristine Glunde Multimodality molecular imaging applies imaging modalities beyond visualizing anatomy and morphology to include the ability of imaging disease-specific biomolecules and pathways in cancer, cardiovascular disease, and inflammation, among others. Imaging modalities used in molecular imaging are computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance spectroscopic imaging (MRSI), optical imaging, positron emission tomography (PET), single-photon-emission computerized tomography (SPECT), and ultrasound (US). This lecture will give an overview of the most important concepts and applications in multimodality molecular imaging for beginners.

 8:50 Fundamentals of MR Relaxation for Molecular Imagers Silvio Aime

 9:15 Break & Meet the Teachers

Weekend Course

### Deep Learning: Everything You Want to Know: Part 2

 N01 Saturday 10:00 - 11:30 Moderators: Dong Liang & Joshua Trzasko

 10:00 Applications: Image Acquisition & Reconstruction Leslie Ying Deep learning, as a powerful tool for artificial intelligence, has attracted a lot of attention in the MRI community. Recently deep learning has shown success in image acquisition and reconstruction. It has demonstrated some unique benefits over the existing methods. This course will teach how to use deep learning to perform image reconstruction from acquired k-space data.

 10:30 Applications: Image Processing, Analysis & Interpretation Daniel Rueckert We will give an overview of the current state-of-the-art in deep learning for medical imaging applications such as segmentation and classification. In particular We will illustrate deep learning approaches for semantic image segmentation based on Convolutional Neural Networks (CNN). We will also show how adversarial approaches can be used to train CNNs that invariant to differences in the input data (e. g. different scanners and imaging protocols), and which does not require any labelled data for the test domain. Finally, we show some applications of CNNs in the context of image classification.

 11:00 How to Jump-Start Your Deep Learning Research Florian Knoll This talk will provide a practical hands-on overview of how to get started in machine learning research from the point of view of an imaging lab. Common hurdles and pitfalls will be discussed via didactic examples from classification and reconstruction. The key differences of medical imaging data and computer vision applications will be highlighted. The talk will also discuss software frameworks and implementation, including code demos, which will be made available as open source.

 11:30 Adjournment & Meet the Teachers

Weekend Course

### Physics for Physicists: Part 2

Organizers: Matthias Günther, Herbert Köstler

 N02 Saturday 10:00 - 11:15 Moderators: Susann Boretius & Michael Steckner

 10:00 Spatial Encoding (Introduction to k-Space, MRI as a Linear & Stationary System, PSF, MTF, Nyquist) Tobias Wech This presentation will provide an introduction to the k-space formalism. MRI will be approximated as a linear and stationary system and the point spread function as well as the modulation transfer function will be introduced as descriptive tools. Finally, the sampling-theorem of Nyquist and Shannon will be discussed with respect to classical MRI and newer techniques like compressed sensing or MR-fingerprinting.

 10:25 How to Get the Optimal Signal-to-Noise Claudia Hillenbrand Acquiring an optimal image for clinical applications often means to strike the right balance between resolution, scan time, and signal to noise (SNR) in order to achieve the desired imaging objectives.  The SNR is a fundamental measure of quality and performance in MRI. This presentation will review the basic principles relevant to signal and noise, measurement of SNR, factors influencing SNR, and discuss techniques that attempt to optimize SNR.

 10:50 More than One RF-Pulse: Echoes & Phase Graphs Matthias Weigel The basic ideas and the resulting potential of the Extended Phase Graph (EPG) concept are described. It represents an elegant means for the pictorial and quantitative depiction of the resulting magnetization response in multi pulse sequences. EPGs also aid in the understanding and classification of echo generation. Based on these powerful properties and possibilities, the EPG concept has got a lot of attention during the last years. Additionally, the syllabus provides a collection of known and less known references.

 11:15 Lunch & Meet the Teachers

Weekend Course

### Introduction to fMRI: Basics & Applications: Part 2

Organizers: Richard Buxton, Benedikt Poser, Joshua Shimony

 N03 Saturday 10:00 - 11:40 Moderators: Jonathan Polimeni & Joshua Shimony

 10:00 Clinical fMRI: Presurgical Mapping Alberto Bizzi

 10:25 Clinical fMRI: Psychiatric Applications Xiaoqi (Juliana) Huang Psychiatric disorders traditionally have been classified as broad syndromes defined by symptoms rather than underlying neurobiologic substrate. The ability to visualize and quantify brain function, in vivo, noninvasively, is particularly important for psychiatric disorders. Recently, BOLD-fMRI has been widely used to identify brain functional or physiologic abnormalities in patients with psychiatric disorders. This lecture will introduce how the BOLD-fMRI can help us know more about psychiatric disorders in terms of mechanism, prediction and classification. This understanding will lay a foundation for building imaging biomarkers for psychiatric disorders.

 10:50 ASL techniques for perfusion and/or BOLD imaging Dimo Ivanov Arterial spin labeling (ASL) enables non-invasive, quantitative MRI measurements of tissue perfusion, and has a broad range of applications including functional brain imaging. ASL can concurrently measure perfusion and blood oxygenation level dependent (BOLD) signal changes, which proves useful for investigating the brain’s physiology in health and disease. However, ASL suffers from limited temporal resolution and has a lower signal-to-noise ratio (SNR) compared to conventional BOLD imaging. In this lecture, the functioning, advantages, disadvantages and application areas of ASL will be summarized. Furthermore, the acquisition approaches and imaging parameters that influence ASL’s SNR and temporal resolution will be reviewed.

 11:15 BOLD & EEG/MEG Rene Scheeringa Electrophysiological and hemodynamic measures are the two most prominent tools to study brain function non-invasively in humans. The two methodological approaches are thought to provide complementary information on how the brain functions. For this it is important to understand how these two methodologies are related. In this lecture I will mainly focus on how neural oscillations relate to BOLD/fMRI. I will explore how neural oscillations recorded both invasively, and with MEG and EEG relate to the BOLD signal and present my own work that relates neural oscillations to laminar specific changes in the BOLD signal and fMRI-based connectivity.

 11:40 Adjournment & Meet the Teachers

Weekend Course

### MR Systems Engineering: Part 2

Organizers: Gregor Adriany, Christoph Juchem, Mary McDougall, Greig Scott

 N04 Saturday 10:00 - 11:30 Moderators: Christoph Juchem & Sebastian Littin

 10:00 Gradient Coil Design Considerations, Manufacturing & Limitations Richard Bowtell Magnetic resonance imaging relies on the use of magnetic field gradients – that is a magnetic field, B (r) which varies linearly withposition, r, such that B (r) = G.r – to spatially encode the NMR signal. Such gradients are generated by passing currents throughspecially arranged coils of wire, placed on a former that surrounds the imaging subject. Three separate coils are needed in order toproduce a linear variation of the z-component of the magnetic field along each of the three Cartesian directions (x, y and z). Theperformance of the gradient coils and the amplifiers that are used to drive them dictates the kind of gradient waveforms that can beused in an MR scanner, particularly controlling the maximum gradient strength and rate of change of gradient with time that can be employed. Since the use of strong and rapidly switched gradients generally improves image quality and the speed of imagea cquisition, considerable benefits can result from optimising gradient coil performance.

 10:30 Gradient Drivers: Amplifier Considerations, Power, Tuning & Cooling Juan Sabate Improvements in magnetic resonance imaging (MRI) require increased performance of the gradient amplifier. The objective of the presentation is to provide a description of the gradient amplifier functionality as part of the gradient system and to explain the design of the amplifier to meet the MRI requirements. PSDs reproduction fidelity and power needed for gradient fields requires switched amplifiers. The fidelity is achieved using digital control with high control bandwidth, feedforward and adequate compensations. New SiC semiconductors reduce losses keeping high performance and reducing volume and cost. The presentation provides detailed description of high-performance amplifier implementation and test results.

 11:00 Eddy Currents & Interactions: Characterization & Compensation S. Johanna Vannesjo Magnetic resonance imaging relies on the ability to produce spatially linear magnetic fields (i.e. gradient fields) with a defined temporal evolution. This is achieved with room-temperature gradient coils, through which time-varying currents are passed. The resulting change in magnetic field will however induce eddy currents in nearby conducting structures according to Faraday’s Law of induction. This distorts the time-course of the gradient fields, leading to artefacts in imaging and spectroscopy. This presentation will give an overview of how eddy currents are generated, how to characterize them and how to compensate for their effects on the field.

 11:30 Lunch & Meet the Teachers

Weekend Course

### Advanced Clinical MR Imaging in MSK: Part 2

Organizers: Jenny Bencardino, Eric Chang, Garry Gold, Emily McWalter, Edwin Oei, Philip Robinson

 S01 Saturday 10:00 - 11:30 Moderators: Paolo Felisaz & Matthew Koff

 10:00 Peripheral Nerves Zehava Rosenberg This talk will focus on MR imaging of peripheral nerve of the knee, ankle and foot.    The talk will be subdivided into two parts.  A.  A discussion of general MRI features of entrapment neuropathies in the lower extremity.  The listener will be provided with distinctive direct and indirect features of neuropathy.  B.  Focused discussion of specific nerves commonly susceptible to neuropathy, with a brief initial review of normal anatomy followed by MRI examples of common neuropathies.

 10:30 Imaging Around Metal (Physics) Kevin Koch

 11:00 Hip Andoni Toms

 11:30 Lunch & Meet the Teachers

Weekend Course

### Body MRI: Realities & Controversies: Liver Imaging

Organizers: Kathryn Fowler, Kartik Jhaveri, Lorenzo Mannelli, Valeria Panebianco, Scott Reeder, Reiko Woodhams

 S02 Saturday 10:00 - 11:30 Moderators: Shetal Shah & Bachir Taouli

 10:00 MRI Diffuse Liver Disease Shahid Hussain

 10:22 Imaging of the Portal Venous System Reena Jha Radiologists commonly encounter portal venous abnormalities. Understanding the varying appearances of acute and chronic portal venous thromboses and the associated changes of hepatic enhancement patterns is important for patient management. Furthermore, it is important to recognize that portal venous thrombosis may change the contour of the liver, and simulate cirrhosis. Congenital and acquired chronic portal vein thrombosis may lead to the development of hepatic masses, and may alter the appearance of the bile ducts and mimic malignancy.

 10:44 Liver Lesions: Malignant Thomas Vogl In summary, liver imaging has found its place in the reality of cross-sectional imaging. The use of contrast agent is still controversial. Here further developments are directed in order to improve the qualitative and quantitative information. Artificial intelligence techniques will integrate multiparametric MRI information in the concept of radionics and radiogenomics.

 11:06 Biliary Imaging & Pathology Mi-Suk Park In this talk, I will present differential diagnosis of biliary lesions based on imaging phenotypes with pathologic correlation. And then TNM staging with pathologic correlation will be reviewed based on the 8th edition of NCCN guidelines.

 11:28 Lunch & Meet the Teachers

Weekend Course

### Analyzing the Brain: New Paradigms: Part 2

 S03 Saturday 10:00 - 11:30 Moderators: Qiyong Gong & Kei Yamada

 10:00 Lesion Detection (MS, Vascular Lesions) Shingo Kakeda The role of brain MRI in diagnosis of multiple sclerosis (MS) and vascular lesions is well established, and the recently developed MR techniques, including synthetic MRI, myelin map with q-Space diffusion MRI, susceptibility-weighted imaging (SWI) and quantitative susceptibility mapping (QSM), further improve the diagnostic value in a research and clinical routine setting. This course will introduce the recent data pertaining to the use of new MR techniques in assessing MS lesion and small vascular lesions (cerebral microinfarcts).

 10:22 Graph-Theory Brain Network Analysis Yong He

 10:44 Adversarial generative network - new generation of image generation Masayuki Ohzeki We introduce a concept of the generative adversarial network and consider its possibility of medical application.

 11:06 Machine Learning II (For Medicine) Bradley Erickson This session will describe the basic concepts of machine learning, both traditional machine learning and deep learning. Particular emphasis will be placed on how ML methods can give results that appear good, but may not be correct or representative of real world performance.

 11:28 Adjournment & Meet the Teachers

Weekend Course

### Molecular Imaging for Beginners: Part 2

Organizers: Ichio Aoki, Arvind Pathak

 S04 Saturday 10:00 - 11:40 Moderators: Christin Sander & Arvind Pathak

 10:00 MR Spectroscopy - The Forgotten Molecular Imaging Modality Robin de Graaf MR-based molecular imaging typically relies on the high detection sensitivity of water to indirectly observe the underlying molecular and cellular processes. The ubiquitous presence of water demands that image contrast and specificity is obtained through molecular imaging probe design. MR spectroscopy uses the intrinsic specificity provided by the chemical shift to allow detection of a wide range of metabolites and metabolic pathways. When combined with spatial imaging gradients, MR-based metabolic imaging can provide a unique and complementary addition to the arsenal of molecular imaging techniques.

 10:25 Principles of Probe Design for Molecular Imagers Horacio Cabral Molecular imaging allows the visualization of biological events in real-time at tissue, cellular and subcellular levels in living systems by merging conventional imaging techniques with probes designed to report the expression of biomarkers or variations in physiological factors. Successful molecular imaging agents should provide high contrast intensity with low noise-to-signal ratio at the target in vivo for sufficient time. Herein, I recapitulate the principles for designing effective molecular imaging probes for various imaging modalities, and provide fundamental strategies for the development of these probes and their application in biology, diagnosis and therapy.

 10:50 Introduction to "Cellular" Molecular Imaging Ben Bartelle

 11:15 How to Design a Molecular Imaging Experiment Emmanuel Barbier This course will address the steps that a beginner should follow to develop a molecular imaging experiment in small animals: after setting the target and choosing the appropriate animal model, we will evaluate the pros and cons of existing imaging modalities, with a focus on MRI data acquisition and integration during post-processing. Examples will be taken from oncology and neuroscience.

 11:40 Adjournment & Meet the Teachers

Weekend Course

### Statistical Analysis for Imaging Studies: Part 1

Organizers: Jennifer Keegan, Dwight Nishimura

 N01 Saturday 13:15 - 14:45 Moderators: Jayashree Kalpathy-Cramer & Jennifer Keegan

 13:15 Designing Studies of Diagnostic Imaging Susan Mallett

 13:40 Basic Concepts in Measurement Error Alice Sitch

 14:05 Break & Meet the Teachers

 14:20 Study Designs and Bias TBD

 14:45 Monitoring Studies Alice Sitch

 15:10 Break & Meet the Teachers

Weekend Course

### Physics for Physicists: Part 3

Organizers: Matthias Günther, Herbert Köstler

 N02 Saturday 13:15 - 14:55 Moderators: Patricia Figueiredo & Maxim Zaitsev

 13:15 Spin Echo, RARE, GRASE Jürgen Schneider Starting from the basic spin-echo sequence, this talk will subsequently introduce more advanced imaging sequence, which are based on multiple refocusing pulses. Advantages and technical challenges for these sequences will be discussed, and example applications will be given.

 13:40 Gradient Echo Sequences Oliver Bieri The fundamental signal generation in magnetic resonance imaging (MRI) sequences is based on the principle of either spin echoes or gradient echoes or a combination of the two. This course elucidates concepts and basic properties of gradient echo methods with a special focus on fast gradient echo sequences.

 14:05 Basic Preparation of Image Contrast Ute Goerke The lecture covers the basic principles of the molecular origin of image contrast, how the choice of sequence type and imaging parameters influence contrast and the implementation of additional sequence components to create a specific image contrast. The theory behind the presented concepts will be discussed and illustrated with examples from relevant applications.

 14:30 RF Pulse Design Markus Barth This course part will cover the concepts to understand the theory and implementation of radiofrequency (RF) pulses including the small tip angle tip angle approximation, the Shinnar-LeRoux (SLR) algorithm and numerical methods.

 14:55 Break & Meet the Teachers

Weekend Course

### Advanced fMRI: Connectivity & Cutting Edge: Part 1

Organizers: Richard Buxton, Benedikt Poser, Joshua Shimony

 N03 Saturday 13:15 - 14:30 Moderators: Shella Keilholz & Benedikt Poser

 13:15 Connectivity: Analysis Mark Lowe An overview of current analysis methods for assessing functional connectivity using resting state fMRI data. A brief review of important preprocessing steps necessary for quality resting state data as well as various complex network analysis methods, including structural equation modeling, clustering methods and graph theoretic methods. Dynamic functional connectivity methods are briefly discussed.

 13:40 A Multi-modal Parcellation of Human Cerebral Cortex Matthew Glasser We will discuss the Human Connectome Project’s multi-modal cortical parcellation version 1.0—the data acquisition and analysis requirements, how the parcellation was made, and how it can be applied to individuals.  This state of the art map of the cerebral cortex was made possible by using exceptionally high quality MRI data precisely aligned across individuals.  Cortical areal boundaries were identified when visible in multiple modalities and areas were painstakingly related to the neuroanatomical literature.  A machine learning classifier was then trained to automatically identify each cortical area based on its multi-modal fingerprint in individual subjects, replicating the parcellation.

 14:05 fMRI Connectivity, Depression, and Anhedonia: a Bayesian network analyses in Schizophrenia, Bipolar Disorder, ADHD, and Healthy Controls Ariana Anderson Although MRI, fMRI, and genetic biomarkers have been implicated in depression, it is unclear how much these measures illuminate the disorder compared to behavioral and demographic measurements.  Using these measurements, we predicted depressive symptoms to compare the effect size of these modalities.  In 119 subjects with a diagnosis of Bipolar disorder (n=43), Schizophrenia (n=39), and ADHD (n= 37), random forests models predicted both generalized depression (Hopkin Symptom Checklist) and anhedonia-specific measures (Chapman Scales for Physical and Social Anhedonia) using genetic, structural MRI volumetric measures, resting-state fMRI network connectivity measures, demographic features, and behavioral assessments measures. We found that comorbid behavioral symptoms accounted for nearly 75% of predictive ability.  When removing behavioral assessments, only 8.75% of variance in the depression symptom scores were predictable from neuroimaging, demographic, genetic measures.  Demographics retained the strongest predictive ability.

 14:30 Break & Meet the Teachers

Weekend Course

### MR Systems Engineering: Part 3

Organizers: Gregor Adriany, Christoph Juchem, Mary McDougall, Greig Scott

 N04 Saturday 13:15 - 14:45 Moderators: Christoph Juchem & Sebastian Littin

 13:15 RF Transmit: Power Delivery, Decoupling & Duty Cycle Natalia Gudino This talk will cover different RF engineering methods used in the design and implementation of transmit systems currently available in clinical MRI settings and research sites.

 13:45 RF Receivers: Signal Detection Chain, Digitization, System Noise Figures - from MRI Signal to Bits Nicola De Zanche This lecture covers the components of the RF chain from detection of the signal in the RF coil to its final representation as digital data. Each component is described and its effect on signal strength and quality is discussed.

 14:15 Controlling the MR Subsystems: Pulse Sequence Control, Waveform Generation & Real-Time Control Juan Santos Lecture for scientists and clinicians interested in learning more details about the core software structure and control systems of an MRI machine.

 14:45 Break & Meet the Teachers

Weekend Course

### Advanced Clinical MR Imaging in MSK: Part 3

Organizers: Eric Chang, Garry Gold, Emily McWalter, Edwin Oei, Philip Robinson

 S01 Saturday 13:15 - 14:45 Moderators: Emily McWalter & Alissa Burge

 13:15 Knee Jung-Ah Choi The purpose of lecture is to review and apply current and emerging techniques in MR imaging of the knee joint.

 14:15 Body composition, Lipid & Fat Imaging Martin Torriani Body composition can be assessed using multiple imaging modalities, such as CT, MRI, MRS and PET, and provide valuable information in conditions associated with abnormal lipid distribution.

 14:45 Break & Meet the Teachers

Weekend Course

### Body MRI: Realities & Controversies: Other GI Imaging

Organizers: Kathryn Fowler, Kartik Jhaveri, Lorenzo Mannelli, Valeria Panebianco, Scott Reeder, Reiko Woodhams

 S02 Saturday 13:15 - 14:45 Moderators: Jeffrey Brown & Naranamangalam Jagannathan

 13:15 DWI for the Pancreas Yashihiko Fukukara DWI reflects changes in water mobility caused by interactions with cell membranes, macromolecules, and alterations to the tissue environment. It enables quantitative assessment of tissue diffusivity based on the apparent diffusion coefficient. Advances in image quality have made DWI a routinely implemented clinical protocol for the pancreas, as it can be performed relatively quickly and has excellent contrast resolution without the administration of contrast agents. DWI is a promising technique for the evaluation of pancreas tumors, including detection, characterization, monitoring treatment response, and prediction of patient prognosis. Its role in the above mentioned clinical settings will be discussed.

 13:37 MR Enterography Jordi Rimola In this lecture we are going to discuss the key signs for detecting and grading active inflammation and characterizing complications, in particular strictures. We also highlight the current limitations of the technique and potential ways to overcome them.

 13:59 MRI of Perianal Fistula Ellie Korngold

 14:21 Advances in Abdominal Imaging Shreyas Vasanawala

 14:45 Break & Meet the Teachers

Weekend Course

### MR for Neuropsychiatric Disorders: Part 1

Organizers: Qiyong Gong, John Port

 S03 Saturday 13:15 - 14:45 Moderators: Qiyong Gong

 13:15 Overview of MR Brain Methods Kelvin Lim Magnetic resonance has the advantage of having multiple acquisition methods and parameters that result in the collection of different types of information.  This capability to collect multimodality information has made MR a critical tool for the study of neuropsychiatric disorders. This presentation will provide an overview of the multiple modalities available with MR.  Part 1 will provide an intuitive conceptual framework for comparing and contrasting the different modalities available with MR. in Part 2, we will use this framework to compare and contrast the major MR modalities, focussing on the following categories of information: Anatomy, Diffusion, Function and Spectroscopy.

 13:45 MR of Aging and Dementia Prashanthi Vemuri Universally observed cognitive decline in the elderly due to the pathological aging of the brain will have a significant impact on public health. This presentation will aid in understanding 1) the recent advances in the field of aging and dementia; 2) MR methodologies that are used for the evaluation of age and dementia related brain changes specifically due to Alzheimer’s disease pathophysiology and cerebrovascular disease as tools for diagnosis, prognosis, measuring disease progression, and mechanistic inferences into the disease process in cognitive aging and dementia; and 3) open questions and directions in this research area for MR.

 14:15 MR of Depression/Bipolar Disorders Su Lui Depression is a heterogeneous condition. Some patients who meet symptom criteria for major depressive episode (MD) also identify with bipolar disorder (BD). Until now, there are no objective markers for differentiating MD and BD, and also for early diagnosis, risk evaluation and treatment options. We reviewed the MRI findings of structural and functional alternations in MD and BD at the time of premorbid, before treatment and after treatment with multi-modal MRI image data. The research above provided the possibility of diagnosis, finding out high-risk individuals before disease and predicting treatment effects by MRI.

 14:45 Break & Meet the Teachers

Weekend Course

### Novel Approaches in Molecular Imaging: Part 1

Organizers: Natalie Serkova, Damian Tyler

 S04 Saturday 13:15 - 14:45 Moderators: Natalie Serkova & Damian Tyler

 13:15 PET-MRI: The Technical Aspects TBD

 13:37 PET-MRI: The Application Andreas Kjaer

 13:59 Hyperpolarized 13C MRI: The Technical Aspects from Hamiltonian to Homo sapien Jack Miller We will examine the mechanistic details behind dissolution-Dynamic Nuclear Polarisation with small molecules for in vivo applications, and additionally discuss some of the technical challenges that arise in the design of pulse sequences to use the magnetisation that the technique generates.

 14:21 Hyperpolarized 13C MRI: The Application Jessica Bastiaansen

 14:43 Break & Meet the Teachers

Weekend Course

### Statistical Analysis for Imaging Studies: Part 2

Organizers: Jennifer Keegan, Dwight Nishimura

 N01 Saturday 15:15 - 16:30 Moderators: Jayashree Kalpathy-Cramer & Jennifer Keegan

 15:45 Advanced Methods & Reporting Susan Mallett

 16:15 Adjournment & Meet the Teachers

 16:45 Reporting Guidelines and Making Your Research Useful TBD

Weekend Course

### Physics for Physicists: Part 4

Organizers: Matthias Günther, Herbert Köstler

 N02 Saturday 15:15 - 16:30 Moderators: Patricia Figueiredo & Maxim Zaitsev

 15:15 Susceptibility, Flow, Chemical Shift, Motion Artifacts & Imaging Frederik Laun Following this lecture, the audience will understand the effect of magnetic susceptibility, flow, chemical shift, and motion on MRI. They will be able to use this knowledge to identify and minimize related artifacts or, alternatively, to measure the underlying effects.

 15:40 EPI as Workhorse for Diffusion, Perfusion, fMRI.... Penny Gowland Traditionally MRI is used to produce high quality, high resolution images of the human anatomy. However it is also has the capacity to capture a range of dynamic processes in the body, and one of the best imaging sequences for doing this is EPI. This talk will consider the advantages and disadvantages of EPI as a readout scheme, its use in quantitative imaging and in imaging dynamic processes.

 16:05 Arbitrary Trajectories: ACQ, Gradients, Reconstruction, Artifacts S. Johanna Vannesjo Cartesian k-space sampling on a regular grid provides optimal conditioning for image reconstruction. Yet, there are several reasons why it can be beneficial to deviate from the regular Cartesian sampling scheme. It may for example be to achieve faster coverage of k-space, to make use of self-navigating properties, to shape the point-spread function or to reduce the echo time. The most commonly used non-Cartesian acquisitions are radial and spiral sampling, but a large range of advanced sampling schemes have been explored. This presentation will cover basic considerations related to arbitrary sampling, from gradient waveform design to image reconstruction.

 16:30 Adjournment & Meet the Teachers

Weekend Course

### Advanced fMRI: Connectivity & Cutting Edge: Part 2

Organizers: Richard Buxton, Benedikt Poser, Joshua Shimony

 N03 Saturday 15:15 - 16:55 Moderators: Shella Keilholz & Benedikt Poser

 15:15 BOLD Acquisition Beyond 2D EPI Wietske van der Zwaag Although the vast majority of fMRI studies is still performed with 2D-EPI, there are several other BOLD-sensitive sequences, available on most clinical platforms, that may perform better. The main alternatives to 2D-EPI are 3D-EPI and SMS-EPI, although EVI, MR-encephalography, ME-EPI and SE-EPI have also recently gathered interest. All these sequences will be discussed and compared to one another in terms of their strengths, weaknesses and artifacts. Specific situations in which a specific sequence would be preferred will be used to highlight the relevant strong points.

 15:40 fMRI Acquisition Beyond BOLD J. Jean Chen Although the BOLD signal has been the workhorse of fMRI,  BOLD fMRI is limited by its intrinsic T2/T2* sensitivity and exhibits exaggerated weighting towards large veins. Moreover, the BOLD signal is a relative rather than quantitative measure of brain function that depends on the interplay of perfusion and oxygenation, leaving room for ambiguous interpretation. This talk will summarize recent efforts to explore alternative fMRI methods, including those based on blood flow, blood volume and blood oxygenation. The applications of these methods in both task-based and resting-state studies will be introduced.

 16:05 High Resolution Applications: Cortical Layers Jonathan Polimeni Laminar fMRI refers to the study of functional activation within the cerebral cortex, with the goal of detecting distinct functional activity within cortical layers, and is an emerging application of high-resolution fMRI. Although individual cortical layers cannot be resolved with current human fMRI techniques, and hemodynamic coupling and variation of fMRI signals across layers is incompletely understood, because of the roles cortical layers play in distributed neuronal processing measuring layer-specific activation is key to understanding brain circuitry, which motivates work towards surmounting these difficulties. This presentation will introduce laminar fMRI, summarize recent advances, and focus on challenges faced when interpreting these data.

 16:30 Combining fMRI with Advanced Neurotechniques Xin Yu By combining fMRI with fiber optic calcium recording and optogenetics, as well as two-photon microscopy or convetional optical imaging techniques, the circuit-specific regulatory mechanism of the unique neuro-glial-vascular (NGV) interaction model can be studied at varied brain states in animals. Combine fMRi with advanced neurotechniques provides very powerful methodological platforms to deepnen our understanding how enural circuits mediate specific behavioral outputs, as well as link the cellular mechaism and neural circuit regulation (causality) to the systems level correlation (e.g. fMRI) to behavioral index.

 16:55 Adjournment & Meet the Teachers

Weekend Course

### MR Systems Engineering: Part 4

Organizers: Gregor Adriany, Christoph Juchem, Mary McDougall, Greig Scott

 N04 Saturday 15:15 - 16:45 Moderators: Christoph Juchem & Sebastian Littin

 15:15 Multi-Modality Imaging in an MRI Scanner: Making the Systems Compatible Chrit Moonen Focused ultrasound (FUS) is increasingly used for therapy. It can be guided by MRI, ultrasound imaging, or both. Here, three examples are elaborated how MRI and ultrasound imaging can be used simultaneously and beneficially for guiding FUS: 1) Tracking of beampath obstructions (ribs); 2) Motion evaluation; 3) Monitoring of cavitation during drug delivery with microbubbles.

 15:45 Basic MR Safety: SAR to Temperature, Power Deposition/Monitoring, Effects of RF Coils & Field Strength Nicolas Boulant The advent of parallel transmission at high field has led to many studies aiming at quantifying more accurately the Specific Absorption Rate (SAR)/temperature aspects while understanding in more details the risks involved in MRI experiments. This talk gives a review of different techniques employed for SAR calculations, their validations and real-time supervision. Safety margins arising from each step of the evaluation chain are described and future directions for temperature evaluation are presented.

 16:15 Peripheral Nerve Stimulation, Implants & Devices: Safe Use & Considerations for MRI Mark Conroy This presentation will describe the MRI related risks to patients with active implantable devices with respect to unintended electrical tissue stimulation. The mechanisms due to RF rectification and gradient induced electrical potential will be described using simplified circuit models. Standard test methods for characterizing device performance in the MRI environment will be described. Finally, risk mitigation strategies and MR Conditional labeling strategies will be reviewed.

 16:45 Adjournment & Meet the Teachers

Weekend Course

### Advanced Clinical MR Imaging in MSK: Part 4

Organizers: Jenny Bencardino, Eric Chang, Garry Gold, Emily McWalter, Edwin Oei, Philip Robinson

 S01 Saturday 15:15 - 16:45 Moderators: Emily McWalter & Alissa Burge

 15:15 Spine Amelie Lutz Back and neck pain are among the most common reasons to seek medical advice. While there are clearly established guidelines for cross-sectional imaging study utilization in the diagnostic work-up, there has been a significant increase in these exams. But cross-sectional imaging findings have been shown to often poorly correlate with patients’ symptoms. In order to better serve patients, we need new tools to enhance or replace existing MRI methods. In this talk, four potential approaches will be discussed to reach this goal: kinematic MRI, novel sequences to complement existing MRI protocols, MRI around metal in the post-operative setting, and PET/MRI.

 15:45 Bone Marrow MRI: from Reconversion to Infiltration Joan C. Vilanova MRI is the technique of choice to analyze the bone marrow.  It is essential to understand the normal composition and distribution of bone marrow and the changes that occur with age, as well as other physiologic factors that can affect those signals. The normal distribution of red and yellow marrow in the skeleton changes with age in a predictable sequence. It is mandatory to understand the standard and advanced techniques such as diffusion and DIXON to perform an accurate evaluation of bone marrow from a physiologic process such as reconversion through an infiltration process.

 16:15 Panel Discussion

 16:45 Adjournment & Meet the Teachers

Weekend Course

### Body MRI: Realities & Controversies: Why Rads?

Organizers: Kathryn Fowler, Kartik Jhaveri, Lorenzo Mannelli, Valeria Panebianco, Scott Reeder, Reiko Woodhams

 S02 Saturday 15:15 - 16:45 Moderators: Kathryn Fowler & Elizabeth Hecht

 15:15 LI-RADS: Pro An Tang The Liver Imaging Reporting And Data System (LI-RADS) was developed to standardize the interpretation, reporting and data collection for imaging examinations in patients at risk for hepatocellular carcinoma (HCC). The system has been developed by committees composed of radiologists, hepatologists, pathologists, and surgeons. In this debate, we will discuss the reasons why LI-RADS is needed and the problems that it solves. In response to current limitations of LI-RADS, we will discuss strategies to address unmet needs and to refine the system in response to new scientific evidence and user feedback.

 15:37 LI-RADS: Con John Leyendecker LI-RADS is an important advance in standardization of HCC imaging and reporting. However, there are still many deficiencies that must be addressed for widespread implementation to succeed. This talk will highlight the concerns of LI-RADS users and the potential ways these concerns can be addressed in the future.

 15:59 PI-RADS: Pro Francois Cornud The PI-RADS  scoring system consists in a visual assessment to detect the presence of suspicious foci within the prostate. It has also been developped to describe signs of tumor extraprostatic extension. Diffusion Weighted Imaging (DWI) plays an unvaluable role to achieve this goal. Very high computed b-values allow to visually increase the conspicuity of tumor foci within the peripheral zone (PZ). DWI has also an important role to increase the sensitivity of T2W-MRI to localise tumor foci originating in the transition zone (TZ), without affecting the specificity. Dynamic Contrast Enhanced MRI plays a role to confirm the presence of a tumor in specific areas, like the  Anterior FibroMuscular Stroma or to detect signs of seminal vesicle invasion, which may remain undetected by DWI alone.

 16:21 PI-RADS - Con Alberto Vargas This talk will emphasize the weaknesses of the Prostate Imaging Reporting and Data system, highlight areas of potential improvement, and discuss ways of dealing with commonly encountered limitations of the guideline in "real-life" scenarios

 16:43 Adjournment & Meet the Teachers

Weekend Course

### MR for Neuropsychiatric Disorders: Part 2

Organizers: Qiyong Gong, John Port

 S03 Saturday 15:15 - 16:45 Moderators: Qiyong Gong

 15:15 MR of Schizophrenia John Sweeney Schizophrenia is a common, debilitating psychiatric disorder with profound impact on cognitive and social functions.  There are several areas in which structural and functional brain imaging are advancing understanding of the pathophysiology of this disorder. Beyond identifying illness associated features, these include: 1) identifying biologically homogeneous subgroups of patients within and across disorders, 2) providing quantitative traits for identifying genetic associations, 3) clarifying how antipsychotic drugs alter brain systems, and 4) characterizing long term progression of illness.  This presentation will review progress in each of these areas.

 15:45 MR of Post-Traumatic Stress Disorder Osamu Abe With the advancement not only in magnetic resonance imaging technologies but also sophisticated post-processing techniques and powerful analytical tools, there should be certain CNS differences between PTSD patients and normal control. Hippocampus, amygdala and prefrontal cortex including anterior cingulate cortex are three key structures in the pathophysiology of PTSD, reproducibly confirmed by structural, diffusional, and functional MRI. Furthermore, these structures are related to the impairment both in salience network and default mode network in patients with PTSD. In this talk, we will show the audience recent results for voxel-based analyses and brain connectivity measured by diffusion and functional MRI.

 16:15 Panel Discussion

 16:45 Adjournment & Meet the Teachers

Weekend Course

### Novel Approaches in Molecular Imaging: Part 2

Organizers: Natalie Serkova, Damian Tyler

 S04 Saturday 15:15 - 16:45 Moderators: Natalie Serkova & Damian Tyler

 15:15 CEST MRI: The Technical Aspects Michael McMahon Chemical Exchange Saturation Transfer (CEST) imaging has emerged as an attractive alternative MRI contrast mechanism to T1 and T2 contrast (1-7). This lecture will cover the basic steps in generating CEST contrast maps, including acquisition, B0 map creation, and Post-processing of CEST MRI data.

 15:37 CEST MRI: The Application Kevin Ray During this presentation, I will discuss some of the difficulties of clinical translation of CEST MRI, highlight the similarities and differences between endogenous and exogenous CEST MRI methods, and outline some of the principle applications of these methods in pre-clinical and clinical settings. Examples of such applications include: (1) pH imaging in ischaemic stroke using endogenous amide proton transfer, (2) pH imaging in cancer using exogenous diaCEST and paraCEST agents, (3) endogenous metabolite concentration imaging (e.g. GluCEST, GagCEST, GlycoCEST), and (4) glucose uptake and perfusion imaging using GlucoCEST.

 15:59 Nanoparticle-Based Imaging: The Technical Aspects Kevin Bennett This presentation will outline the physical chemical and physical basis for nanoparticle contrast agent development, modification, and detection for imaging by MRI. Several emerging nanoparticle agents will be discussed in detail.

 16:21 Nanoparticle-Based Imaging: The Application Heike Daldrup-Link This presentation will provide an overview of clinical applications of iron oxide nanoparticles for MR imaging and PET/MR imaging of patients with cancer. This will include safety considerations, applications for whole body cancer staging, applications for monitoring response to cancer immunotherapies and theranostic (combined therapeutic and diagnostic) applications.

 16:45 Adjournment & Meet the Teachers

Event

### Newbie Reception

 Level 7.4 Rooftop Terrace Saturday 19:00 - 21:00 (no CME credit)

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Weekend Course

### Concurrent MRI: Imaging of Real-Time Events: Part 1

Organizers: Guoying Liu, Elena Vinogradov, Yi-Fen Yen

 N01 Sunday 8:00 - 9:28 Moderators: Chrit Moonen & Bruno Madore

 8:00 Introduction: Concurrent MR Imaging of Real-Time Event Bruno Madore The expression 'concurrent MRI' relates to the use of an MR scanner as part of a larger integrated system, as opposed to a standalone diagnostic tool. Examples include image-guided therapies and hybrid imaging, where changes to tissues can be induced and tracked in real time. In this session, the ability of MRI to capture changes caused by ultrasound energy deposition, radiation therapy, brain plasticity and catheter steering will be presented. In the present talk, our work on hybrid ultrasound+MR imaging and on MR-compatible sensor development will also be detailed.

 8:30 MR Imaging of Neuromodulation Feedback Heidi Johansen-Berg The talk will provide examples of use of MRI in humans to monitor effects of neuromodulation (using feedback or brain stimulation). This can be used to provide insights into healthy brain function and also to develop novel interventions for use in neurological or neuropsychiatric disorders.

 9:00 MR Imaging of Therapeutic Ultrasound Chrit Moonen High Intensity Focused Ultrasound (HIFU), similar to External Beam Radiotherapy (EBRT), can be guided by imaging to plan, provide real-time guidance, and evaluate the therapeutic efficacy. MRI has major advantages for guidance because of its superior anatomic detail, and for HIFU for its thermal mapping. Here, we will pay particular attention how MRI can be used to describe and correct displacement of the target area.

 9:30 Break & Meet the Teachers

Weekend Course

### Image Acquisition & Reconstruction: Part 1

Organizers: Edward DiBella, Neville Gai, Vikas Gulani, Ileana Hancu

 N02 Sunday 8:00 - 9:30 Moderators: Neville Gai & Ileana Hancu

 8:00 MR Basics (Refresher) Recap of Physics of RF & k-Space Acquisition David Higgins Basic MR physics will be reviewed, to provide a foundation for discussion of more advanced concepts in the course. The mechanism of simple radiofrequency excitation will be shown, and the information content of k-space will be illustrated and discussed.

 8:30 Excitation & Parallel Transmission V. Andrew Stenger This lecture will cover the basic concepts needed to understand the theory and implementation of multi-dimensional RF pulses. The ideas of excitation k-space and the Fourier picture for small tip angle RF pulses will be covered in detail. The common k-space trajectories and pulse designs will be discussed. Examples of 2D and 3D spatially selective excitations as well as spectral spatial pulse designs will be presented. Applications including field inhomogeneity compensation and parallel transmission will be covered as well.

 9:00 Cartesian & Non-Cartesian Sampling Schemes - Advantages & Disadvantages Maria Altbach Cartesian sampling is widely used in conventional MRI, however, non-Cartesian sampling schemes (e.g. radial or spiral sampling) offer advantages over Cartesian schemes. Among them is flexibility and efficiency of k-space sampling, motion insensitivity, and the ability to generate images with high spatio-temporal resolution from limited data. The lecture will cover the basic acquisition schemes of Cartesian and non-Cartesian sampling along with the conventional and state-of-the-art reconstruction methods with an emphasis on advantages and disadvantages.

 9:30 Break & Meet the Teachers

Weekend Course

### Basics of Perfusion Imaging: Part 1

Organizers: Fernando Calamante, Hanzhang Lu, Steven Sourbron

 N03 Sunday 8:00 - 9:28 Moderators: Laura Parkes & Ze Wang

 8:00 Physiology of Perfusion Osamu Togao This presentation covers macro- and micro-anatomy of cerebral vasculature and the basic mechanism and physiology of cerebral perfusion.

 8:22 DSC Acquisition & Reconstruction Ashley Stokes Dynamic susceptibility contrast (DSC) MRI methods provide valuable information regarding cerebral perfusion. In this talk, I will discuss current recommendations for best practices in clinical DSC-MRI acquisition and reconstruction. I will also highlight more recent technological advancements for DSC-MRI, along with the associated advantages and trade-offs of these methods. This talk will provide both a basic foundation for understanding current DSC-MRI protocols and insight into future directions for DSC-MRI acquisition and reconstruction.

 8:44 DSC Post-Processing & Modeling (with Demo) Irene Mikkelsen Pivotal in the understanding of processing of Dynamic Susceptibility Contrast perfusion imaging, is the concept of the Residue Function. This function is the underlying tissue function, which is indepent on how the contrast agent is administered to the tissue. This presentation describes the inverse problem and two ways of solving it.

 9:06 DCE Acquisition & Reconstruction Anders Garpebring This talk will describe the basics of dynamic contrast-enhanced (DCE) MRI with focus on the acquisition of the data. Key prerequisites for accurate quantification of perfusion parameters such as Ktrans are sufficiently high spatial and temporal resolution but also accurate quantification of the contrast agent (CA) concentration. The basics of how this can be achieve will be covered in the talk.

 9:28 Break & Meet the Teachers

Weekend Course

### RF Engineering: Coils: Part 1

Organizers: Gregor Adriany, Christoph Juchem, Mary McDougall, Greig Scott

 N04 Sunday 8:00 - 9:30 Moderators: Natalia Gudino & Michael Twieg

 8:00 Basics of Transmission Lines & Power Transfer Nicola De Zanche This lecture covers the basic concepts of RF power transfer over transmission lines. Tools such as scattering parameters and the Smith chart are also discussed.

 8:30 Volume & Surface Coils Christoph Leussler RF coils (antennas) for MRI are designed to generate a RF magnetic field inside the body. Large body volume coils are optimized for the generation of a homogeneous RF magnetic field. Local surface coils are designed to provide high signal to noise ratio. Different designs and related physical aspects are discussed.

 9:00 Multi-Tuned Coils Dennis Klomp Ever wanted to build your own multi-tuned RF coil to enable metabolic imaging? This 30 minute session will start from scratch and ends with you capable to make the most advanced multi-tuned, transmit and receive coil array (in theory)...

 9:30 Break & Meet the Teachers

Weekend Course

### Cardiovascular MRI: Vascular: Part 1

Organizers: James Carr, Tim Leiner

 S01 Sunday 8:00 - 9:20 Moderators: Alex Barker & Christopher François

 8:00 Contrast Agents: Practical Use & Safety Aspects Giles Roditi

 8:20 Contrast-Enhanced MRA Jeremy Collins

 8:40 Non-Contrast-Enhanced MRA Ioannis Koktzoglou This presentation will review established and emerging methods for non-contrast-enhanced magnetic resonance angiography.

 9:00 Basics of Flow Imaging Including Extraction of Quantitative Measurements Jos Westenberg Time-of-Flight and Phase-Contrast imaging will be discussed for their role in aniography. Phase contrast imaging is sensitized to flow velocity, affecting the phase signal of flowing spins. This encoding of velocity enables flow velocity quantitation. Quantitative measures derived from velocity encoding will be discussed: valvular flow mapping with regurgitation assessment, transstenotic pressure drop, kinetic energy distribution and wall shear stress. Furthermore, some potential sources of error of phase contrast imaging will be discussed.

 9:20 Break & Meet the Teachers

Weekend Course

Organizers: Anke Henning, Roland Kreis

 S02 Sunday 8:00 - 9:15 Moderators: Anke Henning & Roland Kreis

 8:00 UHF MRSI: SNR, Speed & Resolution Michal Považan The temporal and spatial resolution of an MR experiment is always influenced by the available signal-to-noise ratio (SNR). In general, SNR increases with a higher static magnetic field (B0). Magnetic resonance spectroscopic imaging may benefit from the ultra-high field, however novel approaches are necessary to overcome the technical challenges that arise at such high magnetic field strengths. In this talk we focus on the specifics of UHF MRSI and present the most recent MRSI methods where the SNR gain can be traded off for higher spatial or temporal resolution.

 8:25 Undersampled Spectroscopic Imaging: Benefits & Pitfalls Ricardo Otazo This lecture presents the main techniques to undersample MR spectroscopic imaging (MRSI) for increased imaging speed, including parallel imaging, compressed sensing and model-based subspace reconstruction

 8:50 Spectral Editing: MEGA & Beyond Ovidiu Andronesi

 9:15 Break & Meet the Teachers

Weekend Course

### Lost in Translation: Neuroradiologists vs Physicists: Part 1

Organizers: Christopher Hess, Alex MacKay

 S03 Sunday 8:00 - 9:50 Moderators: Christopher Hess & Alex MacKay

 8:00 What Am I Looking for in a New Technique? Scott Reeder Acceptance of a new technique generally requires that the acquisition have one or more of the following qualities: faster, more robust/reliable, improved image quality, or offers new information not previously available by other acquisition techniques. Evaluation of new imaging techniques should focus on the specific anatomy of interest or on a specific clinical question, not the overall appearance of an image. Ultimately, determination of clinical impact requires evaluation of diagnostic accuracy, clinical effectiveness and the impact on clinical decision-making. Effective development and translation of new imaging techniques into clinical care requires partnership with clinical imaging experts.

 8:20 Brain Perspective Ari Blitz

 8:40 Spine Perspective Majda Thurnher

 9:00 Head & Neck Perspective Christine Glastonbury While spatial and contrast resolution has greatly advanced in HN MR imaging and extraordinary detail can be seen with cranial nerve and inner ear imaging, our greatest problem in HN imaging remains the routine neck scan. Obtaining at least two-plane imaging of the neck with T1, T2 FS and T1 post contrast FS sequences is necessary. Diffusion weighted imaging has become an essential component of neck and skull base imaging and should also be included in a HN protocol. Trying to achieve at least 6 sequences in a reasonable time frame is problematic for HN MR imaging, and trying to achieve it with patients who have difficulty with secretion management after chemoradiation is even more complex.

 9:20 What Do I Need to Know to Design a New Technique? Jeffrey Duerk

 9:40 Break & Meet the Teachers

Weekend Course

### Introduction to Diffusion: Part 1

Organizers: Stephan Maier, Jennifer McNab, Noam Shemesh

 S04 Sunday 8:00 - 9:30 Moderators: Dmitry Novikov & Jennifer McNab

 8:00 The Physics of Diffusion: What Are We Measuring? Sune Jespersen This lecture covers the basic physics of diffusion. I cover the random walk as a conceptual model of diffusion as well as a tool for simulations. The relation for the mean square displacement is derived, and scenarios leading to time-dependent diffusivities are described, along with their universal short and long time regimes. A central quantity, the propagator, is introduced, and the diffusion equation describing its evolution derived. Examples of solutions are given, and the cumulant expansion as a general framework to describe diffusion in complex media is presented. The connection to the diffusion MR signal is outlined.

 8:22 Diffusion Encoding Using MRI: Single Pulse, Double Pulse, Oscillating Gradients Andrada Ianus

 8:44 Image Encoding for Diffusion MRI: EPI, Spiral, Radial, Multi-Shot, Etc. Robert Frost Single-shot echo-planar imaging, with parallel imaging and simultaneous multi-slice improvements, remains the most commonly used sequence for diffusion imaging of the brain. Many other sequences have been developed with the goal of increasing the spatial resolution of whole-brain diffusion data and their designs are influenced by several considerations including image artefacts, SNR and efficiency, scan time per image, motion sensitivity, and slice acquisition paradigm. These issues will be discussed and illustrated with examples of recent diffusion sequences.

 9:06 Diffusion MR Signal to Quality Data: Preprocessing & Distortion Correction Stamatios Sotiropoulos In this talk, I will present an overview of the issues we encounter in diffusion MRI data and the preprocessing steps needed prior to starting any data analysis. Geometric distortions due to off-resonance effects, distortions due to subject motion, artifacts from physiological noise, detection of outliers and quality control are some of the topics that will be covered. Correcting for artifacts and distortions is key in order to extract the most from the data and allow subsequent analysis in an unbiased and precise manner.

 9:28 Break & Meet the Teachers

Weekend Course

### Concurrent MRI: Imaging of Real-Time Events: Part 2

Organizers: Guoying Liu, Elena Vinogradov, Yi-Fen Yen

 N01 Sunday 10:00 - 11:30 Moderators: Bruno Madore & Chrit Moonen

 10:00 Image-Guided Interventional Stroke Treatment: State of the Art and Future Directions Steven Hetts Periprocedural and intraprocedural imaging for acute ischemic stroke treatment are evolving rapidly. We will discuss the current imaging approach and evolving trends in imaging during stroke treatment.

 10:30 MR Imaging of Drug & Gene Delivery & Therapeutic Effects Kullervo Hynynen

 11:00 MRI-guided Radiation Therapy Cornelis van den Berg This educational discusses the use of MRI in radiation therapy with a focus on MRI-guided radiation therapy. It explains the technological development in relation to how this disruptive technology can change radiation therapy improving outcome and patient toxicity.

 11:30 Panel Discussion

 12:00 Adjournment & Meet the Teachers

Weekend Course

### Image Acquisition & Reconstruction: Part 2

Organizers: Edward DiBella, Neville Gai, Vikas Gulani, Ileana Hancu

 N02 Sunday 10:00 - 11:30 Moderators: Neville Gai & Ileana Hancu

 10:00 Flow & Velocity Imaging Martin Graves The standard method of quantifying cardiovascular velocity and flow in MRI is to use a phase contrast (PC) imaging technique. This presentation will describe the basic principles of the PC method, its practical implementation and clinical optimisation.

 10:30 Motion Compensation: Pulse Sequence & Reconstruction Strategies Pelin Aksit Ciris MRI is slow relative to the time scale of patient motion. Fundamentals of spin physics restrict scan times for most applications to the order of several seconds to minutes. Demand for higher resolution isotropic volumes has further increased acquisition times for some scans. Motion over the course of an MR acquisition has the potential to corrupt imaging data. This talk will describe potential sources of motion and their impact on MR data, then review conventional and emerging strategies for pulse sequence and reconstruction strategies for motion compensation. Advantages and disadvantages of various methods will be discussed.

 11:00 Reduced FOV, Reference Scans, Gradient Pre-Emphasis Xiaohong Joe Zhou This lecture focuses on three pulse sequence strategies to improve the image quality.  First, methods for reducing the field-of-view (FOV) are described using examples of spatial saturation, multiple one-dimensional selective RF pulses, and/or multi-dimensional RF excitation.  Second, reference scans are presented for measuring errors in k-space and enabling various phase corrections in pulse sequences utilizing echo trains.  Third, gradient pre-emphasis is discussed as an effective method to reduce the adverse effects caused by eddy currents. Although these three topics may appear isolated, together they reflect a central theme of how to improve image quality by managing the artifacts.

 11:30 Lunch & Meet the Teachers

Weekend Course

### Basics of Perfusion Imaging: Part 2

Organizers: Fernando Calamante, Hanzhang Lu, Steven Sourbron

 N03 Sunday 10:00 - 11:30 Moderators: Laura Parkes & Ze Wang

 10:00 DCE Post-Processing & Modeling (with Demo) Jesper Kallehauge Post-processing  and modeling of DCE time curves allow for reducing a vast amount of data into a set of parametric maps related to the underlying tissue properties: Permeability, Perfusion, compartmental composition etc. Multiple steps and methods are involved in reaching this point with possible pitfalls resulting in potential misinterpretation of the acquired data. Participants should come away from this seminar understanding these steps and how choices made during data acquisition influence what can sensibly be extracted from the data.

 10:22 ASL Acquisition & Reconstruction Weiying Dai The lecture will cover the key components of arterial spin labeling (ASL) data acquisition and reconstruction, including basic principles, different labeling approaches, background suppression techniques to improve the temporal stability of ASL signals, advanced ASL techniques, readout options, and image reconstruction.

 10:44 ASL Post-Processing & Modeling (with Demo) Michael Chappell The aim of this talk is to introduce the key steps involved in the analysis of ASL data to produce a perfusion-weighted image, a full quantified perfusion image and even images of other haemodynamic parameters. We will see that ASL analysis is for the most part quite simple and eve more advance methods are quite accessible through software tools that are now freely available.

 11:06 ASL: Beyond CBF Peiying Liu This talk will cover advanced ASL-based techniques which provide quantitative measurements of hemodynamic and physiological parameters beyond brain perfusion measured in conventional ASL. Such advances include the implementation of different preparation and acquisitions modules, as well as comprehensive modeling of the signals. With these techniques, new hemodynamic and physiological parameters, including blood oxygenation, tissue transit time, arterial blood volume, vascular compliance, and water permeability of blood-brain barrier, can be obtained.

 11:28 Adjournment & Meet the Teachers

Weekend Course

### RF Engineering: Coils: Part 2

Organizers: Gregor Adriany, Christoph Juchem, Mary McDougall, Greig Scott

 N04 Sunday 10:00 - 11:30 Moderators: Natalia Gudino & Michael Twieg

 10:00 Receive Arrays & Circuity Peter Roemer Fundamental limits of Signal-to-Noise(SNR) ratio exist that cannot be exceeded even with an idealized noiseless receiver coil.  These limits can be approached in certain circumstances with proper coil design.  The objective is to provide the audience with an understanding of these limits and their relationship to practical aspects of coil design. In turn this will help guide the choice of coil element size, array extent, and total coil count for imaging a specific anatomical location.

 10:30 Transmit Arrays & Circuitry for UHF Body Imaging Stephan Orzada As the main magnetic field strength increases, the corresponding RF wavelength is shortened. This leads to pronounced wave effects in the transmit field, causing inhomogeneous excitation. Multi-channel arrays provide additional degrees of freedom to mitigate such effects and to manipulate (or to tailor) RF transmission. Roughly these can be divided in 3 types, namely local arrays, remote circumferential arrays and travelling wave arrays. Examples of these arrays are presented in this educational talk.

 11:00 RF Modelling Joseph Rispoli Radiofrequency (RF) modelling offers an efficient means to characterize the design and performance of RF coils. Simulations are particularly important for establishing MRI scan parameters to ensure safety compliance. This talk provides an overview of several numerical methods that may be employed to model the electrodynamics of RF coils; emphasis is placed on the finite-difference time-domain (FDTD) method and considerations for achieving accurate simulation and validation.

 11:30 Lunch & Meet the Teachers

Weekend Course

### Cardiovascular MRI: Vascular: Part 2

Organizers: James Carr, Tim Leiner

 S01 Sunday 10:00 - 11:40 Moderators: Alex Barker & Christopher François

 10:00 Advanced Techniques: 4D Flow, TKE Pim van Ooij The first part of the talk will show the derivation of clinically relevant parameters (velocity vectors, peak velcocity, wall shear stress) from 4D flow MRI data in laminar flow conditions. the second part of the talk will show the derivation of clinically relevant parameters (turbulent kinetic energy, turbulent wall shear stress) from 4D flow MRI data in turbulent flow conditions.

 10:20 MR Techniques for stroke-related vessel wall imaging Zhaoyang Fan Stroke is one of the major causes of morbidity and mortality worldwide and is the number one cause of adult disability. This disease primarily arises from pathogenesis in a large blood vessel such as the aorta, carotid artery, and intracranial artery and venous sinus. Black-blood MR, commonly known as MR vessel wall imaging (VWI), has emerged as a leading noninvasive imaging modality for directly assessing the vessel wall. Many of previous studies have shown the promise of using MR VWI for characterizing different vessel wall pathologies that potentially result in a stroke. The present lecture will focus on recent (within the last decade) technical developments in MR VWI at the carotid artery, intracranial vessels, and aortic arteries.

 10:40 Cerebrovascular Vessel Wall Imaging from a Clinical Perspective Anja van der Kolk Vessel wall MRI of the supra-aortic and intracranial vasculature has seen an exponential increase in popularity in the last two decades. It can provide a wealth of information on pathologic processes of the vessel wall associated with cerebrovascular diseases – like atherosclerosis, vasculitis, Moyamoya disease and aneurysms – that may be used in the differential diagnosis of vasculopathies, in (stroke) risk assessment, and for planning individual patient-based treatment strategies. This lecture will discuss the clinical potential of vessel wall MRI in these cerebrovascular diseases, with a specific focus on intracranial vessel wall pathology.

 11:00 Chest & Abdominal Iacopo Carbone Cardiovascular MRI: Vascular: Part 2   The target audience of this lecture will be imagers (radiologists or cardiologists), dealing with vascular examinations on regular daily practice. Training doctors will particularly benefit from this lecture.  The presentation will give the basis on how to perform Vascular MRI study of the aorta.The main focus of the presentation will be the acute aortic syndromes, encompassing the whole spectrum of the topic from its pathophysiology and revised classification to different MRI protocols and diagnosis.  At the end of the presentation the audience will be able to recognize and classify the main acute aortic clinical scenarios, differentiating real emergencies from deferrable urgencies and to eventually integrate imaging techniques including CT and echocardiography.

 11:20 Peripheral Vascular Disease Jeremy Collins

 11:40 Adjournment & Meet the Teachers

Weekend Course

Organizers: Anke Henning, Roland Kreis

 S02 Sunday 10:00 - 11:40 Moderators: Anke Henning & Roland Kreis

 10:00 Spectral Simulations in GAMMA: Gradients & Soft Pulses Jan Willem van der Veen Gradients and soft pulses are simulated in GAMMA to correct for technical shortcomings of actual mrs sequences. Simulations are made in a spatial grid to handle chemical shift artifacts, four compartment problem, and the effect of crushers. Described is how to prevent aliasing of the grid with the phase roll of the crushers and how to speed up the calculations. Finally a few practical applications are mentioned to improve quantification of the metabolites.

 10:25 Classification Tools for MRS of Cancer Sabine Van Huffel This lecture explains how to extract diagnostic information from the raw MR spectra possibly combined with information from other MR modalities. Starting from basic and advanced concepts in machine learning, the most important classification methods are surveyed. The application of these classifiers in assessing brain tumor heterogeneity is illustrated in a variety of case studies. In-vivo single-voxel MR Spectroscopy (MRS) as well as chemical Shift Imaging are considered, long-echo time as well as short-echo time acquisition schemes. Moreover, it is shown how to combine these measurements with other basic (T1-weighted,T2-weighted) as well as advanced (PWI, DWI, DTI, DKI) MR modalities.

 10:50 Functional MR Spectroscopy Paul Mullins Proton MRS is often thought of as a static measure. In the past 10 years however, this view has been challenged by several studies showing that it is actually sensitive to fluctuations in neurometabiolites as a result of neural activity. This technique of "functional" MRS (fMRS) is not new, having been around since 1991, however with the ready availability of 3T or higher MRI systems, improved acquisition techniques and accurate fitting packages, fMRS has seen renewed interest. A discussion of the main technique, the result that might be expected and experimental considerations for fMRS will be presented using Glutamate as the model neurometabolite. Attendees should come away with a renewed appreciation for the role 1H-fMRS may play in understanding neural activity and function.

 11:15 Diffusion-weighted MR Spectroscopy Francesca Branzoli Diffusion-weighted 1H MR spectroscopy (DW-MRS) provides unique cell-specific and compartment-specific microstructural information based on the diffusion properties of intracellular metabolites in brain tissue. In this talk, the basic aspects of DW-MRS data acquisition and processing will be presented, together with some clinical and preclinical applications.

 11:15 Adjournment & Meet the Teachers

Weekend Course

### Introduction to Diffusion: Part 2

Organizers: Stephan Maier, Jennifer McNab, Noam Shemesh

 S04 Sunday 10:00 - 11:30 Moderators: Chun-Hung Yeh & Jennifer McNab

 10:00 Diffusion Data Interpretation: Data-Driven Jürgen Finsterbusch The signal of diffusion-weighted MR reflects the tissue structure on a cellular or microstructure scale. Many different approaches have been proposed that aim to characterize diffusion-weighted data or derive diffusion or microstructural tissue properties from it. They could be divided into model- and data-driven approaches. Data-driven approaches either derive diffusion or structural properties directly from the data or, in a broader sense, approximate the data with equations that are “borrowed” from diffusion in simple physical systems or motivated mathematically. The most important of these approaches will be covered in this presentation.

 10:22 Diffusion Data Interpretation: Model-Driven Ariel Rokem Models of diffusion MRI are mathematical expressions that describe the data, summarize it and approximate it. The values of the fit parameters are used to interpret the data in light of the structure of the tissue or its physical properties. This presentation will introduce a framework for model comparison using cross-validation: the model is fit to one part of the data and the model parameters are used to predict the signal in another part of the data. Cross-validation is used to assess parameter reliability, as well as accuracy of the model with respect to the data.

 10:44 Tractography Thijs Dhollander In this introductory course on diffusion MRI based tractography, I will introduce the basics of tractography. I will by no means provide a comprehensive overview or review of all possible techniques and literature, but rather focus on the most essential basics of this area and a selection of its applications. As a result of attending this course, participants should be empowered to participate in the ongoing discussions about the strengths and limitations of tractography, as well as make informed and critical decisions on the use of tractography in their own work.

 11:06 Microstructure for In-Vivo Human Applications Susie Huang This lecture will provide a brief overview of technical considerations involved in in vivo diffusion MR microstructural imaging studies with a focus on human neuroimaging. We will cover biophysical models and signal representations of the diffusion MRI signal as they relate to probing tissue microstructure in the human brain. We will study metrics derived using different diffusion models and acquisition schemes in the setting of normal development and pathological changes in white matter disease. In addition, the specific advantages of high-gradient systems for characterizing tissue microstructure for in vivo human imaging will be explored.

 11:28 Adjournment & Meet the Teachers

Weekend Course

### Lost in Translation: Neuroradiologists vs Physicists: Part 2

Organizers: Christopher Hess, Alex MacKay

 S03 Sunday 10:10 - 12:00 Moderators: Christopher Hess & Alex MacKay

 10:10 Fast Imaging - Parallel Imaging, Compressed Sensing & Beyond John Pauly Throughout the history of MRI a long sequences of techniques have been developed to make images with less data.  When MRI first emerged as a clinical imaging modality, images were acquired by fully sampling a rectangular region in spatial-frequency, or k-space.  Faster acquisitions have been based on the structure of the data, knowledge of the receive array sensitivity, models of the statistics of the image, and, more recently, models of the images themselves.  The common thread is using other knowledge we have about the MRI system and subject to provide additional prior information to reduce the amount of data we need to collect. This talk will highlight this sequence of methods, and look at the potential and challenges they present for clinical application.

 10:32 Modern Functional & Diffusion Imaging Mara Cercignani Diffusion and functional MRI are among the most popular MRI techniques used in neuroscience research. Although basic versions of these techniques have found their way to the clinic relatively soon after their introduction, almost none of the technological advances introduced in the past 20 years have been adopted outside the research setting. This lecture will review some of the latest flavours of diffusion and functional MRI and their potential clinical applications

 10:54 Fingerprinting & Synthetic MRI Nicole Seiberlich

 11:16 MRS of Novel Metabolites Gulin Oz This talk will start with an overview of neurochemicals (beyond NAA, Cr, Cho) measurable by MRS and the cellular/biochemical processes that they reflect, present examples of their utility in addressing novel biological questions, then follow with data quality requirements to be able to reliably quantify these neurochemical profiles and finish with a summary of recent efforts to simplify and automate acquisition of high quality MRS data at 3T and make advanced MRS acquisitions MR technologist friendly.

 11:38 Panel Discussion

 12:00 Adjournment & Meet the Teachers

Weekend Course

### Probing Biomolecules: Magnetic Susceptibility & CEST/MT: Part 1

Organizers: Chunlei Liu, Peter van Zijl, Elena Vinogradov

 N01 Sunday 13:15 - 14:45 Moderators: Jongho Lee & Elena Vinogradov

 13:15 Paramagnetic & Diamagnetic Susceptibility in Tissue Ferdinand Schweser This class will discuss the chemistry and physics of magnetic susceptibility, explaining why some substances affect tissue susceptibility substantially when they are present in very low concentrations whereas other substances need to be present in high concentrations to alter the tissue’s susceptibility measurably. We will discuss the how and why of the differential effects of magnetic susceptibility on gradient-echo magnitude and phase image contrast. An overview of the clinical potential of Quantitative Susceptibility Mapping (QSM) will be provided by discussing the different tissue properties that have been related to magnetic susceptibility in the more recent past.

 13:37 Magnetization Transfer: MTC, NOE, CEST Alexej Jerschow The aim of this presentation is to give the MRI practitioner a good overview of the methods used in CEST and MT imaging, the underlying mechanisms, the current state of the art, and to outline the opportunities and limitations of the methods.

 13:59 Tissue Magnetic Susceptibility Mapping (QSM) Barbara Dymerska

 14:21 What Are We Really Measuring in CEST? Daniel Gochberg This talk will examine the underlying drivers of the CEST signal, and it will discuss the implications for choosing CEST pulse sequences and metrics that maximize solute specificity.

 14:43 Break & Meet the Teachers

Weekend Course

### Image Acquisition & Reconstruction: Part 3

Organizers: Edward DiBella, Neville Gai, Vikas Gulani, Ileana Hancu

 N02 Sunday 13:15 - 14:35 Moderators: Jeffrey Fessler & Berkin Bilgic

 13:15 Parallel Imaging Suchandrima Banerjee With the increasing use of multicoil array for MR signal reception, and motivated by the need to increase acquisition speed, parallel imaging has become as essential part of MR scans. This talk will aim to impart basic understanding and develop an intuition for underlying concepts of parallel imaging reconstruction with a focus on most widely used methods such as SENSE and GRAPPA. Dynamic acceleration and extension to non-cartesian trajectories will be touched upon and the impact of parallel imaging reconstruction on signal-to-noise will be discussed.

 13:35 Basic Sparsity & Compressed Sensing Michael Lustig T.B.A.

 13:55 Low-Rank Methods Bradley Sutton For dynamic imaging or parameter mapping applications, there is a significant amount of spatiotemporal correlations in the data, with many parts of the image sharing similar temporal signal profiles. This results in a data matrix that is low rank. Several methods have been developed to exploit this low-rank structure to achieve very high imaging speed. This talk will describe these low rank methods and demonstrate the imaging speed that can be achieved.

 14:15 Dictionary & Model-Based Methods Mariya Doneva This lecture explains the principles of model-based reconstruction methods and their linearization using dictionaries for MR parameter mapping.

 14:35 Break & Meet the Teachers

Weekend Course

### Advanced Topics in Perfusion MRI: Part 1

Organizers: Fernando Calamante, Hanzhang Lu, Steven Sourbron

 N03 Sunday 13:15 - 14:55 Moderators: Laura Parkes & Thomas Christen

 13:15 Novel Labeling Techniques of ASL Qin Qin This lecture will describe in depth the most recent developments of ASL labeling techniques. PCASL has been further optimized to minimize sensitivity to off-resonance and pulsatile velocity at the labeling plane. Multi-delay PCASL aims to reduce the effect of prolonged transit time. In addition to the improvements of spatially selective ASL, advanced velocity-selective pulse trains have been proposed, for more robustness to eddy current effects, or higher perfusion signal with Fourier transform based velocity selective inversion. Acceleration-selective ASL has also been demonstrated. The pros and cons of each labeling method will be compared.

 13:40 Technical Advances in Body ASL Charlotte Buchanan There have been a number of recent advances in body ASL. ASL has been applied in the heart, liver, kidney and placenta with studies using ASL in diseases such as diabetes, compensated liver cirrhosis and chronic kidney disease. There are however a number of considerations that are required for use of ASL in the body including which labelling and readout schemes to use and how to deal with respiratory and cardiac motion. Efforts are now needed to harmonise techniques and assess variation in sensitivity, specificity and reproducibility in order to make ASL a clinically useable tool for body applications.

 14:05 Is ASL Useful for Brain Mapping? Wen-Chau Wu Since its introduction in 1990's, ASL has gone through abundant developments that have remarkably improved this contrast-material-free technique in data acquisition, image quality, and quantitative modeling. We now have a variety of methods to choose from and a number of review articles to refer to. However, it still seems an open question when it comes to the usefulness of ASL in brain mapping. In this presentation, the issues that have been keeping us from saying yes to the question will be reviewed. The usefulness and caveats of ASL in brain mapping will be discussed from the viewpoint of clinical application.

 14:30 DCE/DSC Beyond Perfusion & Permeability Ben Dickie A healthy cerebrovasculature is crucial for meeting the brains ever changing demand for oxygen and nutrients. Aging and many neurodegenerative diseases lead to insidious vascular changes to vessel size, geometry, and blood brain barrier (BBB) integrity. New approaches to the acquisition and analysis of DCE- and DSC-MRI data are providing novel insights into these cerebrovascular abnormalities, aiding understanding of disease mechanisms and helping to identify novel treatment targets.

 14:55 Break & Meet the Teachers

Weekend Course

### RF Engineering: Coils: Part 3

Organizers: Gregor Adriany, Christoph Juchem, Mary McDougall, Greig Scott

 N04 Sunday 13:15 - 14:25 Moderators: Natalia Gudino & Michael Twieg

 13:15 Dielectric Materials & Resonators Rita Schmidt This talk will review and explain effects in dielectric materials relevant to MRI. It will cover effects due to the body tissues properties, tailoring of the RF field using high permittivity dielectric materials as well as resonant structure implementations. Applications of dielectrics for MRI in a range of magnetic fields will be shown.

 13:50 UHF Coil & Array Design Tamer Ibrahim The clinical and research potential of MRI for whole-body applications at high (≥ 3 tesla) fields and of head applications at ultrahigh (UHF) (≥7 tesla) fields appears to be limitless.  It is however limited by technical challenges.  The most notable of these difficulties include 1) safety concerns regarding exceeding radiofrequency (RF) power deposition in tissue and 2) large image inhomogeneity/voids due to “undesired” RF field inhomogeneity across the anatomy.  The main aim of this course is to explore UHF coil and array designs that aim at addressing these issues.

 14:25 Break & Meet the Teachers

Weekend Course

### Cardiac MR: From the Basics to New Horizons: Part 1

Organizers: Sebastian Kozerke, Reza Nezafat, Bernd Wintersperger

 S01 Sunday 13:15 - 14:35 Moderators: Aleksandra Radjenovic & Peng Hu

 13:15 Cardiac Function Pierre Croisille

 13:35 Myocardial Perfusion Raymond Kwong

 13:55 Scar Imaging Charlene Liew Scar imaging is the backbone of viability quantification of post myocardial infarction scarring. There are also other important applications of scar imaging in various conditions apart from ischaemic cardiomyopathy. This session explores the fundamentals of scar imaging, from physical principles to anatomy and new paradigms.

 14:15 Clinical Needs & Applications David Sosnovik

 14:35 Break & Meet the Teachers

Weekend Course

### Prostate MRI, MRI in Pregnancy & Genitourinary: Part 1

Organizers: Kathryn Fowler, Catherine Hines, Kartik Jhaveri, Lorenzo Mannelli, Valeria Panebianco, Scott Reeder, Reiko Woodhams

 S02 Sunday 13:15 - 14:45 Moderators: Masoom Haider & David Karow

 13:15 Technical Considerations for Prostate MRI Acquisition Alberto Vargas The aim of this session is to summarize the latest technical developments relevant to optimization of clinical prostate MRI protocols

 13:37 Guidelines & Recommendations Jelle Barentsz In this talk, a literature review will be shown of PI-RADS v2. The role of experience and training will be discussed. To ensure optimal quality, certification and quality criteria will be provided. Finally, the role of an expertise network will be emphasized. It will be concluded, that it has been shown that PI-RADSv2 is an adequate ‘‘language’’ for assessing the risk of the presence of clinically significant PCa. The sensitivity is significantly better than that of PI-RADSv1. Nonetheless, there is large heterogeneity that could be reduced by an improved PI-RADSv3 and by training and certification of radiologists. Equally important, however, is the training of urologists and other involved physicians in being able to communicate in the same ‘‘language’’.

 13:59 Prostate MRI & Recurrence Jurgen Fütterer mpMRI is a helpful tool in the evaluation of the treated prostate gland.

 14:21 PET/MRI of Prostate Cancer Joseph Ippolito This educational talk provides an overview of PET/MRI in the evaluation of prostate cancer with a focus on the strengths and weaknesses of PET/MRI versus PET/CT as well as the individual strengths and weaknesses of MRI versus PET. This talk also discusses methods for evaluating initial staging as well as biochemical recurrence in prostate cancer patients and discusses current progress made in the radiopharmaceutical field and its ability to synergize with emerging methods in MRI.

 14:43 Break & Meet the Teachers

Weekend Course

### Is MR/PET Better than MR + PET for the Brain?: Part 1

 13:15 MR/PET Methodology Brain (Advantages & Limitations) Julie Price

 13:45 Attenuation Correction with MR/PET Hongyu An PET/MR is a promising multi-modality imaging approach. Attenuation is by far the largest correction required for quantitative PET imaging. The challenges in MR based PET attenuation correction have negatively impacted the acceptance of PET/MR in clinical trials. Since the inception of PET/MR, MR based attenuation correction approaches have been extensively pursued, especially for brain imaging.  In this presentation, I will provide background of PET/MR attenuation correction and review various methods.  The advantages and disadvantages of these methods are discussed.

 14:15 Hybrid PET/MR in Epilepsy Jie Lu

 14:45 Break & Meet the Teachers

Weekend Course

### Advanced Microstructural Imaging: Part 1

Organizers: Stephan Maier, Jennifer McNab, Noam Shemesh

 S04 Sunday 13:15 - 14:30 Moderators: Jennifer McNab & Noam Shemesh

 13:15 Tissue Architecture & Water Diffusion Obstacles Itamar Ronen

 13:40 Spatial & Temporal Features of Diffusion Encoding Frederik Laun Links between measured signal, the temporal profile of the diffusion-encoding gradients and spatial features of the measured probes will be explained. Among others, the temporal gradient profiles "short-short", "long-long", "long-short", and gradient profiles with multiple gradient pulses will be discussed.

 14:05 Looking from Within: Diffusion of Compartment Specific Metabolites Julien Valette Diffusion-weighted NMR spectroscopy (DW-MRS) offers the unique ability to non-invasively quantify diffusion properties of endogenous brain metabolites in vivo. In contrast to water molecules, which are ubiquitous in biological tissues, most brain metabolites are confined into the intracellular space, and some of them are even thought to exhibit preferential cellular compartmentation (within neurons or glial cells). It is thus expected that DW-MRS may provide specific cellular information. Here we will see how DW-MRS can be related to cellular microstructure, opening perspectives for non-invasive and quantitative measurements of cell-specific morphology under normal and pathological conditions.

 14:30 Break & Meet the Teachers

Weekend Course

### Probing Biomolecules: Magnetic Susceptibility & CEST/MT: Part 2

Organizers: Chunlei Liu, Peter van Zijl, Elena Vinogradov

 N01 Sunday 15:15 - 16:43 Moderators: Jongho Lee & Elena Vinogradov

 15:15 Susceptibility Anisotropy Richard Bowtell

 15:37 CEST MRI of Biomolecules Kannie WY Chan Chemical Exchange Saturation Transfer (CEST) MRI allows us to access molecular information with an enhanced sensitivity. Various contributing proton exchange mechanisms provide ample information for imaging biomolecules and their related pathophysiology. This molecular contrast is sensitive to alterations of exchanging environments in vivo, e.g. CEST contrast of proteins in the brain is different from that in brain tumors with acidic pH. Thus, CEST contrast characterized by the z-spectrum provides readouts for comprehensive physiological and molecular assessments. This talk will present CEST imaging of biomolecules in the brain, and its applications, challenges and opportunities in studying brain tumors and neurological disorders.

 15:59 QSM Clinical Applications Yukunori Korogi The QSM values of the substantia nigra were significantly higher in PD patients than in healthy subjects. QSM showed higher diagnostic performance than R2* mapping for the discrimination between PD patients and controls. The QSM value in GPl increases gradually with age, which allows for the identification of GPm in elderly PD subjects. QSM can detect the abnormalities in normal-appearing basal ganglia in patients with neuropsychiatric systemic lupus erythematosus (NPSLE), which likely represents increased iron deposition.

 16:21 CEST Almost Clinical Applications Seth Smith The goal of this educational presentation is to discuss the important contributions that CEST MRI can have for clinical-translational studies, by highlighting the unique contrasts available and examining the current applications of CEST MRI in the literature.  We will further discuss the potential limitations for more clinically viable adoption of CEST and discuss the opportunities to overcome these limitations, including some studies that have begun to take the clinical leap.  We will close by discussing the potential impact of a unique contrast to clinical-translational studies of the human condition.

 16:43 Adjournment & Meet the Teachers

Weekend Course

### Image Acquisition & Reconstruction: Part 4

Organizers: Edward DiBella, Neville Gai, Vikas Gulani, Ileana Hancu

 N02 Sunday 15:15 - 16:55 Moderators: Berkin Bilgic & Jeffrey Fessler

 15:15 MR Fingerprinting: Introduction Martijn Cloos Magnetic Resonance Fingerprinting (MRF) is an exciting new framework to rapidly acquire simultaneous quantification of multiple tissue properties, but what is it that distinguishes MRF from other quantitative MR techniques?

 15:35 MR Fingerprinting: Reconstruction Considerations Debra McGivney This lecture will outline various considerations associated with the quantification of tissue properties in the framework of MR fingerprinting

 15:55 Machine Learning: Introduction Martin Uecker Machine learning has been a hot topic lately due to the substantial advances in classification, image segmentation and many other tasks where the best-performing methods are now often based on deep neural networks. Machine learning can be applied even when a mathematical description of the model is not at hand or too complicated. This talk will give a brief introduction to machine learning with a focus on artificial neural networks.

 16:15 Machine Learning: Practical Approaches to Reconstruction Mehmet Akçakaya Machine learning methods have found wide use in MRI reconstruction, with a recent focus on artificial neural networks, in particular convolutional neural networks. In this talk, we will overview both model-based and data-driven machine learning approaches for reconstruction. We will also consider practical aspects of implementing deep artificial neural networks for MRI reconstruction.

 16:35 Alternate Reconstruction Workflows: Practical Experience Craig Meyer This educational talk will discuss image reconstruction software platforms that go beyond the platforms provided by the vendors. These platforms can be used for prototyping new reconstruction methods and for enabling capabilities such as real-time interactive scanning. Open-source image reconstruction software libraries accelerate image reconstruction research and enable reproducible research.

 16:55 Adjournment & Meet the Teachers

Weekend Course

### Advanced Topics in Perfusion MRI: Part 2

Organizers: Fernando Calamante, Hanzhang Lu, Steven Sourbron

 N03 Sunday 15:15 - 16:30 Moderators: Thomas Christen & Laura Parkes

 15:15 Advanced Reconstruction Techniques for DCE/DSC Krishna Nayak This talk will review advanced reconstruction methods for DCE-MRI and DSC-MRI.  These methods allow for superior extraction of perfusion, permeability, and other tracer-kinetic parameters of interest (from noisy data), and allow for improvements in spatio-temporal resolution and coverage through the use of sparse data sampling (in k,t space).  We will start by reviewing the current workflow in DCE/DSC, and identifying the opportunity for improvement.  Then we will go through four classes of reconstruction, which have some overlap:  1) spatial and temporal sparsity constraints, 2) data-driven constraints, 3) tracer-kinetic model-based constraints, 4) arterial input function estimation.  Finally, we will discuss the magnitude of the improvement that can be achieved using these techniques.

 15:40 Methods to Validate Quantitative Perfusion Measures Audrey Fan Cerebral blood flow (CBF) is a critical physiological biomarker that select appropriate treatments for cerebrovascular patients and is affected in aging and numerous neurological disorders. However, validation of perfusion biomarkers has been challenging, due to (a) inability to compare with a simultaneous reference standard; and (b) insufficient testing in disease cases, where pathology may interact with the imaging mechanism itself to create CBF inaccuracies. This talk describes how to define an appropriate perfusion measure to address a research/clinical question, and design experiments to validate this measurement.  It also describes multi-modal imaging and challenge studies (cerebrovascular reactivity) contribute confidence in quantitative perfusion measures.

 16:05 New Contrast Agent/Tracer in Perfusion Imaging? Thomas Christen The vast majority of perfusion MR approaches require the injection of a gadolinium based contrast agent or the magnetic labeling of arterial spins. Yet, other types of contrasts or tracers have also been proposed to probe the micro or macro vascular network. This lecture will present recent perfusion techniques based on the use of (1) iron oxide particles, (2) spontaneous or challenge-based BOLD contrast fluctuations, and (3) hyperpolarized compounds. These methods can offer high SNR, short acquisition times, and provide access to new biophysical markers such as microvessel geometry, hematocrit and blood oxygenation.

 16:30 Adjournment & Meet the Teachers

Weekend Course

### RF Engineering: Coils: Part 4

Organizers: Gregor Adriany, Christoph Juchem, Mary McDougall, Greig Scott

 N04 Sunday 15:15 - 16:15 Moderators: Natalia Gudino & Michael Twieg

 15:15 Construction of Rx Arrays Robin Etzel The main aim of this course is to demonstrate MRI researchers/students the basic procedures for phased-array construction and show an optimized protocol for constructing, tuning and decoupling a highly parallel array coil. The goal is to provide a better understanding of the basic experimental RF tools and procedures to facilitate the efficient design and construction of highly parallel MRI receive-arrays. We demonstrate the protocol with the construction of a 16-channel coil array of overlapped surface coil elements.

 15:45 Construction of Rx Arrays Robin Etzel The main aim of this course is to demonstrate MRI researchers/students the basic procedures for phased-array construction and show an optimized protocol for constructing, tuning and decoupling a highly parallel array coil. The goal is to provide a better understanding of the basic experimental RF tools and procedures to facilitate the efficient design and construction of highly parallel MRI receive-arrays. We demonstrate the protocol with the construction of a 16-channel coil array of overlapped surface coil elements.

 16:15 Adjournment & Meet the Teachers

Weekend Course

### Cardiac MR: From the Basics to New Horizons: Part 2

Organizers: Sebastian Kozerke, Reza Nezafat, Bernd Wintersperger

 S01 Sunday 15:15 - 16:55 Moderators: Aleksandra Radjenovic & Elie Mousseaux

 15:15 Myocardial Strain Assessment: Techniques & Processing El-Sayed Ibrahim Different MRI techniques have been developed over the past 30 years for measuring heart mechanics and assessing regional cardiac function. These techniques include tagging with saturation bands, spatial modulation of magnetization (SPAMM), complementary SPAMM (CSPAMM)), harmonic-phase (HARP) analysis, strain-encoding (SENC), displacement-encoding with stimulated-echoes (DENSE), tissue phase-mapping (TPM), cine cardiac feature-tracking (FT), and magnetic resonance elastography (MRE). Further, the recent advancements in in vivo MRI diffusion tensor imaging (DTI) of the heart allowed for better understanding of the cardiac myofiber structure and its effect on the heart function. In this presentation, these techniques will be reviewed along with their clinical applications.

 15:35 Cardiac DTI: Techniques & Postprocessing Andrew Scott Diffusion tensor cardiovascular magnetic resonance is unique in noninvasively assessing cardiac microstructure.  In this session we examine the acquisition and processing techniques used to overcome the difficulties in measuring microscopic diffusion while the heart is moving with the cardiac and respiratory cycles.

 15:55 Clinical Needs & Applications Andrew Taylor Cardiac magnetic resonance (CMR) Imaging is now an essential investigation in the management algorithm of many cardiac conditions. By providing highly accurate structural and functional information, as well as non-invasive tissue characterization, CMR can improve both diagnostic accuracy and quantification of disease severity, leading to more effective healthcare delivery. Evolving CMR techniques, such as those utilizing parametric mapping and 4-dimensional flow quantification, offer new mechanistic insights into disease processes and may ultimately drive the development of novel targets for intervention.

 16:15 T1/T1rho/MT Imaging: Principles & Techniques Walter Witschey

 16:35 T2/T2* Imaging: Principles & Techniques Rohan Dharmakumar This presentation will aim to achieve three tasks: a) outline key cardiac MRI approaches used for T2 and T2* imaging;(b) describe the recent advances in T2 and T2* imaging; and (c) summarize the evolving T2- and T2*-based cardiac MRI-based biomarkers that are being actively studied for improving the clinical management of heart disease.

 16:55 Adjournment & Meet the Teachers

Weekend Course

### Prostate MRI, MRI in Pregnancy & Genitourinary: Part 2

Organizers: Kathryn Fowler, Catherine Hines, Kartik Jhaveri, Lorenzo Mannelli, Valeria Panebianco, Scott Reeder, Reiko Woodhams

 S02 Sunday 15:15 - 16:45 Moderators: Masoom Haider & David Karow

 15:15 Placenta & Pregnant Patient Nathalie Siauve Understanding placental functions remains largely concealed from non-invasive in vivo investigations, although placental insufficiency is responsible for most failures in pregnancy.  Functional MRI offers new perspectives for placental imaging. The vascularisation can be studied with IVIM and the pseudo perfusion coefficient (D*) and the perfusion fraction (f), and with ASL and the blood flow (fASL). DCE MRI also provides a definite assessment of perfusion but requires an exogenous contrast agent. The oxygenation can be studied with BOLD. The placental structure can be studied with DWI and the apparent diffusion coefficient (ADC), and with IVIM and the diffusion coefficient (Dr).

 15:37 Fetal MRI Manjiri Dighe This presentation will review the technique and common indication of fetal MRI with a review of the newer techniques at the end. Illustrative cases will be presented.

 15:59 Renal & Adrenal Pathologies Nicolas Grenier

 16:21 MRU & Bladder David Childs MR urography has proven to be a robust technique for the assessment of the urothelium in both the pediatric (congenital anomalies) and adult (urothelial carcinoma) populations.  Technical challenges (motion, contraindication to contrast, etc.) remain, although newer MRI techniques are increasingly providing solutions to these issues. The increasing use of diffusion and perfusion-weighted imaging has also provided the benefit of multi-parametric data. While the detection of urothelial carcinoma can be achieved with various endoscopic and urographic imaging tests, the accurate staging of tumors (both T and N stage) remains a challenge.  Advances have been achieved in anatomic MRI, perfusion MRI, and diffusion weighted imaging for the T-staging of bladder carcinoma, although the assessment of nodal status remains a significant challenge.  Newly described PET/MRI methods have shown promising results in improving both the specificity of focal urothelial lesions and accurate determination of nodal status, though research is ongoing.

 16:43 Adjournment & Meet the Teachers

Weekend Course

### Is MR/PET Better Than MR + PET for the Brain?: Part 2

 15:15 Dementia Ian Law The benefits of PET/MRI in dementia is still in development. There is no firm evidence to suggest added value of this hybrid technique for dementia work-our over sequential scanning besides convenience for patient and clinician.

 15:45 Multimodal Simultaneous MR-PET Imaging Irene Neuner Simultaneous measurement of PET-MR-EEG has become feasible now a day with the aim of best utilizing the complementary information provided by each modality. Several studies have already shown the possibility of simultaneous measurement of PET-MR-EEG. However such possibility comes with technical and practical challenges.  To that extent, we aim to give an overview about the technical challenges in integrating EEG in to hybrid PET-MR scanners and with possible solutions.

 16:15 Epilepsy Timothy Shepherd

 16:45 Adjournment & Meet the Teachers

Weekend Course

### Advanced Microstructural Imaging: Part 2

Organizers: Stephan Maier, Jennifer McNab, Noam Shemesh

 S04 Sunday 15:15 - 16:55 Moderators: Jennifer McNab & Noam Shemesh

 15:15 Looking from the Outside: Extracellular Diffusion Dmitry Novikov Diffusion in the extracellular space is considered as a function of an increasing diffusion time, equivalent to the coarse-graining of the cellular arrangement over an increasing diffusion length. The three major limits are covered: Short-time S/V limit; long-time limit of approaching the tortuosity asymptote; and the tortuosity limit. The relevant degrees of freedom of cell packing, distinct in each of the three limits, will be discussed.

 15:40 Macro- vs. Micro-Anisotropy Filip Szczepankiewicz What are the distinguishing marks of anisotropic structures in a microscope, and how are these features reflected in the diffusion weighted signal? The lecture will survey the features of anisotropic diffusion on the micro- and macro-scale and connect them to the MRI experiments that may be used to probe such features.

 16:05 How Small Is Small? Probing Very Small Compartment-Short Diffusion Time Manisha Aggarwal This lecture will cover the concepts and applications of oscillating-gradient diffusion MRI acquisition methods to probe tissue microstructure using short effective diffusion times. We will discuss how oscillating diffusion-encoding gradients can be used to characterize restricted diffusion in neuronal tissues, using selective sampling of the temporal diffusion spectrum D(ω) over discrete narrow frequency bands. We will then explore the applications as well as some current limitations of OGSE diffusion MRI acquisitions for probing tissue microstructure over varying length scales.

 16:30 Panel Discussion

 16:55 Adjournment & Meet the Teachers

Plenary Session

### Mansfield Lecture: How Early Life Events Shape Our Brain: An MRI Perspective

 Plenary Hall (Paris Room) Sunday 17:30 - 18:15

 17:00 Welcome

 18:15 How Early Life Events Shape Our Brain: An MRI Perspective

Event

### Opening Reception

 Exhibition Hall Sunday 18:30 - 20:00 (no CME credit)

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Sunrise Session

### Is ASL Ready to Replace Contrast-Agent Perfusion Methods in the Clinic?

Organizers: Fernando Calamante, Hanzhang Lu, Steven Sourbron

 N03 Monday 7:00 - 7:50 Moderators: Lirong Yan & Irene Mikkelsen

 7:00 Yes, It Is Ready! Marion Smits

 7:25 No, It Is Not! Ona Wu

 7:50 Adjournment & Meet the Teachers

Sunrise Session

### Go Faster in Clinical Imaging: Compressed Sensing

Organizers: Jongho Lee, Utaroh Motosugi, Yi-Fen Yen

 N04 Monday 7:00 - 7:50 Moderators: Utaroh Motosugi & Yi-Fen Yen

 7:00 Basic Physics of Compressed Sensing Jong Chul Ye

 7:25 Clinical Applications of Compressed Sensing Akira Yamamoto

 7:50 Adjournment & Meet the Teachers

Sunrise Session

### From Diagnosis to Assessing Therapy Response: Rectal Cancer

Organizers: Kathryn Fowler, Catherine Hines, Kartik Jhaveri, Lorenzo Mannelli, Valeria Panebianco, Scott Reeder, Reiko Woodhams

 S01 Monday 7:00 - 7:50 Moderators: Kathryn Fowler & Marc Gollub

 7:00 Staging/Pre-Op Stephanie Nougaret

 7:25 Response Regina Beets-Tan

 7:50 Adjournment & Meet the Teachers

Sunrise Session

### Advanced Techniques in Cardiovascular MR: More Motion

Organizers: Tim Leiner, Bernd Wintersperger

 S02 Monday 7:00 - 7:50 Moderators: Dana Peters & Walter Witschey

 7:00 Respiratory motion correction Markus Henningsson

 7:25 Correcting Cardiac Motion Keigo Kawaji

 7:50 Adjournment & Meet the Teachers

Sunrise Session

### Application of Molecular Imaging in Cancer

Organizers: Guanshu Liu, Natalie Serkova, Damian Tyler

 S03 Monday 7:00 - 7:50 Moderators: Gregory Metzger & Xiang Xu

 7:00 Recent Technical Developments of Molecular MRI in Cancer Imaging Willem Mulder

 7:25 Clinical Translation & Applications of Molecular MRI in Cancer Craig Malloy

 7:50 Adjournment & Meet the Teachers

Sunrise Session

### Emerging Methods in MSK MRI: Muscle

Organizers: Eric Chang, Garry Gold, Emily McWalter, Edwin Oei, Philip Robinson

 S04 Monday 7:00 - 7:50 Moderators: Erin Englund & Hermien Kan

 7:00 MRI of Muscle Physiology David Bendahan

 7:25 Clinical Muscle Imaging with Emerging Techniques Kimberly Amrami

 7:50 Adjournment & Meet the Teachers

Sunrise Session

### Your Brain on Drugs: Alcohol

Organizers: Andre Obenaus, Pia Maly Sundgren

 S05 Monday 7:00 - 7:50 Moderators: Andre Obenaus & Natalie Zahr

 7:00 Alcohol: WM & Alcohol Natalie Zahr

 7:25 Alcohol: Effects of Alcohol Using MRS Mark Frye

 7:50 Adjournment & Meet the Teachers

Sunrise Session

### Maker: Electronics

Organizers: Gregor Adriany, Matthias Günther, Michael Hansen, Christoph Juchem, Greig Scott

 S06 Monday 7:00 - 7:50 Moderators: Mary McDougall & Greig Scott

 7:00 Fabricating Electronics Pascal Stang

 7:25 Gradient Controller Tutorial Michael Twieg

 7:50 Adjournment & Meet the Teachers

Traditional Poster: Spectroscopy & Non-Proton MR

 Exhibition Hall 1271-1304 Monday 8:15 - 10:15 (no CME credit)

 Exhibition Hall 1369-1393 Monday 8:15 - 10:15 (no CME credit)

Electronic Poster: Diffusion

 Exhibition Hall Monday 8:15 - 9:15 (no CME credit)

Electronic Poster: Neuro

 Exhibition Hall Monday 8:15 - 9:15 (no CME credit)

Study Groups

### Psychiatric MR Spectroscopy & Imaging Business Meeting

 W07 Monday 8:15 - 9:15 (no CME credit)

Study Groups

 W08 Monday 8:15 - 9:15 (no CME credit)

Member-Initiated Symposium

### QSM: From Principles to Clinical Application

Organizers: Ulrich Katscher, Jose Marques, Stefan Ropele

 S05 Monday 8:15 - 10:15 (no CME credit)

 8:15 Introduction to Magnetic Susceptibility Mapping: From Magnetism to Magnetic Fields & Back to the Start! Richard Bowtell1 1University of Nottingham

 8:35 QSM, the Quantitative & Qualitative Susceptibility Mapping Andreas Deistung1 1Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Jena, Germany

 8:50 QSM Technical Implementation Challenges Pascal Spincemaille1 1Cornell University, United States

 9:00 Roundtable: What Is Missing to Make QSM a Clinical Product? Heiko Meyer

 9:00 Roundtable: What Is Missing to Make QSM a Clinical Product? Kim van de Ven1 1Philips Healthcare

 9:00 Roundtable: What Is Missing to Make QSM a Clinical Product? Samir Sharma

 9:15 Iron Accumulation in Neurodegenerative Diseases & Aging: QSM as a New Tool in Clinical Research Birte Forstmann

 9:35 Clinical Applications of a Myelin & Iron Biomarker: The Contribution of QSM to the Study of Multiple Sclerosis Susan Gauthier

 9:55 Debate: Is QSM Ready for Clinical Use as a Diagnostic Tool? Alex Rovira1 1Hospital Universitari Vall D’Hebron

 9:55 Debate: Is QSM Ready for Clinical Use as a Diagnostic Tool? Won-Jin Moon1 1Konkuk University Medical Center

Member-Initiated Symposium

### Challenges & Successes in Imaging the Developing Brain

Organizers: Franklyn Howe, Petra Huppi, Duan Xu

 W05/06 Monday 8:15 - 10:15 (no CME credit)

 8:15 Imaging Early Brain Development: Challenges & Potential of MRI in Infants Jessica Dubois1 1Cognitive Neuroimaging Unit U992, INSERM, Gif-sur-Yvette, France

 8:45 Imaging Function in Developing Preterm Brain with Simultaneous EEG-fMRI Tomoki Arichi1 1Kings College London

 9:15 Quantitative MRI from Childhood to Young Adulthood, Development & Clinical Application Chris Clark1 1UCL Institute of Child Health, United Kingdom

 9:45 Learning-Based Quantification of Baby Brain Development Dinggang Shen1 1UNC-Chapel Hill

Weekday Course

### ISMRM-SMRT Joint Forum: AI in Radiology: Man vs. Machine

Organizers: John Port, Martin Sherriff

 N01 Monday 8:15 - 10:15 Moderators: James Stuppino & John Port

 8:15 The Bright Future of AI/ML in Radiology Bradley J. Erickson1 1Mayo Clinic, United States Artificial intelligence will result in substantial changes in the way that radiology and medicine are practiced. Portions of diagnosis and therapeutics that have a clear pattern are likely to be replaced, augmented, or improved with computer technologies. This will also happen more broadly in all of the world. We must be prepared for these changes, and with proper involvement, we can use this technology to improve everyone's lives.

 8:45 MR Tech View: Will AI/ML Put My Job at Risk? Vera Kimbrell1 1Brigham and Women's Hospital, United States MR Technology and our mother modality Radiology are on the brink of significant change. Computer programming and hardware exist to automat many functions once done by technologists or physicians.  We are grudging moving forward to embrace these improvements.  Somewhat untrusting and with great trepidation we struggle to balance faster exam times, greater ancillary tasks and new technology. We must carefully but quickly earn these new skills and build new workflows in our departments.  MR Technologists are very resilient and with proper education and support can make this new world a better one for our patients and ourselves.

 9:15 Radiologist View: Will AI/ML Put My Job at Risk? Konstantin Nikolaou1 1University Hospitals Tuebingen, Germany The routine use of Artificial Intelligence (AI) in medicine and in medical imaging will become reality, that´s a fact. This is true not only for radiology, but for all medical professions. The question is, how fast this may happen, for which indications and clinical scenarios, and how this will be implemented in our routine workflows. Indeed, implementation and use of AI in radiology is even beneficial and wanted, given the exponentially rising demand of diagnostic imaging and radiological procedures. But will AI replace our profession? Will we have to stop training radiologists? Radiology is always changing and has always been developing alongside new technologies. Therefore, AI will not replace our profession, but it will change our work and it will make us have to train even more. There are a number of reasons why diagnostic radiology has a bright future, implementing AI and ML.

 9:45 Panel Discussion

 10:15 Adjournment & Meet the Teachers

Weekday Course

### Theranostics & Novel Molecular Probes

Organizers: Guanshu Liu, Arvind Pathak

 S02 Monday 8:15 - 10:15 Moderators: Robia Pautler & Xiaolei Song

 8:15 MRI Capable Theranostic Agents Hui Mao1 1Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, United States New generation magnetic resonance imaging (MRI) contrast agents such as nanoparticles can be developed as theranostic agents which integrate the MRI contrast enhancing capability with therapeutic functions. The objective of this lecture is to give the audience an update of the recent developments in MRI enabled theranostics and stimulate the interests and new ideas to further advance the research and clinical translations of MRI enabled theranostics. The rational design of MRI capable theranostics agents, approaches for making the desired theranostic platforms, and MRI methods developed to enable MRI visualization of delivery processes will be discussed and presented with examples.

 8:55 Treatment Monitoring Using Smart MRI Agents Dmitri Artemov1 1Johns Hopkins Univ. Sch. of Medicine, United States In this presentation we will summarize the current state of molecular MRI using biologically active and/or targeted “smart” imaging agents to detect treatment response in several preclinical models of human diseases including cancer.  Both methodological and biological aspects of the MR imaging strategies will be considered.  We anticipate that by the end of the talk the audience should have improved understanding and appreciation of mechanisms and applications of novel state-of-the-art MRI imaging agents to various disease processes in preclinical models.

 9:35 Potential & Requirements for Clinical Translation John Waterton1 1University of Manchester, United Kingdom This presentation discusses clinical translation of novel agents.  Firstly, the conventional diagnostic drug development pathway is outlined.  Then six unconventional pathways are introduced and illustrated with examples from MR and other diagnostic imaging modalities.

 10:15 Adjournment & Meet the Teachers

 10:55 TBD

Power Pitch

### Pitch: CV PowerBeat: Part 1

 Power Pitch Theater A - Exhibition Hall Monday 8:15 - 9:15 Moderators: sergio uribe & Michael Hope (no CME credit)

 1 8:15 Non-invasive pressure estimations by virtual fields – cardiovascular pressure drops from 4D flow MRI David Marlevi 1,2, Bram Ruijsink3, Maximilian Balmus3, Desmond Dillon-Murphy3, Daniel Fovargue3, Kuberan Pushparajah3,4, Pablo Lamata3, C. Alberto Figueroa3,5, Massimiliano Colarieti-Tosti1,6, Matilda Larsson1, Reza Razavi3,4, and David A. Nordsletten3 1Department of Medical Engineering, KTH Royal Institute of Technology, Stockholm, Sweden, 2Clinical Sciences, Karolinska Institutet, Stockholm, Sweden, 3Division of Imaging Sciences and Biomedical Engineering, King's College London, London, United Kingdom, 4Department of Congenital Heart Disease, Evelina Children’s Hospital, London, United Kingdom, 5Departments of Surgery and Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States, 6Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm, Sweden

 2 8:15 The Effect of Model Compliance and Pulsatile Flow for In-Vitro Simulation of the Aorta Timothy Aaron Ruesink1, Matthew Smith2,3, Katrina Ruedinger4, Christopher J François2,3, and Alejandro Roldán-Alzate1,2,4 1Mechanical Engineering, University of Wisconsin, Madison, WI, United States, 2Radiology, University of Wisconsin, Madison, WI, United States, 3School of Medicine and Public Health, University of Wisconsin, Madison, WI, United States, 4Biomedical Engineering, University of Wisconsin, Madison, WI, United States

 3 8:15 3D Hemodynamics Characterization in Patients with Hypercholesterolemia using 4D Flow data and a Finite Element Method. Julio Sotelo1,2, Animesh Tandon3, Andrew Tran3, Joaquín Mura1, Daniel E Hurtado4,5, Tarique Hussain3, and Sergio Uribe1,4,6 1Biomedical Imaging Center, Pontificia Universidad Católica de Chile, Santiago, Chile, 2Department of Electrical Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile, 3Department of Radiology and Biomedical Engineering, University of Texas Southwestern, Dallas, TX, United States, 4Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile, 5Department of Structural and Geotechnical Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile, 6Department of Radiology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile

 4 8:15 Caval Blood Flow Distribution in Fontan Circulation: Comparison between ASL-Measured Pulmonary Perfusion and 4D Flow Joshua S. Greer1,2, Jerry Michael3, Barbara Burkhardt3, Animesh Tandon2,3, Gerald F. Greil2,3,4, Tarique Hussain2,3, and Ananth J. Madhuranthakam2,4 1Bioengineering, University of Texas at Dallas, Richardson, TX, United States, 2Radiology, UT Southwestern Medical Center, Dallas, TX, United States, 3Pediatrics, UT Southwestern Medical Center, Dallas, TX, United States, 4Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX, United States

 5 8:15 Postoperative changes in volume flow rate in the thoracic aorta and the aortic arch branches in patients with aortic valve stenosis: a prospective serial 4D flow MRI study Hiroki Kamada1, Hideki Ota1, Masanori Nakamura2, Yohsuke Imai3, Wenyu Sun1, Yoshiaki Komori4, Ko Sakatsume5, Ichiro Yoshioka5, Yoshikatsu Saiki6, and Kei Takase1 1Department of Diagnostic Radiology, Tohoku University Hospital, Sendai, Japan, 2Department of Electrical and Mechanical Engineering, Nagoya Institute of technology, Nagoya, Japan, 3School of Engineering, Tohoku University, Sendai, Japan, 4Siemens Japan K.K., Tokyo, Japan, 5Division of Cardiovascular Surgery, Tohoku University Hospital, Sendai, Japan, 6Division of Cardiovascular Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan

 6 8:15 4D-Flow-MRI analysis of aortic flow patterns after replacement of the ascending aorta with a physiologically pre-shaped, 90° bent prosthesis Thekla Helene Oechtering1, Jennifer Schlueter1, Malte Maria Sieren1, Michael Scharfschwerdt2, Christian Auer2, Markus Huellebrand3, Hans-Hinrich Sievers2, Joerg Barkhausen1, and Alex Frydrychowicz1 1Department of Radiology and Nuclear Medicine, University Hospital Schleswig-Holstein, Luebeck, Germany, 2Department of Cardiac and Cardiothoracic Vascular Surgery, University Hospital Schleswig-Holstein, Luebeck, Germany, 3Fraunhofer MEVIS, Bremen, Germany

 7 8:15 Impact of field strength (1.5, 3.0 and 7.0 Tesla) and sequence on quantification of aortic flow volumes, peak velocity and wall shear stress using 4D flow MRI Stephanie Funk1,2, Sebastian Schmitter3, Marcel Prothmann1, Carsten Schwenke4, Florian von Knobelsdorff-Brenkenhoff1,5, Andreas Greiser6, Emilie Bollache7, Michael Markl7, and Jeanette Schulz-Menger1,2 1Experimental and Clinical Research Center, a joint cooperation between the Charité Medical Faculty and the Max-Delbrueck Center for Molecular Medicine and HELIOS Hospital Berlin Buch, Department of Cardiology and Nephrology, Berlin, Germany, 2DZHK (German Center for Cardiovascular Research), partner site Berlin, Berlin, Germany, 3Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany, 4SCO:SSIS Statistical Consulting, Berlin, Germany, 5Clinic Agatharied, Department of Cardiology, Ludwig-Maximilians-University Munich, Hausham, Germany, 6Siemens Healthcare, Erlangen, Germany, 7Department of Radiology, Northwestern University, Feinberg School of Medicine, Chicago, IL, United States

 8 8:15 Quantifying the Impact of Velocity Field Distortions on Particle Tracking Techniques Magnus Ziegler1,2, Martin Welander1,3, Marcus Lindenberger1,3, Niclas Bjarnegård1,3, Jonas Lantz1,2, Matts Karlsson1,2, Tino Ebbers1,2, Toste Länne1,3, and Petter Dyverfeldt1,2 1Linköping University, Linköping, Sweden, 2Center for Medical Image Science and Visualization (CMIV), Linköping, Sweden, 3University Hospital Linköping, Linköping, Sweden

 9 8:15 Quantitative MRI detects acute vascular effects of e-cig aerosol inhalation Michael C Langham1, Alessandra Stella Caporale2, and Felix W Wehrli3 13400 Spruce St, University of Pennsylvania, Philadelphia, PA, United States, 2Radiology, University of Pennsylvania, Philadelphia, PA, United States, 3University of Pennsylvania, Philadelphia, PA, United States

 10 8:15 Accelerating 4D-Flow Acquisitions by Reducing TE and TR with Optimized RF and Gradient Waveforms Michael Loecher1, Patrick Magrath2, Eric Aliotta3, and Daniel B Ennis1,2,3 1Radiological Sciences, University of California, Los Angeles, CA, United States, 2Bioengineering, University of California, Los Angeles, CA, United States, 3Biomedical Physics, University of California, Los Angeles, CA, United States

 11 8:15 A Dual Echo, Dual VENC (DEDV) phase contrast method for Simultaneous Measurement of Myocardial and Blood Flow Velocities Afis Ajala1, Jiming Zhang2, Benjamin Cheong2, Pei-Herng Hor1, and Raja Muthupillai2 1Physics and Texas Center for Superconductivity, University of Houston [Main Campus], HOUSTON, TX, United States, 2Baylor St. Luke's Medical Center, Houston, TX, United States

 12 8:15 30 times accelerated 4D flow MRI in the carotids using a Pseudo Spiral Cartesian acquisition and a Total Variation constrained Compressed Sensing reconstruction Eva S Peper1, Lukas M Gottwald1, Qinwei Zhang1, Bram F Coolen2, Pim van Ooij1, Gustav J Strijkers2, and Aart J Nederveen1 1Radiology and Nuclear Medicine, Academic Medical Center (AMC), Amsterdam, Netherlands, 2Biomedical Engineering and Physics, Academic Medical Center (AMC), Amsterdam, Netherlands

 13 8:15 Alterations of Cardiac 4D Hemodynamics and Blood Energetics in Hypertrophic Cardiomyopathy Aakash Gupta1, Michael Markl1,2, Bradley Allen1, Lubna Choudhury3, James Carr1,2,3, Robert Bonow3, and Jeremy Collins1 1Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States, 2Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Chicago, IL, United States, 3Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States

 14 8:15 Dynamic flow imaging and quantification using cine FISS arterial spin labeling Robert R Edelman1,2, Ali Serhal2, Amit Pursnani3, Jianing Pang4, and Ioannis Koktzoglou1,5 1Radiology, NorthShore University HealthSystem, Evanston, IL, United States, 2Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States, 3Medicine, NorthShore University HealthSystem, Evanston, IL, United States, 4Siemens Medical Systems, Chicago, IL, United States, 5Radiology, Prtizker School of Medicine, University of Chicago, Chicago, IL, United States

 15 8:15 4D Flow Cardiac MRI Using Semi-Automated Retrospective Valve Tracking for Assessment of Severe Mitral Insufficiency Carmen PS Blanken1, Jos JM Westenberg2, Pim van Ooij1, Geertruida P Bijvoet3, Steven AJ Chamuleau3, Jean-Paul Aben4, Stefan M Boekholdt1, Aart J Nederveen1, Tim Leiner3, and R Nils Planken1 1Academic Medical Center Amsterdam, Amsterdam, Netherlands, 2Leiden University Medical Center, Leiden, Netherlands, 3Utrecht University Medical Center, Utrecht, Netherlands, 4Pie Medical Imaging, Maastricht, Netherlands

Power Pitch

### Pitch: Trending Topics: Flexible, Material, Portable, Wireless

 Power Pitch Theater B - Exhibition Hall Monday 8:15 - 9:15 Moderators: Fraser Robb & Natalia Gudino (no CME credit)

 16 8:15 The iPRES-W AIR Coil: A Flexible RF Coil for Simultaneous MR Image Acquisition, Wireless Communication, and Localized B0 Shimming Jonathan D. Cuthbertson1,2, Dean Darnell1, Julia Bresticker1,2, Robert Stormont3, Fraser Robb3, Allen W. Song1,2, and Trong-Kha Truong1,2 1Brain Imaging Analysis Center, Duke University, Durham, NC, United States, 2Medical Physics Graduate Program, Duke University, Durham, NC, United States, 3GE Healthcare, Aurora, OH, United States

 17 8:15 Towards wearable MR detection: A stretchable wrist array with on-body digitization Andreas Port1, Jonas Reber1, Christian Vogt2, Josip Marjanovic1, Benjamin Sporrer3, Lianbo Wu3, Andreas Mehmann2, David Otto Brunner1, Thomas Burger3, Gerhard Troester2, Qiuting Huang3, and Klaas Paul Pruessmann1 1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland, 2Electronics Laboratory, ETH Zurich, Zurich, Switzerland, 3Integrated Systems Laboratory, ETH Zurich, Zurich, Switzerland

 18 8:15 High Impedance Detector Arrays for Magnetic Resonance Bei Zhang1,2, Daniel K. Sodickson1,2,3, and Martijn A. Cloos1,2 1Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, NY, United States, 2Center for Advanced Imaging Innovation and Research (CAI2R), New York University School of Medicine, New York, NY, United States, 3The Sackler Institute of Graduate Biomedical Sciences, New York University School of Medicine, New York, NY, United States

 19 8:15 Highly Flexible, Light Weight 24 Channel 3T Bilateral Brachial Plexus Array Worn as a Close Fitting Variable Size Vest Ed Boskamp1, Victor Taracila1, Scott Lindsay2, Robert Stormont2, Reni Biswas3,4, Sheronda Statum3,4, Shane Aldas5, Cesar Barraza5, Fraser Robb1, Christine B Chung3,4, and Won Bae3,4 1G. E. Healthcare Technologies, Aurora, OH, United States, 2G. E. Healthcare Technologies, Waukesha, WI, United States, 3Radiology, University of California, San Diego, La Jolla, CA, United States, 4Radiology, VA San Diego Healthcare System, San Diego, CA, United States, 5Electrical Engineering, University of California, San Diego, La Jolla, CA, United States

 20 8:15 Custom, 3D Sprayed MRI receive coils Alla Zamarayeva1, Michael Liu2, Joseph Corea1, Karthik Gopalan1, Kelvin Pang3, Miki Lustig1, and Ana Claudia Arias1 1EECS, UC Berkeley, Berkeley, CA, United States, 2Georgia Institute of Technology, Atlanta, GA, United States, 3ME, UC Berkeley, Berkeley, CA, United States

 21 8:15 First clinical pilot study using screen-printed flexible MRI receive coils for pediatric applications Simone Angela Winkler1, Joseph Corea2, Balthazar Lechene2, Kendall O'Brien3, John Ross Bonanni3, Fraser Robb4, Greig Scott5, John Pauly5, Michael Lustig2, Ana Claudia Arias2, and Shreyas Vasanawala1 1Department of Radiology, Stanford University, Stanford, CA, United States, 2University of California Berkeley, Berkeley, CA, United States, 3Lucile Packard Children's Hospital Stanford, Stanford, CA, United States, 4GE Healthcare, Aurora, OH, United States, 5Department of Electrical Engineering, Stanford University, Stanford, CA, United States

 22 8:15 Volumetric resonators based on novel materials for 3 T MRI Anna Mikhailovskaya1, Alena Shchelokova1, Dmitry Dobrykh1, Ivan Sushkov2, Alexey Slobozhanyuk1,3, and Andrew Webb4 1Department of Nanophotonics and Metamaterials, ITMO University, Saint Petersburg, Russian Federation, 2Department of Radiology, Vreden Russian Institute of Traumatology and Orthopedics, Saint Petersburg, Russian Federation, 3Nonlinear Physics Center, Research School of Physics and Engineering, Australian National University, Canberra, Australia, 4C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, Netherlands

 23 8:15 New ferroelectric ceramics for transmit efficiency enhancement at 1.5 Tesla Irena Zivkovic1, Alexey Slobozhanyuk2, Elizaveta Nenasheva3, and Andrew Webb1 1Radiology Department, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, Netherlands, 2Department of Nanophotonics and Metamaterials, ITMO University, Saint Petersburg, Russian Federation, 3Giricond Research Institute, Ceramics Co., Saint Petersburg, Russian Federation

 24 8:15 Comparison of a 16-channel monopole/dipole hybrid array with a combined 8-channel monopole + 8-channel high dielectric constant (HDC) disk dipole array for head imaging at 10.5T Myung Kyun Woo1, Lance DelaBarre1, Jerahmie Radder1, Russell Lagore1, Yigitcan Eryaman1, Kamil Ugurbil1, and Gregor Adriany1 1Center for Magnetic Resonance Research, Minneapolis, MN, United States

 25 8:15 Pilot Tone Software Synchronization for Wireless MRI Receivers Greig Scott1, Shreyas Vasanawala2, Fraser Robb3, Pascal Stang4, and John Pauly1 1Electrical Engineering, Stanford University, Stanford, CA, United States, 2Stanford University, Stanford, CA, United States, 3GE Healthcare, Aurora, OH, United States, 4Procyon Engineering, San Jose, CA, United States

 26 8:15 Demonstration of a new volumetric wireless coil for extremities imaging Alena Shchelokova1, Dmitry Dobrykh1, Stanislav Glybovski1, Mikhail Zubkov1, Ekaterina Brui1, Cornelis A.T. van den Berg2, Irina Melchakova1, and Pavel Belov1 1Department of Nanophotonics and Metamaterials, ITMO University, Saint Petersburg, Russian Federation, 2Centre for Image Sciences, University Medical Center Utrecht, Utrecht, Netherlands

 27 8:15 High Precision Wireless Clock Recovery for On-Coil MRI Receivers Using Round-Trip Carrier Phase Tracking. Arne Reykowski1, Paul Redder1, Rodrigo Calderon Rico1, Tracy Wynn1, Tim Ortiz1, Greg Dowling1, Randy Duensing2, and Scott B King1 1Invivo Corporation, Gainesville, FL, United States, 2Philips Research, Hamburg, Germany

 28 8:15 Antenna Design for Wireless Clock Syncing and Q-spoiling in MRI Jonathan Y Lu1, Thomas Grafendorfer2, Shreyas Vasanawala1, Fraser Robb2,3, John M Pauly1, and Greig C Scott1 1Stanford University, Stanford, CA, United States, 2GE Healthcare Inc., Stanford, CA, United States, 3GE Healthcare Inc., Aurora, OH, United States

 29 8:15 3D imaging with a portable MRI scanner using an optimized rotating magnet and 1D gradient coil Patrick McDaniel1, Clarissa Z Cooley2,3, Jason P Stockmann2,3, and Lawrence L Wald2,3 1Massachusetts Institute of Technology, Cambridge, MA, United States, 2Athinoula A Martinos Center for Biomedical Imaging, Charlestown, MA, United States, 3Harvard Medical School, Boston, MA, United States

 30 8:15 Portable single-sided MR: multicomponent T2 relaxometry and depth profiling with a Unilateral Linear Halbach sensor Ashvin Bashyam1,2, Chris J Frangieh1,2, Matthew Li2, Jason Stockmann3,4, and Michael J Cima2,5 1Electrical Engineering & Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States, 2David H. Koch Institute For Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, United States, 3A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 4Harvard Medical School, Boston, MA, United States, 5Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States

Combined Educational & Scientific Session

### Rapid Comprehensive MRI

Organizers: Michael Lustig, Demian Wassermann

 S01 Monday 8:15 - 10:15 Moderators: Oliver Bieri & Christiane Kuhl

 8:15 Clinical Needs Vikas Gulani1 1Case Western Reserve University, United States

 8:45 Technical Trends Julia Velikina1 1University of Wisconsin-Madison, United States

 31 9:15 Non-ECG, free-breathing myocardial T1-T2 mapping of acute myocardial infarction using low-rank tensor MR multitasking Anthony G Christodoulou1, Jaime L Shaw1,2, Christopher Nguyen1, Yibin Xie1, Nan Wang1,2, Qi Yang1,3, and Debiao Li1,2 1Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States, 2Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA, United States, 3Department of Radiology, Xuanwu Hospital, Beijing, China Myocardial tissue characterization by T1-T2 mapping is promising for diagnosing myocardial infarction, ischemia, and more. This is typically performed using ECG triggering and breath-holding, which is uncomfortable and unreliable in patients. This work describes a novel method for non-ECG free-breathing joint T1-T2 mapping using cardiovascular MR multitasking, modeling the underlying 6D multidimensional image—which has 2 spatial dimensions + 4 time dimensions (cardiac, respiratory, T1, and T2)—as a low-rank tensor. T1 and T2 measurements in acute myocardial infarction patients agreed with reference methods and predicted late gadolinium enhancement with 100% sensitivity and 92% specificity.

 32 9:27 5D Flow MRI – Respiratory Motion Resolved Accelerated 4D Flow Imaging Using Low-Rank + Sparse Reconstruction Jonas Walheim1 and Sebastian Kozerke1 1ETH Zurich, Zurich, Switzerland We present a low-rank + sparse reconstruction method which resolves respiratory motion in 4D flow magnetic resonance imaging as a low-rank signal component. Respiratory motion resolved 4D flow MRI data is reconstructed and compared to the total variation based XD-GRASP method and a standard parallel imaging acquisition protocol. Good agreement of the reconstructed results with the reference shows that a low-rank model is effective in resolving respiratory motion in 4D flow magnetic resonance imaging.

 33 9:39 Multi-echo Magnetic Resonance Fingerprinting: Simultaneous derivation of T1, T2, B0, T2*, T2', Tx/Rx phase maps, and T2*-corrected magnitude maps in in-vivo and phantom studies Thomas Amthor1, Jakob Meineke1, Karsten Sommer1, Peter Koken1, and Mariya Doneva1 1Tomographic Imaging, Philips Research Europe, Hamburg, Germany This work describes a Magnetic Resonance Fingerprinting (MRF) implementation using multiple echo acquisitions within one TR. In this way, B0, T2*, R2', and Tx/Rx phase maps are derived in addition to the standard M0, T1, and T2 maps, as demonstrated in in-vivo and phantom experiments. Accounting for the difference in T2 and T2*, the inherent bias of MRF-derived M0 maps can be corrected. The derived R2' map may have diagnostic relevance for neurodegenerative diseases.

 34 9:51 MP2RAGEME: T1, T2* and QSM mapping in one sequence at 7 Tesla Matthan W.A. Caan1,2, Pierre-Louis Bazin2,3,4, Alessio Fracasso2, José Marques5, Serge Dumoulin2, and Wietske van der Zwaag2 1Radiology, Academic Medical Center, Amsterdam, Netherlands, 2Spinoza Centre for Neuroimaging, Amsterdam, Netherlands, 3Social Brain Laboratory, Netherlands Institute for Neuroscience, Amsterdam, Netherlands, 4Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, 5Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands Quantitative T1, T2* and QSM information can be acquired in a single acquisition, using a multi-echo extension of the MP2RAGE sequence, MP2RAGEME. This simultaneous acquisition results in large time savings, perfectly coregistered data and minimal image quality differences. Following a correction for residual transmit B1-sensitivity quantitative T1 and T2* and QSM-values were in excellent agreement with those obtained from separately acquired MP2RAGE and GRE data. Values were also in correspondence with literature. From the MP2RAGEME data, a multiparametric cortical parcellation was obtained, as well as a combined arterial and venous map.

 35 10:03 Simultaneous Proton Density Fat Fraction Imaging and Water T1-Mapping with Low B1+ Sensitivity (PDFF-T1) Richard B Thompson1, Kelvin Chow2, and Justin Grenier1 1Department of Biomedical Engineering, University of Alberta, Edmonton, AB, Canada, 2Cardiovascular MR R&D, Siemens Medical Solutions USA, Inc., Chicago, IL, United States Quantitative multi-parametric MR imaging is an important component of diagnosis and objective staging of diffuse liver disease, reducing the need for biopsy.  The goal of the current study was to validate a new simultaneous proton density fat fraction and water T1-mapping approach (PDFF-T1) with low B1+ sensitivity in a short, patient-friendly breath-hold acquisition. It is shown (simulations, phantoms, in-vivo) that a time-varying flip angle excitation scheme leads to improved accuracy of PDFF and that fat-water separation enables water-specific T1 mapping, all in a single patient-friendly breath-hold, with low sensitivity to inhomogeneity in the transmitted radiofrequency (B1+) field.

 10:15 Adjournment & Meet the Teachers

Oral

### Diffusion MRI: From Fiber Orientation to Connectivity

 N02 Monday 8:15 - 10:15 Moderators: Stamatios Sotiropoulos & Robert Smith

 36 8:15 Super-resolution for spherical deconvolution of multi-shell diffusion MRI data Ben Jeurissen1, Gabriel Ramos-Llordén1, Floris Vanhevel2, Paul M Parizel2, and Jan Sijbers1 1imec-Vision Lab, Dept. of Physics, University of Antwerp, Antwerp, Belgium, 2Dept. of Radiology, Antwerp University Hospital and University of Antwerp, Antwerp, Belgium Multi-tissue constrained spherical deconvolution (MT-CSD) can simultaneously estimate the full white matter fiber orientation distribution function (fODF) and the apparent densities of cerebrospinal fluid and grey matter from multi-shell diffusion MRI data, making it an attractive option for clinical and neuroscientific studies. Unfortunately, MT-CSD at high spatial resolution is challenging due to scan time and signal-to-noise ratio constraints. We propose a new MT-CSD approach that enables super-resolution estimation from multiple thick-sliced data sets with varying slice orientation. Using data acquired on a clinical scanner, we demonstrate high-quality tissue density maps and fODFs at  1×1×1mm3 spatial resolution in under 10 minutes.

 37 8:27 Differential Sensitivity of Various Microstructural Metrics to Training-Induced White Matter Dynamics Debbie Anaby1, Benjamin Tendler2, Chantal M.W. Tax1, Greg D Parker1, Yaniv Assaf3,4, and Derek K Jones1 1Cardiff University Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom, 2Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom, 3Department of Neurobiology, Tel Aviv University, Tel Aviv, Israel, 4Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel Previous in-vivo MRI studies on training-induced WM microstructural dynamics were mostly based on DTI measurements showing changes in FA. The non-specificity of FA as a WM marker stimulated us to obtain a more specific characterization of WM microstructural changes. Using multi-parametric MR with the ‘Tractometry’ approach we show significant changes in the fornix post a navigation working memory task.  Critically, we report here for the first time significant microstructural changes with susceptibility, shown in vast areas of the fornix. Fr, MD, RD and λ1 also show significant changes but in limited areas of the fornix.

 38 8:39 Reducing false positives in tractography with microstructural and anatomical priors Alessandro Daducci1,2,3, Muhamed Barakovic2, Gabriel Girard2, Maxime Descoteaux4,5, and Jean-Philippe Thiran2,3 1Computer Science department, University of Verona, Verona, Italy, 2Signal Processing Laboratory 5 (LTS5), Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland, 3Radiology department, University Hospital Center (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland, 4Sherbrooke Connectivity Imaging Laboratory (SCIL), University of Sherbrooke, Sherbrooke, QC, Canada, 5Department of Nuclear Medicine and Radiobiology, Faculty of Medicine and Health Science, Sherbrooke Molecular Imaging Center, Sherbrooke, QC, Canada Tractography has proven particularly effective for studying noninvasively the neuronal architecture of the brain but recent studies have showed that the high incidence of false positives can significantly bias any connectivity analysis. We present a novel processing framework that can dramatically reduce these false positives, i.e. improving specificity, without affecting the sensitivity, by considering two very basic observations about white-matter anatomy. Our results may have profound implications for the use of tractography to study brain connectivity.

 39 8:51 Fast and accurate white matter bundle segmentation Jakob Wasserthal1,2, Peter F. Neher1, and Klaus H. Maier-Hein1 1Division of Medical Image Computing, German Cancer Research Center (DKFZ), Heidelberg, Germany, 2Medical Faculty, University of Heidelberg, Heidelberg, Germany Automatic white matter fiber bundle segmentation in diffusion-weighted MRI brain scans enables detailed studies of white matter characteristics in healthy and diseased brains. Existing approaches combine processing steps such as tractography, atlas registration and cortical parcellation, resulting in pipelines that are computationally intensive and tedious to set up. We present a novel convolutional neural network-based approach that incorporates or circumvents most of the usually required processing steps  (no registration, no tracking, no parcellation). We demonstrate in 105 subjects from the Human Connectome Project that the proposed approach is much faster than existing methods while providing more accurate results.

 40 9:03 A data-driven groupwise fiber clustering atlas for consistent white matter parcellation and anatomical tract identification of subjects across the lifespan Fan Zhang1, Ye Wu1, Isaiah Norton1, Yogesh Rathi1, Nikos Makris1, and Lauren J. O'Donnell1 1Harvard Medical School, Boston, MA, United States We propose an anatomically curated white matter parcellation atlas generated from a large population of 100 healthy adult subjects, leveraging a well-established data-driven groupwise fiber clustering pipeline and expert neuroanatomy knowledge. We demonstrate the ability of the proposed method to parcellate a total of 541 subjects ranging in age from 1 day to 82 years. The results suggest that our parcellation algorithm  provides high generalization and consistency of white matter parcellation and tract identification for subjects across the lifespan.

 41 9:15 Bundle-Wise Deep Tracker: Learning to track bundle-specific streamline paths Philippe Poulin1, Francois Rheault1, Etienne St-Onge1, Pierre-Marc Jodoin1, and Maxime Descoteaux1 1University of Sherbrooke, Sherbrooke, QC, Canada We propose a novel bundle-wise tracking algorithm based on deep learning and recurrent neural networks. This allows bundle-specific features to be learned directly from the diffusion signal without the need to reconstruct a fiber orientation distribution. With a high amount of examples, the proposed method improves classic algorithms for several quantitative measures such as tracking efficiency, number of valid streamlines, and volume coverage.

 42 9:27 Anchor tracts: a novel concept for reducing false positives in fiber tractography Peter F. Neher1 and Klaus H. Maier-Hein1 1Division of Medical Image Computing, German Cancer Research Center (DKFZ), Heidelberg, Germany Numerous reports have shown that fiber tractography suffers from a difficult sensitivity-specificity tradeoff. We present an approach that leverages knowledge about certain well studied tracts (anchor tracts) in a tractogram to quantitatively assess and score the remaining tracts (candidate tracts) according to their plausibility in conjunction with this context information. We show that our approach has the potential for greatly reducing the number of false positive tracts in fiber tractography while maintaining high sensitivities.

 43 9:39 Investigating U-Shape Fibers from Data-Driven Clustering of White Matter Tractography Jason Kai1, Loxlan W Kasa2, Terry M Peters1,2,3, and Ali R Khan1,2,3 1Medical Biophysics, Western University, London, ON, Canada, 2Biomedical Engineering, Western University, London, ON, Canada, 3Robarts Research Institute, Western University, London, ON, Canada Studies of white matter tractography typically investigate fibers that make up long association tracts, such as the arcuate fasciculus. As a result, the local structural connections comprising short association (cortico-cortical), U-shaped fibers, or U-fibers, are poorly understood. Previous work suggests these fibers play an important role in communication between adjacent cortical regions. We introduce a flexible, data-driven tool incorporating multimodal MRI techniques to aid differentiation of fiber tracts via clustering techniques, including a filter to identify and extract U-fibers. Using this tool, we present a preliminary investigation of U-fibers between controls (N=20) and patients diagnosed with temporal lobe epilepsy (N=19).

 44 9:51 Tractography-based parcellations show limited sensitivity to internal structure Jonathan D Clayden1, David L Thomas2, and Alexander Kraskov3 1Developmental Imaging and Biophysics Section, UCL GOS Institute of Child Health, University College London, London, United Kingdom, 2Neuroradiological Academic Unit, UCL Institute of Neurology, University College London, London, United Kingdom, 3Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, London, United Kingdom Connectivity-based parcellation of subcortical structures using diffusion tractography is a common paradigm. Typically, these analyses imply voxel-level specificity of connectivity, and spatial coherence is taken as imaging-based evidence for anatomically distinct subnuclei. However, by spatially permuting diffusion parameters and repeating the parcellation, we demonstrate that internal structure in diffusion anisotropy is not necessary for a plausible parcellation to be obtained. This suggests that such parcellations should be interpreted with some caution.

 45 10:03 Ultra-high resolution multi-shell dMRI and tractography of the ex vivo human brain using kT-dSTEAM at 9.4T Francisco J. Fritz1, Shubharthi Sengupta1, Robbert L. Harms1, Benedikt A. Poser1, and Alard Roebroeck1 1Cognitive Neuroscience, Maastricht University, Maastricht, Netherlands Here we explore the high resolution acquisition of multi-shell and undersampled diffusion data with 9.4T kT-dSTEAM and analysis of such data for crossing fiber tractography. This permits effective usage of both high SNR and diffusion-weighting inherent to data with multiple b-values and shows superior definition of white matter tracks at ultra-high resolution for tractography. In addition, 3D undersampled acquisition allows more room in the trade-off between acquisition time, resolution, b-values and directions.

Oral

### fMRI: Physiology & Neurovascular Coupling

 N03 Monday 8:15 - 10:15 Moderators: Kai-Hsiang Chuang & Ian Driver

 46 8:15 Covariation of pulse oximetry amplitude and BOLD fMRI across vigilance states Catie Chang1, Pinar Ozbay1, Jacco de Zwart1, Dante Picchioni1, Miranda Chappel-Farley1, Hendrik Mandelkow1, and Jeff Duyn1 1NIH, Bethesda, MD, United States While pulse oximetry (PO) is often used with fMRI to provide the timing of heart beats, few studies have focused on fluctuations in the amplitude of PO waveform in the context of fMRI signals. Here, we examine correlations between spontaneous fMRI signals and PO amplitude (POA) variations, observing a strong dependence on vigilance state. During alertness, POA-fMRI correlations were weaker but encompassed regions comprising the default-mode network. During drowsiness and NREM sleep, POA co-varied extensively with BOLD signals across the brain.

 47 8:27 Mechanisms underlying negative fMRI response in the striatum Domenic H. Cerri1, Daniel Albaugh 1, Brittany Katz1, SungHo Lee1, Weiting Zhang1, Lindsay Walton2, Martin MacKinnon1, Esteban Oyarzabal1, Heather Decot1, Nathalie Van Den Berge1, Chunxiu Yu3, Colleen Mills-Finnerty4, Warren Grill3, Amit Etkin4, Guohong Cui5, Garret Stuber6, and Yen-Yu Ian Shih1 1Neurology & Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States, 2University of North Carolina at Chapel Hill, Chapel Hill, NC, United States, 3Duke University, Durham, NC, United States, 4Stanford University, Stanford, CA, United States, 5National Institute of Environmental Health Sciences, Durham, NC, United States, 6Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States Optogenetic stimulation of striatal neurons and several afferents evoke robust negative fMRI responses in the striatum, while striatal electrophysiological recordings during the same stimulations show increases in neuronal activity. Pharmacological manipulations during D1MSN-induced negative striatal responses suggest responses are downstream of MSN activity, but not interneurons or local DA release. Fiber-photometry data from D2MSNs shows a similar pattern of neurovascular uncoupling/negative coupling. This negative fMRI response is also apparent in the human brain. Our results indicate that positive BOLD in the striatum is mediated through DA release, and that negative BOLD in the striatum is induced by local neuronal activations.

 48 8:39 Visually evoked negative BOLD signal coupled with silenced neuronal activity; an fMRI and intra-cranial electrocorticography study in humans Alessio Fracasso1, Anna Gaglianese2, Serge O Dumoulin1, Nick F Ramsey2, and Natalia Petridou2 1Spinoza Centre for Neuroimaging, Amsterdam, Netherlands, 2University Medical Centre Utrecht, Utrecht, Netherlands Neuroimaging techniques provide a unique window on the study of human brain function in healthy as well as pathological conditions. Intra-cranial electrocorticography (ECoG) at high frequency broadband power is associated with positive blood-oxygenation-level-dependent signal, but the electrophysiological correlates of negative BOLD signals are are less well understood. Here we investigate the relationship between negative BOLD and neuronal population activity measured with ECoG, in humans, using a paradigm that excludes blood stealing as a source of negative BOLD signal.

 49 8:51 Visual contrast levels modulate excitation and inhibition in the human visual cortex – a combined fMRI-MR Spectroscopy study at 7 Tesla Betina Ip1,2, Uzay E Emir1,3, Andrew J Parker2, and Holly Bridge1 1Wellcome Centre for Integrative Neuroimaging, FMRIB Division, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom, 2Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom, 3College of Health and Human Sciences, Purdue University, West Lafayette, IN, United States We used 7 Tesla combined fMRI-MRS to show that simultaneously measured hemodynamic and neurochemical responses in the human visual cortex changed as a function of visual contrast. BOLD change increased linearly to rise in visual contrast, glutamate increased and GABA decreased. Quantification of this change using an excitation:inhibition index demonstrated a switch from inhibitory-dominant to excitatory-dominant neurochemical response. Our results are a step towards disambiguating contributions of cortical excitation and inhibition to stimulus evoked hemodynamic response.

 50 9:03 The potential for gas-free measurements of absolute oxygen metabolism during both baseline and activation states in the human brain Eulanca Y. Liu1,2, Jia Guo3, Aaron B. Simon4, Frank Haist5, David J. Dubowitz2,6, and Richard B. Buxton2,6 1Neurosciences Graduate Program, Medical Scientist Training Program, University of California, San Diego, La Jolla, CA, United States, 2Center for Functional MRI, University of California, San Diego, La Jolla, CA, United States, 3Radiology, Stanford University, Stanford, CA, United States, 4Radiation Medicine and Applied Sciences, University of California, San Diego, La Jolla, CA, United States, 5Psychiatry, Center for Human Development, University of California, San Diego, La Jolla, CA, United States, 6Radiology, University of California, San Diego, La Jolla, CA, United States We tested noninvasive methods to measure absolute oxygen metabolism (CMRO2) in both baseline and activation states without the use of special gases: VSEAN to measure baseline O2 extraction fraction (OEF), and FLAIR-GESSE to measure R2’ to estimate the scaling parameter M. Primary findings were: M derived from R2’ had less variation across subjects compared to hypercapnia-derived M; OEF values were in good agreement with previous PET findings; and, variation of baseline CBF/CMRO2 coupling across subjects does not follow activation coupling, suggesting different mechanisms may be involved. These results support the potential of gas-free methods for quantitative physiological measurements.

 51 9:15 The dynamic BOLD-CBF coupling during resting-state in the aging brain: a dual-echo pCASL study Piero Chiacchiaretta1 and Antonio Ferretti1 1Neuroscience, Imaging and Clinical Sciences, Department of Neuroscience, Imaging and Clinical Sciences - Institute for Advanced Biomedical Technologies, Chieti, Italy Simultaneous acquisition of BOLD and CBF data using ASL allows the study of resting-state brain function from a different perspective with respect to functional connectivity. In particular, recent evidence showed that spontaneous BOLD and CBF fluctuations are strongly coupled in the cortex. Here we show that this coupling is markedly reduced in elderlies with normal cognitive scores, with a regional specific effect in the left supramarginal gyrus, an area known to be involved in different memory functions. These findings suggest that the study of dynamic BOLD-CBF coupling can potentially offer early biomarkers of functional changes in the aging brain.

 52 9:27 Dynamic measurement of oxygen extraction fraction using a Multiple‑Offset‑Spin‑Echo Echo‑Planar Imaging (MOSE‑EPI) pulse sequence Yayan Yin1, Yaoyu Zhang1, Yang Fan2, Bing Wu2, and Jia-Hong Gao1 1Center for MRI Research, Peking University, Beijing, China, 2MR Research China, GE Healthcare, Beijing, China The development of neuroimaging methods to detect functional oxygen extraction fraction (OEF) is crucial for understanding mechanisms of physiologic function and the underlying neuronal activities. However, dynamic measurement of the OEF is currently limited by the long acquisition time. In this study, a novel pulse sequence using a multiple-offset-spin-echo (MOSE) with an echo-planar imaging (EPI) acquisition scheme was developed to improve the temporal resolution of dynamic OEF measurements. A motor task experiment was performed for ten subjects. The OEF activation maps generated through the proposed technique and compared to traditional blood oxygenation level-dependent (BOLD) activation maps.

 53 9:39 Influence of end-tidal CO2 on cerebrovascular reactivity mapping: within-subject and across-subject effects Jill Britt De Vis1, Xirui Hou1, Peiying Liu1, Zheyu Wang2, Siyuan Cheng2, Yang Li1, Harshan Ravi3, and Hanzhang Lu1 1Division of MR Research, Johns Hopkins University, Baltimore, MD, United States, 2Johns Hopkins University, Baltimore, MD, United States, 3National Institutes of Health, Bethesda, MD, United States The relationship between end-tidal (Et) CO2, and the output measure, BOLD signal, is highly non-linear, due to both physiological non-linearity between cerebral blood flow (CBF) and CO2 as well as biophysical non-linearity between CBF and BOLD. In this study, we found that, across subjects, baseline EtCO2 and ΔEtCO2 inversely influenced the measured CVR values. Therefore, these factors should be taken into account when comparing CVR between groups or patients. However, these inter-subject differences appear to have an independent physiological underpinning, as manipulations of these factors within the subject did not seem to have an effect on the measured CVR values.

 54 9:51 Hemodynamic response altered by focused ultrasound-mediated disruption of the blood-brain barrier Nick Todd1, Yongzhi Zhang1, Margaret Livingstone2, Lino Becerra3, David Borsook3, and Nathan McDannold1 1Brigham and Women's Hospital, Boston, MA, United States, 2Harvard Medical School, Boston, MA, United States, 3Boston Children's Hospital, Boston, MA, United States Focused ultrasound (FUS) disruption of the blood-brain barrier (BBB) is a promising technology for achieving targeted delivery of pharmacological agents into the brain. While the method has been shown to be safe from the standpoint of not damaging tissue cells, it causes other changes to local physiology that are not fully understood. This study aims to characterize the effects on the hemodynamic response that FUS BBB opening causes. We present BOLD fMRI data showing the effect and preliminary ASL measurements of cerebral blood flow designed to better understand the effect.

 55 10:03 Active, neuronal-activity-dependent trans-membrane water cycling detected by NMR Ruiliang Bai1, Charles S Springer2, Dietmar Plenz3, and Peter J Basser4 1Interdisciplinary Institute of Neuroscience and Technology, Qiushi Academy For Advanced Studies, Zhejiang University, Hangzhou, China, 2Advanced Imaging Research Center, Oregon Health & Science University, Portland, OR, United States, 3Section on Critical Brain Dynamics, LSN, NIMH, National Institutes of Health, Bethesda, MD, United States, 4Section on Quantitative Imaging and Tissue Sciences, DIBGI, NICHD, National Institutes of Health, Bethesda, MD, United States Transmembrane water cycling has long been thought an entirely passive, diffusion-dominated process.  Recent studies suggest that an energetically active water cycling (AWC) mechanism, driven by Na+-K+-ATPase (NKA) pump activity, also occurs in different cell types, including neurons and astrocytes.  Here we hypothesize that monitoring AWC could provide a new, more direct physical indicator of neuronal activity, which involves much ion cycling and enhanced NKA activity.  By investigating neuronal populations in vitro under resting conditions with spontanotanous activity, and perturbed with tetrodotoxin (TTX), we found TTX simultanously reduces neuronal spiking activity and AWC (by >63%)  suggesting AWC directly reflects neuronal activity.

Oral

### Novel Pulse Sequences

 N04 Monday 8:15 - 10:15 Moderators: Gigi Galiana & Christian Guenthner

 56 8:15 High Spatial Resolution BOLD fMRI Using Simultaneous Multislice Excitation with Echo-Shifting Gradient Echo at 7 Tesla Shi Su1, Na Lu2, Xiaojing Long1, Chunxiang Jiang1, Hang Zhang1, Ye Li1, Rong Xue3, Haifeng Wang1, Lijuan Zhang1, Liang Dong1, Xin Liu1, and Guoxi Xie1,2 1Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China, 2Department of Biomedical Engineering, Guangzhou Medical University, Guangzhou, China, 3Beijing MRI Center for Brain Research, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China Signal to noise gain at ultra-high field has pushed blood oxygen level dependent functional MRI towards high spatial resolution with the benefit of improved accuracy in functional mapping. However, the techniques available for high spatial resolution fMRI are mainly based on echo-planar imaging technique, which faces geometric distortion. In this work, we proposed a technique combining simultaneous multislice excitation with echo-shifting, which can be virtually free from distortion artifacts, for high spatial resolution fMRI. Significant activation was identified in visual and motor experiments with in-plane resolution of 1.0×1.0 mm2 and an acceleration factor of 10 at 7 Tesla.

 57 8:27 Simultaneous Multi-VENC and Multi-Slice (SMVMS) Phase Contrast Imaging Using Dual Steady-State Sequence Suhyung Park1, Liyong Chen2, and David A Feinberg1,2 1Helen Wills Neuroscience Institute, University of California, Berkeley, CA, United States, 2Advanced MRI Technologies, Sebastopol, CA, United States Phase contrast (PC) MRI has been successfully applied to quantify flow velocity over the cardiac cycle by adding bipolar gradients with opposite polarity to cine gradient echo (GRE) sequences with prospective cardiac gating. However, PC-MRI suffers from a couple of disadvantages: 1) velocity aliasing which requires multiple acquisition without prior knowledge of the highest potential velocity and 2) excessive lengthy scan with whole brain coverage. In this work, we propose the Simultaneous Multi-VENC and Multi-Slice (SMVMS) technique to eliminate both issues. Instead of sequentially acquiring multiple slices with low and high velocity encoding (VENC) schemes, this interleaves an echo-shift technique in a Dual TR Steady-State (DSS) sequence using SMS excitation, which allows fast acquisition by sharing low- and high-VENC acquisitions with multiple slices in a single measurement.

 58 8:39 Diffusion interleaved and slice-shuffled (DiSS) imaging for joint diffusion-relaxometry studies Jana Hutter1, Daan Christiaens1, Thomas Roberts1, Paddy Slator2, Anthony N Price1, and Joseph V Hajnal1 1Biomedical Engineering, King's College London, London, United Kingdom, 2Centre for Medical Image Computing, University College London, London, United Kingdom Imaging protocols that allow diverse contrast mechanisms to be sampled with different mixes open up exciting opportunities for joint modelling of tissue properties. However joint sampling with conventional sequence structures can be extremely inefficient and so prohibitively time consuming. Here we explore the joint inversion recovery-diffusion sampling challenge and create an efficient capability by breaking the “one-volume – one encoding” paradigm to interleave the diffusion encoding not per volume but for every slice. Flexible sampling during inversion recovery allowing sufficient samples for a joint fit to be acquired in a much shorter time. The approach has been tested in normal volunteer brain examinations.

 59 8:51 High Contrast and Resolution Simultaneous T1 and T2 MPRAGE at 7T Chan Hong Moon1, Hoby Hetherington1, and Jullie W. Pan1 1MRRC, Dept. of Radiology, University of Pittsburgh, Pittsburgh, PA, United States T2W MRI is useful for lesion detection in neurological disorders. At 7T, while SNR can be excellent for high-resolution imaging, T2W imaging is known to be difficult due to problems with B1 amplitude and homogeneity, as well as low T2 contrast between WM vs. GM. To address these, we developed new simultaneous T1W/T2W MP2RAGE sequence. We simulated the new sequence to optimize brain contrast and implemented on 7T combined with B1-shimmed pTx multi-transceiver and high-order B0 shim. The results show homogeneous contrast of WM vs. GM over whole brain with excellent SAR efficiency, giving high resolution detection of hippocampal sub-structures.

 60 9:03 A 2D multi-shot inversion recovery EPI (MS-IR-EPI) sequence for high spatial resolution T1-mapping at 7T Rosa Sanchez Panchuelo1, Robert Turner1,2,3, Olivier Mougin1, and Susan Francis1 1Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, United Kingdom, 2Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, 3University of Amsterdam, Amsterdam, Netherlands The present study uses an efficient 2D, multi-shot, inversion-recovery EPI (MS-IR-EPI) acquisition that combines separately excited k-space segments after each inversion pulse together with steps in slice ordering to generate T1-maps with high SNR per unit time. We show that although the inversion times systematically vary across slices, consistent T1-maps can be generated across the whole brain. Such T1-maps provide high spatial resolution and SNR, with little image distortion and can be collected in a short acquisition time.

 61 9:15 Silent, 3D MR Parameter Mapping using Magnetization Prepared Zero TE Florian Wiesinger1, Martin A Janich1, Emil Ljungberg1,2, Gareth J Barker2, and Ana Beatriz Solana1 1ASL Europe, GE Healthcare, Munich, Germany, 2Neuroimaging, King’s College London, London, United Kingdom Here we describe a novel method for 3D, quantitative, silent MR parameter mapping based on 1) combined T1 and T2 magnetization preparation, 2) Zero TE image encoding and 3) least-squares dictionary matching.

 62 9:27 Multiband zoom TSE imaging: increasing efficiency with multiband tip-back preparation pulses Anthony N Price1, Lucilio Cordero-Grande1, Shaihan J Malik1, and Joseph V Hajnal1 1School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom Inner volume imaging can be appealing as it negates the need to encode a large field of view when the region of interest resides within a larger tissue structure. However, conventional zoom approaches with precisely limited field of view produce strong saturation throughout the image volume, placing a restrictive lower limit on the minimum TR, in order to avoid reduced signal and contrast. Here we present a new multiband tip-back preparation pulse in combination with a zoom multiband TSE sequence, which realises the benefits of reduced field of view encoding without the penalty of saturation in the intermediate slice areas.

 63 9:39 Simultaneous Magnetic Resonance Angiography and Multiparametric Mapping in the Transient-state Pedro A Gomez1,2, Miguel Molina-Romero1,2, Guido Buonincontri3, Bjoern H Menze1, and Marion I Menzel2 1Technical University of Munich, Munich, Germany, 2GE Global Research, Munich, Germany, 3Imago7 Foundation, Pisa, Italy Quantitative Transient-state Imaging (QTI) is a non-random, dictionary-less MR Fingerprinting alternative. Through iterative reconstructions, QTI recovers a series of contrast-weighted images from transient-state acquisitions and subsequently estimates the parameters that best describe the resulting dynamic signal evolutions. Here, we extend the QTI framework by incorporating a simple velocity model that accounts for blood flowing into and out of the imaging slice. The model, however wrong, can be very useful: it predicts signal hyperintensities in the presence of flow, allowing for the simultaneous reconstruction of MR Angiography images, hundreds of dynamic contrast-weighted images, and their corresponding parametric maps.

 64 9:51 Novel Tumor-Selective Dual-Contrast 3D MRI Toward Zero False-Positiveness in Brain Metastases: A Feasibility Study Hoonjae Lee1,2, Seong-gi Kim1, and Jaeseok Park3 1Center for Neuroscience Imaging Research, Institute for Basic Science (IBS), Suwon, Republic of Korea, 2Department of Brain and Cognitive Engineering, Korea University, Seoul, Republic of Korea, 3Department of Biomedical Engineering, Sungkyunkwan University (SKKU), Suwon, Republic of Korea The purpose of this work is to develop a novel, tumor-selective dual-contrast 3D MRI technique that can clearly differentiate small brain metastases from contrast-enhanced vessels while potentially eliminating false-positiveness in the corresponding diagnosis. After injecting contrast agents, the proposed pulse sequence employs a pair of mixed encodings in each TR, yielding highly tumor-selective, blood-suppressed images from the latter to increase the sensitivity of metastases detection while producing blood-enhanced signals from the former to evaluate the false-positiveness of the detected metastases. It is expected that the proposed method enhances detection sensitivity to brain metastases while substantially reducing false-positiveness.

 65 10:03 Clinical Imaging Potential of FRONSAC Nadine Luedicke Dispenza1, Sebastian Littin2, Maxim Zaitsev2, R. Todd Constable3,4, and Gigi Galiana3 1Department of Biomedical Engineering, Yale University, New Haven, CT, United States, 2Department of Diagnostic Radiology, Medical Physics, University Medical Center Freiburg, Freiburg, Germany, 3Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, United States, 4Department of Neurosurgery, Yale University, New Haven, CT, United States Despite potential for more flexible and efficient encoding that better complements receiver geometry, the past decade of work with nonlinear gradients (NLGs) has shown relatively modest improvements on accelerated image quality. In this work we present the first experimental evidence that the previously introduced ROtary Nonlinear Spatial ACquisition (FRONSAC) can notably improve accelerated image quality, both in vitro and in humans. Furthermore, this work introduces and demonstrates a number of robust and flexible attributes of this method, which are crucial to reducing scan times in a clinical setting.

Oral

### Young Investigator Awards

 S03 Monday 8:15 - 10:15 Moderators: Houchun Hu & Elizabeth Hecht

 66 8:15 Arterial-Spin-Labeling (ASL) perfusion MRI predicts cognitive function in elderly individuals: a four-year longitudinal study Jill B De Vis1, Shin-Lei Peng2, Xi Chen3, Yang Li1, Peiying Liu1, Sandeepa Sur1, Karen M Rodrigue3, Denise C Park3, and Hanzhang Lu1 1MR Research, Johns Hopkins University, Baltimore, MD, United States, 2Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan, 3Center for Vital Longevity, School of Behavioral and Brain Sciences, University of Texas, Dallas, TX, United States Identification of biomarkers that can predict cognitive decline is of utmost importance for advance in dementia pharmacotherapy. In this study, cerebral blood flow (CBF) is investigated as a predictor for cognitive decline in a healthy aging population. We found CBF in the frontal lobe to be most predictive for cognitive decline, specifically for episodic memory and in the older population. This suggest that CBF can be used as a biomarker to identify subjects susceptible to cognitive decline, to identify suitable cohorts for clinical trials, and to monitor the effects of pharmacotherapy.

 67 8:35 Measuring human placental blood flow with multi-delay 3D GRASE pseudo-continuous arterial spin labeling at 3 Tesla Xingfeng Shao1, Dapeng Liu2, Thomas Martin2, Teresa Chanlaw3, Sherin U. Devaskar3, Carla Janzen4, Aisling M. Murphy4, Daniel Margolis2, Kyunghyun Sung2, and Danny J.J. Wang1 1Laboratory of FMRI Technology (LOFT), Mark & Mary Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States, 2Department of Radiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States, 3Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States, 4Department of Obstetrics and Gynecology, Division of Maternal Fetal Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States Placenta influences the health of both a woman and her fetus during pregnancy. Maternal blood supply to placenta can be measured non-invasively using arterial spin labeling (ASL). The purpose of this study is to present a multi-delay pseudo-continuous arterial spin labeling (pCASL) combined with a fast 3D inner-volume gradient- and spin-echo (GRASE) imaging technique to simultaneously measure placental blood flow (PBF) and arterial transit time (ATT), and to study PBF and ATT evolution with gestational age during the second trimester. The PBF values were compared with uterine arterial Doppler ultrasound to assess its potential clinical utility.

 68 8:55 Reverse double inversion-recovery: improving motion robustness of cardiac T2-weighted dark-blood turbo spin-echo sequence Chenxi Hu1, Steffen Huber1, Syed R Latif2, Guido Santacana-Laffitte1, Hamid R Mojibian1, Lauren Baldassarre2, and Dana C Peters1 1Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, United States, 2Department of Internal Medicine, Section of Cardiovascular Medicine, Yale School of Medicine, New Haven, CT, United States The cardiac T2-weighted dark-blood turbo spin-echo (TSE) sequence based on double inversion-recovery (DIR) is subject to motion artifacts due to mismatching of slices from the dark-blood preparation and the TSE readout. Here we propose reverse double inversion-recovery (RDIR), which performs the slice-selective inversion of the DIR preparation in the same cardiac phase as the TSE readout to minimize the slice mismatching. RDIR was evaluated in healthy subjects and patients. Results show that RDIR-TSE achieved a significantly improved image quality in the right ventricle and an improved image quality in the left ventricle compared to the standard DIR-TSE.

 69 9:15 Phase-encoded xSPEN: A novel high-resolution volumetric alternative to RARE MRI Zhiyong Zhang1, Michael Lustig2, and Lucio Frydman1 1Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel, 2Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, CA, United States We have recently introduced cross-term SPatiotemporal ENcoding (xSPEN), a technique with exceptional resilience to field heterogeneities. This study explores a multi-scan extension of xSPEN, which simultaneously yields ky/kz data containing low and high frequency components as well as transposed low-resolution z/y images, with unique downsampling characteristics. A reconstruction scheme converting this information into high resolution 3D images with fully multiplexed volumetric coverage is introduced. The Results provide a series of high-resolution multiscan xSPEN imaging examples and analyzes their sensitivity vis-a-vis commonly used 2D RARE and multi-slab 3D RARE MRI techniques.

 70 9:35 Prospective motion correction with NMR markers using only native sequence elements Alexander Aranovitch1, Maximilian Haeberlin1, Simon Gross1, Benjamin E Dietrich1, Bertram J Wilm1, David O Brunner1, Thomas Schmid1, Roger Luechinger1, and Klaas P Pruessmann1 1Institute for Biomedical Engineering, ETH Zurich and University of Zurich, Zurich, Switzerland A new method for tracking active NMR markers is presented. It requires no alterations of the MR sequence and can be used for prospective motion correction (PMC) in brain MRI. The proposed method collects high-frequency information present due to gradient switching from multiple short, temporally separated snippets within one or more TR of the given sequence. A tracking precision on the order of 10µm and 0.01° (RMS) for translational and rotational degrees of freedom is obtained. The method is demonstrated in-vivo with high-resolution 2D T2*-weighted GRE and 3D MPRAGE brain scans.

 71 9:55 Learning a Variational Network for Reconstruction of Accelerated MRI Data Kerstin Hammernik1,2, Erich Kobler1, Teresa Klatzer1, Michael P Recht2, Daniel K Sodickson2, Thomas Pock1,3, and Florian Knoll2 1Institute of Computer Graphics and Vision, Graz University of Technology, Graz, Austria, 2Center for Biomedical Imaging and Center for Advanced Imaging Innovation and Research (CAI2R), Department of Radiology, NYU School of Medicine, New York, NY, United States, 3Safety & Security Department, AIT Austrian Institute of Technology GmbH, Vienna, Austria In this work, we propose variational networks for fast and high-quality reconstruction of accelerated multi-coil MR data. A wide range of experiments and a dedicated user study on clinical patient data show that the proposed variational network reconstructions outperform traditional reconstruction approaches in terms of image quality and residual artifacts. Additionally, variational networks offer high reconstruction speed, which is substantial for the incorporation into clinical workflow.

Oral

### Hepatobiliary: Neoplasm

 S04 Monday 8:15 - 10:15 Moderators: Satoshi Goshima & Ihab Kamel

 72 8:15 View-Sharing Artifact Reduction with Retrospective Compressed Sensing Reconstruction in the Context of Contrast-Enhanced Liver MRI for Hepatocellular Carcinoma (HCC) Screening Jamil Shaikh1, Paul Stoddard1, Evan Levine2, Stephanie Chang1,3, Albert Roh1, Brian Hargreaves2, Shreyas S. Vasanawala1, and Andreas M. Loening 1 1Radiology, Stanford University, Stanford, CA, United States, 2Electrical Engineering and Radiology, Stanford University, Stanford, CA, United States, 3Radiology, Veteran Affairs Palo Alto Health Care System, Palo Alto, CA, United States View-sharing (VS) increases spatiotemporal resolution in dynamic contrast-enhanced (DCE) MRI by temporally sharing high frequency k-space data across contrast phases. However, this temporal sharing results in respiratory motion occurring in any single phase to propagate artifacts across all phases. Compressed sensing (CS) can eliminate need for VS by recovering missing k-space data from pseudorandom under-sampling, reducing temporal blurring while maintaining spatial resolution. We tested CS versus VS in the setting of DCE MRI for HCC. CS reduced respiratory artifacts, produced images with a more synthetic appearance, and did not result in a difference in lesion detection.

 73 8:27 Dynamic Gd-EOB-DTPA enhanced MR imaging of the liver: Value of High Temporal-resolution Images with Parallel imaging and Compressed Sensing Takayuki Masui1, Motoyuki Katayama1, Mitsuteru Tsuchiya1, Masako Sasaki1, Kenshi Kawamura1, Yuki Hayashi1, Takahiro Yamada1, Naoyuki Takei2, Yuji Iwadate2, Kang Wang3, and Dan Rettmann4 1Radiology, Seirei Hamamatsu General Hospital, Hamamatsu, Japan, 2Global MR Applications and Workflow, GE Healthcare, Hino, Japan, 3Global MR Applications and Workflow, GE Healthcare, Madison, WI, United States, 4Global MR Applications and Workflow, GE Healthcare, Rochester, MN, United States With ARC and CS, breath-hold dynamic Gd-EOB-DTPA enhanced MR imaging for the liver can be successfully performed with acceptable image quality and lesion recognitions on a clinical 3T magnet. High temporal resolution images with CS-LAVA for dynamic contrast MR study may give us benefits in comparison of Turbo-LAVA with lower temporal resolutions.

 74 8:39 Prospective Comparison of Gadoxetic Acid-Enhanced Liver MRI And Contrast-Enhanced CT With Histopathological Correlation For Preoperative Detection Of Colorectal Liver Metastases Following Chemotherapy And Potential Impact On Surgical Plan Kartik Jhaveri1, Sandra Fischer1, Hooman Hosseini Nik1, Ravi Menezes1, Steven Gallinger1, and Carol-Ann Moulton1 1UHN, Toronto, ON, Canada Complete resection of colorectal cancer liver metastases increases survival and is a recommended therapeutic option. Thus accurate detection of liver metastases is crucial. Many patients receive preoperative chemotherapy which often causes hepatic steatosis and decreases sensitivity of CT in detecting liver metastases. This prospective study with histopathological correlation compared the diagnostic performance of gadoxetic acid Liver MRI in the preoperative detection of liver metastases following chemotherapy including the influence of hepatic steatosis and lesion size. We also evaluated the potential change in the hepatic resection plan due to inclusion of gadoxetic acid MRI compared to CT.

 75 8:51 Combined Gadoxetic Acid and Gadobenate Dimeglumine Enhanced Liver MRI for Liver Metastasis Detection: A Parameter Optimization Study Gesine Knobloch1, Timothy Colgan1, Xiaoke Wang1,2, Tilman Schubert1, Diego Hernando3, and Scott Reeder1,2,3,4,5 1Department of Radiology, University of Wisconsin – School of Medicine and Public Health, Madison, WI, United States, 2Department of Biomedical Engineering, University of Wisconsin – School of Medicine and Public Health, Madison, WI, United States, 3Department of Medical Physics, University of Wisconsin – School of Medicine and Public Health, Madison, WI, United States, 4Department of Medicine, University of Wisconsin – School of Medicine and Public Health, Madison, WI, United States, 5Department of Emergency Medicine, University of Wisconsin – School of Medicine and Public Health, Madison, WI, United States The detection of small perivascular metastatic lesions can be challenging with gadoxetic acid-enhanced liver MRI because both, blood vessels and metastases appear hypointense during the hepatobiliary phase. We sought to demonstrate the feasibility of combined gadoxetic acid (GA)/gadobenate dimeglumine (GD) liver MRI for improved lesion detection and optimize the imaging protocol regarding GA-dosing, imaging time after GD-injection and flip angle. Preliminary results show a homogenously enhanced liver and vasculature (“plain-white-liver”) 1-3min after GD-bolus detection with optimal contrast using flip angles of 25-35°. The combined GA/GD protocol has potential to improve the diagnostic performance of hepatobiliary phase liver MRI.

 76 9:03 Gadoxetate-enhanced abbreviated MRI is reliable and effective for HCC surveillance in high-risk patients. Ryan L Brunsing1, Dennis Chen1, Alexandra Schlein1, Paul Murphy2, Yesenia Covarrubias1, Alex Kuo3, Michel Mendler4, Irene Vodkin4, Rohit Loomba4, Yuko Kono4, and Claude B Sirlin1 1Liver Imaging Group, University of California San Diego, San Diego, CA, United States, 2Radiology, University of California San Diego, San Diego, CA, United States, 3Gastroenterology and Hepatology, Virginia Mason Medical Center, Seattle, WA, United States, 4Hepatology, University of California San Diego, San Diego, CA, United States Gadoxetate enhanced abbreviated MRI (AMRI) is a simple, rapid acquisition protocol aimed at reducing the cost and increasing the throughput of MRI-based HCC surveillance. Here we analyze 330 consecutive patients with cirrhosis or chronic HBV who underwent at least one screening AMRI. The rate of HCC detected at cross sectional analysis (3.3%) was in line with published incidence of HCC, while the technical failure rate was low (5.8%) despite high prevalence of cirrhosis and ascites. Longitudinal analysis demonstrated high sensitivity, specificity, and negative predictive value in HCC detection, using a composite reference standard.

 77 9:15 Volumetric Apparent Diffusion Coefficient Histogram Analysis in Differentiating Intrahepatic Cholangiocarcinoma from Hepatocellular Carcinoma Xianlun Zou1, Yaqi Shen1, Zhen Li1, and Daoyu Hu1 1Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China Accurate differentiation between intrahepatic cholangiocarcinoma (IHCC) and hepatocellular carcinoma (HCC) is essential for adequate treatment planning. In the present study, non-contrast volumetric ADC histogram analysis was employed to differentiate IHCC (n=33) and HCC (n=98). The results suggested that except the kurtosis and skewness, all the volumetric ADC histogram parameters, were helpful in distinguishing IHCC from HCC. Among all the parameters, 75th percentile ADC was most helpful to distinguish the two diseases. This non-contrast method provides useful information in differentiating IHCC from HCC, it benefits patients who are contraindicate to contrast agents.

 78 9:27 Motion Correction of Diffusion-weighted imaging in the analysis of Apparent Diffusion Coefficient for preoperative staging of hepatocellular carcinoma Wu Zhou1, Qiyao Wang2, Guoxi Xie3, Fei Yan2, Yaoqin Xie2, Guangyi Wang4, Zaiyi Liu4, Changhong Liang4, Hairong Zheng2, and Lijuan Zhang2 1School of Medical Information Engineering, Guangzhou University of Chinese Medicine, Guangzhou, China, 2Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China, 3Guangzhou Medical University, Guangzhou, China, 4Department of Radiology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China Preoperative tumor staging of hepatocellular carcinoma (HCC) is a critical issue that influences tumor recurrence and patient survival in clinical practice. One of the challenges encountered in DWI of the liver is cardiac motion that can affect the accuracy of ADC measurements, which may inevitably influence the performance of DWI for HCC staging. However, the impact of motion for ADC and HCC staging has not been thoroughly investigated. In this work, we quantitatively investigate the relationship of motion correction, ADC and staging of HCC in order to widen the understanding of applications in DWI for tumor assessment.

 79 9:39 Partial velocity-compensated diffusion encoding for combined motion compensation and residual vessel signal suppression in liver DWI Anh T Van1, Barbara Cervantes1, Tetsuo Ogino2, Johannes M Peeters3, Andreas Hock4, Ernst J Rummeny1, Rickmer Baren1, and Dimitrios C Karampinos1 1Department of Diagnostic and Interventional Radiology, Technical University of Munich, Munich, Germany, 2Philips Japan, Tokyo, Japan, 3Philips MR Clinical Science, Best, Netherlands, 4Philips Healthcare, Hamburg, Germany Despite its strong clinical significance in lesion detection and tumor staging, liver DWI remains challenged by its strong sensitivity to motion effects. Motion-compensated diffusion encoding schemes have been recently proposed to improve DW liver signal homogeneity especially in the left liver lobe, a region typically affected by cardiac motion. However, motion-compensated diffusion encoding is associated with hyperintense vessel signal even at high b-values, which can obscure lesion detection. The present work proposes a partial velocity-compensated diffusion encoding for combined motion compensation and residual vessel signal suppression in liver DWI.

 80 9:51 Characterization of Abdominal Neoplasms using a Fast T2 Mapping Radial TSE Technique Mahesh Bharath Keerthivasan1,2, Diego Blew2, Jean-Philippe Galons2, Diego Martin2, Ali Bilgin1,3, and Maria Altbach2 1Electrical and Computer Engineering, University of Arizona, Tucson, AZ, United States, 2Medical Imaging, University of Arizona, Tucson, AZ, United States, 3Biomedical Engineering, University of Arizona, Tucson, AZ, United States Radial turbo spin-echo (RADTSE) based methods have been proposed for quantitative T2 mapping. RADTSE yields high spatio-temporal resolution and allows the reconstruction of co-registered images at multiple TE times from a short acquisition (i.e. a breath hold). We investigate the clinical utility of RADTSE for the quantitative characterization of abdominal neoplasms.

 81 10:03 Using Tumor Stiffness as a Potential Biomarker for Predicting Hepatocellular Carcinoma Recurrence Jin Wang1, Hao Yang1, Yong Liu2, Sichi Kuang1, Bingjun He1, Yao Zhang1, Qungang Shan1, Jingbiao Chen1, TianHui Zhang1, Kevin J. Glaser3, Cairong Zhu4, Jun Chen3, Meng Yin3, Bogdan Dzyubak3, Sudhakar K. Venkatesh3, and Richard L. Ehman3 1Department of Radiology, the Third Affiliated Hospital of Sun Yat-sen University(SYSU), Guangzhou, China, 2Department of Pathology, the Third Affiliated Hospital of Sun Yat-sen University(SYSU), Guangzhou, China, 3Department of Radiology, Mayo Clinic, Rochester, MN, United States, 4Department of Epidemiology and Biostatistics, West China School of Public Health Sichuan University, ChengDu, China Hepatocellular carcinoma (HCC) is a highly aggressive cancer and one of the leading causes of cancer-related deaths around the world. Our preliminary analysis of 78HCCsshowed 3D MRE is a promising, noninvasive technique for predicting the early recurrence of HCCs after hepatic resection. MRE-assessed tumor stiffness correlates with features such as encapsulation, macrovascular invasion, and histological grade. In the future, larger studies will improve our understanding of the relationship between HCC stiffness, invasiveness, and outcome for better allocation of treatment strategies and surveillance follow-up.

Oral

### Multiple Sclerosis: Lesions Everywhere

 S06 Monday 8:15 - 10:15 Moderators: Irene Vavasour & Frederik Barkhof

 82 8:15 Spatial Distribution of Multiple Sclerosis lesions in the Cervical Cord Dominique Eden1, Charley Gros1, Atef Badji1,2, Sara Dupont1,3, Josefina Maranzano4, Ren Zhuoquiong5, Yaou Liu5,6, Jason Talbott3, Elise Bannier7,8, Anne Kerbrat9, Gilles Edan9,10, Pierre Labauge11, Virginie Callot12,13, Jean Pelletier12,13, Bernard Audoin12,14, Henitsoa Rasoanandrianina12,13, Paola Valsasina15, Massimo Filippi15, Rohit Bakshi16, Shahamat Tauhid16, Ferran Prados17, Marios Yiannakas17, Hugh Kearney17, Olga Ciccarelli17, Constantina A Treaba18, Caterina Mainero18, Russell Ouellette18,19, Tobias Granberg18,19, Sridar Narayanan4, and Julien Cohen-Adad1,20 1NeuroPoly Lab, Polytechnique Montreal, Montreal, QC, Canada, 2Faculty of Medicine, University of Montreal, Montreal, QC, Canada, 3Department of Radiology and Biomedical Imaging, Zuckerberg San Francisco General Hospital, University of California, San Francisco, CA, United States, 4Montreal Neurological Institute, Montreal, QC, Canada, 5Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing, China, 6Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China, 7Department of Radiology, University Hospital of Rennes, Rennes, France, 8University of Rennes, INRIA, CNRS, INSERM, Rennes, France, 9University Rennes, INRIA, CNRS, INSERM, Rennes, France, 10Department of Neurology, University Hospital of Rennes, Rennes, France, 11University Hospital of Montpellier, Montpellier, France, 12CRMBM, CNRS, Aix-Marseille University, Marseille, France, 13CEMEREM, Hôpital de la Timone, AP-HM, Marseille, France, 14Department of Neurology, CHU Timone, APHM, Marseille, France, 15Neuroimaging Research Unit, INSPE, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy, 16Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States, 17Queen Square MS Centre, UCL Institute of Neurology, Faculty of Brain Sciences, University College London, London, United Kingdom, 18Massachusetts General Hospital, Boston, MA, United States, 19Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden, 20Functional Neuroimaging Unit, CRIUGM, Université de Montréal, Montreal, QC, Canada The study of the spatial distribution of multiple sclerosis (MS) lesions in the cervical spinal cord provides a means to further understand the disease pathophysiology. In this study we involve 358 patients across 7 sites, where cervical lesions were manually segmented. Using Spinal Cord Toolbox, lesion segmentations were registered to a common-space template and voxel-based lesion probability maps (LPMs) were computed across the patient population to assess lesion topography. Results revealed a predominance of lesions in the upper cord (C1-C3) and dorsal column, which confirms prior histopathology work and encourages further study of associations between cervical spine lesion volume and distribution with clinical status.

 83 8:27 Spatiotemporal development of spinal cord lesions in a primate model of multiple sclerosis Jennifer A. Lefeuvre1,2, Pascal Sati1, Cecil Chern-Chyi Yen3, Seung Kwon A. Ha1, Wen-Yang Chiang3, Mathieu D. Santin2, Steven Jacobson4, Afonso C. Silva3, Stéphane Lehéricy2, and Daniel D. Reich1 1NINDS, National Institutes of Health, bethesda, MD, United States, 2CENIR, Institut du Cerveau et de la Moelle epinière, Paris, France, 3National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States, 4National Institute of Neurological Disorders and Stroke, National Institutes of health, Bethesda, MD, United States The spatiotemporal development of spinal cord (SC) lesions in multiple sclerosis (MS) is poorly understood, despite the high prevalence of these lesions and their important contribution to patient disability. In this study, we report for the first time the serial imaging of SC lesions in a nonhuman primate model of MS. The results demonstrated substantial clinical and imaging features shared between this animal model and human MS. In particular, we observed focal and subpial demyelinating lesions that appeared at disease onset and proceeded to affect much of the entire cord over the course of several weeks to months.

 84 8:39 Thalamic lesions, thalamic volume and cognitive deficit in secondary progressive MS Floriana De Angelis1, Jonathan Stutters1, Arman Eshaghi1, Ferran Prados1,2, Domenico Plantone1, Anisha Doshi1, Nevin John1, David MacManus1, Sebastien Ourselin2, Sue Pavitt3, Gavin Giovannoni4, Richard Parker5, Chris Weir5, Nigel Stallard6, Clive Hawkins7, Basil Sharrack8, Peter Connick9, Siddharthan Chandran9, Claudia Angela Gandini Wheeler-Kingshott 1,10,11, Frederik Barkhof2,12,13, and Jeremy Chataway1 1Queen Square MS Centre, UCL Institute of Neurology, Faculty of Brain Sciences, University College London, London, United Kingdom, 2Translational Imaging Group (TIG), Centre for Medical Image Computing (CMIC), University College London, London, United Kingdom, 3Leeds Institute of Health Sciences, University of Leeds, Leeds, United Kingdom, 4Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University London, London, United Kingdom, 5Edinburgh Clinical Trials Unit, Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, United Kingdom, 6Statistics and Epidemiology, Division of Health Sciences, Warwick Medical School, University of Warwick, Warwick, United Kingdom, 7Keele University Medical School, Royal Stoke University Hospital, Stoke-on-Trent, United Kingdom, 8Department of Neurology, Royal Hallamshire Hospital, Sheffield, United Kingdom, 9Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom, 10Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy, 11Brain MRI 3T Research Centre, C. Mondino National Neurological Institute, Pavia, Italy, 12National Institute for Health Research (NIHR), University College London Hospitals (UCLH) Biomedical Research Centre (BRC), London, United Kingdom, 13Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, Netherlands We investigated the cross-sectional relationships between thalamic lesions (i.e. total thalamic lesion volume), thalamic volume, and cognitive deficit in 55 subjects with secondary progressive multiple sclerosis. We measured: total intracranial volume, T2 lesion volume (T2LV), thalamic volume, thalamic lesions, and symbol digit modalities test (SDMT). Thalamic lesions inversely correlated with thalamic volume and these two variables were independently associated with cognitive deficit as measured by SDMT. After adjusting for T2LV, thalamic volume was the strongest predictor of cognitive deficit. Thalamic lesions  may have clinical relevance independent of thalamic volume and will be longitudinally investigated in a bigger sample size.

 85 8:51 QSM identifies pro-inflammatory iron-positive MS lesions Kelly Gillen1, Mayyan Mubarak2, Ishan Negi2, Somiah Dahlawi2, Thanh D Nguyen1, David Pitt2, and Yi Wang1 1Radiology, Weill Cornell Medical College, New York, NY, United States, 2Neurology, Yale University, New Haven, CT, United States Multiple sclerosis is an autoimmune disorder whose demyelinated plaques may be connected with elevated iron. We combined quantitative susceptibility mapping (QSM) with histopathological techniques to quantify iron, macrophages/microglia, and pro/anti-inflammatory markers to demonstrate that regions of high susceptibility on QSM correspond to pro-inflammatory iron-positive macrophages/microglia. QSM is therefore a valuable clinical tool to identify smoldering lesions not visible using conventional MRI techniques.

 86 9:03 A longitudinal study of lesion evolution in Multiple Sclerosis using multi-contrast 7T MRI Kingkarn Aphiwatthanasumet1, Olivier Mougin1, Nicolas Geades2, Nikos Evangelou3, Molly Bright3, Richard Bowtell1, and Penny Gowland1 1Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, United Kingdom, 2Philips Healthcare, Mölndal, Sweden, Mölndal, Sweden, 3Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, United Kingdom We use multi-contrast 7T MRI to evaluate longitudinal changes in white matter tissue properties prior to and after lesion appearance. Four MS patients were scanned 6 times at 6-week intervals, and 20 new lesions were identified on FLAIR images in that period. Of these, 35% showed a hypointense rim and 65% showed no rim in QSM data. Subtle changes in MT, NOE, and QSM relative to NAWM values could be detected 6 weeks prior to the first clinical appearance of new lesions. In future studies, these data will provide insight into specific tissue changes that precede lesion development in MS.

 87 9:15 A 3-year follow-up study of enhancing and non-enhancing multiple sclerosis (MS) lesions in MS patients with clinically isolated syndrome (CIS) using a multi-compartment T2 relaxometry (MCT2) model Sudhanya Chatterjee1, Olivier Commowick1, Onur Afacan2, Benoit Combès1, Anne Kerbrat1,3, Simon K Warfield2, and Christian Barillot1 1University of Rennes, INRIA, CNRS, INSERM, IRISA UMR 6074, VISAGES ERL U-1228, F-35000 Rennes, France, Rennes, France, 2CRL, Boston Children’s Hospital, Department of Radiology, 300 Longwood Avenue, WB215, Boston, MA 02115, USA, Boston, MA, United States, 3Department of Neurology, Rennes University Hospital, Rennes, France, Rennes, France Obtaining information on condition of tissue microstructures (such as myelin, intra/extra cellular cells, free water) can provide important insights into MS lesions. However, MRI voxels are heterogeneous in terms of tissue microstructure due to the limited imaging resolution owing to existing physical limitations of MRI scanners. Here we evaluated a multi-compartment T2 relaxometry model and then used it to study the evolution of enhancing (USPIO and gadolinium positive) and non-enhancing lesions in 6 MS patients with CIS characteristics over a period 3 years with 7 follow-up scans after baseline.

 88 9:27 A multi-parametric study of MS lesions Mara Cercignani1,2, Camilla Vizzotto1, Davide Esposito1, Barbara Spano2, Giovanni Giulietti2, and Marco Bozzali1,2 1Department of Neuroscience, Brighton & Sussex Medical School, Brighton, United Kingdom, 2Neuroimaging Laboratory, Santa Lucia Foundation IRCCS, Rome, Italy Counter-intuitively, reduced orientation dispersion has been reported in MS lesions, and confirmed by histology. Here we classify lesional tissue based on its orientation dispersion, and we  compute a series of indices from from diffusion and magnetization transfer MRI to highlight potential differences in the pathological substrate of lesions with reduced vs increased orientation dispersion. We show that lesions with reduced dispersion are more likely to show extensive demyelination and axonal loss.

 89 9:39 The Age effect on Multi-parametric Magnetic Resonance Imaging changes in Multiple Sclerosis lesions Elda Fischi-Gomez1,2, Mário João Fartaria2,3,4, Guillaume Bonnier1, and Cristina Granziera1,5 1Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States, 2Signal Processing Laboratory (LTS 5), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland, 3Advanced Clinical Imaging Technology, Siemens Healthcare AG, Lausanne, Switzerland, 4Department of Radiology, Centre Hospitalier Universitaire Vaudois (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland, 5Neurology Department and Neuroimaging Laboratory, Basel University Hospital, Basel, Switzerland We assessed the effect of age on the longitudinal evolution of intralesional neurite density and orientation dispersion indices, magnetization transfer ratio and T1 relaxometry in a cohort of relapsing-remitting MS patients. While we observed a decrease of neurite dispersion in lesions and stable neurite density, MTR and qT1, age did not seem to influence those longitudinal changes in MS lesions.

 90 9:51 Linking macrostructural and microstructural damage in early MS: a geostatistical and diffusion MRI study Carmen Tur1, Robert Marschallinger2,3, Ferran Prados1,4, Sara Collorone1, Daniel R Altmann1,5, Sébastien Ourselin4, Claudia Angela Gandini Wheeler-Kingshott1,6,7, and Olga Ciccarelli1 1Queen Square MS Centre. Neuroinflammation department. UCL Institute of Neurology, University College London, London, United Kingdom, 2Department of Geoinformatics - Z_GIS, Salzburg University, Salzburg, Austria, 3Department of Neurology, Christian Doppler Medical Center, Paracelsus Medical University, Salzburg, Austria, 4Translational Imaging Group, CMIC, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom, 5Department of Medical Statistics, London School of Hygiene and Tropical Medicine, University of London, London, United Kingdom, 6Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy, 7Brain MRI 3T Research Centre, C. Mondino National Neurological Institute, Pavia, Italy Macroscopic white matter (WM) lesion volume has been extensively used to predict disability progression in multiple sclerosis (MS). However, currently used lesion-related metrics fail to capture the complexity of WM-lesion spatial distribution. Here we used geostatistics, an emerging approach to model spatial data projected onto a common coordinate space, to characterise the spatial distributional features of WM lesions of patients with their first MS attack, the clinical relevance of lesion distributional properties and their microstructural correlates, through diffusion MRI. We conclude that WM-lesion spatial distributional features reveal novel aspects of MS pathology, are clinically relevant and possess specific microstructural features.

 91 10:03 The relevance of cortical lesions in cortical thinning in multiple sclerosis by ultra-high field MRI Constantina Andrada Treaba1,2, Elena Herranz1,2, Russell Ouellette IV1, Tobias Granberg1,2,3,4, Celine Louapre1,2, Valeria Barletta1,2, Ambica Mehndiratta1, Jacob A Sloane2,5, Revere Kinkel6, and Caterina Mainero1,2 1Department of Radiology, A.A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, United States, 2Harvard Medical School, Boston, MA, United States, 3Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden, 4Department of Radiology, Karolinska University Hospital, Stockholm, Sweden, 5Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, United States, 6Department of Neurosciences, University of California, San Diego, CA, United States Cortical lesions (CL) and cortical atrophy are frequent in multiple sclerosis (MS) and main determinants of disease progression. The relationship between them is still unknown, mostly due to the low sensitivity of clinical magnetic resonance imaging (MRI) to CL. Disconnection from white matter (WM) lesions has also been proposed as a pathogenic mechanism for cortical MS atrophy. Using 7 Tesla MRI that has shown increased sensitivity to CL than clinical MRI, we showed, in a large MS cohort that WM lesions are the main determinant of cortical thinning. Nevertheless, CL resulted as the main contributors of physical and cognitive disability.

Oral

### Breast

 W03/04 Monday 8:15 - 10:15 Moderators: Ileana Hancu & Savannah Partridge

 92 8:15 The role of diffusion-weighted MRI in the prediction of response in I-SPY 2 TRIAL Wen Li1, Lisa J Wilmes1, David C Newitt1, John Kornak2, Ella F Jones1, Savannah C Partridge3, Jessica Gibbs1, Bo La Yun1, Matthew S Tanaka1, Laura J Esserman4, and Nola M Hylton1 1Radiology & Biomedical Imaging, UCSF, San Francisco, CA, United States, 2Epidemiology and Biostatistics, UCSF, San Francisco, CA, United States, 3School of Medicine, University of Washington, Seattle, WA, United States, 4Surgery and Radiology, UCSF, San Francisco, CA, United States Diffusion weighted MRI can be used to characterize water mobility and cellularity of tumor by measuring the apparent diffusion coefficient (ADC). Functional tumor volume (FTV) measures size change along the treatment. This study showed that after only 3 weeks of pre-surgery chemotherapy, ADC added value to the logistic regression model of using FTV alone to predict pCR or RCB as outcomes for patients with advanced breast cancer in I-SPY 2 TRIAL. The effect of adding ADC is statistically significant and increase the estimated area under the ROC curve after adjusted for breast cancer subtype categorized by HR and HER2 status.

 93 8:27 ACRIN 6702 DWI Trial: The Value of Alternate ADC Metrics Compared to Standard ADC for Decreasing Breast MRI False-Positives Habib Rahbar1, Zheng Zhang2, Justin Romanoff2, Lucy G Hanna2, Christopher E. Comstock3, and Savannah C Partridge1 1Radiology, University of Washington, Seattle, WA, United States, 2ACRIN Biostatistics Center, Brown University, Providence, RI, United States, 3Memorial Sloan Kettering Cancer Center, New York, NY, United States The ACRIN 6702 trial confirmed that standard ADCs from multi b-value DWI acquisition are lower in malignancies than in benign lesions and that application of standard ADCs can eliminate one in five unnecessary biopsies. Secondary analysis from this trial demonstrated that application of alternate ADC metrics, including perfusion insensitive ADCØ and normalized ADC provide no practical benefit over standard ADC for improving conventional DCE-MRI performance. These findings suggest that standard ADC calculations alone are sufficient for improving breast MRI specificity and should be the primary metric included in the next edition of the BI-RADS atlas.

 94 8:39 DCE-MRI based radiomics signature: a potential biomarker for preoperative prediction of sentinel lymph node metastasis in breast cancer Jie Ding1, Chunling Liu2, Karl Spuhler1, Tim Duong3, Changhong Liang2, Shahid Hussain3, and Chuan Huang1,3,4,5 1Biomedical Engineering, Stony Brook University, Stony Brook, NY, United States, 2Radiology, Guangdong General Hospital/Guangdong Academy of Medical Sciences, Guangzhou, China, 3Radiology, Stony Brook Medicine, Stony Brook, NY, United States, 4Computer Science, Stony Brook University, Stony Brook, NY, United States, 5Psychiatry, Stony Brook Medicine, Stony Brook, NY, United States This study is the first to combine DCE-MRI radiomics with clinical information to predict sentinel lymph node (SLN) metastasis in breast cancer. The prediction model was established in a training set, and was further validated in a completely independent validation set, with AUC of 0.898 and negative predictive value of 0.902. This prediction performance surpasses the previous study using T2w and DWI, and is particularly useful for eliminating the unnecessary, invasive SLN biopsy and axillary dissection in patients with negative SLN, offering a step towards precision medicine of breast cancer.

 95 8:51 Multi-compartmental sodium quantification in breast using a bilateral dual-tuned proton/sodium coil and multi-pulse excitation scheme at 7T Carlotta Ianniello1,2, Guillaume Madelin1, and Ryan Brown1 1Center for Advanced Imaging Innovation and Research (CAI2R) and Center for Biomedical Imaging, New York, NY, United States, 2The Sackler Institute of Graduate Biomedical Science, New York University School of Medicine, New York, NY, United States Sodium is an important electrolyte in the human body and is a distinct MRI contrast mechanism in breast cancer as it provides insight on cellular viability, ion homeostasis, inflammation, and fluid content. Due to sodium low SNR, intracellular sodium concentration (C1), volume fractions for the intracellular (α1) or extracellular compartments (α2), and fluid (α3) remain largely unexplored. We built a custom bilateral dual-tuned 1H/23Na RF coil and developed a novel fingerprinting-based sodium excitation scheme on a 7T system to enable multi-compartmental sodium quantification in breast. In this work we describe the coil, pulse sequence and preliminary results in one subject.

 96 9:03 CEST MRI – a potential tool for breast cancer grade and proliferation rate differentiation Olgica Zaric1, Alex Farr2, Esau Poblador Rodriguez1, Vladimir Mlynarik1, Claudia Kronnerwetter1, Benjamin Schmitt3, Wolfgang Bogner1, Christian Singer2, and Siegfried Trattnig1 1High Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria, 2Department of Obstetrics and Gynecology, Medical University of Vienna, Vienna, Austria, 3Siemens Healthineers, Sydney, Australia I this study, we investigated which CEST contrast changes are characteristic and dominant for breast malignancies. In 18 female patients, we performed DWI, CEST imaging, and T1-CE MRI. Significant differences in MTRasym between G1 and G3 was found (P= 0.007). Between G1 and G2 (P=0.066) as well as between G2 and G3 no difference were observed (P= 0.089). Correlation test demonstrated a strong positive correlation between mean MTRasym measured in region of its maximum and proliferation factor, Ki-67 (r=0.890, P˂0.001). This preliminary results show that CEST-MRI of the breast has a potential to provide information regarding the tumor histological features.

 97 9:15 ACRIN 6702 Multisite Breast DWI Trial: Comparison of Site vs. Centralized ADC Measures and Factors Affecting Data Quality Savannah C Partridge1, Zheng Zhang2, Jennifer Whisenant3, Averi E Kitsch1, Justin Romanoff2, Habib Rahbar1, Thomas Yankeelov4, and Thomas L Chenevert5 1Radiology, University of Washington, Seattle, WA, United States, 2ACRIN Biostatistics Center, Brown University, Providence, RI, United States, 3Hematology/Oncology, Vanderbilt University, Nashville, TN, United States, 4Biomedical Engineering, University of Texas, Austin, TX, United States, 5Radiology, University of Michigan, Ann Arbor, MI, United States Diffusion-weighted imaging (DWI) shows potential to improve lesion characterization and diagnostic performance of conventional contrast-enhanced breast MRI. Promising preliminary data from the ACRIN 6702 multisite trial show that DWI can reduce false-positive breast MRIs. Comparison of independently performed site and centrally-measured ADC values showed reasonable agreement, but suggest that further standardization of DWI interpretation and analysis tools across sites could improve diagnostic performance. Results also show more work is needed to address image quality issues and increase utility for measuring ADC values in MRI-detected breast lesions.

 98 9:27 Radiomics with magnetic resonance imaging of the breast for early prediction of response to neo-adjuvant chemotherapy in breast cancer patients Katja Pinker-Domenig1, Amirhessam Tahmassebi2, Georg Wengert3, Thomas H Helbich3, Zsuzsanne Bago-Horvath4, Sousan Akaei4, Elisabeth A Morris1, and Anke Meyer-Baese2 1Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, United States, 2Department of Scientific Computing, Florida State University, Tallahassee, FL, United States, 3Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria, 4Department of Pathology, Medical University of Vienna, Vienna, Austria Breast cancer patients that achieve pCR after NAC have a significantly improved DFS and OS. The aim of this study was to assess radiomics with multiparametric MRI using DCE and T2w imaging for the early prediction of pCR to NAC in breast cancer patients. In 41 women radiomics analysis of MRI data was performed. Histopathology using the Residual Cancer Burden (RCB) score and class were the standard of reference. Radiomics analysis of MRI achieved AUCs for RCB score (AUC 0.85), metastases (AUC 0.87) and death (AUC 0.92). Radiomics with multiparametric MRI enables prediction of response to NAC with high accuracy.

 99 9:39 Ultrafast Dynamic Contrast Enhanced MRI of the Breast Using DISCO: Are the Quantitative Parameters Helpful in Differentiating between BI-RADS 4 and 5 Subcentimeter Invasive Carcinomas and Benign Lesions? Natsuko Onishi1, Meredith Sadinski1, Katherine M. Gallagher1,2, Brittany Z. Dashevsky1,3, Theodore M. Hunt1, Blanca Bernard-Davila1, Danny F. Martinez1, Amita Shukla-Dave1,4, Elizabeth A. Morris1, and Elizabeth J. Sutton1 1Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, United States, 2Lenox Hill Radiology, New York, NY, United States, 3Department of Radiology & Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States, 4Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, United States The quantitative parameters derived from ultrafast dynamic contrast enhanced (UF-DCE) breast MRI using DISCO were analyzed for the assessment of possible utility in the differentiation between subcentimeter invasive carcinoma and benign lesions. Of all these parameters (MS, CER, IAUGC, BAT and Ktrans), BAT was the only parameter that predicted subcentimeter invasive carcinoma. We believe the significantly shorter BAT for subcentimeter invasive carcinomas is congruent with the known pathophysiology of cancer and may reflect its increased vascularity or shunt formation. BAT can be a complementary parameter to conventional steady-state DCE MRI, which could further stratify subcentimeter BI-RADS 4 and 5 lesions.

 100 9:51 Lymph node multi-parametric MRI characteristics of responders and non-responders of neoadjuvant chemotherapy Renee F. Cattell1,2, James J. Kang1, Silu Han1,2, Thomas Ren1, Pauline B. Huang1, Haifang Li1, Jules A. Cohen3, Paul Fisher1, Roxanne Palermo1, and Tim Q. Duong1 1Department of Radiology, Stony Brook University, Stony Brook, NY, United States, 2Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, United States, 3Department of Medicine, Stony Brook University, Stony Brook, NY, United States In the I-SPY 1 breast cancer clinical trial, change in size of the primary in-breast tumor in response to neoadjuvant therapy was a strong predictor of pathologic complete response. In this study, I-SPY 1 MRI lymph node characteristics was studied. Lymph nodes of patients who achieved pathologic complete response after chemotherapy had different characteristics from those who have residual disease in the tumor bed. The percent change of the signal enhancement ratio of each individual lymph node was the best parameter to differentiate between pathologic complete responders versus incomplete or non-responders.

 101 10:03 Evaluation of microstructure heterogeneity from diffusion q-space imaging (QSI), diffusion weighted imaging (DWI) and non-Gaussian diffusion models in whole breast tumour Nicholas Senn1, Yazan Masannat2,3, Ehab Husain3,4, Bernard Siow5, Steven D Heys2,3, and Jiabao He1 1Aberdeen Biomedical Imaging Centre, University of Aberdeen, Aberdeen, United Kingdom, 2Breast Unit, Aberdeen Royal Infirmary, Aberdeen, United Kingdom, 3School of Medicine, University of Aberdeen, Aberdeen, United Kingdom, 4Pathology Department, Aberdeen Royal Infirmary, Aberdeen, United Kingdom, 5Francis Crick Institute, London, United Kingdom QSI was compared against conventional DWI and non-Gaussian diffusion models, namely diffusion kurtosis imaging (DKI) and stretched-exponential model (SEM) to evaluate diffusivity heterogeneity for profiling breast tumour cell diversity. We investigated whole breast tumours excised from surgery, with imaging performed overnight on the same day on a clinical system. Asymmetry in diffusivity distribution was quantified as histogram skewness, median and 25th-percentile. Correlation analysis was performed to compare QSI against other models. The skewness of diffusivity distribution derived from QSI was the highest among the models and provided a wider spread of values across cohort, allowing more sensitive clinical applications.

Study Groups

 W07 Monday 9:15 - 10:15 (no CME credit)

Study Groups

 W08 Monday 9:15 - 10:15 (no CME credit)

Plenary Session

### Cardiovascular Imaging: From Structure to Function

Organizers: James Carr, Tim Leiner, Reza Nezafat, Bernd Wintersperger, Jennifer Keegan, Sebastian Kozerke, Winfried Willinek

 Plenary Hall (Paris Room) Monday 10:30 - 12:15 Moderators: James Carr & Reza Nezafat

 10:30 ISMRM & ESMRMB Awards

 11:15 Tissue Characterization in the Human Heart Raymond Kwong1 1Brigham & Women's Hospital, United States

 11:35 Current & Emerging Techniques for Evaluating Cardiac Function Sergio Uribe Arancibia1 1Pontificia Universidad Catolica de Chile, Chile

 11:55 Putting it All Altogether: What is the Clinical Impact? Marianna Fontana1 1University College London

Event

### Gold Corporate Symposium: Philips Healthcare

 Plenary Hall (Paris Room) Monday 12:30 - 13:30 (no CME credit)

Electronic YIA Poster

### Electronic Poster: Young Investigator Awards

 Exhibition Hall Monday 13:45 - 15:45 (no CME credit)

 66 13:45 Arterial-Spin-Labeling (ASL) perfusion MRI predicts cognitive function in elderly individuals: a four-year longitudinal study Jill B De Vis1, Shin-Lei Peng2, Xi Chen3, Yang Li1, Peiying Liu1, Sandeepa Sur1, Karen M Rodrigue3, Denise C Park3, and Hanzhang Lu1 1MR Research, Johns Hopkins University, Baltimore, MD, United States, 2Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan, 3Center for Vital Longevity, School of Behavioral and Brain Sciences, University of Texas, Dallas, TX, United States Identification of biomarkers that can predict cognitive decline is of utmost importance for advance in dementia pharmacotherapy. In this study, cerebral blood flow (CBF) is investigated as a predictor for cognitive decline in a healthy aging population. We found CBF in the frontal lobe to be most predictive for cognitive decline, specifically for episodic memory and in the older population. This suggest that CBF can be used as a biomarker to identify subjects susceptible to cognitive decline, to identify suitable cohorts for clinical trials, and to monitor the effects of pharmacotherapy.

 67 14:05 Measuring human placental blood flow with multi-delay 3D GRASE pseudo-continuous arterial spin labeling at 3 Tesla Xingfeng Shao1, Dapeng Liu2, Thomas Martin2, Teresa Chanlaw3, Sherin U. Devaskar3, Carla Janzen4, Aisling M. Murphy4, Daniel Margolis2, Kyunghyun Sung2, and Danny J.J. Wang1 1Laboratory of FMRI Technology (LOFT), Mark & Mary Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States, 2Department of Radiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States, 3Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States, 4Department of Obstetrics and Gynecology, Division of Maternal Fetal Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States Placenta influences the health of both a woman and her fetus during pregnancy. Maternal blood supply to placenta can be measured non-invasively using arterial spin labeling (ASL). The purpose of this study is to present a multi-delay pseudo-continuous arterial spin labeling (pCASL) combined with a fast 3D inner-volume gradient- and spin-echo (GRASE) imaging technique to simultaneously measure placental blood flow (PBF) and arterial transit time (ATT), and to study PBF and ATT evolution with gestational age during the second trimester. The PBF values were compared with uterine arterial Doppler ultrasound to assess its potential clinical utility.

 68 14:25 Reverse double inversion-recovery: improving motion robustness of cardiac T2-weighted dark-blood turbo spin-echo sequence Chenxi Hu1, Steffen Huber1, Syed R Latif2, Guido Santacana-Laffitte1, Hamid R Mojibian1, Lauren Baldassarre2, and Dana C Peters1 1Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, United States, 2Department of Internal Medicine, Section of Cardiovascular Medicine, Yale School of Medicine, New Haven, CT, United States The cardiac T2-weighted dark-blood turbo spin-echo (TSE) sequence based on double inversion-recovery (DIR) is subject to motion artifacts due to mismatching of slices from the dark-blood preparation and the TSE readout. Here we propose reverse double inversion-recovery (RDIR), which performs the slice-selective inversion of the DIR preparation in the same cardiac phase as the TSE readout to minimize the slice mismatching. RDIR was evaluated in healthy subjects and patients. Results show that RDIR-TSE achieved a significantly improved image quality in the right ventricle and an improved image quality in the left ventricle compared to the standard DIR-TSE.

 69 14:45 Phase-encoded xSPEN: A novel high-resolution volumetric alternative to RARE MRI Zhiyong Zhang1, Michael Lustig2, and Lucio Frydman1 1Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel, 2Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, CA, United States We have recently introduced cross-term SPatiotemporal ENcoding (xSPEN), a technique with exceptional resilience to field heterogeneities. This study explores a multi-scan extension of xSPEN, which simultaneously yields ky/kz data containing low and high frequency components as well as transposed low-resolution z/y images, with unique downsampling characteristics. A reconstruction scheme converting this information into high resolution 3D images with fully multiplexed volumetric coverage is introduced. The Results provide a series of high-resolution multiscan xSPEN imaging examples and analyzes their sensitivity vis-a-vis commonly used 2D RARE and multi-slab 3D RARE MRI techniques.

 70 15:05 Prospective motion correction with NMR markers using only native sequence elements Alexander Aranovitch1, Maximilian Haeberlin1, Simon Gross1, Benjamin E Dietrich1, Bertram J Wilm1, David O Brunner1, Thomas Schmid1, Roger Luechinger1, and Klaas P Pruessmann1 1Institute for Biomedical Engineering, ETH Zurich and University of Zurich, Zurich, Switzerland A new method for tracking active NMR markers is presented. It requires no alterations of the MR sequence and can be used for prospective motion correction (PMC) in brain MRI. The proposed method collects high-frequency information present due to gradient switching from multiple short, temporally separated snippets within one or more TR of the given sequence. A tracking precision on the order of 10µm and 0.01° (RMS) for translational and rotational degrees of freedom is obtained. The method is demonstrated in-vivo with high-resolution 2D T2*-weighted GRE and 3D MPRAGE brain scans.

 71 15:25 Learning a Variational Network for Reconstruction of Accelerated MRI Data Kerstin Hammernik1,2, Erich Kobler1, Teresa Klatzer1, Michael P Recht2, Daniel K Sodickson2, Thomas Pock1,3, and Florian Knoll2 1Institute of Computer Graphics and Vision, Graz University of Technology, Graz, Austria, 2Center for Biomedical Imaging and Center for Advanced Imaging Innovation and Research (CAI2R), Department of Radiology, NYU School of Medicine, New York, NY, United States, 3Safety & Security Department, AIT Austrian Institute of Technology GmbH, Vienna, Austria In this work, we propose variational networks for fast and high-quality reconstruction of accelerated multi-coil MR data. A wide range of experiments and a dedicated user study on clinical patient data show that the proposed variational network reconstructions outperform traditional reconstruction approaches in terms of image quality and residual artifacts. Additionally, variational networks offer high reconstruction speed, which is substantial for the incorporation into clinical workflow.

 Exhibition Hall 1451-1475 Monday 13:45 - 15:45 (no CME credit)

 Exhibition Hall 1476-1508 Monday 13:45 - 15:45 (no CME credit)

Electronic Poster: Cardiovascular

 Exhibition Hall Monday 13:45 - 14:45 (no CME credit)

Electronic Poster: Acquisition, Reconstruction & Analysis

 Exhibition Hall Monday 13:45 - 14:45 (no CME credit)

Study Groups

### High Field Systems & Applications Business Meeting

 W07 Monday 13:45 - 14:45 (no CME credit)

Study Groups

### Hyperpolarisation Methods & Equipment Business Meeting

 W08 Monday 13:45 - 14:45 (no CME credit)

Member-Initiated Symposium

### Non-Invasive Axon Diameter Mapping: So Fascinating, So Challenging & So Many Questions

Organizers: Muhamed Barakovic, Alessandro Daducci, Tim Dyrby

 S05 Monday 13:45 - 15:45 Moderators: Ileana Jelescu & Muhamed Barakovic (no CME credit)

 13:45 Developmental & Computational Properties of Axons Giorgio Innocenti

 14:05 Diffusion MRI Techniques for Mapping Axon Diameter: Can We Image Axon Diameter in the Brain? Andrada Ianus1 1University College London, United Kingdom

 14:25 Axon Diameter Mapping with q-t MRI: Is It the Inner or the Outer? Els Fieremans Fieremans1 1Radiology, New York University School of Medicine, New York, NY, United States

 14:45 The Effect of Axon Diameter on High Temporal Resolution Functional Data Samuel Deslauriers-Gauthier

 15:05 Axons, Axons, So Many Axons … What Do We Really Need to Measure? Derek Jones1 1CUBRIC, School of Psychology, United Kingdom

 15:25 Discussion

Member-Initiated Symposium

### Zooming into the "Little Brain": Advances in Cerebellar Imaging

Organizers: Pierre-Louis Bazin, Wietske van der Zwaag

 W05/06 Monday 13:45 - 15:45 Moderators: Pierre-Louis Bazin & Wietske van der Zwaag (no CME credit)

 13:45 Cerebellar Lobular Structure & Connectional Architecture Christopher Steele1 1Max Planck Institute

 14:15 Structural & Functional MRI of the Human Cerebellar Nuclei Dagmar Timmann

 14:45 Insights into Cerebellar Microstructure from Diffusion in Many Dimensions Henrik Lundell1 1DRCMR, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark

 15:15 Cerebellar Structural & Functional Abnormalities in Multiple Sclerosis Cristina Granziera

Weekday Course

### Machine Learning in Cardiovascular Disease

Organizers: Sebastian Kozerke, Tim Leiner, Reza Nezafat

 N02 Monday 13:45 - 15:45 Moderators: Sebastian Kozerke & Tim Leiner

 13:45 Nuts & Bolts of Machine Learning Daniel Rueckert1 1Imperial College London, United Kingdom This talk will give an overview of machine learning techniques for medical image analysis. We will describe both supervised and supervised machine learning approaches. A particular focus will be on deep learning approaches, including Convolutional Neural Networks (CNN) and how these can be used in cardiovascular MR imaging. We will demonstrate machine learning applications for the fast reconstruction of cardiac MR images from undersampled k-space data, image super-resolution as well segmentation of the cardiovascular anatomy in cine cardiac MRI.

 14:15 Role of Machine Learning in Image Acquisition & Reconstruction Kerstin Hammernik1,2 1Institute of Computer Vision and Graphics, Graz University of Technology, Austria, 2Center for Biomedical Imaging, New York University School of Medicine, New York, NY, United States In this educational, we give an overview how deep learning is currently used in static and dynamic  MRI reconstruction of undersampled k-space data. While we observe large improvements in terms of image quality and artifact removal for learning-based approaches compared to traditional approaches, we have to consider also several challenges. We will discuss both advantages and challenges using examples of current deep learning-based approaches for reconstruction of undersampled k-space data, focusing on the design of network architectures and loss functions.

 14:45 Machine Learning: A Clinical Perspective on CV Disease Bharath Ambale Venkatesh1 1Johns Hopkins University, United States Machine learning methods are better suited for meaningful risk prediction in extensively phenotyped large-scale epidemiological studies than traditional methods or risk scores. This strategy could yield insights about specific use of variables for specific event prediction and guiding strategies to prevent cardiovascular disease outcomes. Potentially, these techniques could be applied retrospectively to analyze large data sets for identifying disease mechanisms, and as a means of hypothesis generation, without prior assumptions.

 15:15 Will ML Replace Radiologists? Declan O'Regan In this presentation the current state of the art of Machine Learning in medical image analysis will be discussed and what impact this may have on the role of clinical radiologists.

 15:45 Adjournment & Meet the Teachers

Weekday Course

### MRI Value in Body Imaging: Role for Abbreviated Protocols?

Organizers: Kathryn Fowler, Catherine Hines, Kartik Jhaveri, Lorenzo Mannelli, Valeria Panebianco, Scott Reeder, Reiko Woodhams

 S01 Monday 13:45 - 15:45 Moderators: Thomas Hope & Ihab Kamel

 13:45 Liver Fat, Iron, & Fibrosis Abbreviated Protocols Sudhakar K Venkatesh1 1Radiology, Mayo Clinic, Rochester, MN, United States With the emergence of non-alcoholic fatty liver disease (NAFLD) as most common chronic liver disease, detection and quantification of liver fat and fibrosis becomes important. Iron overload frequently seen in association with fatty liver and liver fibrosis. Noninvasive quantification of liver fat, iron and fibrosis with MRI is now considered the standard for diagnosis and monitoring. In this presentation, typical clinical scenarios that requires MRI abbreviated protocol for liver fat, iron and fibrosis quantification, candidate sequences and multi-parametric MRI protocols will be discussed. MRI protocols will be illustrated with clinical examples and limitations  will be highlighted.

 14:09 Liver Screening & Surveillance-HCC Bachir Taouli1 1Mount Sinai School of Medicine, United States In this presentation, we will discuss the different scenarios in which AMRI can be used: 1) in the context of cancer screening or diagnosis (liver cancer, liver metastases, prostate cancer); 2) for liver health assessment (fat, fibrosis and iron), 3) in cases of contra-indications to gadolinium contrast. We will discuss the current evidence on the use of AMRI, cost savings, limitations and future directions.

 14:33 Screening the High-Risk Pancreas Giovanni Morana1 1Radiological Department, General Hospital Ca' Foncello, Treviso, Italy MRI is an imaging method useful in screening high risk patients for pancreatic cancer

 14:57 Active Surveillance in Managing Prostate Cancer Katarzyna J. Macura1 1Radiology, Johns Hopkins University, Baltimore, MD, United States Active surveillance (AS) has emerged as an important management strategy to avoid overtreatment of low-risk indolent prostate cancer and MRI of the prostate has been documented to offer high accuracy for the detection and localization of clinically significant cancer with high negative predictive value. The main role of MRI in AS is in patient selection and monitoring with a potential to minimize the invasiveness of follow-up. Abbreviated prostate MRI protocols offer a diagnostic accuracy and cancer detection rates that are equivalent to those of conventional full multiparametric MRIs.

 15:21 Breast Cancer Screening Savannah Partridge1 1University of Washington, United States Abbreviated breast MRI protocols hold potential to reduce time and overall costs of breast MRI examinations, which could increase accessibility for more widespread screening. A growing number of studies have demonstrated that abbreviated MRI protocols can provide comparable diagnostic accuracy to that of conventional full MRI protocols for breast cancer screening. Current approaches and performance results will be reviewed, along with discussion of future directions.

 15:45 Adjournment & Meet the Teachers

Power Pitch

### Pitch: Molecular & Metabolic Imaging

 Power Pitch Theater A - Exhibition Hall Monday 13:45 - 14:45 Moderators: Amnon Bar-Shir & Marion Menzel (no CME credit)

 102 13:45 A novel iterative sparse deconvolution method for multicolor 19F-MRI Jasper Schoormans1, Claudia Calcagno2, Mariah Daal1, Christopher Faries2, Brenda L Sanchez-Gaytan2, Aart J Nederveen3, Zahi A Fayad2, Willem J M Mulder2, Bram F Coolen1, and Gustav J Strijkers1,2 1Department of Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, Netherlands, 2Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 3Department of Radiology, Academic Medical Center, Amsterdam, Netherlands

 103 13:45 Multimodal Assessment of Orbital Immune Cell Infiltration and Tissue Remodeling During Development of Graves’ Disease by 1H/19F MRI Ulrich Flögel1, Anke Schlüter2, Christoph Jacoby1, Sebastian Temme1, J Paul Benga2, Anja Eckstein2, Jürgen Schrader1, and Utta Berchner-Pfannschmidt2 1Experimental Cardiovascular Imaging, Heinrich Heine University, Düsseldorf, Germany, 2University of Essen, Essen, Germany

 104 13:45 Hyperpolarized Xe-129 Imaging of Pluripotent Stem Cell-Derived Alveolar-Like Macrophages in the Lungs: Proof-of-Concept Study Using Superparamagnetic Iron-Oxide Nanoparticles Vlora Riberdy1,2, Michael Litvack2, Elaine Stirrat2, Marcus Couch2, Martin Post2, and Giles Santyr1,2 1Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada, 2Translational Medicine, The Hospital for Sick Children, Toronto, ON, Canada

 105 13:45 In Vivo Molecular Imaging of MUC1-Expressing Colorectal Tumors Using Targeted Hyperpolarized Silicon Particles Nicholas Whiting1,2, Jingzhe Hu1,3, Shivanand Pudakalakatti1, Caitlin McCowan1,3, Daniel Carson3, Jennifer Davis1, Niki Millward1, David Menter1, Pamela Constantinou3, and Pratip Bhattacharya1 1The University of Texas MD Anderson Cancer Center, Houston, TX, United States, 2Rowan University, Glassboro, NJ, United States, 3Rice University, Houston, TX, United States

 106 13:45 Imaging glutathione depletion in the rat brain using ascorbate-derived hyperpolarized MR and PET probes Hecong Qin1,2, Valerie Carroll1, Renuka Sriram1, Cornelius von Morze1, Zhen Jane Wang1, Christopher Mutch1, Kayvan R. Keshari3, Robert R. Flavell1, John Kurhanewciz1,2, and David M. Wilson1 1Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States, 2UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley and San Francisco, CA, United States, 3Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, United States

 107 13:45 In-vivo metabolism of co-hyperpolarized [1-13C] pyruvate and [1,3-13C] acetoacetate identifies cytosolic and mitochondrial redox in ischemic perfused hearts Gaurav Sharma1, Craig R. Malloy1,2,3, A. Dean Sherry1,2,4, and Chalermchai Khemtong1,2 1Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States, 2Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, United States, 3Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, United States, 4Department of Chemistry, University of Texas at Dallas, Dallas, TX, United States

 108 13:45 Probing perturbed hepatic metabolism in bile-duct-ligated rats with hyperpolarized 13C pyruvate and arginine Hikari A. I. Yoshihara1, Dmitri Firsov2, Cristina Cudalbu3, and Rolf Gruetter4 1Laboratory for Functional and Metabolic Imaging, Swiss Federal Institute of Technology, Lausanne (EPFL), Lausanne, Switzerland, 2Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland, 3Centre d'Imagerie Biomedicale (CIBM), Swiss Federal Institute of Technology, Lausanne (EPFL), Lausanne, Switzerland, 4Laboratory for Functional and Metabolic Imaging & Centre d'Imagerie Biomedicale (CIBM), Swiss Federal Institute of Technology, Lausanne (EPFL), Lausanne, Switzerland

 109 13:45 Hollow Manganese-Silicate (HMS) Nanoparticles as a Liver Specific MRI contrast agent Moon-Sun Jang1, Jin Goo Kim2, Geun Ho Im1, Jung Hee Lee1,3, Won Jae Lee1, and In Su Lee2 1Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea, 2National Creative Research Initiative Center for Nanospace-confined Chemical Reactions and Department of Chemistry, Pohang University of Science and Technology (POSTECH), Gyeongbuk, Republic of Korea, 3Departments of Health Science and Technology and Medical Device Management and Research, Samsung Advanced Institute for Health Science and Technology, Sungkyunkwan University, Seoul, Republic of Korea

 110 13:45 Magnetic Resonance Temperature Imaging for Nanoparticle-Mediated Tumor Photothermal Therapy Fu Guifeng1,2, Guo Jianxin1, Wei Xiaocheng3, Zhang Fan2, and Yang Jian1 1Medical Imaging Department, First Affiliated Hospital of Xi'an Jiaotong University, Xi’an, China, 2Center for Molecular Imaging and Translational Medicine, Xiamen University, Xiamen, China, 3MR Research China, GE Healthcare, Beijing, China

 111 13:45 Amide proton transfer-weighted imaging in meningioma: Prediction of tumor grade, histologic subtype and association with Ki-67 proliferation status Hao Yu1, Xianlong Wang1, Qihong Rui1, Shanshan Jiang2, Jinyuan Zhou2, and Zhibo Wen1 1Department of Radiology, Zhujiang Hospital of Southern Medical University, Guangzhou, China, 2Division of MR Research, Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States

 112 13:45 Brown Adipose Tissue Mass Measurement by Z-Spectrum Imaging Alessandro M Scotti1,2,3, Rongwen Tain1,3, Weiguo Li1,4,5, Victoria Gil6, Chong Wee Liew6, and Kejia Cai1,3 1Radiology, University of Illinois, Chicago, IL, United States, 2Bioengineering, University of Illinois at Chicago, Chicago, IL, United States, 3Center for MR Research, University of Illinois at Chicago, Chicago, IL, United States, 4Research Resource Center, University of Illinois at Chicago, Chicago, IL, United States, 5Radiology, Northwestern University, Chicago, IL, United States, 6Physiology and Biophysics, University of Illinois, Chicago, IL, United States

 113 13:45 Carbon Nanodots as Diamagnetic CEST MRI Contrast Agents for Cell Labeling Jia Zhang1, Minling Gao2,3, Yue Yuan1,4, Yuguo Li1, Peter van Zijl1,5, Mingyao Ying2,3, and Guanshu Liu1,5 1Department of Radiology and Radiological Science, Johns Hopkins University, School of Medicine, Baltimore, MD, United States, 2Department of Neurology, Johns Hopkins University, School of Medicine, Baltimore, MD, United States, 3Kennedy Krieger Institute, Baltimore, MD, United States, 4Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, MD, United States, 5F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States

 114 13:45 Correlation of tissue pH via 31P-MRSI with MTRasym derived from APT-CEST-MRI in glioblastoma and normal appearing white matter Jan Rüdiger Schüre1, Stella Breuer1, Manoj Shrestha2, Ralf Deichmann2, Marlies Wagner1, and Ulrich Pilatus1 1Neuroradiology, University Hospital Frankfurt, Frankfurt am Main, Germany, 2Brain Imaging Center, Goethe University Frankfurt, Frankfurt am Main, Germany

 115 13:45 Imaging vascular inflammation as a marker for T-cell infiltration in preclinical tumor models. Johannes Riegler1, Vincent Javinal2, Maj Hedehus1, Jill Schartner2, and Richard A.D. Carano1 1Biomedical Imaging, Genentech, South San Francisco, CA, United States, 2Genentech, South San Francisco, CA, United States

 116 13:45 Translational Radiogenomics of Brain Tumors: From Lab-Invesigation to Clinical Application Dieter Henrik Heiland1, Horst Urbach2, and Irina Mader3 1Department of Neurosurgery, Medical Center Freiburg, Freiburg, Germany, 2Department of Nueroradiology, Medical Center Freibrurg, Freibrurg, Germany, 3Medical Center Freiburg, Freiburg, Germany

Power Pitch

### Pitch: MRI in Cancer Therapy & Diagnostics

 Power Pitch Theater B - Exhibition Hall Monday 13:45 - 14:45 Moderators: Pek Lan Khong & Irene Marco-Rius (no CME credit)

 117 13:45 MRI-only Treatment Planning using Pseudo CT Generation from Deep Learning Approach Fang Liu1, Poonam Yadav2, Andrew M Baschnagel2, and Alan McMillan1 1Department of Radiology, University of Wisconsin-Madison, Madison, WI, United States, 2Department of Human Oncology, University of Wisconsin-Madison, Madison, WI, United States

 118 13:45 Online Super-resolution 4D T2-weighted MRI for MRI-guided Radiotherapy Joshua Nathan Freedman1,2, David John Collins2, Oliver Jacob Gurney-Champion1, Simeon Nill1, Uwe Oelfke1, Martin Osmund Leach2, and Andreas Wetscherek1 1Joint Department of Physics, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, United Kingdom, 2CR-UK Cancer Imaging Centre, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, United Kingdom

 119 13:45 Rapid MR Imaging of Ocular Movement using Shared K-Space Data for Radiotherapy Planning Luc van Vught1,2, Kirsten Koolstra2, and Jan-Willem Beenakker1,2 1Ophthalmology, Leiden University Medical Center, Leiden, Netherlands, 2Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, Netherlands

 120 13:45 Visual pathway structure and localisation of tumour-induced disturbance in optic pathway glioma: correlations between diffusion-MRI, visual evoked potentials, and optical coherence tomography Patrick W Hales1, Sian Handley2, Alki Liasis2, Darren Hargrave3, and Chris Clark1 1UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom, 2Opthalmology Department, Great Ormond Street Children’s Hospital, London, United Kingdom, 3Haematology and Oncology Department, Great Ormond Street Children’s Hospital, London, United Kingdom

 121 13:45 Differentiation between vasogenic edema and infiltrative tumor in patients with high grade gliomas using texture patch based analysis Moran Artzi1,2, Gilad Liberman1,3, Deborah T. Blumenthal2,4, Orna Aizenstein1, Felix Bokstein2,4, and Dafna Ben Bashat1,2,5 1Functional Brain Center, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel, 2Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel, 3Department of Chemical Physics, Weizmann Institute, Rehovot, Israel, 4Neuro-Oncology Service, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel, 5Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel

 122 13:45 Evaluating intratumoral necrosis in gliomas: a multi-modal study of acidosis, cellularity, and vascularity Maxime Parent1, John J. Walsh2, Lucas C. Adam1, Daniel Coman1, and D.S. Fahmeed Hyder1,2 1Radiology & Biomedical Imaging, Yale University, New Haven, CT, United States, 2Biomedical Engineering, Yale University, New Haven, CT, United States

 123 13:45 Oxygen enhanced-MRI detects radiotherapy-induced change in hypoxia in xenograft models and lung cancer patients Ahmed Salem1,2, Ross Little3, Adam Featherstone3, Muhammad Babur4, Hitesh Mistry4, Susan Cheung3, Yvonne Watson3, Victoria Tessyman4, Marie-Claude Asselin3, Alan Jackson3, Kaye Williams4, Geoffrey Parker3,5, Corinne Faivre-Finn1,2, and James O'Connor1,6 1Division of Cancer Sciences, University of Manchester, Manchester, United Kingdom, 2Department of Clinical Oncology, The Christie Hospital NHS Trust, Manchester, United Kingdom, 3Division of Informatics, Imaging and Data Sciences, University of Manchester, Manchester, United Kingdom, 4Division of Pharmacy and Optometry, University of Manchester, Manchester, United Kingdom, 5Bioxydyn Ltd, Manchester, United Kingdom, 6Department of Radiology, The Christie Hospital NHS Trust, Manchester, United Kingdom

 124 13:45 Assessment of Distant Tumor Stimulation from Liver Radiofrequency Ablation in a Rat Breast Carcinoma Model using Hyperpolarized 13C-Pyruvate MRI Joseph Scott Goodwin1, David Mwin1, Patricia Coutinho de Souza1, Svayam Dialani1, John T Moon1, Aaron K Grant1, Muneeb Ahmed1, and Leo L Tsai1 1Radiology, Beth Israel Deaconess Medical Center, Boston, MA, United States

 125 13:45 Late gadolinium enhancement of colorectal liver metastases post-chemotherapy is associated with tumour fibrosis and overall survival post-hepatectomy Helen Cheung1, Paul J Karanicolas2, Eugene Hsieh3, Natalie Coburn2, Tishan Maraj1, Jin J Kim1, Howaida Elhakim3, Masoom A Haider1, Calvin Law2, and Laurent Milot1 1Department of Medical Imaging, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada, 2Department of Surgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada, 3Department of Pathology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada

 126 13:45 Human Hyperpolarized 13C MR of Liver and Bone Metastases using both EPSI and EPI Acquisitions Zihan Zhu1,2, Jeremy W Gordon1, Hsin-Yu Chen1, Eugene Milshteyn1,2, Daniele Mammoli1, Lucas Carvajal1, Peter J Shin1, Rahul Aggarwal3, Robert Bok1, John Kurhanewicz1, Pamela Munster3, and Daniel B Vigneron1 1Department of Radiology and Biomedical Imaging, UCSF, San Francisco, CA, United States, 2UC Berkeley - UCSF Graduate Program in Bioengineering, UCSF, San Francisco, CA, United States, 3Department of Medicine, UCSF, San Francisco, CA, United States

 127 13:45 Two Dimensional COSY on Biopsy Distinguishes Indolent From Aggressive Kidney Masses Aaron Urquhart1, Sharon Del Vecchio2, Lutz Krause3, Robert Ellis2, Keng Lim Ng4, Hema Samaratunga5, Sonja Gustafson6, Graham Galloway1,3, Glenda Gobe2, Peter Malycha1, Simon Wood4, and Carolyn Mountford1 1Translational Research Institute, Brisbane, Australia, 2Faculty of Medicine, The University of Queensland, Brisbane, Australia, 3The University of Queensland, Brisbane, Australia, 4Department of Urology, Princess Alexandra Hospital, Brisbane, Australia, 5Aquesta Uropathology, Brisbane, Australia, 6Department of Radiology, Princess Alexandra Hospital, Brisbane, Australia

 128 13:45 In vivo cancer detection and dynamics with magnetic particle imaging Elaine Yu1, Mindy Bishop1, Bo Zheng1, R Matthew Ferguson2, Amit P Khandhar2, Scott J Kemp2, Kannan M Krishnan2,3, Patrick Goodwill1,4, and Steven Conolly1,5 1Department of Bioengineering, University of California, Berkeley, CA, United States, 2Lodespin Labs, Seattle, WA, United States, 3Department of Material Science and Engineering, University of Washington, Seattle, WA, United States, 4Magnetic Insight, Inc., Alameda, CA, United States, 5Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, CA, United States

 129 13:45 Ferumoxytol-enhanced MRI: Early Results in Solid Organ Masses. Puja Shahrouki1,2, Woo Kyoung Jeong1,3, Steven S. Raman1, Ely R. Felker1, David S. Lu1, and J. Paul Finn1,2 1Department of Radiological Sciences, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States, 2Diagnostic Cardiovascular Imaging Laboratory, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States, 3Department of Radiology and Imaging Sciences, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea

 130 13:45 Whole-Body MRI for Metastatic Cancer Detection using T2-Weighted Imaging with Fat and Fluid Suppression Xinzeng Wang1, Ali Pirasteh1, James Brugarolas2,3, Neil M. Rofsky1,4, Robert E. Lenkinski1,4, Ivan Pedrosa1,3,4, and Ananth J. Madhuranthakam1,4 1Radiology, UT Southwestern Medical Center, Dallas, TX, United States, 2Internal Medicine, UT Southwestern Medical Center, Dallas, TX, United States, 3Kidney Cancer Program, Simmons Comprehensive Cancer Center, UT Southwestern Medical Center, Dallas, TX, United States, 4Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX, United States

 131 13:45 Whole body functional and anatomical MRI: Accuracy in staging and interim response monitoring of Childhood and Adolescent Hodgkin’s Lymphoma compared to multimodality conventional imaging Arash Latifoltojar1, Shonit Punwani1, Andre Lopes2, Paul D Humphries1, Deena Neriman3, Leon Menezes3, Stephen Daw4, Ananth Shankar4, Bilyana Popova2, K M Mak2, Heather Fitzke1, Paul Smith2, Laura Clifton-Hadley2, and Stuart Andrew Taylor1 1Centre for Medical Imaging, University College London, London, United Kingdom, 2Cancer Research UK and UCL Cancer Trial Centre, University College London, London, United Kingdom, 3Institute of Nuclear Medicine, University College London Hospital, London, United Kingdom, 4Department of Paediatric Haemato-oncology, University College London Hospital, London, United Kingdom

Combined Educational & Scientific Session

### Applications of Microstructural Imaging in Disease

Organizers: Noam Shemesh, Fernando Calamante, Jennifer McNab

 N01 Monday 13:45 - 15:45 Moderators: Fernando Calamante & Noam Shemesh

 13:45 Microstructure/Diffusion-Mediated MRI Signals Jens H Jensen1 1Department of Neuroscience, Medical University of South Carolina, Charleston, SC, United States Diffusion MRI is highly sensitive to the microstructural properties of biological tissues, such as cellularity and membrane permeability. However, the connections between standard diffusion measures and specific microstructural properties are complex and subtle, making the biological interpretation of changes in diffusion measures associated with disease very challenging. Microstructural modeling has frequently been combined with diffusion MRI to improve interpretability, but the reliability of model predictions is often limited by uncertainties in their underlying assumptions. Here we review these considerations by examining several examples of how microstructure affects commonly employed diffusion measures.

 14:15 Application of Microstructure/Diffusion-Mediated Signals to Study Disease Matthew Budde1 1Medical College of Wisconsin, United States This talk will summarize state-of-the-art techniques to probe tissue microstructure and describe ongoing efforts to understand how the biology of nervous system tissue relates to DWI signal and models.

 132 14:45 Do Non-Gaussian diffusion MRI methods improve the detection or specification of cellular alterations following traumatic brain injury? Elizabeth B Hutchinson1,2, Sarah King1, Alexandru Avram3, M Okan Irfanoglu1, Michal Komlosh2,4, Susan Schwerin2,5, Eli Shindell5, Sharon Juliano5, and Carlo Pierpaoli1 1QMI/NIBIB, National Institutes of Health, Bethesda, MD, United States, 2Henry M. Jackson Foundation, Bethesda, MD, United States, 3NIBIB, National Institutes of Health, Bethesda, MD, United States, 4NICHD, National Institutes of Health, Bethesda, MD, United States, 5APG, Uniformed Services University, Bethesda, MD, United States Following traumatic brain injury (TBI), numerous microscale cellular alterations appear and evolve with a range of consequences for adverse outcomes and recovery.  Diffusion tensor MRI (DTI) has been identified as a potentially sensitive tool for characterizing these changes, but is notably limited in providing specific information about particular cellular alterations and more advanced non-Gaussian frameworks have been developed that may address these limitations.  To assess the utility of non-Gaussian modeling for improved detection and specification of TBI-related cellular alterations, we compared DTI, DKI and MAP-MRI in mouse brains following mild TBI and their correspondence to histopathology in the same tissue.

 133 14:57 Histological Validation of in-vivo VERDICT MRI for Prostate using 3D Personalised Moulds Elisenda Bonet-Carne1,2, Maira Tariq1, Hayley Pye3, Mrishta Brizmohun Appayya2, Aiman Haider4, Colleen Bayley1, Joseph Jacobs1, Alexander Freeman4, David Hawkes1, David Atkinson2, Greg Shaw5, Hayley Whitaker3, Daniel C Alexander1, Shonit Punwani2, and Eleftheria Panagiotaki1 1Centre for Medical Image Computing, University College London, London, United Kingdom, 2Centre for Medical Imaging, University College London, London, United Kingdom, 3Research Department for Tissue & Energy, University College London, London, United Kingdom, 4Department of Pathology, University College London Hospital, London, United Kingdom, 5Division of Surgery and Interventional Science, University College London, London, United Kingdom VERDICT analysis can successfully distinguish benign from malignant prostate tissue in-vivo showing promising results as a cancer diagnostic tool. However, the accuracy with which model parameters reflect the underlying tissue characteristics is unknown. In this study, we quantitatively compare the intracellular, extracellular-extravascular and vascular volume fractions derived from in-vivo VERDICT MRI against histological measurements from prostatectomies. We use 3D-printed personalised moulds designed from in-vivo MRI that help preserve the orientation and location of the gland and aid histological alignment. Results from the first samples using the 3D mould pipeline show good agreement between in-vivo VERDICT estimates and histology.

 134 15:09 Microscopic diffusion anisotropy reveals microstructural heterogeneity of malformations of cortical development associated with epilepsy: A b-tensor encoding study at 7T Björn Lampinen1, Ariadni Zampeli2, Filip Szczepankiewicz3,4, Maria Compagno Strandberg5, Kristina Källén6, Isabella M Björkman-Burtscher4, and Markus Nilsson4 1Clinical Sciences Lund, Medical Radiation Physics, Lund University, Lund, Sweden, 2Clinical Sciences Lund, Neurology, Lund University, Lund, Sweden, 3Random Walk Imaging AB, Lund, Sweden, 4Clinical Sciences Lund, Diagnostic Radiology, Lund University, Lund, Sweden, 5Skane University Hospital, Department of Clinical Sciences Lund, Neurology, Lund University, Lund, Sweden, 6Skane University Hospital, Department of Clinical Sciences Lund, AKVH-Neurology Helsingborg, Lund University, Lund, Sweden Malformations of cortical development are macro- or microscopic abnormalities of the cerebral cortex. Here, we investigated such malformations associated with epilepsy using b-tensor encoding, which is a recently developed technique that permits estimation of microscopic anisotropy also in regions where diffusion is isotropic on the voxel level. Results show a large heterogeneity in microscopic anisotropy between lesions, which we hypothesize represents different levels of axonal content. The characteristics of some types of lesions depended strongly on whether they were associated to other lesions, which could be clinically helpful for indicating hidden sources of epileptic seizures.

 135 15:21 Investigating microstructural heterogeneity of white matter hyperintensities in Alzheimer’s disease using single-shell 3-tissue constrained spherical deconvolution Remika Mito1,2, Thijs Dhollander1, David Raffelt1, Ying Xia3, Olivier Salvado3, Amy Brodtmann1,2, Christopher Rowe4,5, Victor Villemagne4,5, and Alan Connelly1,2 1Florey Institute of Neuroscience and Mental Health, Melbourne, Australia, 2Florey Department of Neuroscience and Mental Health, University of Melbourne, Melbourne, Australia, 3The Australian eHealth Research Centre, CSIRO Health and Biosecurity, Brisbane, Australia, 4Department of Medicine, Austin Health, University of Melbourne, Melbourne, Australia, 5Department of Molecular Imaging & Therapy, Centre for PET, Austin Health, University of Melbourne, Melbourne, Australia White matter hyperintensities (WMH) observed on FLAIR MRI are highly prevalent in Alzheimer’s disease. Although often associated with cognitive decline, such associations are highly variable, likely due to the underlying pathological heterogeneity within these lesions. Here, we explore this potential heterogeneity in vivo in an Alzheimer’s disease cohort, by investigating relative tissue fractions obtained using single-shell 3-tissue constrained spherical deconvolution (SS3T-CSD). We show distinguishable tissue profiles of lesions based on classification as periventricular or deep, and additionally show heterogeneity within lesions, thus highlighting the pitfalls of binary classification of WMH, and the value of investigating their underlying diffusional properties.

 136 15:33 Neurite Orientation Dispersion and Density Imaging: Added Value in the Detection of Tubers in Patients With Tuberous Sclerosis Complex Xiali Shao1, Xuewei Zhang2, Wenrui Xu1, Hua Guo3, Zhe Zhang3, Jieying Zhang3, Tao Jiang4, and Weihong Zhang1 1Department of radiology, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China, 2Department of interventional radiology, China Meitan General Hospital, Beijing, China, 3Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China, 4Department of Neurosurgery, China National Clinical Research Center for Neurological Diseases, Beijing, China The aim of this study was to evaluate the performance of Neurite Orientation Dispersion and Density Imaging (NODDI) in depicting cortical tubers in patients with tuberous sclerosis complex (TSC). By comparing with conventional MRI and DTI, the intracellular volume fraction (ICVF) derived from NODDI showed privilege over both techniques with higher sensitivity and better contrast ratio. Our result has revealed that NODDI was better at detecting microstructural disruption than DTI and conventional MRI sequences with a more reasonable model assumption, and may somehow shed light on the management of epilepsy in TSC patients.

 15:45 Adjournment & Meet the Teachers

Oral

### RF Arrays & Systems

 N03 Monday 13:45 - 15:45 Moderators: Nicola De Zanche & Manushka Vaidya

 137 13:45 The MRF Array: an iPRES Coil Array for Accelerated Magnetic Resonance Fingerprinting Michael Twieg1, Bhairav B. Mehta1, Shinya Handa2, Haoqin Zhu2, Michael Wyban2, Steven Tokar2, Labros Petropoulos2, Hiroyuki Fujita2, Sherry Huang3, Andrew Dupuis3, and Mark A Griswold1,3 1Department of Radiology, Case Western Reserve University, Cleveland, OH, United States, 2Quality Electrodynamics, Mayfield Heights, OH, United States, 3Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States Magnetic Resonance Fingerprinting (MRF) depends on spatially and temporally incoherent encoding fields for fast quantitative imaging. However the achievable encoding is limited by hardware. The iPRES concept, which adds ΔB0 and B1+ encoding to a receive array, is an excellent candidate for additional encoding for MRF. Here we present preliminary results of a 16 channel iPRES array, referred to as the MRF array. The MRF array uses in-bore power amplifiers to provide vastly increased encoding capabilities while minimizing the cost of additional hardware. Such encoding schemes are expected to allow for acceleration of quantitative imaging techniques such as MRF.

 138 13:57 Optimization and validation of dipole antenna geometry for body imaging at 10.5T Bart R. Steensma1, Pierre-Francois van de Moortele2, Arcan M. Erturk2, Andrea Grant2, Gregor Adriany2, Gregory J. Metzger2, and Alexander J.E. Raaijmakers1,3 1Radiology, University Medical Center Utrecht, Utrecht, Netherlands, 2Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States, 3Biomedical Image Analysis, Eindhoven University of Technology, Eindhoven, Netherlands Body MRI at 10.5T shows potential for improving signal-to-noise ratio compared to 7T, but is limited by increased specific absorption rate (SAR) levels. In this work, the geometry of a dipole antenna is optimized for body imaging with low SAR levels at 10.5T. The optimized dipole geometry is compared to a previous design in simulations on a human model, where it is shown that SAR levels can be decreased by 36% for an equal transmit efficiency. Simulations are validated by magnetic resonance thermometry and B1+-mapping experiments with a 12-channel multi-transmit array.

 139 14:09 Ultimate intrinsic transmit efficiency for RF shimming Ioannis P. Georgakis1, Athanasios G. Polimeridis1, and Riccardo Lattanzi2,3,4 1Center for Computational and Data-Intensive Science and Engineering (CDISE), Skolkovo Institute of Science and Technology, Moscow, Russian Federation, 2Center for Advanced Imaging Innovation and Research (CAI2R), Department of Radiology, New York University School of Medicine, New York, NY, United States, 3Bernard and Irene Schwartz Center for Biomedical Imaging (CBI), Department of Radiology, New York University School of Medicine, New York, NY, United States, 4Sackler Institute of Graduate Biomedical Sciences, New York University School of Medicine, New York, NY, United States We introduce a new performance metric for RF shimming, the ultimate intrinsic transmit efficiency (UITXE), which provides an absolute reference independent of any particular coil design. We show in simulation that it represents a performance upper bound, which could be approached with finite transmit arrays with an increasing number of coils. In particular, we demonstrated that a 24-channel array could achieve 70% of the UITXE. UITXE could be employed in a straightforward manner in experiments to assess absolute performance of actual arrays and evaluate RF shimming approaches. The associated ideal current patterns could provide new insight for optimal array design.

 140 14:21 32-Channel Combined Surface Loop / “Vertical” Loop Tight-Fit Array Provides for Full-Brain Coverage, High Transmit Performance, and SNR Improvement at 9.4T: an Alternative to Surface Loop / Dipole Antenna Combination. Nikolai Avdievich1,2, Ioannis Angelos Giapitzakis2, and Anke Henning1,2 1Institute of Physics, Ernst-Moritz-Arndt University Greifswald, Greifswald, Germany, 2High-Field MR Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany Tight-fit human head ultra-high field (UHF,>7T) transceiver (TxRx) surface loop phased arrays improve transmit (Tx)-efficiency in comparison to Tx-only arrays, which are larger to fit receive (Rx)-only arrays inside. A drawback of the TxRx-design is that the number of array elements is restricted by the number of available RF Tx-channels (commonly <16), which limits the Rx-performance. A new 32-element tight-fit human head array, which consists of 18 TxRx-loops and 14 Rx-only vertical loops, was constructed. The array provides for full-brain coverage, ~50% greater B1+, and ~30% greater SNR near the brain center as compared to common Tx-only/ Rx-only (ToRo) array.

 141 14:33 Evaluation of Parallel Imaging performance gains with 64 channel receivers at 7 Tesla Steen Moeller1, Andrea Grant1, Xiaoping Wu1, Lance Delabarre1, Pierre-Francois Van de Moortele1, Jerahmie Radder1, Scott Schillack2, Edward Auerbach1, Gregor Adriany1, and Kamil Ugurbil1 1Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States, 2Lifeservices LLC, Minneapolis, MN, United States Evaluation of a 64 channel receiver relative to a 32 channel receiver shows that gains in parallel imaging performance for SMS/MB of 40 to 60% is feasible, such that, highly desirable, single-shot, multislice, whole brain coverage with <1s TR and 1mm or better isotropic resolutions would be achievable at 7T.

 142 14:45 Feasibility Study of a Double Resonant (23Na/1H) 8 Channel Rx Head Coil for MRI at 3T Matthias Malzacher1, Mathias Davids1, Jorge Chacon-Caldera1, and Lothar R. Schad1 1Computer Assisted Clinical Medicine,Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany The implementation of 23Na-sodium MRI in the clinical routine is of increasing interest since it can provide valuable information on tissue viability. A design criterion of such double resonant RF setups is to keep the performance of the 1H MRI approximately at the same level as single resonant setups while optimizing the 23Na imaging. This work investigates the feasibility and performance of a double resonant 8 channel receive (Rx) head coil for 1H and 23Na MRI at 3T using EM simulations and a head model.

 143 14:57 Whole-body 7T 31P birdcage transmit coil driven by a 35kW RF amplifier with an integrated 30-element 31P receive array and an 8-element 1H transmit/receive array Ladislav Valkovic1,2, Alex Batzakis3, Jane Ellis1, Lucian Purvis1, Albrecht I Schmid1,4, Matthew D Robson1, Dennis WJ Klomp3,5, and Christopher T Rodgers1,6 1Oxford Centre for Clinical MR Research (OCMR), RDM Cardiovascular Medicine, University of Oxford, Oxford, United Kingdom, 2Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sceinces, Bratislava, Slovakia, 3MR Coils BV, Zaltbommel, Netherlands, 4High-Field MR Centre, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria, 5Department of Radiology, University Medical Center Utrecht, Utrecht, Netherlands, 6The Wolfson Brain Imaging Centre, University of Cambridge, Cambridge, United Kingdom We describe our experiences implementing a whole-body transmit coil driven by a 35kW RF power amplifier, with a 30-element 31P receive array, and an 8-element 1H transmit/receive array, optimised for cardiac 31P-MRS at 7T. We describe an adaptation to the vendor’s standard SAR monitoring to monitor RF power levels up to the full 35kW output of the RFPA. This new hardware was found to achieve better 31P B1+ and SNR at the depth of the heart than other coils available in our institution. This setup promises to allow the first regionally-resolved, whole-heart 31P-MRSI studies at 7T in the near future.

 144 15:09 A 16-channel Rx-only radiofrequency coil for MR spine imaging at 7T Stefan HG Rietsch1,2, Stephan Orzada1, Jonathan Weine1, Leonard Ruschen1, Sarah Handtke1,3, Raphaela M Berghs1,3, Jessica Kohl1,4, Sascha Brunheim1,2, Mark E Ladd5, and Harald H Quick1,2 1Erwin L. Hahn Institute for Magnetic Resonance Imaging, University of Duisburg-Essen, Essen, Germany, 2High-Field and Hybrid MR Imaging, University Hospital Essen, Essen, Germany, 3Hamm-Lippstadt University of Applied Sciences, Hamm, Germany, 4University of Applied Science Ruhr West, Mülheim an der Ruhr, Germany, 5Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany In clinical MRI systems operating at 1.5 and 3T, built-in 1-channel radiofrequency (RF) transmit body coils are broadly used in conjunction with local receive RF coils. Recently, a 32-channel Tx/Rx remote body coil has been presented for 7T body MRI. In this work we present an additional 16-channel receive-only spine coil to boost signal-to-noise ratio in comparison to measurements where only the 32-channel Tx/Rx remote body coil is used for reception. The SNR gain is demonstrated in a body-sized phantom. Furthermore, first in-vivo imaging results for 7T MRI of the spine during free-breathing are shown.

 145 15:21 Higher and more homogeneous B$_1^+$ for bilateral breast imaging at 7T using a multi-transmit setup with 5 dipole antennas and a 30-loop element receive array Erwin Krikken1, Bart R. Steensma1, Ingmar J. Voogt1, Erik R. Huijing1, Dennis W.J. Klomp1, Jannie P. Wijnen1, and Alexander J.E. Raaijmakers1,2 1Radiology, UMC Utrecht, Utrecht, Netherlands, 2Biomedical Image Analysis, Eindhoven University of Technology, Eindhoven, Netherlands Imaging of the breast at 7 tesla is compromised by the inhomogeneous B1+. To overcome this challenge we explored the use of five fractionated dipole antennas in a multi-transmit system in combination with 30 receiver coils. This coil shows larger SNR, larger FOV and higher and more homogeneous B1 field in the breasts than the currently used breast coil at our institute. The high B1+ and an increased field of view achieved by the fractionated dipole antennas, opens the way to translate routinely used breast imaging protocols from 3T to 7T enabling advanced clinical research.

 146 15:33 31-channel receive coil array combined with an 8-channel whole-brain dipole transmit array Jérémie Clément1, Rolf Gruetter1,2,3, and Özlem Ipek4 1LIFMET, EPFL, Lausanne, Switzerland, 2Department of Radiology, University of Lausanne, Lausanne, Switzerland, 3Department of Radiology, University of Geneva, Geneva, Switzerland, 4CIBM-AIT, EPFL, Lausanne, Switzerland To increase the parallel imaging performances while keeping high transmit field, the combination of a high-density receive coil array and a tight-fitted whole-brain dipole coil array was investigated. Measured noise correlation matrix, signal-to-noise ratio and g-factor maps were evaluated for the 31-channel receive coil array, and MRI acquisition time could be decreased up to 3.4 times without attenuation in data quality. MR images demonstrated a large spatial coverage, including cerebellum and cerebral cortex, thanks to the whole-brain dipole transmit array while the 31-channel receive coil array provided highly accelerated image acquisition.

Oral

### fMRI: Spatiotemporal Dynamics

 N04 Monday 13:45 - 15:45 Moderators: Catie Chang & Laurentius Huber

 147 13:45 Imaging Primary Neuronal Activity in the Human Optical Cortex at 1.35Hz Jose de Arcos1, Daniel Fovargue 1, Katharina Schregel2,3, Radhouene Neji1,4, Samuel Patz2, and Ralph Sinkus1 1Department of Biomedical Engineering, King's College London, London, United Kingdom, 2Brigham and Women's Hospital, Boston, MA, United States, 3Institute of Neuroradiology, University Medical Center Goettingen, Goettingen, Germany, 4MR Research Collaborations, Siemens Healthcare Limited, Frimley, United Kingdom In this work we have developed a novel functional MRE system for humans capable of probing stiffness changes in the brain driven by monocular visual stimulation. A continuous visual stimulus was applied at an ON/OFF frequency of 1.35 Hz during a segmented 2D multi-slice MRE sequence with 3D motion encoding operating at 50 Hz vibration frequency. Significant stiffness changes were recorded between ON/OFF during the stimulus experiment that also differed in baseline to control scans (OFF/OFF). Since the BOLD signal is entirely saturated at such high stimulation frequencies, we hypothesize that stiffness changes are due to direct neuronal activities. Data match similar results obtained in mice.

 148 13:57 Inter-Regional BOLD Latency after Vascular Reactivity Calibration is Correlated to Reaction Time Yi-Tien Li1,2, Pu-Yeh Wu1, Jacky Tai-Yu Lu3, Ying-Hua Chu1, Yi-Cheng Hsu1, and Fa-Hsuan Lin1,4 1Institute of Biomedical Imaging, National Taiwan University, Taipei, Taiwan, 2Department of Medical Imaging, Taipei Medical University-Shuang Ho Hospital, New Taipei, Taiwan, 3Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan, 4Department of Neuroscience and Biomedical Engineering, Aalto University, Espoo, Finland Inter-regional BOLD latency between visual and sensimotor cortices were first monitored with fast fMRI (TR=0.1 s) and then calibrated for vascular reactivity using a breath-holding task. Significant delayed response (left: t=4.0, p=0.0019; right: t=6.0, p<0.0001) in the sensorimotor cortex was observed than the visual cortex was detected after removing the vascular confound. Significant correlation between reaction time (428 ± 41ms) and the inter-regional BOLD timing difference (432 ± 149ms) was found within and across subjects.

 149 14:09 Global responses to microstimulation at 7T and comparison with vibrotactile stimulation Ayan Sengupta1, Rochelle Ackerley2, Roger Watkins2, Rosa Sanchez Panchuelo1, Paul Glover1, Johan Wessberg2, and Susan Francis1 1Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, United Kingdom, 2Department of Physiology, University of Gothenburg, Gothenburg, Sweden Single unit intra-neural microstimulation (INMS) allows the precise delivery of low-current electrical pulses into human peripheral nerves to stimulate individual afferent nerve fibres. We compare the global pattern of positive and negative BOLD response to INMS with that of perceptually matched vibrotactile stimulation of the skin. INMS and vibrotactile stimulation result in a similar pattern of positive BOLD response, but distinct differences in negative BOLD signals. INMS results in strong negative BOLD response of the DMN, whilst vibrotactile stimulation results in strong ipsilateral negative BOLD response likely to represent active inhibition which is not seen for INMS.

 150 14:21 Ultrahigh spatiotemporal-resolution fMRI reveals distinct brain-wide functional networks of different hippocampal subfields Wei-Tang Chang1, Kelly Sullivan Giovanello2, and Weili Lin1 1BRIC, UNC at Chapel Hill, Chapel Hill, NC, United States, 2Department of Psychology, UNC at Chapel Hill, Chapel Hill, NC, United States The hippocampal formation consists of distinct subfields, which contribute to different aspects of memory function, and exhibit different brain network topologies. However, the brain-wide resting-state functional connectivity of hippocampal subfields in human remains poorly understood mainly due to technical limitations. Previous efforts to identify hippocampal subfield functional networks compromised either spatial resolution, spatial coverage or temporal resolution. We have developed a new approach, named Partition-encoded Simultaneous Multi-slab (PRISM), capable of acquiring ultrahigh isotropic resolution images while maintaining the acceleration capability. Our results of resting-state functional connectivity at 7T reveal distinct brain-wide functional networks associated with different hippocampal subfields.

 151 14:33 High-frequency BOLD responses in human thalamus detected through fast fMRI at 7 Tesla Laura D Lewis1,2, Kawin Setsompop1,3, Bruce Rosen1,4, and Jonathan R Polimeni1,4 1Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, United States, 2Society of Fellows, Harvard University, Cambridge, MA, United States, 3Radiology, Harvard Medical School, boston, MA, United States, 4Radiology, Harvard Medical School, Boston, MA, United States No current technique can noninvasively localize neural activity in human subcortical structures at subsecond temporal resolution. Recent studies have demonstrated that fast (>0.2 Hz) fMRI responses can be detected in human cortex. We aimed to test whether fast fMRI signals can also be detected in the thalamus. We presented oscillating visual stimuli in order to induce oscillatory neural activity in visual thalamus, and observed large-amplitude fMRI oscillations at 0.5 Hz. We conclude that high-frequency fMRI responses can be detected in thalamus, suggesting fast fMRI has the potential to be used for whole-brain imaging.

 152 14:45 Functional organization of visual temporal frequency preference revealed by thalamo-visual correlation Yuhui Chai1, Daniel Handwerker1, Sean Marrett1, Andrew Hall1, Javier Gonzalez-Castillo1, Peter Molfese1, and Peter Bandettini1 1National Institute of Mental Health, National Institutes of Health, Bethesda, MD, United States Thalamo-visual connections play an important role in the visual system. Little is known about the temporal frequency tuning properties of the thalamo-visual correlation in humans. Here we demonstrated that thalamo-visual correlation is significantly modulated by the temporal frequency of a stimulus. Using correlation with thalamus as an index, human visual cortex is organized along a temporal dimension, with the anterior calcarine preferring low temporal frequencies and posterior calcarine preferring higher temporal frequencies.

 153 14:57 Probing temporal information in fast-TR fMRI data during attention modulations Luca Vizioli1 and Essa Yacoub1 1CMRR, University of Minnesota, Minneapolis, MN, United States The introduction of fast-TRs has allowed for explorations of temporal features in fMRI data. Further, the ability to concurrently retain relatively high degrees of spatial precision as well as large volume coverage, while also maintaining high SNR efficiency, could provide unprecedented axis to the human brain. In this work we explore the possibility of exploiting the temporal specificity of fMRI using a temporal multi-voxel pattern analysis and high temporal resolution 7T fMRI data during attention modulations.

 154 15:09 Mesoscopic and microscopic imaging of sensory responses in the same animal Davide Boido1, Ravi L Rungta1, Bruno-Felix Osmanski2, Morgane Roche1, Tomokazu Tsurugizawa3, Denis LeBihan3, Luisa Ciobanu3, and Serge Charpak1 1INSERM U1128, Laboratory of Neurophysiology and New Microscopy, Université Paris Descartes, Paris, France, 2INSERM U979 ‘Wave Physics for Medicine’ Lab, Paris, France, 3NeuroSpin, Bât 145, Commissariat à l'Energie Atomique-Saclay Center, Gif-sur-Yvette, France We developed a chronic olfactory bulb preparation compatible with repetitive imaging of the same mice with BOLD-fMRI (17.2 T), functional ultrasound imaging (fUS) and two-photon laser scanning microscopy. BOLD-fMRI and fUS mesoscopic signals are highly correlated with microscopic vascular and dendritic neuronal signals in response to odour concentrations. Furthermore, minimal odour stimulation reveals that there is no threshold of neuronal activation below which functional hyperemia is not triggered, warranting measurement of blood flow dynamics to detect the lowest levels of brain activation. These data establish the strengths and limits of mesoscopic imaging techniques to report neural activity.

 155 15:21 A transfer function model for local signal propagation in spatiotemporal MR data Henning U. Voss1, Jörg Stadler2, Jonathan P. Dyke1, and Douglas J. Ballon1 1Weill Cornell Medicine, New York, NY, United States, 2Leibniz Institute for Neurobiology, Magdeburg, Germany In order to understand the sources of dynamic EPI signals under complex stimuli or in the resting state, local signal transfer functions were computed from natural stimulation data sets, and the coherence vector was mapped and color coded analogously to conventional methods for structural connectivity maps. As expected, signal propagation is frequency dependent, whereas high frequencies are caused by cardiovascular pulsations, but low frequencies are less well understood. We conclude that the observed frequency dependence of this local signal transfer model might aid the understanding of the foundation of functional connectivity analysis and the meaning of observed complex patterns such as the resting states.

 156 15:33 Visceral stimulation triggers high-frequency BOLD responses in the rat brain Jiayue Cherry Cao1, Kun-Han Lu2, Robert Phillips3, Terry L. Powley1,3, and Zhongming Liu1,2 1Biomedical Engineering, Purdue University, West Lafayette, IN, United States, 2Electrical and Computer Engineering, Purdue University, West Lafayette, IN, United States, 3Psychological Science, Purdue University, West Lafayette, IN, United States Blood oxygen level dependent (BOLD) fMRI reports brain activity by measuring the vascular response to neural activity mediated through neurovascular coupling. Theoretical modeling of neurovascular coupling suggests its effect as a low-pass filter that cuts off at <0.2Hz. However, recent evidence suggests that BOLD fluctuations may also contain high frequency components. From a different perspective to address the origin of high-frequency BOLD signals in the rat brain, we examined the BOLD and local field potential (LFP) responses to visceral stimulation (electrical stimulation of the stomach or the vagus nerve), in comparison with the corresponding responses to commonly used sensory stimulation, such as forepaw stimulation. We report herein that visceral (forestomach and vagal nerve) stimulation can induce high-frequency (up to 0.8Hz) BOLD responses. The neuronal origins of such responses are different from those underlying the responses to forepaw stimulation, and likely modulate hemodynamic fluctuations through a more rapid mechanism of vascular control.

Oral

### MRS/MRSI Reconstruction & Quantification

 S02 Monday 13:45 - 15:45 Moderators: Cristina Cudalbu & Nuno Miguel Pedrosa de Barros

 157 13:45 Automatic Removal of Ghosting Artifacts from MR Spectra using Deep Learning Sreenath Pruthviraj Kyathanahally1, André Döring1, and Roland Kreis1 1Depts. Radiology and Biomedical Research, University of Bern, Bern, Switzerland Ghosting artifacts in clinical MR spectroscopy are problematic since they superimpose with metabolites and lead to inaccurate quantification. Here, we make use of “Deep Learning” (DL) methods to remove ghosting artifacts in MR spectra of human brain. The DL method was trained on a huge database of simulated spectra with and without ghosting artifacts, which represent complex variants of ghost-ridden spectra, transformed to time-frequency spectrograms. The trained model was tested on simulated and in-vivo spectra. The preliminary results for ghost removal show potential in simulated and in-vivo spectra, but need further refinement and quantitative testing.

 158 13:57 A novel structured low-rank framework for ghost removal and denoising of EPSI data Ipshita Bhattacharya1, Ralph Noeske 2, Rolf F Schulte3, and Mathews Jacob1 1Electrical and Computer Engineering, The University of Iowa, Iowa City, IA, United States, 2GE Healthcare, Postdam, Germany, 3GE Global Research, Munich, Germany Spectral interleaving is often used in echoplanar spectroscopic imaging (EPSI) sequences to achieve high spatial and spectral resolution, especially on high field scanners with larger chemical shift dispersion. Unfortunately, a major roadblock is the spurious Nyquist ghost artifacts, resulting from phase errors between interleaves. We introduce a novel framework, that simultaneously capitalizes on annihilation relation between the interleaves introduced by phase relations, as well as a linear predicability of the spectra, to remove the phase errors and to provide spectral denoising of the spectra. In addition, we also exploit on the low-rank structure of the EPSI data to provide additional spatial denoising, which will further improve the signal to noise ratio of the datasets.

 159 14:09 To which extent the Cramér-Rao bound (CRB) is a reliable benchmark in quantitative MRS? Guilhem Pagès1 and Jean-Marie Bonny1 1AgroResonance - UR370 QuaPA, INRA, Saint Genès Champanelle, France Following MRS data fitting, absolute or relative Cramér-Rao bounds (CRB and rCRB, respectively) are often computed as indices of parameter uncertainties. However, the unknown true values of parameters are required to compute CRB. Here, we studied the effect of substituting the true values by the noisy estimates on the bounds (noted CRB* and rCRB*). We showed by simulations that both CRB* and rCRB* are particularly sensitive to noise. Also, the mode of rCRB* distribution is left-shifted, which leads to a significant false positive risk when rCRB* is thresholded. A threshold not exceeding 20% is recommended to limit this risk.

 161 14:33 Towards in vivo neurochemical profiling of multiple sclerosis with MR spectroscopy at 7 Tesla: Apparent increase in frontal cortex water T2 in aged patients with progressive multiple sclerosis stabilizes in biexponential model constrained by tissue and CSF partial volumes Kelley M. Swanberg1,2, Hetty Prinsen1, Abhinav V. Kurada2, Katherine DeStefano3, Mary Bailey4, David Pitt3, Robert K. Fulbright1, and Christoph Juchem1,2,3,5 1Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, United States, 2Department of Biomedical Engineering, Columbia University School of Engineering and Applied Science, New York, NY, United States, 3Department of Neurology, Yale University School of Medicine, New Haven, CT, United States, 4Mandell Multiple Sclerosis Center, Saint Francis Hospital, Hartford, CT, United States, 5Department of Radiology, Columbia University Medical Center, New York, NY, United States Water is a common internal reference for metabolite quantification by 1H-MRS. We investigate potential influences on water-referenced metabolite quantification by differences in frontal cortex water T2 in individuals with relapsing-remitting, progressive, and no multiple sclerosis. Water T2 differed in monoexponential models, exhibiting highest values in progressive multiple sclerosis only when analyses were not age-controlled. Groupwise T2 did not differ in biexponential models constrained by tissue and CSF partial volumes, suggesting that monoexponential T2 differences reflected disparate proportions of water in tissue and CSF rather than differential behavior within them. Our results suggest stability of water T2 within frontal cortex tissue and CSF with multiple sclerosis and emphasize the superiority of metabolite quantification with group-specific T2 values when voxel composition may differ.

 162 14:45 Metabolite Quantification of 1H-MRSI spectra in Multiple Sclerosis: A Machine Learning Approach Dhritiman Das1,2,3, Mike E Davies2, Jeremy Chataway4, Siddharthan Chandran3, Bjoern H Menze1, and Ian Marshall3 1Department of Computer Science, Technical University of Munich, Munich, Germany, 2Institute for Digital Communications, University of Edinburgh, Edinburgh, Scotland, 3Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, Scotland, 4Queen Square Multiple Sclerosis Centre, Department of Neuroinflammation, University College London, London, United Kingdom As an alternative to model-based spectral fitting tools, we introduce a machine-learning framework for estimating metabolite concentrations in MR spectra acquired from a homogeneous cohort of 42 patients with Secondary Progressive Multiple Sclerosis. Our framework based on random-forest regression performs a 42-fold cross validation on this dataset which involves (1) learning the spectral features from this cohort; (2) estimating concentrations and calculating relative error over the LCModel estimates. Compared to the LCModel, our method, after training, gives a low estimation error and a 60-fold improvement in estimation speed per patient.

 163 14:57 Quantification of Phosphatidylcholine in the gall bladder using 31P MRSI suggest differences in biliary disorders: A Pilot Study. Lorenz Pfleger1,2, Emina Halilbasic3, Martin Gajdošík1,4, Marek Chmelík2,5,6, Sigfried Trattnig2,7, Michael Trauner3, and Martin Krššák1,2 1Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria, 2High-field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria, 3Division of Gastroenterology and Hepatology, Department of Medicine III, Medical University of Vienna, Vienna, Austria, 4Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, United States, 5Faculty of Healthcare, University of Prešov, Prešov, Slovakia, 6Department of Radiology, General Hospital of Levoča, Levoča, Slovakia, 7Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna, Austria This study focuses on quantification of phosphatidylcholine (PtdC) in the gall bladder and investigates concentration differences between biliary pathologies and healthy subjects. Significant different PtdC content was detected in patients suffering from primary sclerosing cholangitis (PSC). Subjects with primary biliary cholangitis (PBC) showed high variances in PtdC concentration. Even though, the PSC and control group are relatively small our results justify for further ongoing studies on this topic.

 164 15:09 Neural-network discrimination of cardiac disease from 31P MRS measures of myocardial creatine kinase energy metabolism Meiyappan Solaiyappan1, Robert G. Weiss2, and Paul A. Bottomley3 1Radiology, Division of MR Research, Johns Hopkins University, Baltimore, MD, United States, 2Medicine, Division of Cardiology, Johns Hopkins University, Baltimore, MD, United States, 3Radiology, Division of MR Resaerch, Johns Hopkins University, Baltimore, MD, United States Myocardial energy demands are the highest in the body and cardiac metabolism is altered in common diseases. Only phosphorus magnetic resonance spectroscopy (MRS) can measure ATP and creatine-kinase (CK) metabolism, a primary reserve of ATP, noninvasively in the human heart. Here, neural-network analysis is used to test whether the combination of 31P MRS measurements of phosphocreatine and [ATP] concentrations, the CK reaction-rate and its ATP flux, can discriminate cardiac diseases among prior study data from 178 subjects. We find that a three-layer neural-network adequately discriminates diseases without over-training, suggesting that heretofore unidentified differences in CK metabolism may underlie cardiac disease.

 165 15:21 Enhancing In Vivo Hyperpolarized 13C Chemical Shift Imaging by an Iterative Reconstruction Gil Farkash1, Stefan Markovic 1, and Lucio Frydman1 1Chemical & Biological Physics, Weizmann Institue, Rehovot, Israel Hyperpolarized 13C magnetic resonance spectroscopic imaging (MRSI) is a powerful metabolic technique, but it’s challenged by a rapid and irreversible decay of the signal that usually compromises its achievable spatial resolution. In this work we explore a way to improve this by utilizing a priori anatomical information derived from 1H MRI. Enhanced HP-MRSI implementations based on Spectroscopy with Linear Algebraic Modeling (SLAM) were thus assayed, to enhance HP-MRSI’s spatial resolution without compromising SNR. 13C experiments were performed in-vivo and pyruvate/lactate images reconstructed for physiological compartments by SLAM; we compare these results to those arising by traditional Fourier analyses.

 166 15:33 Constrained MRSI Reconstruction Using Water Side Information with a Kernel-Based Method Yudu Li1,2, Fan Lam2, Bryan Clifford1,2, Rong Guo1,2, Xi Peng2,3, and Zhi-Pei Liang1,2 1Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, United States, 2Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States, 3Paul C. Lauterbur Research Center for Biomedical Imaging, Institutes of Advanced Technology, Shenzhen, China Reconstruction for MR spectroscopic imaging (MRSI) is a challenging problem where incorporation of spatiospectral prior information is often necessary. While spectral constraints have been effectively utilized in the form of temporal basis functions, spatial constraints are often imposed using spatial regularization. In this work, we present a new kernel-based method to incorporate a priori spatial information, which was motivated by the success of kernel-based methods in machine learning. It provides a new mechanism for constrained image reconstruction, effectively incorporating a priori spatial information. The proposed method has been evaluated using both simulation and in vivo data, producing very impressive results. This new reconstruction scheme can be used to process any MRSI data, especially those from high-resolution MRSI experiments.

Oral

### Measuring & Correcting Imperfections

 S03 Monday 13:45 - 15:45 Moderators: Nicolas Boulant & S. Johanna Vannesjo

 167 13:45 On pseudo-concomitant fields caused by gradient coil vibrations Yi-Cheng Hsu1,2, Ying-Hua Chu1,2, Fa-Hsuan Lin2, and Maxim Zaitsev1 1Dept. of Radiology, Medical Physics, Medical Center University of Freiburg, Faculty of Medicine, Freiburg, Germany, 2Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan We demonstrate that a negative quadratic phase accrual, which we term a pseudo-concomitant field, is likely to be caused by gradient vibration and has a nearly constant spatial distribution. Accounting for this effect may be of importance for phase-sensitive MR applications utilizing strong gradients, such as flow imaging.

 168 13:57 $B_{0}$-component determination of the gradient system transfer function using standard MR scanner hardware Manuel Stich1,2, Tobias Wech1, Anne Slawig1,2, Gudrun Ruyters3, Andrew Dewdney3, Ralf Ringler2, Thorsten A. Bley1, and Herbert Köstler1 1Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Würzburg, Germany, 2X-Ray and Molecular Imaging Laboratory, Ostbayerische Technische Hochschule Amberg-Weiden, Weiden, Germany, 3Siemens Healthcare GmbH, Erlangen, Germany As a linear and time-invariant (LTI) system, the dynamic gradient system can be described by the system transfer function. While special measurement equipment like field cameras can be used to precisely determine even higher orders of the transfer function, phantom-based approaches were introduced for alternative determination without additional hardware needed. This study reports on phantom-based measurements of B0-components, which resulted in transfer functions with sufficiently high resolution for the characterization of mechanical resonances.

 169 14:09 GIRF measurement using a combination of triangular and chirp waveform input functions Peter Mazurkewitz1, Jürgen Rahmer1, and Peter Börnert1 1Philips Research Europe, Hamburg, Germany Gradient-impulse-response-function (GIRF) measurement is a well-established method for MRI gradient-system characterization. Typical GIRF input-functions are triangles or chirps. For triangles, measurements have to be performed with different pulse lengths to get a continuous frequency spectrum due to blind spots in the spectrum, requiring long scan times. In contrast, the spectrum of the chirp waveform covers a large frequency range without blind spots. However, at low frequencies the chirp fails due to a diverging intensity in its spectrum. We interleaved both waveforms and obtained a continuous gradient modulation transfer function (GMTF) spectrum down to low frequencies in short measurement time.

 170 14:21 Spatially-selective excitation using a tailored nonlinear ΔB0 pattern generated by an integrated multi-coil ΔB0/Rx array Jason Stockmann1,2, Nicolas S Arango3, Benedikt Poser4, Thomas Witzel1,2, Jacob White3, Lawrence L Wald1,2,5, and Jonathan R Polimeni1,2,5 1Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 2Harvard Medical School, Boston, MA, United States, 3Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States, 4Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands, 5Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, United States Multi-coil ΔB0 shim arrays have recently been used for zoomed imaging of target ROIs in mice, providing improved acquisition efficiency without the high SAR, long RF pulses, and other limitations of conventional selective excitation methods that rely solely on linear gradients.  We extend this work to zoomed 3D EPI in humans using an integrated ΔB0/Rx array coil to dynamically switch-on a static, spatially-tailored nonlinear ΔB0 pattern during RF excitation.  Proof-of-concept selective excitations of the occipital visual cortex and the peripheral cerebrum are shown, with strong correspondence to the target patterns.  Four-fold in-plane undersampled EPI of occipital visual cortex demonstrates the method’s potential for efficient high-resolution neuroimaging.

 171 14:33 Improved multi-band RF performance using GRATER-based predistortion Vanessa Landes1 and Krishna Nayak2 1Biomedical Engineering, University of Southern California, Los Angeles, CA, United States, 2Electrical Engineering, University of Southern California, Los Angeles, CA, United States The Gradient Reversal Approach to Evaluate RF (GRATER) has been shown to accurately measure small-tip RF pulses in phantoms, without the need for added hardware or sophisticated processing. Imperfect RF production can be measured with GRATER, and RF waveforms can be appropriately predistorted. We demonstrate substantial improvements in multi-band RF performance using this approach.  For example, a 0.648 ms, 30º FA, 4- band RF pulse with 2 cm center-to-center spacing and 5 mm slice thickness (desirable for SMS cardiac imaging) excites spurious side-lobes with 10.4% and 3.4% max signal before and after GRATER-based RF predistortion, respectively.

 172 14:45 MR Fingerprinting (MRF) incorporating simultaneous detection of RF transmit field and B0 inhomogeneity Huihui Ye1,2, Qing Li2, Xiaozhi Cao2, Qiuping Ding2, Hongjian He2, Huafeng Liu1, and Jianghui Zhong2 1State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, China, 2Center for Brain Imaging Science and Technology, Department of Biomedical Engineering, Zhejiang University, Hangzhou, China MR fingerprinting with B1+ and B0 field inhomogeneity detection is proposed with an IR-spoiled GRE based sequence. With this sequence, a 12s/slice acquisition simultaneously provide unbiased T1, T2* maps and B1+, B0 information at isotropic 1mm resolution.

 173 14:57 Deep Learning Based Approach for Main and RF Field Maps Estimation in MRI Kavitha Manickam1 and Jaganathan Vellagoundar1 1GE Healthcare, Bangalore, India In MRI, automatic estimation of main (B0) and RF (B1) field maps from the scanned images will help daily quality assurance and field corrected reconstruction.  In this paper, a novel approach based on deep learning technique is presented to estimate B0 and B1 maps from the scanned images.  A modified version of stacked convolutional encoder with random skip connections deep learning network is constructed.  Two separate networks  are used to estimate B0 and B1 maps individually. The networks are trained and tested with phantom images. The results show that the estimated maps are comparable to the actual field maps. Automatic map estimation based on deep learning approach is the first step towards achieving daily quality assurance and field correction from the regular scanned images.

 174 15:09 An empirical $B^-_1$ Non-uniformity Correction of Phased-Array Coil Images without Measuring Coil Sensitivity Frederick C Damen1 and Kejia Cai1 1Radiology, University of Illinois at Chicago Medical Center, Chicago, IL, United States Radio Frequency (RF) receiving coil arrays improve the signal-to-noise ratio (SNR), and enable partial parallel imaging. However, these benefits often come at the cost of image non-uniformity.  $B^-_1$ non-uniformity correction techniques are confounded by signal that not only varies due to coil induced $B^-_1$ sensitivity, but also due to true signal variations in proton density, susceptibility, and relaxation rates. Herein, we propose an empirical method that produces a $B^-_1$ non-uniformity-corrected complex image from the phased-array coil images themselves using minimal assumptions and without measuring the coil sensitivities. This method is validated using MRI of the abdomen, brain, and a homogeneous phantom.

 175 15:21 Improved image quality for long readout imaging using piecewise linear field map model Giang-Chau Ngo1, Alex Cerjanic1, and Bradley P. Sutton1,2 1Bioengineering Department, University of Illinois at Urbana-Champaign, Urbana, IL, United States, 2Beckman Institute, University of Ilinois at Urbana-Champaign, Urban, IL, United States Trajectories such as spiral or EPI enable fast acquisition compared to spin warp imaging. While a spin warp acquisition has a readout of 2-3 ms, a spiral trajectory readout can be as long as 60 ms. The efficiency of the spiral trajectory comes at a cost of image quality through magnetic field inhomogeneity and T2* decay during long readouts. In this work, a signal model with a piecewise linear field map is used to correct for the magnetic field inhomogeneity effects during long imaging readouts . The proposed method shows the ability to correct for resulting image artifacts.

 176 15:33 Measuring MRI Gradient Trajectory Dynamics using Simultaneous EEG-FMRI Mark Chiew1, Jostein Holmgren1, Dean Fido1, Catherine E Warnaby1, and S Johanna Vannesjo1 1Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom Simultaneous EEG-FMRI data acquisition provides an opportunity for characterization of magnetic field dynamics during imaging, by leveraging the information contained in the EEG induced gradient artefacts. Using a simple effective loop model, we reduce the complex EEG electrode geometry to small effective loops located at off-isocentre positions, which we use to fit first order (linear in space) models of the magnetic field rate of change. From these, estimates of the actual field dynamics, and trajectory/encoding information can be derived at no cost. In this proof-of-principle, we demonstrate estimation of gradient dynamics during a conventional EPI acquisition using simultaneous EEG recordings.

Oral

### Quantitative Neurovascular Imaging Methods

 S04 Monday 13:45 - 15:45 Moderators: John Detre & Sung-Hong Park

 177 13:45 Interleaved qBOLD: Combining Extravascular R2’ and Intravascular R2 Mapping for Improved Estimation of Brain Hemodynamic Parameters Hyunyeol Lee1 and Felix W Wehrli1 1Radiology, University of Pennsylvania, Philadelphia, PA, United States In qBOLD, the accuracy of local deoxygenated blood volume (DBV) and hemoglobin oxygen saturation (Yv) maps is impaired because of coupling of these two parameters in the signal model. Here, we introduce an interleaved qBOLD method that combines extravascular R2’ and intravascular R2 mapping in a single pulse sequence. Prior knowledge for DBV and Yv is obtained from the velocity-selective-spin-labeling module in the sequence, subsequently used as priors for qBOLD processing. Data obtained in eight subjects demonstrates significantly improved performance yielding plausible values averaging 60.1±3.3% for Yv and 3.1±0.5% and 2.0±0.4% for DBV in gray and white matter, respectively.

 178 13:57 Multi-delay arterial spin labeling (ASL) more accurately detects hypoperfusion in Moyamoya disease: comparison with a normative PET/MRI database Audrey P. Fan1, Mohammad M. Khalighi2, Jia Guo1, Yosuke Ishii1, Mirwais Wardak1, Jun-Hyung Park1, Bin Shen1, Dawn Holley1, Harsh Gandhi1, Prachi Singh1, Tom Haywood1, Gary K. Steinberg3, Frederick T. Chin1, and Greg Zaharchuk1 1Radiology, Stanford University, Stanford, CA, United States, 2GE Healthcare, Menlo Park, CA, United States, 3Neurosurgery, Stanford University, Stanford, CA, United States We directly compared multi-delay arterial spin labeling (ASL) and standard ASL measurements of cerebral blood flow (CBF) to simultaneously acquired [15O]-PET scans on hybrid PET/MRI in Moyamoya disease. For these Moyamoya patients (N=15) with extremely long arterial transit times, multi-delay ASL outperforms standard ASL in regional correlation and reduces bias relative to PET. We also constructed a voxelwise, normative CBF database based on healthy controls (N=15) with PET/MRI, and identified regions of hypoperfusion in frontal and parietal regions of patients. Multi-delay ASL is more specific to areas of Moyamoya hypoperfusion (more similar to PET), whereas standard ASL overestimates these areas due to low signal.

 179 14:09 Cerebral Metabolic Rate of Oxygen (CMRO2) mapping by a joint model of quantitative susceptibility mapping (QSM)-based method and quantitative BOLD (qBOLD) Junghun Cho1, Youngwook Kee2, Pascal Spincemaille2, Thanh Nguyen2, Jingwei Zhang1, Ajay Gupta2, Shun Zhang2,3, and Yi Wang1,2 1Biomedical Engineering, Cornell University, Ithaca, NY, United States, 2Radiology, Weill Cornell Medical College, New York, NY, United States, 3Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China In this work, we propose a gradient echo (GRE) based measurement of oxygen extraction fraction (OEF) based on a simultaneous modeling of the magnitude (using quantitative BOLD corrected for non-blood tissue susceptibility) and phase (based on QSM), without additional vascular challenges and empirical assumptions. Compared to methods based on QSM only and on qBOLD only, the proposed model provided better CMRO2 contrast between gray and white matter, and more uniform OEF in healthy subjects.

 180 14:21 3D MRI Mapping of Whole-Brain Water Permeability with Intrinsic Diffusivity Encoding of Arterial Labeled Spins (IDEALS) Xiang He1, Kenneth T Wengler2, Tim Q Duong1, and Mark Schweitzer1 1Radiology, Stony Brook University Hospital, Stony Brook, NY, United States, 2Biomedical Engineering, Stony Brook University, Stony Brook, NY, United States Breakdown of the blood-brain barrier has been hypothesized as a key mechanism leading to neuronal dysfunction that underlies many neurological and psychiatric diseases. Compared with exogenous contrast agents, trans-capillary water permeability may provide a more direct and sensitive assessment of BBB integrity at disease onset and progression. While the current gold standard approach to measure water permeability is O15-H2O PET, its widespread use is limited by availability and cost. Here, we propose a novel MRI-based method, IDEALS, to non-invasively map BBB water permeability with high sensitivity and whole-brain coverage. This method was applied in healthy participants and brain tumor patients.

 181 14:33 Identify the neurovascular coupling efficacy of long-term depolarization or seizer-like events in the hippocampus with optogenetic single-vessel fMRI Xuming Chen1,2,3, Filip Sobczak1,4, Yi Chen1,4, and Xin Yu1 1High-Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Tuebingen, Germany, 2University of Tuebingen, Tuebingen, Germany, 3Neurology, Renmin Hospital of Wuhan Universit, Wuhan University, Wuhan, China, 4Graduate Training Centre of Neuroscience, University of Tuebingen, Tuebingen, Germany Optogenetic activation can elicit seizure-like events in the hippocampus of anesthetized rats. However, it remains unclear how the hemodynamic signaling responds to the seizure-like events or long-term depolarization in hippocampus. Here, we applied the multi-model fMRI platform to acquire concurrent single-vessel fMRI and calcium signal upon optogenetic stimulation in the hippocampus. The neurovascular coupling coefficient was significantly lower for the long-term depolarization/seizure-like calcium event than that of normally evoked events. The reduced neurovascular coupling efficacy during seizure-like events indicates the lack of sufficient blood supply under high-energy demand of long-term depolarization, and eventually causes tissue damage.

 182 14:45 Black-blood angiography of the lenticulostriate artery at 3T using a high-resolution intracranial vessel wall MR technique: a comparison validation with 7T TOF-MRA Zihao Zhang1,2, Zhaoyang Fan3, Qingle Kong1,2,4, Jing An5, Yan Zhuo1,2, and Qi Yang6 1State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China, 2The Innovation Center of Excellence on Brain Science, Chinese Academy of Sciences, Beijing, China, 3Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States, 4University of Chinese Academy of Sciences, Beijing, China, 5Siemens Shenzhen Magnetic Resonance Ltd., Shenzhen, China, 6Xuanwu Hospital, Beijing, China The lenticulostriate artery (LSA) supplies blood to the basal ganglia and its vicinity. Noninvasive imaging of the LSA could be clinically useful to understand mechanisms of microvascular pathology or guide early therapeutic intervention. In this study, we used a recently developed high-resolution intracranial vessel wall MR imaging technique to visualize the LSA in a black-blood (BB) fashion at 3T. Compared to 7T TOF-MRA, this approach can depict the LSA, particularly the stems and proximal segments, with comparable image quality.

 183 14:57 Periventricular cerebral blood flow: A biomarker for small vessel ischemia Sudipto Dolui1,2, Marta Vidorreta2,3, David A. Wolk2, and John A. Detre1,2 1Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States, 3Siemens Healthineers, Madrid, Spain We evaluated periventricular white matter (PVWM) cerebral blood flow (CBF) as a mechanistically specific biomarker for small vessel ischemia and demonstrated the feasibility of its measurement using state-of-the-art arterial spin labeling. We constructed the PVWM region of interest and demonstrated that mean CBF in PVWM had higher correlation with lesion volumes than global, grey matter, or white matter CBF, even after correction for global CBF, age, and sex. PVWM CBF also showed higher correlation with Trail A and B processing speed than CBF in other regions, or lesion volumes.

 184 15:09 Quantification of flow hemodynamics using non-contrast enhanced 4-dimensional dynamic magnetic resonance angiography Xingfeng Shao1, Danny J.J. Wang1, and Lirong Yan1 1Laboratory of FMRI Technology (LOFT), Mark & Mary Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States Arterial spin labeling (ASL)-based non-contrast enhanced dynamic MR angiography (NCE-dMRA) can provide not only dynamic flow depiction but also quantitative hemodynamics.  According to the indicator dilution theory, we proposed a novel analytical solution for arterial blood flow (aBF) quantification in NCE-dMRA. Compared to the previous truncated singular value decomposition (t-SVD), reliable aBF measures were obtained using the proposed method from both simulation and experimental data. Hemodynamic maps including aBF, arterial blood volume and arterial transit time were successfully generated. Our preliminary patient data suggest that the dynamic flow patterns in conjunction with quantitative hemodynamic may provide complementary information for clinical diagnosis.

 185 15:21 Investigation of Intracranial Artery Selective Visualization in Superselective 4D-MR Angiography with Pseudo-Continuous Arterial Spin Labeling Combined with CENTRA-Keyhole and View-sharing (SS-4D-PACK) Makoto Obara1, Osamu Togao2, Helle Michael3, Tetsuhiro Wada4, Hiroo Murazaki4, Masami Yoneyama1, Yuta Akamine1, and Marc Van Cauteren5 1Philips Japan, Tokyo, Japan, 2Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan, 3Philips Research, Hamburg, Germany, 4Division of Radiology, Department of Medical Technology, Kyushu University Hospital, Fukuoka, Japan, 5Philips Healthtech, Tokyo, Japan Four dimensional (4D) MR Angiography with Pseudo-Continuous Arterial Spin Labeling (pCASL) combined with CENTRA-Keyhole and View-sharing (4D-PACK) has demonstrated high flow visualization ability in clinical use. In this study, we combined Superselective-pCASL with 4D-PACK (SS-4D-PACK) and investigated artery-selective visualization ability in SS-4D-PACK through comparison with contrast inherent inflow enhanced multi-phase angiography combining vessel-selective arterial spin labeling technique (CINEMA-Select). SS-4D-PACK showed higher vessel selectivity and vessel visualization in peripheral artery compared with CINEMA-Select.

 186 15:33 Acceleration of Vessel-Selective 4D MR Angiography by pCASL in combination with Acquisition of Control and Labeled Images in the Same Shot (ACTRESS) Yuriko Suzuki1, Thomas W. Okell2, and Matthias J.P. van Osch1 1C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, Netherlands, 2FMRIB Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom In the last decade, MR dynamic angiography (4D-MRA) using arterial spin labeling has become an important alternative to contrast-enhanced 4D-MRA, although scan-time is usually much longer than contrast-enhanced 4D-MRA. Among other advantages, it has the attractive possibility to allow for vessel-selective visualization. In this study, we propose an adaptation of ACTRESS (Acquisition of ConTRol and labeled Images in the Same Shot) approach for pCASL to enable vessel-selective 4D-MRA with almost halved scan-time. In an in-vivo study, it was shown that pCASL-ACTRESS approach provided vessel-selective 4D-MRA with comparable image quality to a conventional pCASL-approach, but acquired in approximately half the scan-time.

Oral

### Magnetic Susceptibility Imaging

 S06 Monday 13:45 - 15:45 Moderators: Jürgen Reichenbach & Masaki Fukunaga

 187 13:45 Direct Imaging of Diamagnetic Susceptibility of Beta Amyloid Aggregates in Transgenic Mouse Models of Alzheimer’s Disease using Quantitative Susceptibility Mapping MRI Nan-Jie Gong1,2, Russell Dibb2, and Chunlei Liu1,2 1University of California Berkeley, Berkeley, CA, United States, 2Duke University School of Medicine, Durham, NC, United States We demonstrated in a phantom that beta amyloid is diamagnetic and can generate strong contrast on susceptibility maps. Based on this, it is further shown both in vivo and ex vivo that magnetic susceptibility mapping could be used to monitor accumulation of amyloid plaques in AD mouse models. Most importantly, the diamagnetic susceptibility map and paramagnetic susceptibility map provided histology-like image contrast for identifying deposition of beta amyloid plaques and iron.

 188 13:57 Iron-induced relaxation mechanisms in the human substantia nigra: towards quantifying iron load in dopaminergic neurons Malte David Brammerloh1,2, Isabel Weigelt3, Thomas Arendt3, Filippos Gavriilidis2, Nico Scherf2, Steffen Jankuhn4, Markus Morawski3, Nikolaus Weiskopf2, and Evgeniya Kirilina2 1Faculty of Physics and Earth Sciences, Leipzig University, Leipzig, Germany, 2Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, 3Paul Flechsig Institute of Brain Research, Leipzig, Germany, 4Felix Bloch Institute for Solid State Physics, Leipzig University, Leipzig, Germany Pathological iron accumulation in the human brain is a biomarker for neurodegeneration. Several diagnostically promising MR-based methods for in vivo iron quantification were proposed, based on the empirical relationship between R2* and iron concentration. However, these do not account for different chemical forms and cellular distribution of iron. We combined post mortem MRI, advanced quantitative histology and biophysical modeling to develop a generative theory linking obtained iron concentrations to quantitative MR parameters. The impact of nanoscale molecular interaction of water with iron and of iron-rich dopaminergic neurons was quantified in substantia nigra.

 189 14:09 Accurate and Efficient QSM Reconstruction using Deep Learning Enhao Gong1, Berkin Bilgic2, Kawin Setsompop2, Audrey Fan3, Greg Zaharchuk3, and John Pauly1 1Electrical Engineering, Stanford University, Stanford, CA, United States, 2Harvard Medical School, Boston, MA, United States, 3Radiology, Stanford University, Stanford, CA, United States Quantitative Susceptibility Mapping (QSM) is a powerful MRI technique to quantify susceptibility changes and reveal pathology such as multiple sclerosis (MS) lesions and demyelination. QSM reconstruction is very challenging because it requires solving an ill-posed deconvolution and removing the effects of a dipole kernel on tissue phases to obtain susceptibility. To address the limitations of existing QSM reconstruction methods in accuracy, stability and efficiency, an iteration-free data-driven QSM reconstruction is proposed that trains a deep learning model to approximate COSMOS QSM quantification from acquired signals and pre-processed phases. Cross-validated on in-vivo datasets with 15 single direction QSM scans and 3 COSMOS QSM results from 3 healthy subjects, the proposed deep learning method achieves accurate QSM reconstruction, outperforming state-of-the-art methods across various metrics. The deep learning solution is also faster than iterative reconstruction by several orders of magnitude, which enables broader clinical applications.

 190 14:21 Quantitative susceptibility mapping using deep neural network Jaeyeon Yoon1, Jingyu Ko1, Jingu Lee1, Hosan Jung1, Berkin Bilgic2, Kawin Setsompop2, and Jongho Lee1 1Department of Electrical and Computer Engineering, Seoul National University, Seoul, Republic of Korea, 2Department of Radiology, Harvard Medical School, Boston, MA, United States In this study, we designed a deep neural network that functions as dipole deconvolution in QSM reconstruction. For label data, COSMOS reconstructed QSM maps were used so that the network produces ground truth like COSMOS results without streaking artifacts. The performance of our network was superior to conventional QSM results with lower RMSE for multiple head orientation input data.

 191 14:33 Vertebral Column Quantitative Susceptibility Mapping using Joint Background Field Removal and Dipole Inversion Maximilian N. Diefenbach1, Anh Van2, Jakob Meineke3, Andreas Scharr4, Jan S. Kirschke4, Alexandra Gersing1, Thomas Baum4, Benedikt Schwaiger1, and Dimitrios C. Karampinos1 1Diagnostic and Interventional Radiology, Technical Univeristy of Munich, Munich, Germany, 2Institute of Medical Engineering, Technical University of Munich, Munich, Germany, 3Philips Research Laboratory, Hamburg, Germany, 4Department of Diagnostic and Interventional Neuroradiology, Technical University of Munich, Munich, Germany Quantitative susceptibility mapping (QSM) with joint background field removal and dipole inversion is applied in the spine of osteoporosis patients and healthy volunteers. Preliminary multi-MR-parametric patient results are compared to low-dose CT scans to investigate the feasibility of QSM to qualitatively and quantitatively detect features of diseased tissues and differentiate positive and negative susceptibility sources in comparison to R2*-mapping.

 192 14:45 Microscopic susceptibility anisotropy imaging: A clinically viable gradient-echo MRI technique Enrico Kaden1, Umesh Rudrapatna2, Irina Y. Barskaya3, Mark D. Does3, Derek K. Jones2, and Daniel C. Alexander1 1Centre for Medical Image Computing, Department of Computer Science, University College London, London, United Kingdom, 2Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, United Kingdom, 3Institute of Imaging Science, Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, United States The orientation dependence of the gradient-echo MR signal in brain white matter conflates two principal effects, (i) the susceptibility properties of tissue microenvironments, especially the myelin microstructure, and (ii) the axon orientation distribution with respect to the external magnetic field. This work introduces a clinically feasible MRI method based on gradient-echo and diffusion measurements, which we refer to as microscopic susceptibility anisotropy imaging, that disentangles both effects, hence enabling us to estimate microscopic susceptibility anisotropy unconfounded by fibre crossings and orientation dispersion as well as magnetic field direction.

 193 14:57 How should we compare QSM results? A correlation based analysis as an alternative to traditional error metrics Jiaen Liu1 and Pinar S Özbay1 1Advanced MRI Section, LFMI, NINDS, National Institutes of Health, Bethesda, MD, United States During the last QSM Workshop, the results of first “Quantitative Susceptibility Mapping (QSM) Reconstruction Challenge” were presented, which was performed to allow a systematic comparison of various QSM algorithms. One unresolved issue was the fact that the comparison metrics did not properly deal with the effect of smoothing. Here, we propose a comparison method based on pearson correlations, which are calculated over 1D lines throughout the QSM volumes, and show its robustness relative to other metrics under the influence of over-smoothing.

 194 15:09 Age- and sex-related spatial patterns of variation in normal brain magnetic susceptibility (QSM) revealed by Blind Source Separation (BSS) and Supervised Machine Learning Ferdinand Schweser1,2, Balint Sule1, Juliane Damm1, Niels P Bergsland1,3, Michael G Dwyer1, Akshay V Dhamankar1, Bianca Weinstock-Guttman4, and Robert Zivadinov1,2 1Buffalo Neuroimaging Analysis Center, Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, NY, United States, 2Center for Biomedical Imaging, Clinical and Translational Science Institute, University at Buffalo, The State University of New York, Buffalo, NY, United States, 3MR Research Laboratory, IRCCS, Don Gnocchi Foundation ONLUS, Milan, Italy, 4BairdMS Center, Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, NY, United States Previous studies using QSM have demonstrated a relatively high inter-subject variation of brain susceptibility. In the present work, we combined a blind source separation technique with a machine learning strategy to disentangle spatial networks of independent variation of brain susceptibility. As a first step toward a better understanding of the underlying causes of variation, we studied their associations with age and sex. The analysis revealed several networks with distinct anatomical features, although the applied analysis technique did not involve any information about anatomy, age, or sex.

 195 15:21 Constrained Dipole Inversion for Quantitative Susceptibility Mapping Using a "Kernel+Sparse" Model Xi Peng1,2, Yudu Li1,3, Fan Lam1, Rong Guo1,3, Bryan Clifford1,3, and Zhi-Pei Liang1,3 1Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States, 2Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Shenzhen, China, 3Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, United States In quantitative susceptibility mapping (QSM), constrained dipole inversion is often necessary to overcome the ill-posedness of the underlying dipole deconvolution problem. Existing methods achieve this by the use of spatial regularization. In this work, we propose a novel "kernel+sparse" model for constrained dipole inversion. In this model, the kernel term absorbs the prior information by representing the susceptibility as a function of prior features while the sparse term accounts for the localized novel features. The proposed method has been evaluated using both simulated and in vivo data, producing impressive results. This method may prove to be useful for many QSM studies.

 196 15:33 Sensitivity of Relaxometry and Quantitative Susceptibility Mapping to Microscopic Iron Distribution Timothy J Colgan1,2, Gesine Knobloch1, Scott B Reeder1,2,3,4,5, and Diego Hernando1,2 1Radiology, University of Wisconsin - Madison, Madison, WI, United States, 2Medical Physics, University of Wisconsin - Madison, Madison, WI, United States, 3Medicine, University of Wisconsin - Madison, Madison, WI, United States, 4Biomedical Engineering, University of Wisconsin - Madison, Madison, WI, United States, 5Emergency Medicine, University of Wisconsin - Madison, Madison, WI, United States MRI-based iron quantification enables the non-invasive assessment of tissue iron concentration. MRI relaxation parameters such as R2 and R2* are sensitive to iron concentration, but may depend on the microscopic spatial distribution of iron. Quantitative Susceptibility Mapping (QSM) is a promising iron quantification technique, but its sensitivity to the spatial distribution of iron remains unknown.  In this work, we performed simulations and in vitro experiments using whole versus lysed erythrocytes to investigate this sensitivity. Our results suggest that QSM, unlike R2 and R2* relaxometry, is independent of the microscopic distribution of iron.

Oral

### Loose Cartilage

 W03/04 Monday 13:45 - 15:45 Moderators: Jeff Dunn & Konstantin Momot

 197 13:45 Correlations of T1ρ with properties of articular cartilage depend on the spin-lock amplitude and orientation of the sample Mikko Johannes Nissi1, Isabel Stavenuiter1,2, and Nina Hänninen3 1Department of applied physics, University of Eastern Finland, Kuopio, Finland, 2Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands, 3Research Unit of Medical Imaging, Physics and Technology, University of Oulu, Oulu, Finland Several studies have reported different findings on the correlations of the CW-T1ρ relaxation time in articular cartilage with its different properties. Most studies agree on the sensitivity of CW-T1ρ to cartilage proteoglycans, although reports specifically against this also exist. Furthermore, CW-T1ρ has been connected to the collagen network properties and also correlated with T2 relaxation time. Orientation dependence of CW-T1ρ has been reported, as well as its dependence on the spin-locking amplitude. This study aims to combine all of these aspects in a single study.

 198 13:57 Using Multidimensional Data Analysis to Identify Traits of Hip OA Jasmine Rossi-deVries1, Valentina Pedoia1, Michael A Samaan1, Adam Ferguson1, Richard B Souza1, and Sharmila Majumdar1 1UCSF, San Francisco, CA, United States This study aims to use big data analytics and imaging to simultaneously analyze all the combined variables in order to identify biomarkers able to classify the different disease progression of hip OA. 102 subjects and their 184 variables were examined. Big data analytics tool, Topological Data Analysis (TDA), was used to generate hypotheses. Three main groups were identified: healthy control subjects, subjects with radiographic and morphological evidence of OA, and subjects who progressed inconsistently were separated by knee biomechanics. The analysis obtained with TDA proposes new phenotypes of these subjects also shows the potential for further examination.

 199 14:09 T2 Texture Analysis Reveals Potential Cartilage-preserving Effect in Presence of Heterozygous WNT1 Mutation in Human Sami Lehtovirta1,2, Riikka E Mäkitie3, Victor Casula1,2, Marianne Haapea1, Jaakko Niinimäki1,2, Tuukka Niinimäki4, Arttu Peuna2, Eveliina Lammentausta2, Outi Mäkitie3,5,6, and Miika T Nieminen1,2 1Research Unit of Medical Imaging, Physics and Technology, University of Oulu, Oulu, Finland, 2Medical Research Center, University of Oulu and Oulu University Hospital, Oulu, Finland, 3Folkhälsan Institute of Genetics and University of Helsinki, Helsinki, Finland, 4Department of Orthopedics, Oulu University Hospital, Oulu, Finland, 5Children’s Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland, 6Center for Molecular Medicine, Karolinska Institutet, and Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden Quantitative MRI (qMRI) assessment of tibiofemoral articular cartilage was performed in 13 WNT1 mutation-positive (MP) subjects and 13 mutation-negative (MN) controls. Cartilage thickness, T2 and T1r relaxation times, and texture features contrast, homogeneity and dissimilarity of T2 maps were determined in six regions of interests. Texture features demonstrated an opposing trend with age between the two groups in medial tibiofemoral cartilage, suggesting a possible age-related cartilage preservation in MP subjects. Similar differences were not observed in the other qMRI parameters, suggesting that texture analysis is a more sensitive and accurate tool for quantitative cartilage assessment than mere mean relaxation time measurements.

 200 14:21 Can A Machine Diagnose Knee MR Images? Fully-automated Cartilage Lesion Detection by using Deep Learning Fang Liu1, Zhaoye Zhou2, Kevin Lian1, Shivhumar Kambhampati1, and Richard Kijowski1 1Department of Radiology, University of Wisconsin-Madison, Madison, WI, United States, 2Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, United States This study evaluated a fully-automated cartilage lesion detection system utilizing a deep convolutional neural network (CNN) to segment bone and cartilage followed by a second CNN classification network to detect structural abnormalities within the segmented tissues. The CNN network was trained to detect cartilage lesions within the knee joint using sagittal fat-suppressed T2-weighted fast spin-echo images in 125 subjects. The proposed CNN model achieved high diagnostic accuracy for detecting cartilage lesions with a 0.914 area under curve on receiver operation characteristics analysis. The optimal threshold for sensitivity and specificity of the CNN model was 84.3% and 84.6% respectively.

 201 14:33 Automated Knee Cartilage Segmentation with Very Limited Training Data: Combining Convolutional Neural Networks with Transfer Learning Alexander R Toews1,2, Zhongnan Fan3, Marianne S Black2,4, Jin Hyung Lee1,3,5,6,7, Garry E Gold2,5,8, Brian A Hargreaves1,2,5, and Akshay S Chaudhari2,5 1Electrical Engineering, Stanford University, Stanford, CA, United States, 2Radiology, Stanford University, Stanford, CA, United States, 3LVIS Corporation, Palo Alto, CA, United States, 4Mechanical Engineering, Stanford University, Stanford, CA, United States, 5Bioengineering, Stanford University, Stanford, CA, United States, 6Neurology & Neurological Sciences, Stanford University, Stanford, CA, United States, 7Neurosurgery, Stanford University, Stanford, CA, United States, 8Orthopaedic Surgery, Stanford University, Stanford, CA, United States Magnetic resonance imaging is commonly used to study osteoarthritis. In most cases, manual cartilage segmentation is required. Recent advances in deep-learning methods have shown promise for automating cartilage segmentation, but they rely on the availability of large training datasets that rarely represent the exact nature or extent of data practically available in routine research studies. The goal of this study was to automate cartilage segmentation in studies with very few training datasets available by creating baseline segmentation knowledge from larger training datasets, followed by creating transfer learning models to adapt this knowledge to the limited datasets utilized in typical study.

 202 14:45 Isotropic 3D T2 mapping of knee cartilage with a novel water excitation technique Roberto Colotti1, Jessica A.M. Bastiaansen1, Patrick Omoumi1, and Ruud B. van Heeswijk1,2 1Department of Radiology, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland, 2Center for Biomedical Imaging (CIBM), Lausanne, Switzerland The goal of this study was to develop an isotropic 3D lipid-insensitive T2 mapping technique of knee cartilage. Therefore we combined an existing isotropic 3D T2-prepared gradient-echo T2 mapping technique (Iso3DGRE) with the novel lipid-insensitive binomial off-resonant RF excitation (LIBRE) pulse. LIBRE pulse optimization was performed through numerical simulations and verified in phantom experiments, yielding complete fat signal nulling using a LIBRE pulse as short as 1 ms. T2 mapping of knee cartilage performed in five healthy volunteers with LIBRE excitation allowed for improved cartilage delineation and precise T2 values compared with normal excitation.

 203 14:57 Accelerating 3D-Biexponential T1ρ Mapping of Cartilage using Compressed Sensing with Different Regularizations Marcelo V. W. Zibetti1, Azadeh Sharafi1, Ricardo Otazo1, and Ravinder R. Regatte1 1Center for Biomedical Imaging, New York University School of Medicine, New York, NY, United States Quantitative T1ρ imaging usually requires multiple spin-lock times to obtain T1ρ maps, which makes the acquisition time demanding especially for biexponential models. Compressed Sensing has demonstrated significant acquisition time reduction in MRI. Similar improvements are expected for T1ρ relaxation mapping, given the extensive correlations in the series of images. However, it is not clear which combination of sparsifying transform and regularization function performs best for biexponential T1ρ mapping. Here, we compare five CS approaches: l1-norm of principal component analysis, spatio-temporal finite differences, exponential dictionaries, low rank, and low rank plus sparse. Our preliminary results, with three datasets, suggest that L+S is the most suitable method with least T1ρ estimation error.

 204 15:09 UTE-T2* Shows Deep Cartilage Subsurface Matrix Changes 2 Years After ACL Reconstruction Ashley Williams1,2, Matthew Titchenal1,2, Aditi Guha1,2, Bao H. Do2,3, and Constance R Chu1,2 1Department of Orthopaedic Surgery, Stanford University, Stanford, CA, United States, 2Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, United States, 3Department of Radiology, Stanford University, Stanford, CA, United States The purpose of this study is to compare 2-D and 3-D assessments of UTE-T2* maps for evidence of alterations to the subsurface cartilage matrix suggestive of cartilage at risk for early OA  2 years after ACL reconstruction. UTE-T2* values from small 2-D, single slice ROIs correlated to 3-D ROI values that encompassed a larger degree of weight-bearing cartilage. Results indicate that single slice 2-D UTE-T2* mapping may be an efficient means to assess the medial femoral cartilage as an imaging marker of pre-osteoarthritis while 3-D assessments provide additional sensitivity to changes in the tibial plateau.

 205 15:21 Local associations between intervertebral disc T1rho/T2, muscle health, physical activity, and clinical disability using voxel-based relaxometry Claudia Iriondo1, Valentina Pedoia2, Jason Talbott2, William Dillon2, and Sharmila Majumdar2 1UCSF/UC Berkeley Graduate Program in Bioengineering, University of California, San Francisco, San Francisco, CA, United States, 2Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States Region of interest based analysis of intervertebral disc composition in low back pain populations is (1) time-consuming and (2) limited in reproducibility, even more so in patients with advanced degeneration. This study applies voxel-based relaxometry (VBR) to investigate the spatial distributions of T1ρ and T2 in lumbar intervertebral discs, and their association to patient reported outcomes and spinal muscle health. Our results demonstrate the potential to use VBR as a tool to more effectively measure biochemical differences in the intervertebral discs across low back pain subgroups and monitor changes over time.

 206 15:33 Quantitative MRI in early intervertebral disc degeneration: T1rho correlates better than T2 and ADC with biomechanics and matrix content Cornelis Paul1, Theodoor Smit1, Magda de Graaf2, Roderick Holewijn2, Arno Bischop2, Peter van de Ven3, Margriet Mullender4, Marco Helder5, and Gustav Strijkers6 1Orthopedic Surgery, Academic Medical Center, Amsterdam, Netherlands, 2Orthopedic Surgery, VU University Medical Center, Amsterdam, Netherlands, 3Epidemiology and Biostatistics, VU University Medical Center, Amsterdam, Netherlands, 4Plastic, Reconstructive and Hand Surgery, VU University Medical Center, Amsterdam, Netherlands, 5Oral and Maxillofacial Surgery, VU University Medical Center, Amsterdam, Netherlands, 6Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, Netherlands We correlated quantitative T2, T1rho and Apparent Diffusion Coefficient (ADC) values to disc mechanical behavior and gold standard early DDD markers in a graded degenerated lumbar IVD caprine model to assess their potential for early DDD detection. T1rho nucleus values correlate better than T2 and ADC with biomechanical, histological, and GAG changes.

Study Groups

 W08 Monday 14:45 - 15:45 (no CME credit)

 Exhibition Hall 1509-1553 Monday 16:15 - 18:15 (no CME credit)

Electronic Poster: Molecular Imaging

 Exhibition Hall Monday 16:15 - 17:15 (no CME credit)

Electronic Poster: Neuro

 Exhibition Hall Monday 16:15 - 17:15 (no CME credit)

Study Groups

 W07 Monday 16:15 - 17:15 (no CME credit)

Study Groups

### MR in Drug Research Business Meeting

 W08 Monday 16:15 - 17:15 (no CME credit)

Member-Initiated Symposium

### Safety & Efficacy of Contrast Agents: State of the Art, Future Directions, & Alternative Approaches

Organizers: Peter Caravan, Ira Krefting

 N01 Monday 16:15 - 18:15 Moderators: Tim Leiner (no CME credit)

 16:15 State of the Art on Gd Deposition: Science, Clinical & Regulatory Reaction Henrik Thomsen

 16:30 What Do We Still Need to Know About GBCAs? A Roadmap for Further Studies Karen Bleich1 1FDA

 16:45 Q & A

 16:55 Can Contrast-Enhanced MR Be Replaced? Non-Contrast Methods, Ultra-Low-Dose Contrast & Where Contrast Is Essential Susie Huang1 1Massachusetts General Hospital, United States

 17:10 Gadolinium-Based Contrast Agents: State of the Art & Future Directions Silvio Aime1 1University of Torino, Italy

 17:25 Rust Never Sleeps: Iron as an Alternative to Gadolinium for Contrast-Enhanced Imaging Alexander Guimaraes1 1Oregon Health Sciences University, United States

 17:40 Metal-Free Contrast Agents Peter van Zijl

 17:55 Q & A

Member-Initiated Symposium

### Neurophysiological Basis of Resting-State Functional Connectivity: Evidence from Rodents, Monkeys to Humans

Organizers: Shella Keilholz, Hanbing Lu

 N02 Monday 16:15 - 18:15 Moderators: Shella Keilholz (no CME credit)

 16:15 Infraslow Electrical Activity & BOLD Oscillations Anzar Abbas1 1Neuroscience, Emory University, Atlanta, GA, United States

 16:39 Contribution of Vigilance Fluctuations to Resting-State fMRI Catie Chang1 1NINDS, NIH

 17:03 Electrophysiological Brain Networks: Insights from Magnetoencephalography (MEG) Matthew Brookes1 1University of Nottingham

 17:27 Global Cerebral Glucose Metabolism & the Global Signal from Resting-State fMRI Garth Thompson

 17:51 Panel Discussion

Weekday Course

### MR Physics & Techniques for Clinicians

Organizers: Marcus Alley, Bernd Jung

 S01 Monday 16:15 - 18:15 Moderators: Joseph Cheng & Bernd Jung

 16:15 Spin Gymnastics 1 & 2 Frank Korosec1 1University of Wisconsin - Madison, United States This educational lecture will provide a general overview of the basic physics of MRI. A broad range of topics will be covered, including magnetization and signal generation, relaxation of magnetization, the spin echo phenomenon, spatial encoding of signal, and a very brief introduction to the concept of k-space. Several of the topics will be introduced in this lecture and will be further elucidated by other presenters in this course.

 17:45 Image Quality Matthias Weigel1,2 1Division of Radiological Physics, Dept. of Radiology, University Hospital Basel, Basel, Switzerland, 2Dept. of Biomedical Engineering, University of Basel, Basel, Switzerland This educational talk presents an overview of key aspects influencing and quantitatively depicting image quality. Several examples for the different types of image quality aspects are given. The importance of signal-to-noise ratio (SNR) and the "triangle of death" for image quality in MRI is discussed in particular.

 18:15 Adjournment & Meet the Teachers

Weekday Course

### Quantitative MRI in MSK: From Acquisition to Application

Organizers: Eric Chang, Garry Gold, Edwin Oei, Philip Robinson

 W05/06 Monday 16:15 - 18:15 Moderators: Xiaojuan Li & Ashley Williams

 16:15 Relaxation Eveliina Lammentausta1 1Oulu University Hospital, Finland

 16:40 Standardization, Phantoms Kathryn Keenan1 1NIST, United States This talk will review how to design a phantom for MSK applications, how to develop standardization across platforms, and considerations for reproducibility and reliability studies.

 17:05 Image Processing, Machine Learning and Multimodal Data Analysis Valentina Pedoia1 1University of California, San Francisco, United States In this lecture, we provide an overview on the potential of coupling of cutting edge technologies in quantitative MRI, deep learning and big data analytics fields. The main goal is to show how those techniques can be applied to discover latent feature able to accurately characterize disease status and predict progression. The data-driven extraction of features from relaxation maps and multidimensional analysis of data from various sources can exploit the real potential of quantitative MRI technique, to date still hampered by tedious and time-consuming manual image post-processing pipelines; and deeply underused due to the handcrafting of too simplistic image representations.

 17:30 Common Pitfalls in Quantitative MSK MRI Emily McWalter1 1University of Saskatchewan, Canada

 17:55 Panel Discussion

 18:20 Adjournment & Meet the Teachers

Power Pitch

### Pitch: Pulse Sequence Highlights

 Power Pitch Theater A - Exhibition Hall Monday 16:15 - 17:15 Moderators: Oliver Bieri & Mark Chiew (no CME credit)

 207 16:15 Maxwell-compensated waveform design for asymmetric diffusion encoding Filip Szczepankiewicz1,2 and Markus Nilsson1 1Clinical Sciences, Lund, Lund University, Lund, Sweden, 2Random Walk Imaging AB, Lund, Sweden

 208 16:15 Spin And Field Echo (SAFE) dynamic field correction in 3T fetal EPI Lucilio Cordero-Grande1, Anthony Price1, Giulio Ferrazzi2, Jana Hutter1, Daan Christiaens1, Emer Hughes1, and Jo Hajnal1 1King's College London, London, United Kingdom, 2Physikalisch-Technische Bundesanstalt, Braunschweigh and Berlin, Germany

 209 16:15 Self-Gated and Real-time Simultaneous Multi-Slice Cardiac MRI from the Same Acquisition Sebastian Rosenzweig1, Hans Christian Martin Holme1,2, Nick Scholand1, Robin Niklas Wilke1,2, and Martin Uecker1,2 1Intistut für Diagnostische und Interventionelle Radiologie, University Medical Center Göttingen, Göttingen, Germany, 2Partner Site Göttingen, German Centre for Cardiovascular Research (DZHK), Göttingen, Germany

 210 16:15 Phase Encoded xSPEN: A High-Definition Approach to Volumetric MRI with Unusually High Acceleration Factors Zhiyong Zhang1, Michael Lustig2, and Lucio Frydman1 1Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel, 2Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, CA, United States

 211 16:15 Accelerated T2-Weighted Imaging of the Abdomen with Self-Calibrating Wave-Encoded 3D Fast Spin Echo Sequences Feiyu Chen1, Valentina Taviani2, Joseph Y. Cheng3, John M. Pauly1, and Shreyas S. Vasanawala3 1Electrical Engineering, Stanford University, Stanford, CA, United States, 2Global MR Applications and Workflow, GE Healthcare, Menlo Park, CA, United States, 3Radiology, Stanford University, Stanford, CA, United States

 212 16:15 Tilted-CAIPI for Highly Accelerated Distortion-Free EPI with Point Spread Function (PSF) Encoding Zijing Dong1, Fuyixue Wang2,3, Timothy G. Reese2, Mary Kate Manhard2, Berkin Bilgic2, Lawrence L. Wald2,3, Hua Guo1, and Kawin Setsompop2,3 1Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China, 2A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, United States, 3Harvard-MIT Health Sciences and Technology, MIT, Cambridge, MA, United States

 213 16:15 Silent MRF : Quantitative scan with reduced noise using the Magnetic Resonance Fingerprinting (MRF) framework Dan Ma1, Bhairav B Mehta1, and Mark A Griswold1 1Radiology, Case Western Reserve University, Cleveland, OH, United States

 214 16:15 Focused, High-Resolution, Distortion-Free Diffusion Imaging Myung-Ho In1, Yi Sui1, Joshua D Trzasko1, Yunhong Shu1, Shengzhen Tao1, Erin M Gray1, John Huston1, and Matt A Bernstein1 1Department of Radiology, Mayo Clinic, Rochester, MN, United States

 215 16:15 DP-TSE MRF: Rapid and Accurate T2 and ADC Quantification Using Diffusion-Prepared Turbo Spin-echo Magnetic Resonance Fingerprinting Zhixing Wang1,2, Xiaozhi Cao2, Congyu Liao2, Huihui Ye2,3, Hongjian He2, and Jianhui Zhong2 1Biomedical Engineering, University of Virginia, Charlottesville, VA, United States, 2Center for Brain Imaging Science and Technology, Department of Biomedical Engineering, Zhejiang University, Hangzhou, China, 3State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, China

 216 16:15 Shuttered EPI Brain Imaging at 7 Tesla Saikat Sengupta1, Kawin Setsompop2, and William A Grissom3 1Department of Radiology, Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, United States, 2Department of Radiology, A.A. Martinos Center for Biomedical Imaging, Harvard Medical School, Charlestown, MA, United States, 3Department of Biomedical Engineering, Vanderbilt University Institute of Imaging Science, Vanderbilt Univserity, Nashville, TN, United States

 217 16:15 Echo Planar Time-resolved Imaging (EPTI) Fuyixue Wang1,2, Zijing Dong3, Timothy G. Reese1, Berkin Bilgic1, Mary Kate Manhard1, Lawrence L. Wald1,2, and Kawin Setsompop1,2 1A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, United States, 2Harvard-MIT Health Sciences and Technology, MIT, Cambridge, MA, United States, 3Center for Biomedical Imaging Research, Department of Biomedical Engineering, Tsinghua University, Beijing, China

 218 16:15 TOPPE: A framework for rapid prototyping of MR pulse sequences Jon-Fredrik Nielsen1 and Douglas C Noll1 1Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States

 219 16:15 Time-optimal control based RF pulse design under gradient imperfections Christoph Stefan Aigner1, Armin Rund2, Samy Abo Seada3, Shaihan Malik3, Joseph V Hajnal3, Karl Kunisch2,4, and Rudolf Stollberger1 1Institute of Medical Engineering, Graz University of Technology, Graz, Austria, 2Institute for Mathematics and Scientific Computing, University of Graz, Graz, Austria, 3Division of Imaging Sciences and Biomedical Engineering, King's College London, London, United Kingdom, 4Johann Radon Institute for Computational and Applied Mathematics (RICAM), Austrian Academy of Sciences, Linz, Austria

 220 16:15 Fast multi-component T1 and T2 correlation measurements using steady-state free precession Julian Pfister1, Felix A. Breuer1, Peter M. Jakob2, and Martin Blaimer1 1Magnetic Resonance and X-ray Imaging Department, Fraunhofer Development Center X-ray Technology (EZRT), Würzburg, Germany, 2Experimental Physics 5, University of Würzburg, Würzburg, Germany

 221 16:15 MEG-Navigators for Motion Detection and Quality Assurance in MR Elastography Christian Guenthner1 and Sebastian Kozerke1 1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland

Power Pitch

 Power Pitch Theater B - Exhibition Hall Monday 16:15 - 17:15 Moderators: Xiaoqi Huang & Fei Li (no CME credit)

 222 16:15 Iron-related gene expression associated with magnetic susceptibility reductions: Application to the pathophysiology of a movement disorder population Ahmad Seif Kanaan1,2, Alfred Anwander1, Riccardo Metere1, Andreas Schäfer3, Torsten Schlumm1, Jamie Near4, Berkin Bilgic5, Kirsten Müller-Vahl2, and Harald Möller1 1Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, 2Department of Psychiatry, Hannover Medical School, Hannover, Germany, 3Siemens Healthcare, Erlangen, Germany, 4Douglas Mental Health Institute, McGill University, Montreal, QC, Canada, 5Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States

 223 16:15 Multimodal ASL/PET/mRNA-expression analysis reveals CBF changes after single dose of antipsychotics depend on dopamine D2 receptor density profiles. Pierluigi Selvaggi1, Mattia Veronese1, Peter C. T. Hawkins1, Ottavia Dipasquale1, Gaia Rizzo2,3, Juergen Dukart4, Fabio Sambataro5, Alessandro Bertolino6, Steven C.R. Williams1, Federico E Turkheimer1, and Mitul A. Mehta1 1Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom, 2Imanova Ltd., Centre for Imaging Sciences, Hammersmith Hospital, London, United Kingdom, 3Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK, London, United Kingdom, 4Translational Medicine Neuroscience and Biomarkers, F. Hoffmann-La Roche Ltd, Basel, Switzerland, 5Department of Experimental and Clinical Medical Sciences, University of Udine, Udine, Italy, 6Department of Basic Medical Science, Neuroscience and Sense Organs, University of Bari Aldo Moro, Bari, Italy

 224 16:15 Impaired modulation of hippocampal glutamate during memory consolidation in schizophrenia: Evidence from ¹H fMRS Jeffrey A. Stanley1, Patricia Thomas1, Dalal Khatib1, Asadur Chowdury1, Usha Rajan1, Luay Haddad1, Amirsadri Alireza1, and Vaibhav A. Diwadkar1 1Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI, United States

 225 16:15 N-acetyl-cysteine supplementation improves functional connectivity in the cingulate cortex in early psychosis Emeline Mullier1, Timo Roine1, Alessandra Griffa2, Philipp Baumann3, Philippe Conus4, Kim Q. Do4, and Patric Hagmann1 1Radiology, Lausanne University Hospital (CHUV), Lausanne, Switzerland, 2Dutch connectome lab, University Medical Center (UMC), Utrecht, Netherlands, 3Service of General Psychiatry and Center for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital (CHUV), Lausanne, Switzerland, 4Department of psychiatry, Lausanne University Hospital (CHUV), Lausanne, Switzerland

 226 16:15 Altered Brain Development in Infants and Young Children with at Risk Genetics for Psychiatric Dysfunction Justin Remer1,2, Douglas C. Dean III3, Muriel Bruchhage2,4, and Sean C.L. Deoni2 1Brown University Warren Alpert School of Medicine, Providence, RI, United States, 2Memorial Hospital, Brown University, Providence, RI, United States, 3Waisman Center, University of Wisconsin, Madison, WI, United States, 4Center for Neuroimaging, King's College, London, United Kingdom

 227 16:15 7T MRS in First Episode Psychosis: Neurotransmitter Deficits and Neuronal Impairment Anna Min Wang1,2, Subechhya Pradhan1,2, Akira Sawa3, and Peter B. Barker1,2 1Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, United States, 2Kennedy Krieger Institute, Baltimore, MD, United States, 3Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, United States

 228 16:15 A DTI connectome and machine learning approach to predict symptom improvement in depressed adolescents with cognitive-behavioral therapy (CBT) Olga Tymofiyeva1, Justin Yuan1, Colm G Connolly2, Eva Henje Blom3, Duan Xu1, and Tony Yang1 1University of California, San Francisco, San Francisco, CA, United States, 2Florida State University, Tallahassee, FL, United States, 3Umea University, Umea, Sweden

 229 16:15 Neural network classification of ADHD based on white matter connectograms derived from diffusion spectrum imaging Chang-Le Chen1,2, Yung-Chin Hsu1, Susan Shur-Fen Gau2,3, and Wen-Yih Isaac Tseng1,2,4 1Institute of Medical Device and Imaging, National Taiwan University College of Medicine, Taipei, Taiwan, 2Graduate Institute of Brain and Mind Sciences, National Taiwan University College of Medicine, Taipei, Taiwan, 3Department of Psychiatry, National Taiwan University Hospital, Taipei, Taiwan, 4Molecular Imaging Center, National Taiwan University, Taipei, Taiwan

 230 16:15 Hippocampal-subfield Specific Connectivity Alterations in Major Depressive Disorder Patients at 7 Tesla John W Rutland1, Prantik Kundu 1, Patrick R Hof2, James W Murrough3, and Priti Balchandani1 1Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 2Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 3Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, United States

 231 16:15 Reduced Local Segregation in Single-Subject Grey Matter Networks in Adult PTSD Running Niu1, Du Lei2, and Qiyong Gong3 1HMRRC, West China Hospital, Chengdu, China, China, 2Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, United Kingdom, London, United Kingdom, 3uaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan, Chengdu, China

 232 16:15 Sertraline treatment modulates salience connectivity in major depressive disorder Li-Ming Hsu1, Changwei W. Wu1, Chien-Yuan Lin2, Chi-Yun Liu1, Timothy Lane1, Ching-Po Lin3, Chi-Bin Yeh4, and Hung-Wen Kao4 1Brain and Consciousness Research Center, Taipei Medical University, Taipei, Taiwan, 2GE Healthcare, Taipei, Taiwan, 3National Yang-Ming University, Taipei, Taiwan, 4Department of Radiology, National Defense Medical Center, Taipei, Taiwan

 234 16:15 Abnormal Perfusion and Perfusion fluctuation in Bipolar Disorder measured by ASL Weiying Dai1, Mingzhao Chen1, Li Zhao2, Nicolas Bolo3, David C. Alsop2, and Keshavan Matcheri3 1State University of New York at Binghamton, BINGHAMTON, NY, United States, 2Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States, 3Department of Psychiatry, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States

 235 16:15 Elevated brain iron in cocaine addiction as indexed by magnetic field correlation imaging Vitria Adisetiyo1, Corinne E. McGill1, William DeVries2, Jens H. Jensen1,3, Colleen A. Hanlon2, and Joseph A. Helpern1 1Neuroscience, Medical University of South Carolina, Charleston, SC, United States, 2Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States, 3Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, United States

 236 16:15 Deletion of CRTC1 is associated with strong neuroenergetic dysfunctions in a mouse model of mood disorders. Antoine Cherix1, Guillaume Donati1, Blanca Lizarbe1, Hongxia Lei2, Carole Poitry-Yamate2, Jean-René Cardinaux3, and Rolf Gruetter1,4,5 1Laboratory for Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, 2Animal Imaging and Technology Core (AIT), Center for Biomedical Imaging (CIBM), Ecole Polytechnique Fédérale de Lausanne., Lausanne, Switzerland, 3Center for Psychiatric Neuroscience (CNP), Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland, 4Department of Radiology, University of Geneva, Geneva, Switzerland, 5Department of Radiology, University of Lausanne, Lausanne, Switzerland

Combined Educational & Scientific Session

### Liver Imaging: What Can We Really Quantify?

Organizers: Kathryn Fowler

 S02 Monday 16:15 - 18:15 Moderators: Sudhakar Venkatesh & Ralph Sinkus

 16:15 Measuring Liver Function-Technical Aspects Steven Sourbron1 1Leeds Imaging Biomarkers Group, University of Leeds, United Kingdom This talk will provide a broad introduction of MRI methods to measure the function of liver parenchyma, with more in-depth treatment of Dynamic Gadoxetate-Enhanced MRI for the quantification of hepatocellular transporter function. We will also cover some basic facts about the liver, review competing non-MRI techniques for assessing liver function, and present examples of applications in basic science, drug development and clinical practice.

 237 16:45 Clinical Assessment of Nonalcoholic Steatohepatitis (NASH) with Multi-parametric MRI Jiahui Li1, Alina Allen2, Yi Sui1, Dan Rettmann 3, Ann Shimakawa4, Glenn Slavin5, Kevin J. Glaser1, Sudhakar K. Venkatesh1, Taofic Mounajjed6, Vijay Shah7, Richard L. Ehman1, and Meng Yin1 1Radiology, Mayo Clinic, Rochester, MN, United States, 2Gastroenterology, Mayo Clinic, Rochester, MN, United States, 3GE Healthcare, Waukesha, WI, United States, 4GE Healthcare, Menlo Park, CA, United States, 5GE Healthcare, Silver Spring, MD, United States, 6Anatomic Pathology, Mayo Clinic, Rochester, MN, United States, 7Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, United States In 27 clinical patients, we performed multi-parametric hepatic MRI, including proton density fat fraction with R2* correction, MR Elastography (MRE), and T1 mapping to characterize nonalcoholic steatohepatitis (NASH). Fat fraction and multiple MRE-assessed mechanical parameters successfully diagnosed NASH (p<0.05 for all). Diagnostic abilities of all parameters were evaluated based on steatosis, inflammation and ballooning scores respectively. Spearman correlations were used to analyze the correlations between imaging parameters. We found that T1 relaxation time had a significantly positive correlation (ρ=0.72, p=0.0005) with fat fraction.  In summary, multi-parametric MRI is a potential imaging surrogate for diagnosing NASH.

 238 16:57 Implementation of T1 Mapping in Routine Clinical MR Liver Exam For The Detection of Hepatic Fibrosis and Portal Hypertension in Hepatitis C Patients Ahmed Hamimi1, Ronald Ouwerkerk1, Theo Heller2, Elliot Levy3, Jatin Raj Matta1, Khaled Abd-elmoniem1, and Ahmed M Gharib1 1Biomedical and Metabolic Imaging Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD, United States, 2Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD, United States, 3Interventional Radiology, Clinical Center, NIH, Bethesda, MD, United States Application of two short single breath hold T1 mapping shMOLLI technique (before and after Gadolinium injection) to a routine clinical MRI liver exam can detect both severe fibrosis and portal hypertension in Hepatitis C. The technique was prospectively validated in 29 patients with reference standard clinical methods including liver biopsy and direct portal venous pressure measurements. Utilizing this method would allow for a comprehensive anatomic and functional MRI study in a single session without substantial prolongation of scan time, thereby, allow non-invasive monitoring of therapy and/or progression of disease.

 17:09 Prognosis & Prediction for Liver Tumors Ihab Kamel1 1Johns Hopkins Hospital, United States

 239 17:39 Preoperative Remnant Liver Function Evaluation using a Clinical-Available Gd-EOB-DTPA-Enhanced MR Imaging Protocol in HCC Patients Yajie Wang1, Lin Zhang2, Jia Ning1, Xinjing Zhang3, Xuedong Wang3, Shizhong Yang3, Jiahong Dong3, and Huijun Chen1 1Center for Biomedical Imaging Research, School of Medicine, Tsinghua University, Beijing, China, 2Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing, China, 3Beijing Tsinghua Changgung Hospital, School of Medicine, Tsinghua University, Beijing, China Accurate evaluating of remnant liver function preoperatively is important for surgery planning and reducing posthepatectomy liver failure (PHLF) rate in hepatocellular carcinoma (HCC) patients. In this study, an accurate remnant liver function evaluation method was proposed using a clinical-available MR imaging protocol. The remnant liver function measured by the proposed method showed significant difference between the patients with and without PHLF. More importantly, ROC analysis showed the proposed method has a larger AUC than remnant liver volume and ICG based parameters in predicting PHLF.

 240 17:51 MRI texture features as predictors of histopathologic and genomic characteristics of hepatocellular carcinoma. Stefanie Hectors1, Sara Lewis1,2, Cecilia Besa1, Michael King2, Juan Putra3, Stephen Ward3, Takaaki Higashi4, Swan Thung3, Yujin Hoshida4, and Bachir Taouli1,2 1Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 2Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 3Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 4Department of Medicine/Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, NY, United States The goal of this study was to assess the diagnostic value of texture features measured with MRI compared to qualitative imaging traits for the prediction of histopathologic and genomic characteristics of hepatocellular carcinoma (HCC) lesions. Texture features exhibited additional, complementary correlations with histopathology and genomics compared to qualitative imaging traits, including association with microvascular invasion and expression of immunotherapy target CTLA4. These promising results warrant further investigation of texture features as predictors of histopathologic and genomics measurements in HCC.

 241 18:03 Presence of non-hypervacular hypointense nodule on hepatobiliary phase of gadoxetic acid enhanced MR: Risk of tumor recurrence after curative treatment for small single nodular HCC and guidance for selection of treatment option Dong Ho Lee1 and Jeong Min Lee1 1Radiology, Seoul National University Hospital, Seoul, Republic of Korea Presence of non-hypervascular hypointense nodule on hepatobiliary phase of gadoxetic acid enhanced liver MR can stratify the risk of tumor recurrence after curative treatment for small single nodular HCC equal to or less than 3cm.

 18:15 Adjournment & Meet the Teachers

Oral

### Frontiers of Image Reconstruction

 N03 Monday 16:15 - 18:15 Moderators: Julia Velikina & Sajan Goud Lingala

 242 16:15 3D-Patch-Based Low-Rank Reconstruction (PROST) for Highly-Accelerated CMRA Acquisition Aurelien Bustin1, Gastao Cruz1, Giulia Ginami1, Teresa Correia1, Imran Rashid1, Radhouene Neji1,2, Rene Botnar1, and Claudia Prieto1 1School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom, 2MR Research Collaborations, Siemens Healthcare Limited, Frimley, United Kingdom Free-breathing coronary MR angiography (CMRA) has shown great potential to visualize coronary stenosis. Three-dimensional (3D) CMRA, however, remains time consuming because a large amount of data is needed to accurately visualize all major coronary arteries. Scan acceleration using compressed sensing (CS) reconstruction has successfully been applied to coronary artery imaging. For high acceleration factors, however, CS-based techniques suffer from residual aliasing artifacts which compromise the diagnostic value of the reconstructed image. We propose a new 3D-patch-based reconstruction that exploits the complex 3D anatomy of the coronary arteries in an effective low-rank framework, which combined with 100% respiratory efficiency enables high-quality isotropic Cartesian CMRA images in ~3 mins.

 243 16:27 Kernel low-rank regularization: an efficient approach for recovering dynamic images on a manifold Sunrita Poddar1, Yasir Mohsin1, Bijoy Thattaliyath1, Diedra Ansah1, and Mathews Jacob1 1University of Iowa, Iowa City, IA, United States The main focus of this abstract is to introduce an efficient algorithm to recover a free breathing and ungated cardiac MR image series from highly undersampled measurements. The main contributions are (i) a kernel low-rank algorithm to estimate the manifold structure (Laplacian) from noisy navigator signals, (ii) a fast algorithm that uses the Laplacian basis functions to recover the data from highly undersampled measurements. The utility of the algorithm is demonstrated on radial acquisitions from patients with congenital heart disease; the results show that the framework is a promising alternative to self-gating methods.

 244 16:39 Gradient-Controlled Local Larmor Adjustment (GC-LOLA) for CAIPIRINHA-Accelerated bSSFP Imaging with Improved Banding Behavior Daniel Stäb1,2 and Peter Speier3 1The Centre for Advanced Imaging, The University of Queensland, Brisbane, Australia, 2Department for Diagnostic and Interventional Radiology, University of Würzburg, Würzburg, Germany, 3Siemens Healthcare, Erlangen, Germany The simultaneous multi-slice (SMS) imaging technique CAIPIRINHA has proven to be highly efficient for extending the slice coverage in 2D imaging. When accelerating balanced steady-state free-precession (bSSFP) sequences with SMS-CAIPIRINHA, modulating k-space by means of slice-specific RF phase cycles leads to undesired slice-specific shifts of the bSSFP pass-band structure. Gradient-controlled local Larmor adjustment (GC-LOLA) removes this drawback. By means of slice gradient unbalancing, the Larmor frequency is made slice position dependent, which allows compensating for the pass-band shifts and stabilizes CAIPIRINHA-accelerated bSSFP imaging with respect to B0 field inhomogeneity.

 245 16:51 Ultrafast Speech Imaging at High Spatial Resolution using Model-Consistency Condition Reconstruction with Progressive Temporal Basis Learning Julia Velikina1, Andrew Alexander1, Joseph Salmons1, Eric Raimy1, Thomas Purnell1, Steven Kecskemeti1, and Alexey Samsonov1 1University of Wisconsin - Madison, Madison, WI, United States Dynamic MRI holds high potential for real-time imaging of upper airway, which can provide insights into questions of speech science and also have important clinical applications.  However, speech imaging places increased demands on spatial and temporal resolution, necessitating image reconstruction from severely undersampled data.  Previously reported methods use low-rank constraints with spiral navigators to enable temporal basis estimation, otherwise infeasible with standard learning methods.  We propose an alternative solution based on a novel concept of progressive learning, which does not require separate specialized pulse sequences for navigator acquisitions, while providing high 7.4 ms temporal and 1.25x1.25x8 mm spatial resolution.

 246 17:03 3D Dynamic Hyperpolarized-13C Parallel MRI of Human Brain using SVD Low-Rank Matrix Completion Hsin-Yu Chen1, Ilwoo Park2, Peng Cao1, Robert A. Bok1, Jeremy W. Gordon1, Peter J. Shin1, James B. Slater1, Mark van Criekinge1, Lucas Carvajal1, Adam Autry1, John Kurhanewicz1, Peder E.Z. Larson1, and Daniel B. Vigneron1 1Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States, 2Department of Radiology, Chonnam National University Medical School and Hospital, Gwangju, Republic of Korea The goal of this feasibility study was to develop and apply new 3D dynamic hyperpolarized 13C combined parallel imaging + compressed sensing MRI methods for human brain studies. The new framework utilizing multichannel coils and low-rank matrix completion reconstruction provided greatly improved coverage as compared to prior 2D acquisitions. Whole-brain coverage was achieved, while maintaining the image quality in terms of spatial distribution, temporal dynamics and quantitative accuracy of the 13C biomarkers. Animal studies and simulations also showed that the pMRI+CS framework provided improved performance over CS alone, and was able better to recover low-SNR peaks.

 247 17:15 Reconstruction of Arrhythmic Cardiac Cycles in Patients with Atrial Fibrillation Teodora Chitiboi1, Li Feng1, Rebecca Ramb2, Ricardo Otazo1, and Leon Axel1 1New York University School of Medicine, New York, NY, United States, 2Siemens Healthineers, Erlangen, Germany Arrhythmia is often a significant challenge to acquiring diagnostic quality cardiac MRI. While discarding atypical cardiac cycles can exclude short-lived arrhythmic events, such as premature ventricular contractions (PVCs), this fails for atrial fibrillation (Afib), where subjects have an irregular cardiac cycle pattern. Harnessing the potential of the XD-GRASP MRI technique to reconstruct continuously acquired data with cardiac and respiratory phase as extra dimensions, we propose to additionally classify cardiac cycles for Afib patients according to their preload state, and simultaneously reconstruct the different types of arrhythmic cycles in a five-dimensional image space.

 248 17:27 Highly Undersampled Kooshball Reconstruction with Low-rank Modeling and Sparsity Constraints for High-resolution T1 Mapping Haikun Qi1, Huiyu Qiao1, Aiqi Sun1, Shuo Chen1, Xihai Zhao1, Rui Li1, Chun Yuan1,2, and Huijun Chen1 1Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China, 2Department of Radiology, University of Washington, Seattle, WA, United States Highly undersampled 3D radial is very useful for 3D imaging acceleration, and compressed sensing and low-rank can be used for reconstruction of the undersampled kooshball data. In this study, we propose a novel reconstruction method for fast 3D T1 mapping of carotid artery using 3D radial sampling. The reconstruction method is based on low-rank modeling with parallel imaging and sparsity constraints, and is potential to improve the accuracy and precision of T1 estimation. The aim of this study is to evaluate the effectiveness of the proposed method using phantom and in vivo imaging experiments on volunteers and carotid atherosclerosis patients.

 249 17:39 Assessing MR image reconstruction quality using the Fourier Radial Error Spectrum plot Tae Hyung Kim1 and Justin P. Haldar1 1Electrical Engineering, University of Southern California, Los Angeles, CA, United States This work introduces the Fourier radial error spectrum plot (ESP) as a novel approach to quantifying the quality of reconstructed MR images.  While conventional error metrics such as normalized root mean squared error (NRMSE) or structural similarity (SSIM) are widely used, they are simple scalar-measures that only provide one-dimensional insight into image quality.  In contrast, ESP describes reconstruction quality with a spectrum that provides a quantitative evaluation of image quality at every spatial resolution scale.  Our results show that ESP provides more comprehensive information than conventional error metrics, and can guide the design of new and improved image reconstruction approaches.

 250 17:51 Complex Image Extraction in Phased-Array Imaging Peter J Shin1 and Daniel B Vigneron1 1Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States Phased-array coils are used in MRI to improve signal-to-noise ratio (SNR) or to accelerate data acquisition speed through parallel imaging. It is beneficial to have a phased-array imagery reconstruction method that extracts the complex magnetization information from the multichannel data. In this work, we adopt the fusion frame theory to estimate the magnitude of the underlying magnetization and further employ the matched-filter method to estimate the magnetization phase, thereby reconstructing a complex image that does not have coil sensitivity weightings.

 251 18:03 Rapid self-tuning compressed-sensing MRI using projection onto epigraph sets Mohammad Shahdloo1,2, Efe Ilıcak1,2, Mohammad Tofighi3, Emine U. Sarıtaş1,2,4, A. Enis Cetin1,5, and Tolga Çukur1,2,4 1Electrical and Electronics Engineering Department, Bilkent University, Ankara, Turkey, 2National Magnetic Resonance Research Center (UMRAM), Bilkent University, Ankara, Turkey, 3Department of Electrical Engineering, Pennsylvania State University, State College, PA, United States, 4Neuroscience Program, Bilkent University, Ankara, Turkey, 5Electrical & Computer Engineering Department, University of Illinois at Chicago, Chicago, IL, United States Successful compressed-sensing reconstruction often involves tuning one or more regularization weights. However, tuning the regularization weights is a subject-specific, task-dependent and non-trivial task. Recent studies have proposed to determine the weights by minimizing the statistical risk of removing significant coefficients using line searches across a range of parameters. However, the line-search procedures lead to prolonged reconstruction times. Here, we propose a new self-tuning approach generalized for multi-coil, multi-acquisition CS reconstructions that leverage projection onto epigraph sets of  l1 and TV balls. The proposed method yields 7 to 9-fold gain in computational efficiency over conventional methods while enabling further improved image quality.

Oral

### Microstructure: A Stroll in the q-Space

 N04 Monday 16:15 - 18:15 Moderators: Noam Shemesh & Ileana Jelescu

 252 16:15 Breaking the power law scaling of the dMRI signal on the Connectom scanner reveals its sensitivity to axon diameters Jelle Veraart1, Els Fieremans1, Umesh Rudrapatna2, Derek K Jones2, and Dmitry S Novikov1 1Center for Biomedical Imaging, NYU School of Medicine, New York, NY, United States, 2CUBRIC, Cardiff University, Cardiff, United Kingdom We demonstrate that in vivo diffusion MRI becomes sensitive to intra-axonal properties such as the inner axon diameters, when diffusion weightings in the range $b\sim7,000-25000\,\mathrm{s/mm^2}$ are achieved on the Human Connectom scanner (using gradients of 300mT/m). By analyzing the diffusion-weighted signal in the human white matter as a function of $b$, we observe significant deviations from the $b^{-1/2}$ scaling associated with the conventional “stick” model of infinitely-narrow axons. Our estimated effective MR diameters, heavily weighted by the tail of the axon diameter distribution, agree well with those calculated from histology histograms available from literature.

 253 16:27 The Dot…wherefore art thou? Search for the isotropic restricted diffusion compartment in the brain with spherical tensor encoding and strong gradients Chantal M.W. Tax1, Filip Szczepankiewicz 2,3, Markus Nilsson2, and Derek K Jones1 1CUBRIC, School of Psychology, Cardiff University, Cardiff, United Kingdom, 2Clinical sciences, Lund, Lund University, Lund, Sweden, 3Random Walk Imaging AB, Lund, Sweden The accuracy of biophysical models requires that all relevant tissue compartments are modelled. The so-called “dot compartment” is a conjectured compartment that represents small cells with apparent diffusivity approaching zero. We establish an upper limit of the “dot-fraction” across the whole brain in vivo, by using ultra-high gradients and optimized gradient waveforms for spherical tensor encoding. We report a notable signal above the noise floor in the cerebellar gray matter even for an extremely high b-value of 15000 s/mm2. For cerebral tissue, the dot-fraction seems negligible, and we consider how exchange may have affected this result.

 254 16:39 Effect of combining linear with spherical tensor encoding on estimating brain microstructural parameters Els Fieremans1, Jelle Veraart1, Benjamin Ades-Aron1, Filip Szczepankiewicz2,3, Markus Nilsson2, and Dmitry S Novikov1 1Radiology, New York University School of Medicine, New York, NY, United States, 2Clinical Sciences, Lund University, Lund, Sweden, 3Random Walk Imaging AB, Lund, Sweden The diffusion MRI signal, as measured with conventional linear tensor encoding (LTE), has been shown to have not enough features to fully model the white matter microstructure. Here we investigate whether adding spherical encoding (STE) to LTE makes microstructural parameter estimation more robust. On signal simulations and in in vivo MRI data, we demonstrate that the intra-axonal diffusivity and axonal water fraction are estimated with higher precision, thereby enabling a 20 minute whole brain protocol to extract brain microstructural parameters without imposing constraints or priors.

 255 16:51 Unconstrained Estimation of Microstructure by the Combination of Single- and Double-planar diffusion encoding Marco Reisert1, Valerij G. Kiselev1, and Bibek Dhital1 1University Freiburg, Faculty of Medicine, Freiburg, Germany Modeling of white matter microstructure using standard diffusion MRI protocols is a poor-conditioned problem. With standard measurements  there is a global degeneracy: There are two significantly different microstructural parameter sets explaining experimental data equally well. In this work we use an additional planar double diffusion encoding to resolve the degeneracy, and extend a Bayesian estimation framework to a combination of linear and planar diffusion encoding. This enables us to produce reliable estimates without applying any constraints to the microstructural diffusion model.

 256 17:03 A Novel Method for Fast and Efficient Measurement of Diffusion Tensor Size and Shape Distributions Grant Yang1,2 and Jennifer McNab2 1Electrical Engineering, Stanford University, Stanford, CA, United States, 2Radiology, Stanford University, Stanford, CA, United States We demonstrate through simulations and empirical data that it is possible to simultaneously estimate the variance of the voxel-wise diffusion tensor shape and size distributions using efficient isotropic and linear diffusion encodings on a whole-body clinical MRI scanner with whole-brain coverage at 3mm isotropic resolution in under 2 minutes.

 257 17:15 The "Magic DIAMOND" method: probing brain microstructure by combining b-tensor encoding and advanced diffusion compartment imaging Alexis Reymbaut1, Benoit Scherrer2, Guillaume Gilbert3, Filip Szczepankiewicz4,5, Markus Nilsson4, and Maxime Descoteaux1 1Université de Sherbrooke, Sherbrooke, QC, Canada, 2Dept. of Radiology, Boston Children’s Hospital, Boston, MA, United States, 3MR Clinical Science, Philips Healthcare Canada, Markham, ON, Canada, 4Department of Clinical Sciences, Lund, Lund University, Lund, Sweden, 5Random Walk Imaging AB, Lund, Sweden Via q-trajectory encoding, b-tensors enable the disentanglement of isotropic and anisotropic diffusion components. Relevant metrics are usually extracted from data acquired with a combination of linear and spherical b-tensors with 1D parametric distributions of diffusivities. Independently, the DIAMOND model proposed an analytic result for a 6D parametric compartmental tensor distribution based on linearly acquired data. In this work, we extend DIAMOND’s analyticity to axisymmetric acquisitions. Evaluating this "Magic DIAMOND" approach on in vivo data, we show that it can tease apart isotropic diffusion and diffusivity compartments of crossing fascicles, hereby integrating specific compartments with intra-compartment diffusional variance.

 258 17:27 On the magnetic field and echo time dependence of the pseudo-diffusion coefficient Andreas Julian Riexinger1, Andreas Wetscherek2, Jan Martin1, Tristan Anselm Kuder3, Armin Nagel1, Michael Uder1, Bernhard Hensel4, Lars Müller3,5, and Frederik Bernd Laun1 1Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany, 2Joint Department of Physics, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, United Kingdom, 3Department Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, 4Center for Medical Physics and Engineering, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany, 5CUBRIC, School of Psychology, Cardiff University, Cardiff, United Kingdom It has been reported that a strong echo time dependence of the perfusion fraction f exists in liver and pancreas. The purpose of this work is to investigate whether a similar dependence exists for the pseudo-diffusion coefficient D*. Thereto, the livers of six healthy volunteers were examined at two echo times (TE = 40/80 ms) at two field strengths. In contrast to f, D* shows almost no echo time dependence in the healthy liver and the observed field strength dependence was smaller than the fit uncertainty.

 259 17:39 Cell specific anisotropy with double diffusion encoding spectroscopy in the human brain at 7T Henrik Lundell1, Andrew Webb2, and Itamar Ronen2 1Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark, 2C. J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, Netherlands The measurement of intracellular metabolite mobility with diffusion weighted spectroscopy (DWS) provides a cell-specific probe for microstructure. Measurements in animals and humans with conventional one dimensional diffusion encoding and model-guided analysis suggest that the main component of the intracellular space of both neurons and astrocytes comprises mainly  anisotropic fibrous geometries. In this study we performed double diffusion encoded spectroscopy (DDES) in the human brain as a direct probe of anisotropic intracellular diffusion. As expected, our results support a main fibrous component but the results also suggest a more complex geometry of astrocytes that could include isotropic compartments.

 260 17:51 Validity Regimes of the Spherical Mean Technique Rafael Neto Henriques1 and Noam Shemesh1 1Champalimaud Research, Champalimaud Centre for the Unknown, Lisbon, Portugal The mean spherical technique (SMT) has been proposed as an attempt to disentangle microscopic diffusion properties from the mesoscopic tissue organization. However, it remains unclear under which conditions exactly the technique could still fruitfully deliver its metrics. In this study, SMT’s microscopic fractional anisotropy estimates (μFA) are investigated using synthetic and high-quality diffusion data. We find that any compartmental heterogeneity can crucially impact the µFA extracted from SMT. In addition, the b-value ranges where SMT delivers accurate information is specific to the microstructure itself. Our work suggests that SMT-driven µFA should be examined with care.

 261 18:03 Non-Invasive Determination of Sodium Pump Activity In Vivo with DWI Charles S. Springer1, Gregory J. Wilson2, Brendan Moloney1, Thomas M. Barbara1, Xin Li1, William D. Rooney1, and Jeffrey H. Maki3 1Advanced Imaging Research Center, Oregon Health & Science University, Portland, OR, United States, 2Radiology, University of Washington, Seattle, WA, United States, 3Radiology, University of Colorado Denver, Aurora, CO, United States Using a very simple model, Monte Carlo random walk simulated DWI b-space decays exhibit sensitivity to parameters measuring membrane Na+,K+-ATPase activity, cell density, and voxel average cell volume.  Furthermore, the simulation matching the literature experimental in vivo human cerebral cortex b‑space decay has model parameters in near absolute agreement with the most pertinent literature values.  The model parameters are: kio = 2 s-1, ρ = 80,400 cells/μL, and V = 9.2 pL.  In addition, the ADC of this simulation agrees with published results.

Oral

### Parameter Quantification

 S03 Monday 16:15 - 18:15 Moderators: Tobias Kober & Jürgen Reichenbach

 262 16:15 Simultaneous B1 and T1 Mapping Using Spiral Variable-Flip-Angle Acquisitions for Whole-Brain Coverage in Less Than One Minute Rahel Heule1,2,3, Josef Pfeuffer4, Craig H. Meyer5, and Oliver Bieri1,2 1Division of Radiological Physics, Department of Radiology, University of Basel Hospital, Basel, Switzerland, 2Department of Biomedical Engineering, University of Basel, Basel, Switzerland, 3High Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Tübingen, Germany, 4Siemens Healthcare GmbH, Application Development, Erlangen, Germany, 5Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, United States Rapid variable-flip-angle T1 mapping techniques are frequently applied in clinical settings, but their accuracy is often impaired by incomplete spoiling or flip angle miscalibrations. To eliminate these two error sources simultaneously, a combined B1 and T1 mapping method is proposed based on spiral 2D multislice spoiled gradient echo imaging with high spoiling efficiency. The transition to steady state is minimized by an optimized single preparation pulse. A single-shot spiral readout during the preparation module enables ultrafast B1 mapping and as a result reproducible bias-free T1 mapping with whole-brain coverage at clinically relevant resolution in less than one minute.

 263 16:27 Rapid simultaneous acquisition of QSM and MTV Fang Frank Yu1, Susie Yi Huang1, Tanguy Duval2, Julien Cohen-Adad2, and Berkin Bilgic3 1Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States, 2Institute of Biomedical Engineering, Ecole Polytechnique de Montreal, Montreal, QC, Canada, 3Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States Quantitative susceptibility mapping (QSM) and macromolecular tissue volume (MTV) represent quantitative methods that improve characterization of neurodegenerative diseases. MTV involves acquisition of 3D-Gradient Echo (GRE) at multiple flip angles with long TR and short TE. High-quality QSM requires 3D-GRE at multiple head orientations with long TE. We exploit (i) unused time due to long TR in MTV to collect additional late echoes that allow QSM processing, (ii) acquire each of the multiple flip angles at a different head orientation. These permit simultaneous acquisition of QSM and MTV, whereby two maps are obtained at the scan time of a single contrast.

 264 16:39 Myelin water atlas: a template for myelin distribution in the brain Hanwen Liu1,2, Cristina Rubino3, Mike Jarrett4,5, Emil Ljungberg6, Irene Vavasour7, Shannon Kolind1,7,8, Erin Leigh MacMillan9,10,11, Tony Traboulsee12, Donna Lang7, Alex Rauscher4,7, David Li7, Alex MacKay1,7, Lara Boyd13, John Kramer2,14, and Cornelia Laule2,7 1Physics, University of British Columbia, Vancouver, BC, Canada, 2International Collaboration on Repair Discoveries, Vancouver, BC, Canada, 3Rehabilitation Sciences, University of British Columbia, Vancouver, BC, Canada, 4Pediatrics, University of British Columbia, Vancouver, BC, Canada, 5UBC MRI Research Centre, University of British Columbia, Vancouver, ON, Canada, 6IoPPN, King's College London, London, United Kingdom, 7Radiology, University of British Columbia, Vancouver, BC, Canada, 8Medicine, University of British Columbia, Vancouver, BC, Canada, 9MR Clinical Science, Philips Healthcare Canada, Markham, ON, Canada, 10UBC MRI Research Centre, University of British Columbia, Vancouver, BC, Canada, 11ImageTech Lab, Simon Fraser University, Surrey, BC, Canada, 12University of British Columbia, Vancouver, BC, Canada, 13Physical Therapy, University of British Columbia, Vancouver, BC, Canada, 14Kinesiology, University of British Columbia, Vancouver, BC, Canada In-vivo information about myelin content in the brain is desirable for studying brain diseases and injuries. Normative information is key for determining what is abnormal when assessing neurological conditions that affect myelin. We used myelin water imaging to create a template specific to myelin, the myelin water atlas, for healthy brains. The resulting atlas shows strong agreement with well-known anatomical features that have demonstrated that different brain regions have distinct amounts of myelin. Our work shows one of the potential applications of using the myelin water atlas as a reference to visualize demyelination in the brain of individual subjects.

 265 16:51 Multi-atlas tool for automated magnetic susceptibility quantification in brain nuclei Andreia Vasconcellos Faria1, Lin Chen2, Kwame Kutten3, Can Ceritoglu3, Ningdong Kang1, Li Pan4, Ye Qiao1, Michael Miller3, Susumu Mori1, David Yousem1, Peter C van Zijl2, and Xu Li2 1Radiology, Johns Hopkins University, Baltimore, MD, United States, 2Kennedy Krieger Institute, Johns Hopkins University, Baltimore, MD, United States, 3Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States, 4Siemens Healthineers, Baltimore, MD, United States Quantitative magnetic susceptibility offers a non-invasive measure of important brain tissue molecules, such as iron complexes and myelin, potentially providing significant information about normal and pathological conditions during aging. We developed an automated process to quantify tissue susceptibility in a biologically meaningful set of structures, thereby generating universal and sharable quantitative susceptibility measures. Our susceptibility-based multi-atlas outperformed the single atlas and the T1-weighted multi-atlases. Our tool and normalization algorithm offered consistent measures of magnetic susceptibility over different image protocols and platforms. Automatic and reliable quantitative susceptibility mapping measures will facilitate individual analyses and studies on aging and neurodegeneration.

 266 17:03 High-resolution in-vivo multi-parametric MRI using MR-STAT with a highly parallelized, limited-memory reconstruction algorithm Oscar van der Heide1, Alessandro Sbrizzi1, Peter Luijten1, and Cornelis van den Berg1 1Center for Image Sciences, UMC Utrecht, Utrecht University, Utrecht, Netherlands MR-STAT is a framework for obtaining multiple quantitative parameter maps from a very short scan. The parameter maps are obtained by fitting a Bloch-based signal model directly to the time domain data. No Fourier transform is needed.  In this work we demonstrate that MR-STAT can obtain excellent high-resolution in-vivo quantitative maps using very short Cartesian acquisitions standardly available on clinical MR systems. The solution of the large-scale reconstruction problem is made possible by a highly parallelized, limited-memory algorithm.

 267 17:15 Increased Measurement Efficiency for Fat Quantification Using a Mixed Polarity Bipolar Acquisition Scheme Ruitian Song1, Nathan S. Artz1, Ralf B. Loeffler1, and Claudia M. Hillenbrand1 1St Jude Children's Research Hospital, Memphis, TN, United States A new mixed polarity bipolar GRE sequence is proposed for fat quantification by mixing positive and negative readout polarity in one echo acquisition. Accurate fat fraction maps can be obtained using the proposed method with up to 50% scan time savings compared to a dual shot unipolar GRE method.

 268 17:27 Comparison of 3D spoiled-gradient multiple echo with STEAM for proton density fat fraction and fatty acid composition estimation Angéline Nemeth1, Hélène Ratiney1, Benjamin Leporq1, Kévin Seyssel2, Bérénice Segrestin3, Pierre-Jean Valette4, Martine Laville3, and Olivier Beuf1 1Univ. Lyon, INSA‐Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, F69621, VILLEURBANNE, France, Lyon, France, 2Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Lausanne, Switzerland, 3Centre de Recherche en Nutrition Humaine Rhône-Alpes (CRNH-RA), Centre Hospitalier Lyon Sud, Pierre-Bénite, Lyon, France, 4Hospices Civils de Lyon, Département d'imagerie digestive, CHU Edouard Herriot, Lyon, Lyon, France A total of 39 volunteers underwent an imaging and spectroscopy protocol on a 3T Ingenia Philips system with an axial 3D spoiled-gradient multiple echo sequence on abdominal region and a set of three STEAM sequences acquired on subcutaneous adipose tissue, visceral adipose tissue and liver. The quantification of Proton density fat fraction (PDFF), proportion of saturated (SFA), monounsaturated (MUFA) or polyunsaturated (PUFA) fatty acids from both MRI and MRS methods were compared. Good correlation with a little bias was found for the liver PDFF. Values of PUFA, MUFA and SFA from both techniques were poorly correlated.

 269 17:39 Quantitative Measurements of Deep Medullary Vein Caliber and Oxygenation Level Using MRI Phase and Complex Images Xiaopeng Zong1 and Weili Lin1 1Biomedical Research Imaging Center and Department of Radiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States Collagenosis-induced narrowing of deep medullary vein (DMV) caliber has been implicated as one of the main causes of small vessel disease.  However, a non-invasive imaging method for monitoring the DMV narrowing is still lacking.  We present an MRI method for non-invasive measurement of DMV caliber and oxygenation level base on MRI phase and complex images acquired using a double echo gradient echo sequence at 7 T. The measured DMV caliber distribution agreed well with earlier report.  Our approach can serve as an invaluable tool  for studying the role of venous lumen narrowing in the pathogenesis of small vessel disease.

 270 17:51 Silent T1-Mapping Using the Variable Flip Angle Method with Zero Echo Time Emil Ljungberg1,2, Ana Beatriz Solana Sanchez2, Tobias C Wood1, Shannon Kolind3,4,5, Florian Wiesinger2, and Gareth J Barker1 1Neuroimaging, King's College London, London, United Kingdom, 2GE Healthcare, Munich, Germany, 3Medicine, University of British Columbia, Vancouver, BC, Canada, 4Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada, 5Radiology, University of British Columbia, Vancouver, BC, Canada In this work we present a silent whole brain T1-mapping technique with zero echo time using a variable flip angle (VFA) scheme with a 3D radial sequence (RUFIS). The technique is compared to a conventional Cartesian gradient-echo based sequence (DESPOT1-HIFI) in a quantitative T1 phantom as well as in vivo in a single subject. Phantom measurements showed good agreement between techniques with average difference of 28 ms. In vivo T1 maps showed good correspondence between RUFIS and DESPOT1-HIFI.

 271 18:03 Explicit mathematical expression for the Cramér-Rao lower bound for experimental design and parameter estimation in parallel imaging Mustapha Bouhrara1 and Richard G. Spencer1 1National Institutes of Health, Baltimore, MD, United States The Cramér-Rao lower bound (CRLB) is widely used in the design of magnetic resonance (MR) experiments for parameter estimation. Previous work has considered only Gaussian or Rician noise distributions in this calculation.  However, the noise distribution for multiple-coil acquisitions, such as in parallel imaging, obeys the noncentral χ-distribution under many circumstances. Here, we present the general mathematical expression for the CRLB calculation for parameter estimation from multiple-coil acquisitions. Our results indicate that the CRLB calculation must account for the noncentral χ-distribution of noise in multi-coil acquisitions, especially in the low-to-moderate signal-to-noise ratio (SNR) regime.

Oral

### Hyperpolarisation: Probe Development & Clinical Application

 S04 Monday 16:15 - 18:15 Moderators: Kerstin Timm & Jan Henrik Ardenkjær-Larsen

 272 16:15 In vivo Imaging of Hyperpolarized Silicon-29 Nanoparticles Grzegorz Kwiatkowski1, Jonas Steinhauser1, Patrick Wespi1, Matthias Ernst2, and Sebastian Kozerke1 1Institute for Biomedical Engineering, ETH & University of Zurich, Zurich, Switzerland, 2Labolatory of Physical Chemistry, ETH Zurich, Zurich, Switzerland Hyperpolarized silicon particles exhibit very long T1 relaxation at room temperature, making them favourable as novel imaging MR probes. It has recently been shown that silicon particles in the nanometer size range can be efficiently polarized and image even after 4 hours upon transfer of the sample to the imaging system. The objective of the present work was to demonstrate the imaging capability of surface functionalized hyperpolarized nanometer size silicon particles in an experimental in-vivo setting.

 273 16:27 An in vivo metabolic imaging study of myopathy in transgenic mice using C-13 hyperpolarized pyruvate generated by ParaHydrogen Francesca Reineri1, Eleonora Cavallari1, Carla Carrera1, and Silvio Aime1 1Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy Hyperpolarized [1-13C]pyruvate has been widely exploited for the in vivo investigation of metabolic processes under normal and diseased conditions. The possibility to obtain it using the cost effective and fast PHIP (ParaHydrogen Induced Polarization) method would allow a widespread application of this powerful diagnostic tool to pre-clinical research and would pave the way to future clinical translation. Here we show the first in vivo studies carried out on genetically modified mice using [1-13C]pyruvate obtained by means of the PHIP-SAH (PHIP-Side Arm Hydrogenation) method. The results obtained from PHIP-SAH hyperpolarized pyruvate are consistent with the pathologic state of the heart tissue.

 274 16:39 Hyperpolarized sodium [1-13C]glycerate as a probe for assessing glycolysis in vivo Jae Mo Park1,2,3, Marvin Wu4, Thomas Hever1, Xiaodong Wen1, Daniel M Spielman5, and Kelvin Billingsley6 1Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States, 2Radiology, University of Texas Southwestern Medical Center, Dallas, TX, United States, 3Electrical and Computer Engineering, University of Texas at Dallas, Richardson, TX, United States, 4Chemistry and Biochemistry, San Francisco State University, San Francisco, CA, United States, 5Stanford University, Stanford, CA, United States, 6Chemistry and Biochemistry, California State University, Fullerton, Fullerton, CA, United States We describe the synthesis, development and in vivo application of sodium [1-13C]glycerate as a novel probe for evaluating glycolysis using hyperpolarized 13C MRS. [13C]glycerate displayed a high level of polarization and long spin-lattice relaxation time. In vivo spectroscopic studies with hyperpolarized [13C]glycerate in rat liver furnished metabolic products, pyruvate and lactate, originating from glycolysis. The levels of production and relative intensities of these metabolites were directly correlated with the induced glycolytic state (fasted versus fed). This work establishes hyperpolarized [13C]glycerate as a novel agent for clinically relevant 13C MRS studies of energy metabolism and further provides opportunities for evaluating intracellular redox states in biochemical investigations.

 275 16:51 Overestimation of cardiac lactate production due to liver metabolism of hyperpolarized [1-13C] pyruvate Patrick Wespi1, Jonas Steinhauser1, Grzegorz Kwiatkowski 1, and Sebastian Kozerke1 1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland Spectroscopy is widely used in hyperpolarized metabolic experiments due to its simplicity and robustness. In this work, it is shown that with spectroscopic acquisition in rat hearts, the cardiac lactate production is overestimated due to liver metabolism of [1-13] pyruvate. It is demonstrated that this overestimation can be addressed using spatially resolved data.

 276 17:03 Hyperpolarized 13C Metabolic Imaging of Human Hypertrophic Cardiomyopathy Angus Z. Lau1,2, Albert P. Chen3, Justin Y.C. Lau1,2, Benjamin J. Geraghty1,2, William J. Perks4, Idan Roifman5, Graham A. Wright1,2,5, Kim A. Connelly6, and Charles H. Cunningham1,2 1Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON, Canada, 2Medical Biophysics, University of Toronto, Toronto, ON, Canada, 3GE Healthcare, Toronto, ON, Canada, 4Pharmacy, Sunnybrook Health Sciences Centre, Toronto, ON, Canada, 5Schulich Heart Program, Sunnybrook Health Sciences Centre, Toronto, ON, Canada, 6Cardiology, St. Michael's Hospital, Toronto, ON, Canada The feasibility of using hyperpolarized 13C to interrogate in vivo human metabolism in the healthy heart has recently been demonstrated. In this abstract we demonstrate the feasibility of using hyperpolarized 13C imaging to detect metabolic alterations in human hypertrophic cardiomyopathy. Results show significantly elevated 13C-bicarbonate-to-pyruvate ratio near the apex of the heart, corresponding to the known location of disease. The 13C-bicarbonate images also show a different spatial distribution from those observed in healthy volunteers. These results show good prospects for imaging the altered cardiac energetics in the diseased heart using this technology.

 277 17:15 Imaging the healthy human brain with hyperpolarized [1-13C] pyruvate James T. Grist1, Mary A. McLean2, Surrin S. Deen1, Frank Riemer1, Charlotte J. Daniels1, Andrew B. Gill1, Fulvio Zaccagna1, Rolf F. Schulte3, Sarah F. Hilborne1, Jackie P. Mason1, James W. McKay1, Arnaud Comment4, Anita Chhabra5, Vicky Fernandes5, Hannah Loveday5, Marie-Christine Laurent1, Ilse Patterson6, Ronnie Hernandez6, Rhys A. Slough6, Tomasz Matys1, Ian B. Wilkinson7, Bristi Basu8, Claire Trumper9, Damian J. Tyler9, David J. Lomas1, Martin J. Graves1, Alasdair J. Coles10, Kevin Brindle2, and Ferdia A. Gallagher1 1Radiology, University of Cambridge, Cambridge, United Kingdom, 2Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom, 3Global Research, General Electric, Munich, Germany, 4Healthcare, General Electric, Cambridge, United Kingdom, 5Pharmacy, Addenbrooke's Hospital, Cambridge, United Kingdom, 6MRIS, Addenbrooke's Hospital, Cambridge, United Kingdom, 7Medicine, University of Cambridge, Cambridge, United Kingdom, 8Oncology, University of Cambridge, Cambridge, United Kingdom, 9Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom, 10Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom Initial results from imaging the healthy human brain with [1-13C] pyruvate are presented. Labelled lactate and bicarbonate formation are seen, as well as differences in gray and white matter perfusion.

 278 17:27 Hyperpolarized Carbon-13 Metabolic Imaging of Pediatric Patients with Brain Tumors: Initial Experience Ilwoo Park1, Adam Autry2, Yiran Chen2, Jeremy Gordon2, Lucas Carvajal2, Hsin-Yu Chen2, Robert Bok2, Mark Van Criekinge2, James Slater2, Cassie Kline-Nunnally3, Peder Larson2, Daniel Vigneron2, Janine Lupo2, Duan Xu2, and Sabine Mueller4 1Radiology, Chonnam National University College of Medicine, Gwanju, Republic of Korea, 2Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, United States, 3Pediatric Hematology-Oncology, University of California San Francisco, San Francisco, CA, United States, 4Neurology, Neurosurgery and Pediatrics, University of California San Francisco, San Francisco, CA, United States This study applied hyperpolarized 13C metabolic imaging in pediatric populations for the first time to our knowledge. Dynamic 13C data were acquired following injection of hyperpolarized [1-13C]pyruvate in the first 3 pediatric patients with brain tumors as part of an ongoing trial (PNOC011,NCT02947373). No adverse effects were observed for these 3 patients. Pyruvate, lactate and bicarbonate signals with high SNR were detected in the pediatric brain. These preliminary results demonstrated the feasibility of using HP [1-13C]pyruvate for assessing in vivo metabolism from pediatric patients with brain tumors and support ongoing investigation of this technology in pediatric patients.

 279 17:39 Multimodal Characterization of In Vivo Metabolic Activities with Hyperpolarized 13C MRI, 18F-FDG PET, and EPR Imaging in Pancreatic Ductal Adenocarcinoma Tumors Kazutoshi Yamamoto1, Tomohiro Seki1, Shun Kishimoto1, Nallathamby Devasahayam1, Nobu Oshima1, Stephen S Adler1, Elaine Jagoda1, Keita Saito1, Jeffrey R Brender1, Peter L Choyke1, James B Mitchell1, and Murali C Krishna1 1National Cancer Institute, National Institutes of Health, Bethesda, MD, United States Profiling the metabolic and physiologic phenotypes of tumors has become important in treatment planning and response monitoring.  Here, multimodal imaging methods, including hyperpolarized 13C MRI, 18F-FDG PET, and EPRI imaging, were used to profile the metabolic and physiologic features of human pancreatic ductal adenocarcinoma (PDAC) tumors, Hs766t, MiaPaCa-2, and SU.86.86. PDACs have some of the worst prognoses of all cancers.  Experimental results have demonstrated, for the first time, the feasibility and advantages of multimodal metabolic and physiologic assessment of xenograft tumors.  This multimodal imaging approach will complement tumor characterization, lead to better prognostics, and earlier response monitoring in cancer treatment.

 280 17:51 The Rate of Hyperpolarized [1-13C] Pyruvate to [1-13C] Lactate Conversion Distinguishes High-Grade Prostate Cancer from Low-Grade Prostate Cancer and Normal Peripheral Zone Tissue in Patients Natalie Korn1,2, Peder EZ Larson1,2, Hsin-Yu Chen1,2, Jeremy Gordon1, Robert A Bok1, Mark VanCriekinge1, James Slater1, Rahul Aggarwal3, Matthew Cooperberg3, Romelyn Delos Santos1, Justin Delos Santos1, Jeffry Simko4, Susan M Noworolski1,2, Daniel B Vigneron1,2, and John Kurhanewicz1,2 1Radiology and Biomedical Imaging, University of California at San Francisco, San Francisco, CA, United States, 2The Graduate Group in Bioengineering, Universities of California at Berkeley and San Francisco, Berkeley and San Francisco, CA, United States, 3Urology, University of California at San Francisco, San Francisco, CA, United States, 4Pathology, University of California at San Francisco, San Francisco, CA, United States The accurate discrimination of aggressive from indolent prostate cancer at diagnosis remains a pressing clinical need. High spatial and temporal resolution 3D dynamic hyperpolarized 13C MRSI has previously demonstrated the ability to correlate hyperpolarized (HP) [1-13C]pyruvate to [1-13C]lactate conversion, kPL, with cancer grade in murine models.  This initial analysis of patients studies enrolled in a phase II pre-prostatectomy clinical trial demonstrated for the first time that maxmium kPL (kPLmax) is significantly elevated in high-grade prostate cancer versus both normal (p=0.0003) and low-grade disease (p=0.034).

 281 18:03 Detection of D-amino acid oxidase using hyperpolarized molecular probes Alice Radaelli1, Hikari Ananda Infinity Yoshihara1, and Rolf Gruetter1,2 1Laboratory for Functional and Metabolic Imaging (LIFMET), EPFL, Lausanne, Switzerland, 2Center for Biomedical Imaging (CIBM), Lausanne, Switzerland D-amino acid oxidase (DAO) is an enzyme that catalyzes the degradation of D-amino acids in the body. Here, we explored the possibility of detecting D-amino acid oxidase activity by monitoring its metabolism in the rat kidney after a bolus injection of hyperpolarized D-[1-13C]alanine. Our data show that D-alanine is readily converted to lactate only when the DAO enzyme is not inhibited, indicating that the observed metabolism is that of DAO.

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### Myocardial Tissue Characterisation

 S05 Monday 16:15 - 18:15 Moderators: Pierre Croisille & Andrew Scott

 282 16:15 Magnetic susceptibility of hemorrhagic myocardial infarction: correlation with tissue iron and comparison with relaxation time MRI Brianna F. Moon1, Srikant Kamesh Iyer PhD2, Michael P. Solomon1, Anya T. Hall1, Rishabh Kumar3, Elizabeth M. Higbee-Dempsey4, Andrew Tsourkas PhD1, Akito Imai MD5, Keitaro Okamoto MD5, Yoshiaki Saito MD5, Jerry Zsido II5, Joseph H. Gorman III MD5, Robert C. Gorman MD5, Giovanni Ferrari PhD6, and Walter R.T. Witschey PhD2 1Bioengineering, University of Pennsylvania, Philadelphia, PA, United States, 2Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States, 3Biophysics, University of Pennsylvania, Philadelphia, PA, United States, 4Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA, United States, 5Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States, 6Surgery, Columbia University, New York City, NY, United States Hemorrhagic myocardial infarction (MI) is a frequent complication of primary percutaneous coronary intervention and independently associated with impaired LV remodeling, function, and arrhythmias.  We demonstrate that cardiac quantitative susceptibility mapping (QSM) shows increased susceptibility in infarcts compared to remote myocardium and correlates with iron content and infarct pathophysiology.  QSM is a more specific marker of hemorrhagic MI than relaxation time MRI, susceptibility-weighted imaging, and late gadolinium enhanced (LGE) MRI.

 283 16:27 Myocardial T2 mapping using a Black-blood hEart-rate Adaptive T2-prepared bSSFP (BEATS) sequence Chengyan Wang1,2, Jihye Jang1,3, Ahmed Fahmy1,4, Jinkyu Kang1, Beth Goddu1, Sophie Berg1, Jue Zhang2, Xiaoying Wang2,5, Warren J. Manning1,6, and Reza Nezafat1 1Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States, 2Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China, 3Department of Computer Science, Technical University of Munich, Munich, Germany, 4Biomedical Engineering Department, Cairo University, Giza, Egypt, 5Department of Radiology, Peking University First Hospital, Beijing, China, 6Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States Quantification of T2 in areas bordering myocardium and blood pool is challenging due to partial volume errors. Blood signal suppression would effectively reduce partial volume effects and improve image contrast at the blood-myocardium boundaries. This study proposed a Black-blood hEart-rate Adaptive T2-prepared bSSFP (BEATS) sequence for myocardial T2 mapping to improve blood-myocardial border definition. Both phantom and in vivo studies proved the advantages of BEATS sequence compared to T2prep-bSSFP T2 mapping. The proposed BEATS sequence efficiently suppresses the blood signal, resulting in better definition of blood/myocardium border by reducing the impact of partial volume effect in T2 measurements, which improves the assessment of edema post myocardial infarction.

 284 16:39 Assessment of Myocardial Fibre Architecture in Cardiac Amyloidosis Patients using In-Vivo Cardiac Diffusion Tensor Imaging Constantin von Deuster1, Alexander Gotschy1,2, Robbert J.H. van Gorkum1, Mareike Gastl1,2,3, Ella Vintschger1, Andreas Flammer2, Robert Manka1,2, Christian T. Stoeck1, and Sebastian Kozerke1 1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland, 2Department of Cardiology, University Hospital Zurich, Zurich, Switzerland, 3Dept. Cardiology, Pneumology and Angiology, Heinrich Heine University, Düsseldorf, Germany In-vivo cardiac diffusion tensor imaging (cDTI) allows imaging of alterations in the cardiac fibre architecture in diseased hearts. In this work, changes in the myocardial microstructure in patients with cardiac amyloidosis were assessed using cDTI and T1 mapping. Mean diffusivity and T1native are significantly increased in the patients and the helical fibre configuration is comparable to healthy controls. There is a trend towards higher/lower MD/FA with increased T1native, respectively. In agreement with T1 mapping, diffusion results support the presence of myocardial degeneration and emphasize the potential of cDTI as contrast agent free tool for characterizing cardiac involvement in amyloidosis patients.

 285 16:51 Cardiac Magnetic Resonance Elastography for the Diagnosis of Patients with Heart Failure with Preserved Ejection Fraction Arvin Arani1, Shivaram P. Arunachalam1, Phillip J. Rossman1, Joshua D. Trzasko1, Kevin Glaser1, Yi Sui1, Kiaran McGee1, Armando Manduca1, Barry A. Borlaug1, Richard Ehman1, and Philip Araoz1 1Radiology, Mayo Clinic, Rochester, MN, United States Heart failure with preserved ejection fraction (HFpEF) accounts for half of incident heart failure cases per year. Currently, the diagnostic reference standard is invasive.  The objective of this study is to evaluate if cardiac MR elastography (MRE) can measure increased myocardial stiffness in patients with HFpEF. Fifty-eight volunteers and 10 patients were enrolled. The mean left-ventricle myocardial stiffness of HFpEF patients (10.5±1.7 kPa) was significantly higher (p=0.002) than control subjects (8.0±1.2 kPa).This study motivates further investigation into the use of cardiac MRE as a quantitative noninvasive imaging technique to assist in the diagnosis and therapy monitoring of patients with HFpEF.

 286 17:03 Cardiac Phase-resolved Late-Gadolinium Enhancement Imaging Sebastian Weingärtner1,2,3, Burhaneddin Yaman1,2, Chetan Shenoy4, Marcel Prothmann5, Felix Wenson5, Jeanette Schulz-Menger5,6, and Mehmet Akcakaya1,2 1Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN, United States, 2Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States, 3Computer Assisted Clincial Medicine, Heidelberg University, Mannheim, Germany, 4University of Minnesota, Minneapolis, MN, United States, 5Working Group on Cardiovascular Magnetic Resonance Imaging, Max-Delbrück-Centrum and Charité -Medical University Berlin, Berlin, Germany, 6Department of Cardiology and Nephrology, HELIOS Klinikum Berlin-Buch, Berlin, Germany Late Gadolinium Enhancement (LGE) is commonly acquired during a single end-diastolic phase with inversion-recovery contrast that nulls healthy myocardial tissue. In this work, we propose a method for acquisition of cardiac phase-resolved LGE images based on an ECG triggered Look-Locker experiment with continuous FLASH imaging. Semi-quantitative evaluation of this pulsed-inversion recovery allows synthetization of LGE image contrast for all cardiac phases. Accurate functional depiction with temporal resolution up to 60 ms is obtained in healthy subjects at 3T. Images of 20 patients on a clinical 1.5T scanner show promising depiction of focal scar at a temporal resolution of 80ms.

 287 17:15 High resolution in-vivo diffusion tensor cardiovascular magnetic resonance:  a comparison of single-shot EPI and interleaved spiral trajectories with motion induced phase correction Margarita Gorodezky1,2, Andrew David Scott1,2, Pedro F Ferreira1,2, Sonia Nielles-Vallespin1,2,3, Peter D Gatehouse1,2, Dudley J Pennell1,2, and David N Firmin1,2 1Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom, 2National Heart and Lung Institute, Imperial College, London, United Kingdom, 3National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, United States The spatial resolution of DT-CMR STEAM acquisitions was increased by implementing an interleaved variable density spiral readout.  Bulk motion during STEAM diffusion encoding is unavoidably encoded in the image phase which can result in signal loss for multi-shot acquisition when the multiple interleaves are combined. A phase correction was implemented using the fully sampled centres of k-space to calculate the differences in phase between interleaves. In 7 volunteers we show improved data quality at 2.0x2.0mm2 using interleaved spirals compared to single-shot EPI and we obtain similar DT-CMR parameters.

 288 17:27 Microvascular obstruction impacts recovery of T1 and T2 relaxation and strain parameters following acute myocardial infarction Dipal Patel1, Venkat Ramanan1,2, Idan Roifman2, Mohammad Zia2, Kim A Connelly3, Graham A Wright1,2,4, and Nilesh R Ghugre1,2,4 1Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON, Canada, 2Schulich Heart Research Program, Sunnybrook Research Institute, Toronto, ON, Canada, 3Division of Cardiology, St. Michael's Hospital, Toronto, ON, Canada, 4Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada Microvascular obstruction (MVO) is a frequent complication in acute myocardial infarction (AMI). A comprehensive regional and serial characterization of tissue response in the presence and absence of MVO will help assess the high-risk patients. In this study, we utilized T1 and T2 relaxation as well as tissue strain properties to evaluate tissue response in STEMI patient’s post-AMI. We observed that measures of infarct edema, hemorrhage and strain in patients with MVO fail to recover to remote levels and have significantly lower recovery rates compared to patients without MVO. Remote T2 alterations may further be an early indicator of adverse remodeling. Our study shows that MVO impacts disease progression by hindering the regional myocardial systolic function and edema recovery post-AMI.

 289 17:39 The effects of cardiac allograft vasculopathy on intimal coronary artery wall thickness, myocardial fibrosis, and myocardial extracellular volume Ruud B van Heeswijk1,2, Jessica AM Bastiaansen1, Juan F Iglesias3, Sophie Degrauwe3, Samuel Rotman4, Jérôme Yerly1,2, Giulia Ginami1,5, Matthias Stuber1,2, and Roger Hullin3 1Radiology, Lausanne University Hospital (CHUV), Lausanne, Switzerland, 2Center for BioMedical Imaging (CIBM), Lausanne, Switzerland, 3Cardiology, Lausanne University Hospital (CHUV), Lausanne, Switzerland, 4Pathology, Lausanne University Hospital (CHUV), Lausanne, Switzerland, 5School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom Cardiac allograft vasculopathy (CAV) occurs with a high prevalence after heart transplantation (HTx) and is a major cause of mid-term to late heart transplant failure. In this study we investigated whether the presence of CAV as diagnosed by x-ray coronary angiography or intima thickness as assessed by optical coherence tomography (OCT) is linked with the myocardial T1 relaxation time, extracellular volume, or interstitial fibrosis as assessed by endomyocardial biopsies (EMB).

 290 17:51 The Difference between Extracellular Space Expansion and Diffuse Myocardia Fibrosis in Defferent Severity Distolic Dysfunction (DD) Type 2 Diabetes Mellitus (T2DM) Rhesus Monkeys using Excellelar Volume mapping and Non-contrast T1ρ mapping Yu Zhang1, Li Gong2, Yushu Chen1, Wen Zeng2, Jie Zheng3, and Fabao Gao1,2 1West China Hospital, Sichuan University, Chengdu, China, 2Sichuan Primed Bio-Tech Group Co., Ltd, Chengdu, China, 3Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, United States In this study, diffuse myocardial fibrosis was quantifitied in type 2 diabetes mellitus (T2DM) rhesus monkeys with different severity diastolic dysfunction (DD) using ECV derived from T1 mapping and mFI derived from non-contrast T1ρ mapping. Different behaviors of ECV and mFI to differentiate HC from T2DM with mild DD was observed. This reflects the difference between extracellular space expansion and collagen content during the process of myocardial fibrosis. This difference is benifite for us to better understand the pathophysiology of DD.

 291 18:03 Intravoxel incoherent motion MR imaging: Evaluation of myocardial microcirculation in diabetes patients li shi lan 1, li xin2, li zhi yong2, song qing wei1, and liu ai lian2 1Radiology, Dalian medical university, Dalian, China, 2Dalian medical university, Dalian, China Because of 80% type 2 diabetic patients died of cardiovascular complications, diabetic microangiopathy in the diabetic cardiomyopathy couldn’t be ignored. At present, we lack simple and accurate methods for assessment of myocardial microcirculation. Intravoxel incoherent motion (IVIM) technology is a new noninvasive method that can be used for quantitatively assessing myocardial microcirculation status.

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### MR Safety: PNS & RF Heating

 S06 Monday 16:15 - 18:15 Moderators: Alon Leeor & Filiz Yetisir

 292 16:15 Reduction of Peripheral Nerve Stimulation (PNS) using Pre-Excitation Targeting the Potassium System (PRE-TAPS) Mathias Davids1,2, Bastien Guérin2,3, Martin Schmelz4, Lothar R Schad1, and Lawrence L Wald2,3,5 1Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany, 2Martinos Center for Biomedical Imaging, Dept. of Radiology, Massachusetts General Hospital, Charlestown, MA, United States, 3Harvard Medical School, Boston, MA, United States, 4Department of Anesthesiology Mannheim, Heidelberg University, Mannheim, Germany, 5Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, United States PNS has become the main limitation of fast MRI using current gradient hardware. We recently presented a novel pipeline to simulate magnetically induced PNS thresholds in arbitrary coil geometries. Now, we use this framework and detailed modeling of ion dynamics and Action Potential (AP) generation to test a new strategy for PNS reduction. The method (which we call “PRE-TAPS”) pre-saturates the nerve membrane by playing gradient pulses prior to the main imaging gradient. Our model suggests that this simple pulse-sequence modification could effectively increase PNS thresholds by up to 30%.

 293 16:27 On-line Subject-Specific Local SAR Assessment by Deep Learning E.F. Meliado1,2, A.J.E. Raaijmakers1,3, M.H.F. Savenije1, A. Sbrizzi1, M. Maspero1, P.R. Luijten1, and C.A.T. van den Berg1 1Center for Image Sciences, University Medical Center Utrecht, Utrecht, Netherlands, 2MR Code BV, Zaltbommel, Netherlands, 3Biomedical Image Analysis, Eindhoven University of Technology, Eindhoven, Netherlands One of the most critical aspects that limits the application of ultra-high field MRI is the local Specific Absorption Rate (SAR) evaluation. The key aspect is that local SAR information could only be obtained by off-line simulation using generic body models, which hardly match with the patient's body and positioning. In this work we present a first deep learning approach for local SAR assessment. Results, show that the relation between local SAR on the one hand and MR Dixon images and B1-field maps on the other hand, can be accurately and instantaneously mapped by a Convolutional Neural Network (CNN).

 294 16:39 NEUROMAN: Reference Computational Human Phantoms for Evaluation of Safety Thresholds for Peripheral Nerve Stimulation Bryn A Lloyd1, Antonino Cassarà1, Silvia Farcito1, Esra Neufeld1, Beom Sun Chung2, Jin Seo Park3, Min Suk Chung2, and Niels Kuster1,4 1IT'IS Foundation, Zürich, Switzerland, 2Department of Anatomy, Ajou University, Suwon, Republic of Korea, 3Department of Anatomy, Dongguk University, Gyeongju, Republic of Korea, 4ETH, Zürich, Switzerland The trend towards stronger magnetic fields and/or faster gradient switching in magnetic resonance imaging poses safety risks for patients, e.g., due to tissue heating and unwanted neurostimulation. The IEEE-ICES TC95 SC6 was formed to re-evaluate nerve excitation safety thresholds in response to temporal and spatial characteristics of electric fields induced by externally applied fields or implants. To this end, we are developing reference human anatomical models with unprecedented details in the peripheral nervous system, connectivity to organs and muscles, and functionalized with compartmental nerve models to investigate interactions with neuronal electrophysiology. We employ these phantoms to investigate current safety guidelines.

 295 16:51 Workflow proposal for defining SAR safety margins in parallel transmission Nicolas Boulant1, Vincent Gras1, Alexis Amadon1, Michel Luong2, Guillaume Ferrand2, and Alexandre Vignaud1 1NeuroSpin, CEA, Saclay, France, 2Irfu, CEA, Saclay, France SAR calculations in parallel transmission (pTx) typically rely on electromagnetic simulations performed on generic models. Uncertainties however often exist due to tolerances in the lumped element values, cable losses, phase offsets and different coupling between transmit elements. Additional uncertainties in SAR evaluation include intersubject variability and exam supervision. In this work, we review a workflow that has been implemented in our laboratory with home-made and commercial pTx coils at 7T. Based on this strategy, nearly 100 healthy volunteers have been scanned with no reported incidents, while still allowing to exploit pTx to mitigate efficiently the RF inhomogeneity problem.

 296 17:03 SAR estimation error due to body model mismatch for fetal imaging at 3 Tesla Filiz Yetisir1, Esra Abaci Turk1, Bastien Guerin2,3, Borjan Gagoski1, Natalie Copeland1, P. Ellen Grant1, Lawrence L. Wald2,3,4, and Elfar Adalsteinsson5,6 1Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Boston, MA, United States, 2A.A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, United States, 3Harvard Medical School, Boston, MA, United States, 4Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Boston, MA, United States, 5Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States, 6Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, United States RF safety concerns have been raised for both the mother and the fetus for 3 T fetal MRI. Parallel transmission can address these concerns by reducing the maternal and fetal SAR however it also relies on one or more body models to predict that individual’s local SAR. In this work, we assess the range of error incurred when various pregnant or non-pregnant models are used to predict SAR in pregnant patients. We model the degree of over or underestimation of SAR in 56 combinations of model/patient and find a maximum SAR under/over-estimation of 59%/142%.

 297 17:15 Optimizing the Topography of Transmit Coils for SAR Management Alireza Sadeghi-Tarakameh1,2, Angel Torrado-Carvajal3, Cemre Ariyurek1,2, Ergin Atalar1,2, Gregor Adriany4, Gregory J. Metzger4, Russell L. Lagore4, Lance DelaBarre4, Andrea Grant4, Pierre-Francois Van de Moortele4, Kamil Ugurbil4, and Yigitcan Eryaman4 1Electrical and Electronics Engineering Department, Bilkent University, Ankara, Turkey, 2National Magnetic Resonance Research Center (UMRAM), Ankara, Turkey, 3Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States, 4Center for Magnetic Resonance Research (CMRR), University of Minnesota, Minneapolis, MN, United States Specific absorption rate (SAR) is a significant issue for ultra-high field (UHF, B0≥7T) imaging. In this study, we investigate a strategy based on optimizing the topography of transmit elements in 3D (i.e., adding bumps to a resonant planar structure) in order to reduce the local SAR while keeping B1+ efficiency constant inside a region of interest. For proof of concept, we modified three different resonant structures and compared their performance to previous designs with EM simulations. In addition, we built one of the proposed design and experimentally tested it using a whole-body 10.5T scanner.

 298 17:27 Magnetic resonance imaging in patients with cardiac implanted electrical devices: single centre two year experience including thoracic imaging and non-MRI conditional devices. Joseph Martin1,2, Anish N Bhuva3,4, Peter Kellman5, Redha Boubertakh1,6, Marc E Miquel1,6, Matthieu Ruthven1, Adam Graham Graham3, Patricia Feuchter3, Angela Hawkins3, Richard Schilling3, James C Moon3, Martin Lowe Lowe3, Neha Sekhri3, and Charlotte Manisty3,4 1Clinical Physics, Barts Health NHS Trust, London, United Kingdom, 2Medical Physics and Engineering, Kings College London, London, United Kingdom, 3Department of Cardiovascular Imaging, Barts Heart Centre, Barts Health NHS Trust, London, United Kingdom, 4Institutes for Cardiovascular Science, University College London, London, United Kingdom, 5National Institutes of Health, Bethesda, MD, United States, 6William Harvey Research Institute, Queen Mary University of London, London, United Kingdom Over a million patients worldwide have cardiac implantable electronic devices (CIEDs), with a 50-75% lifetime MRI requirement.  Although conventionally contraindicated, MRI-conditional CIEDs and evidence supporting safer scanning of non-MRI conditional CIEDs are changing practice. We report single center experience of CIED MRI scanning over 24 months. 179 MRI scans were acquired, 31% non-MRI conditional devices, 79% thoracic scans.  Clinical impact was high (including cancer diagnosis and treatment planning, suspected cord compression and stroke). All patients were safely scanned with no clinically-significant events or device parameter changes resulting from MRI. These data support increased provision of MRI to CIED patients.

 299 17:39 Exploring the impact of nulling currents on a cardiac guidewire in reducing worst case SAR at 1.5T J. Nuno Teixeira1, Felipe Godinez1, Shaihan Malik1, and Jo V. Hajnal1 1Division of Imaging Sciences and Biomedical Engineering, King's College London, London, United Kingdom MRI with non-MR compatible objects, namely wires, poses several challenges as risks of high Local SAR and reduced image quality due to B1 enhancement. In this work we looked at previously proved current nulling techniques and at their relationship with the reduction of worst case SAR scenarios. Results showed that current nulling leads to large reductions in worst case SAR, but that performance varies with coil design and sensor location. The analysis could be used to aid design of experimental setup for maximum safety.

 300 17:51 Reduction of the absorbed power around electrode tips in deep brain stimulation patients using pTx: Impact of number and arrangement of channels Bastien Guerin1,2, Darin Dougherty2,3, and Lawrence L. Wald1,2 1Radiology, Massachusetts General Hospital, Charlestown, MA, United States, 2Harvard Medical School, Boston, MA, United States, 3Psychiatry, Massachusetts General Hospital, Charlestown, MA, United States We assess the potential of pTx for reduction of the absorbed power around electrode tips (APAET) in DBS patients using a realistic DBS patient model and electromagnetic field co-simulation. We simulate 5 coils, including a birdcage coil driven in quadrature and as a 2-channel pTx coil as well as four pTx coils with up to 16 channels arranged in up to two rows. We compare magnitude least square pulses with explicit constraints on the APAET and global SAR. We show that pTx, especially using head-only arrays, has the potential to alleviate the safety problem of DBS patients at 3 Tesla.

 301 18:03 Comparison between experimental and simulated electric fields near a hip implant in a parallel transmit hip coil Aurelien Destruel1, Miguel Fuentes1,2, Ewald Weber1, Kieran O'Brien3,4, Markus Barth4, Feng Liu1, and Stuart Crozier1 1School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, Australia, 2School of Public Health and Preventive Medicine, Population Health Research on Electromagnetic Energy, Monash University, Australia, 3Siemens Healthcare Pty Ltd, Brisbane, Australia, 4Centre for Advanced Imaging, The University of Queensland, Brisbane, Australia The high conductivity of metal implants causes them to focus electric fields in tissue, which may increase the local temperature. In the case of parallel transmit (pTx) MRI, careful simulations of the patient and coil are required to predict heating, but validation of the simulations is challenging near metal implants. In this work, direct measurement of E-field near a hip prosthesis is performed inside a pTx hip coil, and results are compared with simulated data with and without considering decoupling. Neglecting decoupling leads to differences of up to 80% with measured data, showing the importance of realistic simulations.

Oral

### Arterial Spin Labeling

 W03/04 Monday 16:15 - 18:15 Moderators: Weiying Dai & David Thomas

 302 16:15 Advanced Automatic Planning for Super-Selective Arterial Spin Labeling Flow Territory Mapping Michael Helle1, Fabian Wenzel1, Kim van de Ven2, and Peter Boernert1 1Philips Research, Hamburg, Germany, 2Philips Healthcare, Best, Netherlands This study presents an advanced fully automated approach based on vessel detection and analysis. It is completely integrated in the scanner console and allows labeling of the major brain feeding vessels in an efficient and robust way. Average processing time to find optimal labeling positions for all major brain feeding arteries is <15 seconds.

 303 16:27 Non-contrast assessment of blood-brain-barrier permeability with water-extraction-with-phase-contrast-arterial-spin-tagging (WEPCAST) MRI Zixuan Lin1, Yang Li1, Pan Su1, Deng Mao1, Zhiliang Wei1, Jay Pillai1, Abhay Moghekar2, Matthias van Osch3, Yulin Ge4, and Hanzhang Lu1 1Department of Radiology, Johns Hopkins University, Baltimore, MD, United States, 2Department of Neurology, Johns Hopkins University, Baltimore, MD, United States, 3Department of Radiology, Leiden University Medical Center, Leiden, Netherlands, 4Department of Radiology, New York University Langone Medical Center, New York, NY, United States A new method for non-contrast assessment of blood-brain-barrier (BBB) permeability to water has been proposed: water-extraction-with-phase-contrast-arterial-spin-tagging (WEPCAST) MRI, which allows selective imaging of venous ASL signal. Studies were performed to show proof-of-principle and Look-Locker readout were applied to expedite data acquisition. The results were consistent with previous literature. Mild hypercapnia was also shown to enhance the sensitivity of the technique significantly.

 304 16:39 Investigation into water transport mechanisms in the brain using a combination of T2 measurements and crusher gradients with ASL Leonie Petitclerc1, Sophie Schmid1,2, Wouter M. Teeuwisse1,2, and Matthias J. P. van Osch1,2 1C.J. Gorter Center for High Field MRI, Radiology, Leiden University Medical Center, Leiden, Netherlands, 2Leiden Institute of Brain and Cognition, Leiden, Netherlands TRUST and crusher gradients were combined with time-encoded pCASL to examine the transport of water from the vasculature to the tissue in the brain. At early time points, where the intravascular portion of the ASL signal is high, the crusher gradients resulted in a large reduction in the average signal. By comparing the intravascular fraction obtained from crushed signal to T2 measurements, it was observed that the change in T2 is greater in later time points than the change in intravascular fraction. This suggests that T2 methods are more sensitive to alterations in the blood-brain barrier than crusher gradient techniques.

 305 16:51 Arterial Spin Labeled Input Function (ASLIF): signal acquisition during pseudo-continuous arterial spin labeling Matthias Günther1,2,3 1Fraunhofer MEVIS, Bremen, Germany, 2University Bremen, Bremen, Germany, 3mediri GmbH, Heidelberg, Germany In ASL pseudo-continuous labeling (pCASL) is often used as a labelling scheme due to its increased SNR compared to pulsed variants. After labeling and a subsequent post-labeling delay, the amount of labeled blood in the organ of interest is acquired. In this abstract, we describe a new approach, which allows to measure the blood signal while it is labeled. Results are presented for a four-phase Hadamard-encoded pCASL sequence. This will ultimately allow for a realtime monitoring of the arterial input function in pCASL.

 306 17:03 Time-encoded golden angle radial ASL Merlijn C.E. van der Plas1, Sophie Schmid1, Maarten Versluis2, and Matthias J.P. van Osch1 1C.J. Gorter Center for high field MRI, Department of Radiology, Leiden University Medical Center, Leiden, Netherlands, 2Philips, Best, Netherlands The golden angle readout provides a flexible approach to acquire multiple reconstructions, each with a different trade-off between spatial and temporal resolution from the same dataset. In combination with a Hadamard labeling scheme, the golden angle readout can be optimized for reconstructions at multiple spatial resolutions, allowing for multi-slice acquisition. By changing to single-slice acquisition, high temporal resolution angiography and high quality perfusion images can be reconstructed from a single dataset.

 307 17:15 Cerebral Blood Volume Mapping using Fourier-Transform based Velocity-Selective Saturation Pulse Trains Qin Qin1,2, Yaoming Qu3, Wenbo Li1,2, Dapeng Liu1,2, Taehoon Shin4,5, Doris Lin1, Peter van Zijl1,2, and Zhibo Wen3 1Johns Hopkins University, Baltimore, MD, United States, 2F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States, 3Department of Radiology, Zhujiang Hospital, Southern Medical University, Guangzhou, China, 4Ewha Womans University, Seoul, Republic of Korea, 5Case Western Reserve University, Cleveland, OH, United States A new non-contrast cerebral blood volume (CBV) quantification technique is proposed using Fourier-transform based velocity-selective saturation (FT-VSS) pulse trains. Its utility is assessed for healthy subjects at 3T and compared to a method using conventional flow-dephasing VS pulse trains. FT-VSS showed greater immunity to gradient imperfections and up to 40% higher SNR. The better performance of FT-VSS pulse trains in CBV measurements can be explained by the effective background suppression related to its velocity-selective profile: static tissue signal in the saturation band and flowing spins in the passband, which is opposite from the velocity response of the conventional method.

 308 17:27 Robust estimation of quantitative perfusion from multi-phase pseudo-continuous arterial spin labelling Michael A Chappell1, Martin Craig1, James R Larkin2, Manon A Simard2, Nicola R Sibson2, and Thomas W Okell3 1Institute of Biomedical Engineering, University of Oxford, Oxford, United Kingdom, 2Cancer Research UK & Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, United Kingdom, 3Wellcome Centre for Integrative Neuroimaging, FMRIB, University Oxford, Oxford, United Kingdom Multi-phase pcASL has been proposed as a means to achieve accurate perfusion quantification that is robust to imperfect shim in the labelling plane. There exists a previously unrecognised bias in the estimation process that is a function of noise on the data. In this work this boas is addressed, exploiting information common to voxels containing tissue fed by the same artery, identified using clustering methods.

 309 17:39 Optimized Scan Design for ASL Fingerprinting and Multiparametric Estimation using Neural Network Regression Anish Lahiri1, Jeffrey A Fessler1, and Luis Hernandez-Garcia2 1Dept of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, United States, 2FMRI Laboratory, University of Michigan, Ann Arbor, MI, United States We investigate an optimization method for ASL fingerprinting acquisition schemes as well as a neural network framework for estimating hemodynamic parameters from the data.

 310 17:51 Improving Perfusion Image Quality and Quantification Accuracy Using Multi-contrast MRI and Deep Convolutional Neural Networks Jia Guo1, Enhao Gong2, Maged Goubran1, Audrey P. Fan1, Mohammad M. Khalighi3, and Greg Zaharchuk1 1Radiology, Stanford University, Stanford, CA, United States, 2Electrical Engineering, Stanford University, Stanford, CA, United States, 3Global Applied Science Lab, GE Healthcare, Menlo Park, CA, United States We propose a novel method that uses deep convolutional neural networks (dCNNs) to combine multiple contrasts from MRI, including single- and multi-delay pseudo-continuous arterial spin labeling (PCASL) and structural scans, to synthesize perfusion maps that approach the accuracy of the PET perfusion measurements. The dCNN was trained and tested on both healthy and patient datasets, and demonstrated significant improvement on both image quality (higher structural similarity and lower normalized root mean square error) and quantification accuracy (regional CBF comparable with PET) than either ASL method alone. This method may potentially be generalized to other qualitative/quantitative applications.

 311 18:03 Acceleration of arterial spin labeling data acquisition using spatio-temporal total generalized variation (TGV) reconstruction Stefan Manfred Spann1, Christoph Stefan Aigner1, Matthias Schloegl1, Andreas Lesch1, Kristian Bredies2, Stefan Ropele3, Daniela Pinter3, Lukas Pirpamer3, and Rudolf Stollberger1,4 1Institute of Medical Engineering, Graz University of Technology, Graz, Austria, 2Institute of Mathematics and Scientific Computing, University of Graz, Graz, Austria, 3Department of Neurology, Medical University of Graz, Graz, Austria, 4BioTechMed-Graz, Graz, Austria 3D imaging sequences such as GRASE or RARE-SoSP are the preferable choice for acquiring ASL images. However, a tradeoff between the number of segments and blurring in the images due to the T2 decay has to be chosen. In this study we propose a reconstruction algorithm based on total generalized variation for reducing the number of segments and therefore the acquisition time of one image. We incorporate the averaging procedure in the reconstruction process instead of reconstructing each image individually. This allows exploiting temporal redundancy and spatial similarity for improving the reconstruction quality of ASL images.

Study Groups

### MR Flow & Motion Quantitation Business Meeting

 W07 Monday 17:15 - 18:15 (no CME credit)

Study Groups

### Placenta & Fetus Business Meeting

 W08 Monday 17:15 - 18:15 (no CME credit)

Event

 W03/04 Monday 18:30 - 19:30 (no CME credit)

Event

### Manuscript Reviewing for ISMRM's Scientific Journals

 W05/06 Monday 18:30 - 19:30 (no CME credit)

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Sunrise Session

### Tractography in the Operating Theatre

Organizers: Stephan Maier, Jennifer McNab, Noam Shemesh

 N03 Tuesday 7:00 - 7:50 Moderators: Qiyuan Tian & Chris Clark

 7:00 Next-Generation Diffusion Anisotropy Mapping Techniques for Neurosurgery Timothy Shepherd

 7:25 Using Tractography to Guide Tumor Resections Natalie Voets

 7:50 Adjournment & Meet the Teachers

Sunrise Session

### Go Faster in Clinical Imaging: Multiband Imaging

Organizers: Jongho Lee, Utaroh Motosugi, Yi-Fen Yen

 N04 Tuesday 7:00 - 7:50 Moderators: Koji Sakai & Yi-Fen Yen

 7:00 Basic Physics of Multiband Imaging Berkin Bilgic

 7:25 Clinical Applications of Multiband Imaging Seung Hong Choi

 7:50 Adjournment & Meet the Teachers

Sunrise Session

### From Diagnosis to Assessing Therapy Response: Gynecological Malignancy

Organizers: Kathryn Fowler, Catherine Hines, Kartik Jhaveri, Lorenzo Mannelli, Valeria Panebianco, Scott Reeder, Reiko Woodhams

 S01 Tuesday 7:00 - 7:50 Moderators: Victoria Chernyak & Jeffrey Brown

 7:00 Pre-Treatment Andrea Rockall

 7:25 Monitoring response to therapy Nandita deSouza

 7:50 Adjournment & Meet the Teachers

Sunrise Session

### Advanced Techniques in Cardiovascular MR: Imaging Cardiac Microstructure & Physiology

Organizers: Sebastian Kozerke, Reza Nezafat

 S02 Tuesday 7:00 - 7:50 Moderators: Jessica Bastiaansen & Angus Lau

 7:00 Imaging Cardiac Metabolism Marie Schroeder

 7:25 Imaging of Cardiac Microstructure Christian Stoeck

 7:50 Adjournment & Meet the Teachers

Sunrise Session

### Application of Molecular Imaging in Cardiovascular Diseases

Organizers: Guanshu Liu, Natalie Serkova, Damian Tyler

 S03 Tuesday 7:00 - 7:50 Moderators: Fabao Gao & Damian Tyler

 7:00 Recent Technical Developments of Molecular Imaging in Cardiovascular Diseases Michal Neeman

 7:50 Adjournment & Meet the Teachers

Sunrise Session

### Emerging Methods in MSK MRI: Cartilage

Organizers: Eric Chang, Garry Gold, Emily McWalter, Edwin Oei, Philip Robinson

 S04 Tuesday 7:00 - 7:50 Moderators: Emily McWalter & Sander Brinkhof

 7:00 Physiologic Articular Cartilage Imaging Stefan Zbyn

 7:25 Clinical Articular Cartilage Imaging with Emerging MR Methods Pia Jungmann

 7:50 Adjournment & Meet the Teachers

Sunrise Session

### Your Brain on Drugs: Brains & Drugs

Organizers: Andre Obenaus, Pia Maly Sundgren

 S05 Tuesday 7:00 - 7:50 Moderators: Minming Zhang & Christopher Smyser

 7:00 Nicotine - Effects in Brain Functional Connectivity Victor Vergara

 7:25 Imaging of the Developing Brain Serena Counsell

 7:50 Adjournment & Meet the Teachers

Sunrise Session

### Maker: B0

Organizers: Gregor Adriany, Matthias Günther, Michael Hansen, Christoph Juchem, Greig Scott

 S06 Tuesday 7:00 - 7:50 Moderators: Mary McDougall & Greig Scott

 7:00 Techniques for Generating a Field Patrick Goodwill

 7:25 Magnet-Building Tutorial Jason Stockmann

 7:50 Adjournment & Meet the Teachers

 Exhibition Hall 1554-1573 Tuesday 8:15 - 10:15 (no CME credit)

Electronic Poster: General Cancer Imaging

 Exhibition Hall Tuesday 8:15 - 9:15 (no CME credit)

Electronic Poster: Spectroscopy & Non-Proton MR

 Exhibition Hall Tuesday 8:15 - 9:15 (no CME credit)

Member-Initiated Symposium

### Peripheral Nerve Stimulation: Have We Hit the Limits?

Organizers: Michael Steckner

 S06 Tuesday 8:15 - 10:15 (no CME credit)

 8:15 Introduction & Overview Michael Steckner1 1TMRU

 8:20 PNS Investigations, Unresolved Issues & Novel Solutions Blaine Chronik1 1University of Western Ontario

 8:43 Exploring the PNS Characteristics of the Connectome Gradients Ralph Kimmlingen1 1Siemens Healthineers

 9:06 State-of-Art Neuron Models Habib Bousleiman

 9:29 A New Neuron Model for MRI Exposures Mathias Davids1 1Heidelberg University, Mannheim, Germany

 9:52 Cardiac Implant Vendor Understanding of Electric Field Threshold Values Necessary to Stimulate the Heart Jonathan Edmonson1 1Medtronic, Inc.

Member-Initiated Symposium

### How to Make Perfusion Imaging Become a Quantitative Imaging Biomarker

Organizers: Linda Knutsson, Esben Petersen, Sophie Schmid

 W03/04 Tuesday 8:15 - 10:15 Moderators: Eric Achten & Linda Knutsson (no CME credit)

 8:15 What is QIBA? Alexander Guimaraes1 1Oregon Health Sciences University, United States

 8:30 What is EIBALL? Nandita M deSouza1 1Institute of Cancer Research, Surrey, United Kingdom

 8:45 QIBA Profile on DSC Ona Wu1 1MGH Athinoula A Martinos Center, Charlestown, MA, United States

 9:00 QIBA Profile on DCE Caroline Chung

 9:15 QIBA Profile on ASL Xavier Golay1 1Gold Standard Phantoms Limited

 9:30 QA in Clinical Trials Using Phantoms Joshua S. Greer1 1Radiology, UT Southwestern Medical Center, Dallas, TX, United States

 9:45 Panel Discussion

Weekday Course

### Imaging Metabolism in the Developing Brain

Organizers: Christopher Smyser, Pia Maly Sundgren

 S01 Tuesday 8:15 - 10:15 Moderators: Christopher Smyser

 8:15 Glucose & the Developing Brain: What Do We Know? Manu S. Goyal1 1Washington University

 8:45 Effects of Nutrition on Brain Development Manon Benders1 1University Medical Center Utrecht, Netherlands

 9:15 Using MRI/S to Study Metabolic Signatures of Early Brain Development & Disease Noriko Aida1,2 and Moyoko Tomiyasu1,2 1Kanagawa Children's Medical Center, Kanagawa, Japan, 2National Institute of Radiological Sciences, Chiba, Japan In the developing brain, metabolites concentrations such as NAA, choline and myo-inositol show dynamic change. We can use 1H-MRS to measure such metabolite concentrations. It is important to know such signature for the precise evaluation of neonatal brain pathology, particularly in hypoxic-ischemic encephalopathy. 1H-MRS is also a powerful tool for the diagnosis and disease monitoring forpediatric neuro-metabolic diseases.

 9:45 Advanced Neuroimaging Techniques to Study Brain Metabolism in Pediatric Populations Stefan Bluml1,2 1USC/Childrens Hospital Los Angeles, United States, 2Rudi Schulte Research Institute, Santa Barbara, CA, United States In this presentation, various methods that have been used or could potentially be used to study metabolism in the pediatric brain are presented. Beyond widely available proton (1H) MR spectroscopy, this includes phosphorus (31P) MRS, carbon 13 (13C) MRS methods as well as MR imaging approaches that measure the cerebral metabolic rate of oxygen.

 10:15 Adjournment & Meet the Teachers

Power Pitch

### Pitch: Neuro Acquisition: Seeing the CNS Better

 Power Pitch Theater A - Exhibition Hall Tuesday 8:15 - 9:15 Moderators: Douglas Noll & Peder Larson (no CME credit)

 312 8:15 Imaging of the Thoracic Spinal Cord using Radially Sampled Averaged Magnetization Inversion Recovery Acquisitions (rAMIRA) Matthias Weigel1,2, Tanja Haas1,3, and Oliver Bieri1,2 1Division of Radiological Physics, Dept. of Radiology, University Hospital Basel, Basel, Switzerland, 2Dept. of Biomedical Engineering, University of Basel, Basel, Switzerland, 3Dept. of Radiology, University Hospital Basel, Basel, Switzerland

 313 8:15 FLAWS imaging improves depiction of the thalamic subregions for DBS planning in epileptic patients Elise Bannier1,2, Giulio Gambarota3,4, Jean-Christophe Ferré1,2, Tobias Kober5,6,7, Anca Nica8, Stephan Chabardes9, and Claire Haegelen3,4,10 1Radiology, University Hospital of Rennes, Rennes, France, 2VISAGES ERL U-1228, Univ Rennes, Inria, CNRS, Inserm, IRISA UMR 6074, Rennes, France, 3LTSI, Université de Rennes 1, Rennes, France, 4U1099, INSERM, Rennes, France, 5Advanced Clinical Imaging Technology, Siemens Healthcare AG, Lausanne, Switzerland, 6Radiology, University Hospital Lausanne (CHUV), Lausanne, Switzerland, 7Signal Processing Laboratory, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, 8Neurology, University Hospital of Rennes, Rennes, France, 9Neurosurgery, University Hospital of Grenoble, Grenoble, France, 10Neurosurgery, University Hospital of Rennes, Rennes, France

 314 8:15 Silent T2* Encoding using ZTE Combined with Gradient-Echo Burst (BURZTE) Rolf F Schulte1, Guido Buonincontri2, Mauro Costagli2, Anne Menini3, Florian Wiesinger1, and Ana Beatriz Solana1 1GE Healthcare, Munich, Germany, 2IMAGO7 Foundation, Pisa, Italy, 3GE Healthcare, Menlo Park, CA, United States

 315 8:15 Using 3D high-resolution MR Fingerprinting (MRF) to assist detection and characterization of epileptic lesions Dan Ma1, Irene Wang2, Imad Najm2, Anagha Deshmane3, Debra McGivney1, Ken Sakaie4, Mark Lowe4, Vikas Gulani1, Mark Griswold1, and Stephen Jones4,5 1Radiology, Case Western Reserve University, Cleveland, OH, United States, 2Epilepsy Center, Cleveland Clinic, Cleveland, OH, United States, 3Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tuebingen, Germany, 4Imaging Institute, Cleveland Clinic, Cleveland, OH, United States, 5Neuroradiology, Cleveland Clinic, Cleveland, OH, United States

 316 8:15 An Optimized Single-shot Sequence for Fast T2w Imaging of the Brain Mahesh Bharath Keerthivasan1,2, Blair Winegar2, Unni Udayasankar2, Ali Bilgin1,3, Maria Altbach2, and Manojkumar Saranathan2 1Electrical and Computer Engineering, University of Arizona, Tucson, AZ, United States, 2Medical Imaging, University of Arizona, Tucson, AZ, United States, 3Biomedical Engineering, University of Arizona, Tucson, AZ, United States

 317 8:15 The UK7T Network – optimized design of a multi-site, multi-vendor travelling heads study. William T Clarke1, Olivier Mougin2, Ian D Driver3, Catarina Rua4, Andrew T Morgan5, Stuart Clare1, Susan Francis2, Richard Wise3, Adrian Carpenter4, Keith Muir5, and Richard Bowtell2 1Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom, 2Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, United Kingdom, 3Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, United Kingdom, 4Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom, 5Institute of Neuroscience & Psychology, University of Glasgow, Glasgow, United Kingdom

 318 8:15 Evaluation of a wave-MPRAGE sequence for brain morphometery Ross W. Mair1,2, Jared A. Nielsen1,3,4, and Randy L. Buckner1,2,3,4 1Center for Brain Science, Harvard University, Cambridge, MA, United States, 2AA Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 3Department of Psychology, Harvard University, Cambridge, MA, United States, 4Department of Psychiatry, Massachusetts General Hospital, Charlestown, MA, United States

 319 8:15 Methods to accelerate STAGE: Toward 8 min for Twelve 3D images on 1.5T Aiqi Sun1, Feng Huang1, Yu Wang1,2, Wei Xu1, Yiran Wang1, Hongyu Guo1, Yongsheng Chen3,4,5, and Ewart Mark Haccke2,3,5 1Neusoft Medical System, Shanghai, China, 2Shanghai Key Laboratory of Magnetic Resonance, East China Normal University, Shanghai, China, 3The MRI Institute for Biomedical Research, Detroit, MI, United States, 4Sino-Dutch Biomedical and Information Engineering School, Northeastern University, Shenyang, China, 5Department of Radiology, School of Medicine, Wayne State University, Detroit, MI, United States

 320 8:15 Accelerated quantitative susceptibility and R2* mapping with flexible k-t-segmented 3D-EPI Rüdiger Stirnberg1, Andreas Deistung2,3,4, Jürgen Reichenbach2, and Tony Stöcker1,5 1MR Physics, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany, 2Medical Physics Group, Institute of Diagnostic and Interventional Radiology, University Hospital Jena, Jena, Germany, 3Department of Neurology, Essen University Hospital, Essen, Germany, 4Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, Essen, Germany, 5Department of Physics and Astronomy, University of Bonn, Bonn, Germany

 321 8:15 Myelin Lipid 1H Density Measurements by IR-UTE are Consistent Before and After D2O Exchange Alan C Seifert1,2, Michael J Wilhelm3, Suzanne L Wehrli4, and Felix W Wehrli1 1Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 3Department of Chemistry, Temple University, Philadelphia, PA, United States, 4SAIF Core Facility, Children's Hospital of Philadelphia, Philadelphia, PA, United States

 322 8:15 Formalin Tissue Fixation Biases Myelin Density Measurement by Quantitative Magnetization Transfer and Myelin Water Imaging Alan C Seifert1,2,3, Melissa Umphlett4, Mary Fowkes4, and Junqian Xu1,2,3,5 1Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 2Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 3Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 4Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 5Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, United States

 323 8:15 High Resolution Diffusion Tensor Imaging of the Hippocampus in Temporal Lobe Epilepsy Sarah Treit1, Trevor Steve2, Tom Nowacki2, Graham Little1, Christian Beaulieu1, and Donald W Gross2 1Biomedical Engineering, University of Alberta, Edmonton, AB, Canada, 2Neurology, University of Alberta, Edmonton, AB, Canada

 324 8:15 Repeatability of measuring pulsatile brain tissue motion and volumetric strain with retrospectively-gated DENSE at 7T Ayodeji L. Adams1, Jacob-Jan Sloots1, Peter R. Luijten1, and Jaco J. M. Zwanenburg1 1Radiology, University Medical Center Utrecht, Utrecht, Netherlands

 325 8:15 Isotropic 3D quantification of R1 and R2 relaxation and proton density in 6 minutes scan time Marcel Warntjes1,2, Peter Johansson1, Anders Tisell3,4, and Peter Lundberg3 1SyntheticMR, Linköping, Sweden, 2Center for Medical Imaging Science and Visualization (CMIV), Linköping, Sweden, 3Radiation Physics, Linköping, Sweden, 4Center for Medical Imaging Science and Visualization (CMIV), Linkoping, Sweden

 326 8:15 Zero Time of Echo imaging with an Adiabatic Fat Suppression Pulse at 7T Mark Symms1, Mauro Costagli2,3, Guido Buonincontri2,3, Florian Wiesinger4, Doug Kelley5, Martin A Janich4, Giacomo Aringhieri2,6, Massimo Marletta2,6, Gareth Barker7, Virna Zampa2,6, Mirco Cosottini2,6, and Michela Tosetti2,3 1GE Healthcare, Pisa, Italy, 2Imago7, Pisa, Italy, 3IRCCS Stella Maris, Pisa, Italy, 4GE Healthcare, Munich, Germany, 5GE Healthcare, Waukesha, WI, United States, 6University of Pisa, Pisa, Italy, 7King's College London, London, United Kingdom

Power Pitch

 Power Pitch Theater B - Exhibition Hall Tuesday 8:15 - 9:15 Moderators: Eric Sigmund & Karyn Chappell (no CME credit)

 327 8:15 Intramuscular variability and sex difference in diffusion properties and 3D architecture of human lower leg muscles assessed with ultra-high-field diffusion tensor imaging and tractography Alexandre Fouré1, Augustin C Ogier1, Christophe Vilmen1, Arnaud Le Troter1, Thorsten Feiweier2, Maxime Guye1,3, Julien Gondin4, Pierre Besson1, and David Bendahan1 1Aix-Marseille Univ, CNRS, CRMBM, Marseille, France, 2Siemens Healthcare, Erlangen, Germany, 3APHM, Hôpital Universitaire Timone, CEMEREM, Marseille, France, 4Institut NeuroMyoGène, Université Claude Bernard Lyon 1, INSERM, CNRS, Villeurbanne, France

 328 8:15 Time-dependent diffusion and the random permeable barrier model predict muscles fiber dimensions in Duchenne muscular dystrophy mice Bauke Kogelman1, Kevin Adamzek2, Ernst Suidgeest1, Gregory Lemberskiy3, Dmitry S. Novikov3, Els Fieremans3, Maaike van Putten2, and Louise van der Weerd1,2 1Radiology, Leiden University Medical Center, Leiden, Netherlands, 2Human Genetics, Leiden University Medical Center, Leiden, Netherlands, 3Radiology, New York University School of Medicine, New York, NY, United States

 329 8:15 Relationship of paraspinal muscle DTI metrics to isometric strength measurements Elisabeth Klupp1, Barbara Cervantes2, Sarah Schlaeger2, Stephanie Inhuber3, Florian Kreuzpointer3, Michael Dieckmeyer2, Friedemann Freitag2, Ernst J. Rummeny2, Claus Zimmer1, Jan S. Kirschke1, Dimitrios C. Karampinos2, and Thomas Baum1 1Department of Diagnostic and Interventional Neuroradiology, Klinikum rechts der Isar, Technische Universität München, München, Germany, 2Department of Diagnostic and Interventional Radiology, Klinikum rechts der Isar, Technische Universität München, München, Germany, 3Department of Sport and Health Sciences, Technische Universität München, München, Germany

 330 8:15 Imaging human motor unit activity using MRI. Paola Porcari1, Ian Schofield2, Roger Whittaker3, and Andrew M Blamire4 1Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom, 2Newcastle University, Newcastle upon Tyne, United Kingdom, 3Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom, 4Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom

 331 8:15 Clinical Feasibility of Isotropic MAVRIC SL Imaging of Total Joint Arthroplasties Matthew F. Koff1, Suryanarayanan Kaushik2, Parina H. Shah1, Erin G. Argentieri1, and Hollis G. Potter1 1Hospital for Special Surgery, New York, NY, United States, 2General Electric Healthcare, Waukesha, WI, United States

 332 8:15 Solid-State MRI as a noninvasive alternative to computed tomography for craniofacial imaging Hyunyeol Lee1, Xia Zhao1, Hee Kwon Song1, Rosaline Zhang2, Scott P Bartlett2, and Felix W Wehrli1 1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Plastic Surgery, University of Pennsylvania, Philadelphia, PA, United States

 333 8:15 Subregional bone marrow adipose tissue composition in the proximal femur: Comparison of 3T Chemical Shift Encoded-MRI and Magnetic Resonance Spectroscopy Dimitri MARTEL1, Benjamin LEPORQ2, Mary BRUNO1, Stephen HONIG3, Amit SAXENA4, H.Michael BELMONT4, Gabrielle TURYAN1, Ravinder R. REGATTE1, and Gregory CHANG1 1Radiology, NYU Langone Health, New York, NY, United States, 2Université de Lyon; CREATIS CNRS UMR 5220, Inserm U1206, INSA-Lyon, UCBL Lyon 1, Villeurbanne, France, 3Osteoporosis Center, Hospital for Joint Diseases, NYU Langone Health, New York, NY, United States, 4Department of Rheumatology, NYU Langone Health, New York, NY, United States

 334 8:15 Temporal Changes of a Canine Model of Patellar Tendinopathy Using UTE MRI T2* Assessment: A Pilot Study Sarah G. Pownder1, Kei Hayashi2, Brian G. Caserto3, Bin Lin1, Hollis G. Potter1, and Matthew F. Koff1 1Department of Radiology and Imaging - MRI, Hospital for Special Surgery, New York, NY, United States, 2Cornell University, Ithaca, NY, United States, 3VetPath Services, Stone Ridge, NY, United States

 335 8:15 Knee Cartilage UTE T2* Quantification with Water-Fat Decomposition Misung Han1, Peng Cao1, Michael Carl2, Thomas M Link 1, Peder EZ Larson1,3, and Roland Krug1 1Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States, 2Global MR Applications and Workflow, General Electric, San Diego, CA, United States, 3Joint Graduate Program in Bioengineering, University of California, San Francisco/Berkeley, San Francsico, CA, United States

 336 8:15 Strategies for Obtaining Relaxation Rates due to Chemical Exchange from Parameter Free Atomistic Simulations Henning Henschel1, Matti Hanni1,2, and Miika T. Nieminen1,2 1University of Oulu, Oulu, Finland, 2Oulu University Hospital, Oulu, Finland

 337 8:15 Automatic Segmentation of Hip Cartilage with Deep Convolutional Neural Nets for the evaluation of Acetabulum and Femoral T1ρ and T2 relaxation times. Michael Girard1, Valentina Pedoia2, Berk Norman2, Jasmine Rossi-Devries2, and Sharmila Majumdar2 1Center for Digital Health Innovation, University of California, San Francisco, San Francisco, CA, United States, 2Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States

 338 8:15 Assessment of the clinical feasibility of routine T2 mapping of the intervertebral disc using highly undersampled k-space data Marcus Raudner1, Markus Schreiner1,2, Tom Hilbert3,4,5, Tobias Kober3,4,5, Vladimir Juras6, Claudia Kronnerwetter6, David Stelzeneder2, and Siegfried Trattnig1 1High Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria, 2Department of Orthopaedics, Medical University of Vienna, Vienna, Austria, 3Advanced Clinical Imaging Technology, Siemens Healthcare AG, Lausanne, Switzerland, 4Department of Radiology, University Hospital (CHUV), Lausanne, Switzerland, 5LTS5, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, 6High Field MR Centre of Excellence, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria

 339 8:15 Voxel-wise ratios of amide proton transfer (APT) signals and standardized uptake values (SUVs) of fluorodeoxyglucose (FDG) in the differentiation of myxoid-rich soft-tissue tumors with FDG-PET/MR imaging Koji Sagiyama1, Yuji Watanabe2, Keisuke Ishimatsu1, Takeshi Kamitani1, Yuzo Yamasaki2, Takuya Hino1, Sungtak Hong3, Jochen Keupp4, Yoshihiro Matsumoto5, and Hiroshi Honda1 1Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan, 2Department of Molecular Imaging and Diagnosis, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan, 3Healthcare, Philips Electronics Japan, Tokyo, Japan, 4Philips Research, Hamburg, Germany, 5Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan

 340 8:15 Assessment of early treatment response by multiparametric whole-body MRI as a 1-step approach to prediction of overall response rate in patients with multiple myeloma Miyuki Takasu1, Takayuki Tamura1, Yuji Akiyama1, Yoko Kaichi1, Shota Kondo1, Chihiro Tani1, and Kazuo Awai1 1Department of Diagnostic Radiology, Hiroshima University Hospital, Hiroshima, Japan

 341 8:15 Simultaneous Bilateral Knee MR Imaging Feliks Kogan1, Evan Gregory Levine1, Akshay Chaudhari1, Uchechukwuka D. Monu1, Kevin Epperson1, Edwin Oei2, Garry Gold1, and Brian Hargreaves1 1Radiology, Stanford University, Stanford, CA, United States, 2Radiology, Erasmus MC, Rotterdam, Netherlands

Combined Educational & Scientific Session

### Prostate Cancer: Current Gaps & Future Directions

Organizers: Kathryn Fowler, Kartik Jhaveri, Lorenzo Mannelli, Valeria Panebianco, Scott Reeder, Mustafa Shadi Bashir, Claude Sirlin, Reiko Woodhams

 S02 Tuesday 8:15 - 10:15 Moderators: Daniel Margolis & Alberto Vargas

 8:15 Prostate Cancer: Defining Clinically Significant Disease Peter Choyke1 1National Cancer Institute, United States The goal of performing MRI in prostate cancer is to help distinguish indolent, low risk prostate cancers from those harboring clinically significant features.  This presentation reviews the criteria for clinically significant tumors and underscores the benefits that accrue when using MRI as a gateway for the diagnosis of prostate cancer.

 342 8:45 T2-weighted MRI-derived textural features can help the assessment of peripheral zone prostate cancer aggressiveness: results from multi-center data. Gabriel Nketiah1, Mattijs Elschot1, Tom W Scheenen2, Marnix C Maas2, Tone F Bathen1,3, and Kirsten M Selnæs1,3 1Department of Circulation and Medical Imaging, NTNU, Norwegian University of Science and Technology, Trondheim, Norway, 2Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, Netherlands, 3St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway The assessment of prostate cancer aggressiveness is currently based on Gleason grading of histological samples obtained by TRUS-guided biopsies, which can lead to substantial underestimations due to sampling errors. We previously showed that textural features derived from T2-weighted MRI could potentially serve as a non-invasive biomarker for prostate cancer aggressiveness. The aim of this work was to validate these preliminary results in a multi-center study. We found that the combination of intensity and textural features could distinguish between low/intermediate and high-grade with an accuracy of 71%, which was significantly higher than intensity (60%) or textural features (68%) alone.

 343 8:57 Radiomics measured with mpMRI predicts histopathological and genomics markers of prostate cancer aggressiveness. Stefanie Hectors1, Mathew Cherny2, Sara Lewis1,2, Kanika Mahajan3, Ardeshir Rastinehad3, Ashutosh Tewari3, and Bachir Taouli1,2 1Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 2Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 3Department of Urology, Icahn School of Medicine at Mount Sinai, New York, NY, United States The goal of this study was to assess the association of multiparametric MRI (mpMRI) radiomic features with histopathological and genomic markers of prostate cancer (PCa) aggressiveness. mpMRI histogram and texture features showed multiple significant correlations with Gleason score, modified Gleason score Grade Group and genomics Decipher risk score. General linear models showed high accuracy for prediction of the histopathological and genomics features (accuracy range 0.77-0.94). The results indicate that MRI radiomics analysis is promising for noninvasive assessment of PCa aggressiveness on the histopathological and genomics levels.

 9:09 Current State-Of-The-Art Imaging Protocol: Where Are The Gaps? Masoom Haider1 1Joint Dept of Medical Imaging - MSH, University of Toronto, Canada In Pi-Rads v2 there are technical recommendations for performance of multiparametric MRI (mpMRI) of the prostate. When using this protocol there are several issues that lead to suboptimal or non-diagnostic images that remain unaddressed. Some of these can be mitigated through altering patient preparation or a changing of pulse sequence parameters. Further optimization and development of robust pulse sequences and imaging systems to improve prostate MRI image quality is an unmet need that can benefit from further research. A second critical area in need of further development is related to value which goes hand in hand with cost reduction. This is also tied to the growing and controversial concerns related to repeated Gd administration for DCE MRI and the unknown long-term effects of Gd deposition in the brain in an otherwise healthy patient population with long life expectancy. The necessity of DCE MRI and the potential of proton spectroscopy to replace DCE MRI are other potential areas of innovation.

 344 9:39 Reduced distortion in prostate DWI by using split echo type TSE-DWI (SPLICE) with MultiVane acquisition Yuta Akamine1, Tomoyuki Okuaki1, Satoshi Goshima2, Kimihiro Kajita2, Masatoshi Honda1, Masami Yoneyama1, Makoto Obara1, and Marc Van Cauteren3 1Philips Japan, Shinagawa, Tokyo, Japan, 2Department of Radiology, Gifu University Hospital, Gifu, Japan, 3Philips Healthcare, Shinagawa, Tokyo, Japan To reduce image distortion in prostate DWI, split-echo type TSE-DWI (SPLICE) was combined with MultiVane (current Philips implementation of PROPELLER) acquisition, named MV-SPLICE. To avoid non-CPMG artifacts in SPLICE, the spin echoes and stimulated echoes were separated by the unbalanced readout gradient and acquired in separate MultiVane k-space for separate reconstruction. ADCs and SNRs in transition zone and peripheral zone, and distortion for DWI and T2W images in the anterior-posterior direction of prostate diameter for MV-SPLICE were compared to conventional EPI and MultiVane TSE-DWI (MV-ALSOP). We demonstrated that MV-SPLICE is insensitive to distortion and can provide comparable ADC measurement.

 345 9:51 Accelerated 3D 1 mm isotropic T2w-Imaging of the Prostate in less than 3 min Rohini Vidya Shankar1, Gastao Cruz1, Radhouene Neji2, Elisa Roccia1, René Botnar1, Vicky Goh1,3, Claudia Prieto1, and Isabel Dregely1 1School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom, 2Siemens Healthcare Limited, Frimley, United Kingdom, 3Cancer Imaging, King's College London, London, United Kingdom Three dimensional (3D), isotropic T2-weighted imaging of the prostate requires a long acquisition time. Here we propose a 3D T2-prepared multi-shot bSSFP acquisition with a variable density undersampled trajectory and TV-SENSE reconstruction. Results from a healthy volunteer study demonstrate that 3D 1 mm isotropic resolution T2-weighted images of the prostate can be acquired in 2 min 45 s, with image quality that is comparable to the clinical standard turbo spin echo sequences but only takes 1/3 of the acquisition time.

 346 10:03 Targeted Biopsy Validation of Peripheral Zone Prostate Cancer Characterization with MR Fingerprinting and Diffusion Mapping Ananya Panda1, Gregory O'Connor2, Yun Jiang1, Alice Yu3, Shivani Pahwa4, Sara Dastmalchian4, Seunghee Margevicius5, Mark Schluchter5, Robert Abouassaly6, Chaitra Badve1,2,4, Mark Griswold1,2,4, Lee Ponsky2,7, and Vikas Gulani1,2,4 1Radiology, Case Western Reserve University, Cleveland, OH, United States, 2School of Medicine, Case Western Reserve University, Cleveland, OH, United States, 3Radiology, Johns Hopkins University, Baltimore, MD, United States, 4Radiology, University Hospitals Cleveland Medical Center, Cleveland, OH, United States, 5Biostatistics, Case Western Reserve University, Cleveland, OH, United States, 6Urology, Cleveland Clinic, Cleveland, OH, United States, 7Urology, University Hospitals Cleveland Medical Center, Cleveland, OH, United States Targeted biopsy validation is presented for characterization of peripheral zone (PZ) prostate cancer grades and differentiation of prostate cancer from prostatitis, using a quantitative MR protocol comprising of MRF-relaxometry and standard EPI based ADC mapping. Mean T1, T2 and ADC in prostate cancer were significantly lower than in NPZ. Mean T2 and ADC in low-grade cancer were significantly higher than intermediate and high-grade cancer with similar AUCs (0.80) for both for differentiating grades. Mean T2 and ADC in prostate cancer were significantly lower than prostatitis. T2 was a significant predictor for prostate cancer over prostatitis while ADC was not significant.

 10:15 Adjournment & Meet the Teachers

Combined Educational & Scientific Session

### Studying the Value of MRI

Organizers: Vikas Gulani, James Pipe

 S03 Tuesday 8:15 - 10:15 Moderators: Vikas Gulani & James Pipe

 8:15 Measuring the Value of MRI: Comparative Effectiveness & Outcomes Research Stella Kang1 1NYU Medical Center, United States With growing emphasis on value in health care, there is a need to assess the effects of MRI use on patient health outcomes. The value, or the health outcomes relative to the cost, can be studied using established comparative effectiveness research and outcomes assessment methods. The synthesis of clinical context with test use also allows for analyses of personalized decision making based on test information. The major methods described will include decision analysis, cost effectiveness, and study of intermediate outcomes.  These methods can allow for quantification of population level health benefits, comparison with other tests or interventions, and identification of research priorities based on predicted impact.

 8:37 The Meaning of MR Value to Underserved Populations: Thoughts & Initial Technical Experience Sairam Geethanath1 1Dayanada Sagar College of Engineering, India

 8:49 Questions

 347 8:55 Diagnostic Comparison of Two Rapid Knee MRI Protocols for Comprehensive Whole-Joint Assessment: A Multi-Reader Feasibility Study Akshay S Chaudhari1, Bragi Sveinsson2, Jeff P Wood1, Kathryn J Stevens1, Christopher F Beaulieu1, Edwin H Oei3, Jarrett Rosenberg1, Evan G Levine1, Feliks Kogan1, Marcus T Alley1, Garry E Gold1, and Brian A Hargreaves1 1Radiology, Stanford University, Palo Alto, CA, United States, 2Harvard Medical School, Stanford, MA, United States, 3Radiology & Nuclear Medicine, Erasmus Medical Center, Rotterdam, Netherlands There were approximately 1.25 million clinical knee magnetic resonance imaging (MRI) scans performed in the US annually. Most knee MRI protocols require approximately 30 minutes of scan time. However, there is interest in expedited imaging protocols, especially under the ISMRM Value Initiative. Through a study involving 35 patients and 5 readers, we have demonstrated the feasibility of (1) a single 5-minute DESS sequence and (2) a 5-minute DESS sequence paired with a 2-minute coronal PDFS sequence, as two potential methods for accurate, rapid, and comprehensive diagnostic whole-joint knee MRI.

 348 9:00 How Fast is “Fast MRI” for Breast Cancer Screening? Emily F. Conant1, Arijitt Borthakur1, Mitchell D. Schnall1, and Susan P. Weinstein1 1Department of Radiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States We compare the scan and total study times from a newly implemented abbreviated MR protocol (AP) for breast cancer screening consisting of localizer, T2-STIR, and single pair of pre- and post-contrast 3D T1 sequences to similar times from our full MRI screening protocol.  A retrospective analysis was performed using scan time data obtained from image dicom files as well as data from the Radiology Information System (RIS) for technologist activity times to determine the variance between the two protocols. The results of this study will help guide operational value improvements and estimates for appropriate pricing for the newly implemented AP for breast cancer screening.

 349 9:05 Benefits and Challenges of Spiral MRI in Routine Clinical Brain Imaging: Early Results Melvyn B Ooi1, Zhiqiang Li2, Dinghui Wang2, Ryan K Robison3, Nick R Zwart2, Ashley G Anderson1, Akshay Bakhru4, Tanya Mathews4, Suthambhara Nagaraj4, Silke Hey5, Jos Koonen5, Ad Moerland5, Jonathan Chia1, Ivan Dimitrov1, Harry Friel1, Makoto Obara6, Indrajit Saha7, Yi Wang1, Yansong Zhao1, Harry H Hu8, Amber Pokorney3, Marco Pinho9, Osamu Togao10, Tom Chenevert11, Ashok Srinivasan11, Juan E Small12, Mara M Kunst12, Rakesh Kumar Gupta13, Jalal B Andre14, Nandor K Pinter15, Jeffrey H Miller3, and James G Pipe2 1Philips Healthcare, Gainesville, FL, United States, 2Barrow Neurological Institute, Phoenix, AZ, United States, 3Phoenix Children’s Hospital, Phoenix, AZ, United States, 4Philips Innovation Campus, Bangalore, India, 5Philips Healthcare, Best, Netherlands, 6Philips Healthcare, Tokyo, Japan, 7Philips Healthcare, Gurgaon, India, 8Nationwide Children’s Hospital, Columbus, OH, United States, 9University of Texas Southwestern Medical Center, Dallas, TX, United States, 10Kyushu University Hospital, Fukuoka, Japan, 11University of Michigan, Ann Arbor, MI, United States, 12Lahey Hospital & Medical Center, Burlington, MA, United States, 13Fortis Memorial Research Institute, Gurgaon, India, 14University of Washington, Seattle, WA, United States, 15Dent Neurologic Institute, Amherst, NY, United States Spiral MRI possesses several advantages vs. Cartesian MRI, due to differences in their k-space trajectories and underlying MR physics, which can be leveraged for added value in routine clinical imaging. A Spiral Neuroimaging Cooperative, consisting of nine clinical sites, was formed for the multi-center evaluation of spiral MRI as an alternative to Cartesian MRI in routine clinical imaging. Post-contrast brain spiral 2DT1SE were compared with Cartesian 2DT1SE or TSE. Spirals demonstrated faster scanning with consistent flow artifact reduction vs. both Cartesian options, and superior overall image quality (T1 contrast, lesion visualization) vs. TSE.

 350 9:10 30 brain MRI exams in 1 hour using a multi-contrast EPI sequence Stefan Skare1,2, Tim Sprenger2,3, Ola Norbeck1,2, Henric Rydén1,2, Enrico Avventi1,2, Lars Blomberg1, Johan Berglund1,2, Mikael Skorpil1, Maria Sandell1, and Mathias Engström3 1Department of Neuroradiology, Karolinska University Hospital, Stockholm, Sweden, 2Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden, 3MR Applied Science Laboratory Europe, GE Healthcare, Stockholm, Sweden An in-house developed multi-contrast EPI sequence producing six MR contrasts (T1-FLAIR, T2-w, DWI, ADC, T2*-w, and T2-FLAIR) was used as a fast brain MRI protocol. Seven healthy volunteers were scanned repeatedly to investigate how many brain MRI exams that can be performed over the course of one hour. With a net scan time of one minute and an additional minute for table movements and switch of subjects, it was possible to perform 30 brain MRI examinations in 1 h.

 351 9:15 Rapid Synthetic MRI of the whole brain using simultaneous multi-slice technique Suchandrima Banerjee1, Graeme McKinnon2, and Marcel JB Warntjes3 1Global MR Applications & Workflow, GE Healthcare, Menlo Park, CA, United States, 2Global MR Applications & Workflow, GE Healthcare, Waukesha, WI, United States, 3SyntheticMR, Linköping, Sweden Synthetic MRI enables reconstruction of multiple MRI contrasts from a single scan based on voxel-wise computation of relaxation parameters. This can improvement scan productivity and workflow considerably. The utility of synthetic MRI has recently been demonstrated in clinical settings. However in its current implementation whole brain coverage can be achieved within 5 minutes only if a thick slice prescription (~ 4mm) is used, but this might provide insufficient through-plane resolution for certain clinical protocols and can also lead to partial voluming effects. This work explores the simultaneous multislice approach for more efficient through plane coverage with synthetic MRI.

 352 9:20 Decision Curve Analysis for Prostate Biopsy using MRI with or without Dynamic Contrast Enhancement Vinay Prabhu1, Andrew B. Rosenkrantz1, and Stella K. Kang1 1Radiology, NYU School of Medicine, New York, NY, United States Prostate MRI with dynamic contrast enhancement (DCE) is controversial with growing interest in noncontrast (NC) MRI. Decision curve analyses performed on data from two contemporary studies identified ranges of high grade cancer probability thresholds at which DCE had the highest net benefit. DCE MRI has the most benefit in moderate or moderate-high risk threshold ranges, thought to vary based on the study differences in disease prevalence, reference standard, and the presence or absence of additional DCE reconstruction images. The risk ranges in which NC versus DCE MRI optimize net benefit may help inform the best clinical use of prostate MRI.

 353 9:25 Impact of Routine Magnetic Resonance Imaging on Diagnosis and Treatment of Women with Benign Gynecologic Conditions Seen in a Multidisciplinary Fibroid Center Kim Nhien Vu1, Angela Marie Fast1, Robyn Shaffer2, Deirdre A. Lum3, Berta Chen3, David Hovsepian1, and Pejman Ghanouni1 1Radiology, Stanford University, Stanford, CA, United States, 2Medicine, Stanford University, Stanford, CA, United States, 3Obstetrics & Gynecology, Stanford University, Stanford, CA, United States Pelvic ultrasounds often represent the first and only line of imaging for uterine fibroid evaluation. Our study aims to determine the added value of routine pelvic magnetic resonance imaging (MRI) on diagnosis and treatment of women presenting with symptomatic uterine fibroids. A retrospective review was performed on 569 consecutive women referred to our multidisciplinary fibroid center over a three-year period. Compared to ultrasound alone, MRI affected diagnosis in over a third of patients, which also altered treatment options. These findings justify the use of routine pelvic MRI in women with symptomatic fibroids, particularly those presenting with dysmenorrhea.

 354 9:30 Staging hemodynamic failure: BOLD fMRI cerebrovascular reactivity beats [15O]-H2O-PET. Marco Piccirelli1, Christiaan van Niftrik2, Geoffrey Warnock3, Susanne Wegener4, Athina Pangalu1, Giuseppe Esposito2, Antonios Valavanis1, Alfred Buck5, Andreas Luft4, Oliver Bozinov2, Luca Regli2, and Jorn Fierstra2 1Neuroradiology, University Hospital Zurich, Zurich, Switzerland, 2Neurosurgery, University Hospital Zurich, Zurich, Switzerland, 3Pharmacology & Toxicology, University Hospital Zurich, Zurich, Switzerland, 4Neurology, University Hospital Zurich, Zurich, Switzerland, 5Nuclear Medicine, University Hospital Zurich, Zurich, Switzerland The actual gold standard stroke risk assessment is cerebral blood flow (CBF) measured with [15O]-H2O-PET, which is available only in few specialized centers and requires ~1mSv radioactive dose. Otherwise, quantitative CVR measurements derived (with our temporal decomposition iterative algorithm) from Blood-Oxygen-Level-Dependent (BOLD) fMRI with CO2 challenge might apply as a surrogate imaging-marker for hemodynamic failure, as the <7 minutes acquisition can easily be clinically implemented, and has – as proved in this study – twice higher specificity*sensitivity for staging hemodynamic failure in chronic cerebrovascular steno-occlusive diseases than PET. Therefore, BOLD CVR shall be widely implemented for assessing stroke risk.

 355 9:35 A solar powered MR spectrometer system Martyn Paley1,2 1MRI, ISD Ltd, Bradley, United Kingdom, 2Academic Radiology, University of Sheffield, Sheffield, United Kingdom Most MRI systems have very high electrical power consumption and require extensive cryogenic support systems. A spectrometer design has been developed for a low cost, low weight and low power specialised MR system capable of ‘unplugged’ operation for worldwide use in remote locations.

 356 9:40 REconstruction of MR images acquired in highly inhOmogeneous fields using DEep Learning (REMODEL) Punith B Venkate Gowda1, Asha K Kumara Swamy1, Sachin Jambawalikar2, Sairam Geethanath1,2, and Thomas Vaughan2 1Medical Imaging Research Centre, Dayananda Sagar College of Engineering, Bangalore, India, 2Dept. of Radiology, Columbia University Medical Center, New York, NY, United States The aim of this study was to develop and demonstrate a supervised learning algorithm to reconstruct MR images acquired in highly in-homogeneous magnetic fields. Brain images were used to train a deep neural network. This was performed for image sizes of 32 x 32 and 64 x 64. Results obtained demonstrate REMODEL’s ability to reconstruct the images obtained in in-homogeneous magnetic fields of up to ±50 kHz with high fidelity. The root-mean-square-error for these reconstructions compared to the uncorrupted ground truth was lesser than 0.15 and significantly lesser than the corrupted images.

 357 9:45 Creating Standardized MR Images with Deep Learning to Improve Cross-Vendor Comparability Enhao Gong1, John Pauly1, and Greg Zaharchuk2 1Electrical Engineering, Stanford University, Stanford, CA, United States, 2Radiology, Stanford University, Stanford, CA, United States A very common task for radiologists is to compare sequential imaging studies that were acquired on different MR hardware systems, which can be difficult and inaccurate because of different designs across scanners and vendors. Cross-vendor standardization and transformation is valuable for more quantitative analysis in clinical exams and trials. With in-vivo multi-vendor datasets, we show that it is possible to achieve accurate cross-vendor transformation using the state-of-art Deep Learning Style-transfer algorithm. The method preserves anatomical information while transferring the vendor specific contrast "style". The usage of unsupervised training enable the method to further train and apply on all existing large scale MRI datasets. This technique can lead to a universal MRI style which benefits patients by improving inter-subject reproducibility, enabling quantifiable comparison and pushing MRI to be more quantitative and standardized.

 9:50 Panel Discussion

 10:15 Adjournment & Meet the Teachers

Oral

### Cardiac Function & Myocardial Perfusion

 N01 Tuesday 8:15 - 10:15 Moderators: Bettina Baessler & Krishna Nayak

 358 8:15 Improved 2D cardiac Cine MRI with retrospective gating using Golden-angle Radial acquisition and Angle-Based echo-Sharing (GRABS) Qi Liu1, Yu Ding1, Jingyuan Lyu1, Lele Zhao2, Yanqun Teng2, and Jian Xu1 1UIH America, Inc., Houston, TX, United States, 2United Imaging Healthcare, Shanghai, China Cardiac Cine MRI with retrospective gating using Golden-angle Radial acquisition and Angle-Based echo-Sharing is a promising technique permitting retrospective gating, arbitrary temporal resolution, and arrhythmia data rejection. It is an easy-to-implement and effective technique that features improved image quality by reducing streaking artifacts.

 359 8:27 Feasibility of Ultra-high Simultaneous Multi-slice and In-plane Accelerations for Cardiac MRI Using Outer Volume Suppression and Leakage-Blocking Reconstruction Sebastian Weingärtner1,2,3, Steen Moeller2, and Mehmet Akcakaya1,2 1Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN, United States, 2Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States, 3Computer Assisted Clincial Medicine, University of Minnesota, Mannheim, Germany Simultaneous multi-slice (SMS) imaging has gained increasing interest for enabling high scan-time acceleration at the cost of minimal loss in SNR. However, its applications in cardiac MRI have been limited, as the feasible acceleration is restricted by unfavorable coil geometry. In this study, we investigate the use of outer-volume suppression (OVS) in combination with CAIPIRINHA to promote dissimilarities among the multi-bands. We propose a time and SAR efficient multi-band scheme for OVS and apply these techniques with a leakage blocking reconstruction to increase the feasible acceleration in cardiac cine and perfusion imaging. Combining these techniques, we achieve clinical image quality with 5 fold SMS acceleration in Cine and 16-fold spatial-only acceleration in perfusion MRI.

 360 8:39 Feasibility of absolute myocardial blood flow quantification using Simultaneous Multi Slice (SMS) SSFP first-pass myocardial perfusion imaging and iterative reconstruction at 1.5 Tesla. Muhummad Sohaib Nazir1, Radhouene Neji1,2, Peter Speier3, Daniel Staeb4, Michaela Schmidt3, Christoph Forman3, Reza Razavi1, Sven Plein1, Tevfik Ismail1, Sebastien Roujol1, and Amedeo Chiribiri1 1Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom, 2MR Research Collaborations, Siemens Healthcare Limited, Frimley, United Kingdom, 3Siemens Healthcare, Erlangen, Germany, 4The Centre for Advanced Imaging, The University of Queensland, Brisbane, Australia Quantification of myocardial blood flow (MBF) enhances diagnosis and provides prognostic information. Simultaneous Multi Slice (SMS) imaging allows greater spatial coverage of the heart with minimal signal-to-noise penalty and is thus desirable for perfusion imaging. 5 patients underwent two rest perfusion scans using a dual-bolus technique with SMS protocol (6 slices) and iterative reconstruction and standard 3 slice bSSFP sequence. Absolute MBF was quantified with a fermi-constrained deconvolution algorithm. Global and territorial MBF was comparable between the different methods. Future evaluation in patients with stress testing and greater heart coverage may provide clinical utility in patients with coronary artery disease.

 361 8:51 Improving compressed sensing reconstructions for myocardial perfusion imaging with residual artifact learning Ganesh Adluru1, Bradley D. Bolster, Jr.2, Edward DiBella1, and Brent Wilson3 1Radiology & Imaging Sciences, University of Utah, Salt lake city, UT, United States, 2US MR R&D Collaborations, Siemens Healthineers, Salt Lake City, UT, United States, 3Cardiology, University of Utah, Salt Lake City, UT, United States Compressed sensing/constrained reconstruction methods have been successfully applied to myocardial perfusion imaging for improving in-plane resolution and improving slice coverage without losing temporal resolution.  However at high acceleration factors and in the presence of large inter-time frame motion image quality from the CS methods is affected.  Here we propose an artifact learning neural network that aims to improve the image quality of spatio-temporal constrained reconstruction methods for gated Cartesian and ungated radial data.  Promising results are shown on datasets that were not used in training the neural network.

 362 9:03 Beat-by-Beat Dynamic Assessment of Myocardial Oxygenation with Highly Time-Resolved, Free-breathing, Ungated Cardiac T2 BOLD MRI Using a Low-Rank Tensor Formulation Hsin-Jung Yang1, Anthony G. Christodoulou1, Jane Sykes2, Xiaoming Bi3, Ivan Cokic4, Frank S Prato2, Debiao Li4, and Rohan Dharmakumar4 1Biomedical Imaging Research Institute, Cedars Sinai Medical Center, Los Angeles, CA, United States, 2Lawson Research Institute, London, Canada, 3Siemens Healthineers, Los Angeles, CA, United States, 4Cedars Sinai Medical Center, Los Angeles, CA, United States Coronary vasodilation and the ensuing myocardial hyperemia following the administration of a provocative stressor is a dynamic process. However, established perfusion methods are confounded by contrast accumulation and lack the temporal resolution to accurately evaluate the process.   BOLD CMR is an emerging method for monitoring myocardial perfusion without contrast agents, but the current methods are slow. We developed a non-ECG-gated, free breathing, beat-to-beat, cardiac/respiratory phase-resolved, T2-based BOLD CMR sequence at 3T using a low rank tensor framework to enable highly time-resolved assessment of coronary reactivity. We tested the proposed technique in an animal model with and without coronary disease.

 363 9:15 Non-invasive pressure-volume loops from cardiovascular magnetic resonance and brachial pressure Felicia Seemann1,2, Per Arvidsson1, David Nordlund1, Sascha Kopic1, Marcus Carlsson1, Håkan Arheden1, and Einar Heiberg1,2 1Department of Clinical Physiology, Skåne University Hospital, Lund University, Lund, Sweden, 2Department of Biomedical Engineering, Faculty of Engineering, Lund University, Lund, Sweden Cardiac pressure-volume loop analysis provides important information on cardiac function, but is currently not widely utilized clinically since invasive measurements are required. This study aimed to develop and validate a non-invasive method of estimating pressure-volume loops, via a model-based framework using cardiovascular magnetic resonance. The method yields individualized pressure-volume loops computed using time-varying elastance, with left ventricular volume and brachial pressure as input. Experimental validation showed strong agreement to in-vivo measurements, and application to healthy controls and heart failure patients yielded expected results. Hence, the model is a promising method for obtaining pressure-volume loops from magnetic resonance imaging.

 364 9:27 Subtle changes in hyperelastic properties of myocardium with cardiotoxicity remodeling from CMR Delphine Perie-Curnier1, Marianna Gamba1, Marilou Trempe1, Jenny Wang2, Martyn Nash2, Alistair Young3, and Daniel Curnier4 1Mechanical Engineering, Polytechnique Montreal, Montreal, QC, Canada, 2Biomedical Engineering, University of Auckland, Auckland, New Zealand, 3Anatomy with Radiology, University of Auckland, Auckland, New Zealand, 4Kinesiology, University of Montreal, Montreal, QC, Canada The aim of this study was to assess subtle changes in 3D geometrical and mechanical properties of left ventricle in childhood acute lymphoblastic leukemia survivors. Global 3D volume or ejection fraction were not sensitive enough while time dependent 3D geometrical parameters over the cardiac cycle showed that early diastole is more affected than systole or late diastole. Smaller hyper-elastic properties were found in the high risk group than in the standard risk, high risk with cardioprotective agent or healthy volunteers group. High temporal resolution and local parameters would improve the detection of these subtle changes.

 365 9:39 Self-gated free-breathing cine DENSE imaging by adaptively reducing residual T1-echo energy Xiaoying Cai1 and Frederick H Epstein1,2 1Biomedical Engineering, University of Virginia, Charlottesville, VA, United States, 2Radiology, University of Virginia, Charlottesville, VA, United States Cine DENSE is a well-established myocardial strain imaging technique that typically requires breath-holding. In this study, we developed a self-gated free-breathing adaptive acquisition algorithm that reduces free-breathing artifacts by minimizing the residual energy of the phase-cycled T1-relaxation signal. The algorithm adaptively repeats the acquisition of the k-space data with the highest residual T1-echo energy. Evaluation in 7 healthy subjects demonstrated that the method provides high quality free-breathing self-gated cine DENSE images in a clinically-reasonable scan time.

 366 9:51 Assessment of Regional Myocardial Velocities by Tissue Phase Mapping and Feature Tracking in Healthy Children and Pediatric Patients with Hypertrophic Cardiomyopathy: A Comparison Study Alexander Ruh1, Arleen Li2, Joshua D Robinson1,3,4, Cynthia K Rigsby1,4,5, and Michael Markl1,6 1Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States, 2Feinberg School of Medicine, Northwestern University, Chicago, IL, United States, 3Department of Pediatrics, Division of Pediatric Cardiology, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, United States, 4Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States, 5Department of Medical Imaging, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, United States, 6Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Chicago, IL, United States In this study, we compare tissue phase mapping (TPM) and feature tracking (FT) of standard cine SSFP images for the assessment of regional myocardial velocities in 15 pediatric patients with hypertrophic cardiomyopathy (HCM) and 20 age-matched healthy controls. Data analysis included the calculation of segmental (AHA 16-segment model) left ventricular radial and long-axis peak velocities in systole and diastole. Both techniques detected significantly decreased diastolic velocities in HCM patients compared to controls, suggesting reduced myocardial relaxation despite normal ejection fraction. Lower temporal resolution of FT derived velocities resulted in systematically lower peak velocities compared to directly measured TPM velocities.

 367 10:03 Cardiac Single Breath-hold Balanced SSFP Cine ‘Watermark’ provides Cardiac Function via Magnitude and 2D Myocardial Strain via Phase Ronald J. Beyers1, Nouha Salibi1,2, and Thomas S. Denney1 1MRI Research Center, Auburn University, Auburn, AL, United States, 2Siemens Healthineers, Malvern, PA, United States Cardiac MRI myocardial tagging enables quantification of myocardial strain.  However, tagging remains limited to a research context due to the time-intensive analysis and need to run multiple sequences.  CMR sequences must be fast and efficient.  We previously developed a FLASH-based cine sequence called Cine ‘Watermark’ (CWM) that acquires normal cine magnitude images plus ‘hidden’ (via phase) cardiac strain data for calculating myocardial strain. Here we present a Balanced SSFP (bSSFP) version of CWM that presents improved SNR and scan efficiency.  The bSSFP CWM is demonstrated in human subjects at 3T and its performance is compared to conventional Grid-Tagging MRI.

Oral

### Application of Neurovascular Methods

 N02 Tuesday 8:15 - 10:15 Moderators: Luis Hernandez-Garcia & Seong-Gi Kim

 368 8:15 Unraveling Cardiac and Respiratory Contributions to Brain Tissue Motion using Single Shot 2D DENSE at 7T MRI. Jacob Jan Sloots1, Ayodeji L. Adams1, Peter R. Luijten1, Geert Jan Biessels2, and Jaco J. M. Zwanenburg1 1Radiology, University Medical Center Utrecht, Utrecht, Netherlands, 2Neurology, University Medical Center Utrecht, Utrecht, Netherlands The cardiac cycle and respiration both influence CSF dynamics and therefore the displacement of brain tissue. In this work we unravel their contribution to brain tissue displacement using a single shot 2D cine displacement-encoded imaging method employing stimulated echoes (DENSE) for brain motion measurements. Displacement-encoded data sets in the Feet-to-Head direction of seven volunteers were fitted to a linear model. Consistent trends in displacements were observed. The developed DENSE sequence results showed similar sized contributions to brain tissue displacement. Relating these displacements to contributions to the clearance system remains future work.

 369 8:27 Macromolecular proton fraction closely correlates with myelin loss in the rat ischemic stroke model Alena A Kisel1, Marina Yu Khodanovich1, Dmitriy N Atochin1,2, Andrey E Akulov1,3, Lilia R Mustafina4, Anna V Naumova1,5, and Vasily L Yarnykh1,5 1Research Institute of Biology and Biophysics, Tomsk State University, Tomsk, Russian Federation, 2Massachusetts General Hospital, Charlestown, MA, United States, 3Institute of Cytology and Genetics SB RAS, Novosibirsk, Russian Federation, 4Siberian State Medical University, Tomsk, Russian Federation, 5Department of Radiology, University of Washington, Seattle, WA, United States Non-invasive quantitative assessment of myelin damage in ischemic stroke is currently unavailable. The goal of this study was to evaluate a recently proposed myelin imaging technique, macromolecular proton fraction (MPF) mapping in the rat stroke model and compare it with histological myelin quantitation. MPF decrease in the brain infarct closely correlated (R = 0.81, p<0.001) with luxol fast blue staining on the 1st, 3rd, and 10th day after stroke.  Further improvement in accuracy of myelin quantitation (R = 0.98) was achieved with the use of bivariate linear regression model including T2 to correct errors related to edema.

 370 8:39 The effect of breath-hold on cardiovascular pulse in the brain - a multimodal MREG study. Lauri Raitamaa1, Viola Borchardt1, Niko Huotari1, Heta Helakari1, Janne Kananen1, Vesa Korhonen1, and Vesa Kiviniemi1 1OFNI/Radiology, Oulu University Hospital, Oulu, Finland MREG enables critical sampling of human brain physiology. This study reveals novel pulsation changes during repeated breatholds of 32 seconds. Cardiorespiratory control centers in the brain stem show increased pulsation amplitude during the end of the breathold. Also the overall cardiac pulse propagation in the brain alters markedly by breathold, especially when repeated. The findigs show that the MREG data enables spatially accurate estimation of the status of the cardiovascular pulsation which is the primary driver of glymphatic brain clearance.

 371 8:51 ASL imaging and 31P/1H-MRS during prolonged breath-hold among experienced freedivers: Insights into cerebrovascular and metabolic responses Vera Catharina Keil1, Henri Jan Mutsaerts2,3,4, Lars Eichhorn5, Frank Träber1, Wolfgang Block1, Burkhard Mädler6, Kim van de Ven7, Jeroen C. Siero2,8, Bradley J. MacIntosh3, Jan Petr9, Hans H. Schild1, and Elke Hattingen1 1Department of Radiology, University Hospital Bonn, Bonn, Germany, 2Department of Radiology, University Medical Center Utrecht, Utrecht, Netherlands, 3Sunnybrook Research Institute, University of Toronto, Toronto, ON, Canada, 4Radiology Department, Amsterdam Medical Center, Amsterdam, Netherlands, 5Department of Anesthesiology, University Hospital Bonn, Bonn, Germany, 6Philips Healthcare, Bonn, Germany, 7Philips Healthcare, Best, Netherlands, 8Spinoza Centre for Neuroimaging, Amsterdam, Netherlands, 9Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany This pCASL and 31P/1H-MRS study explored the cerebrovascular reactivity (CVR) and its efficacy on brain metabolic stability during a five-minute breath-hold in fifteen experienced freedivers. Cerebral blood flow (CBF) increase occurred later than the decrease of the recently discovered arterial transit time correlate, spatial CoV. The latter may thus be an early CVR biomarker. CBF varied between vessel territories, gray and white matter and usually lowered with more experience. MRS showed near stable physiological cerebral pCr, ATP and pH concentrations despite peripheral lactate acidosis. In conclusion, this trial revealed that CVR sufficiently compensates the metabolic challenge of a five minute breath-hold. In conclusion, this trial revealed that cerebral perfusion increase sufficiently compensates the metabolic challenge of a five-minute breath-hold.

 372 9:03 Sensitivity and specificity of cerebrovascular reactivity in predicting surgical decisions in Moyamoya patients Peiying Liu1, Babu G Welch2, Binu P Thomas2, Yang Li1, Marco C Pinho2, Judy Huang1, and Hanzhang Lu1 1Johns Hopkins University School of Medicine, Baltimore, MD, United States, 2University of Texas Southwestern Medical Center, Dallas, TX, United States Moyamoya disease (MMD) is characterized by chronic occlusion of the distal intracranial internal carotid arteries and can be treated by revascularization surgery. At present, surgical decisions are primarily based on symptomatology and imaging studies such as DSA and SPECT. However, current procedures are costly, invasive, and qualitative. Here we applied a novel iVas-MRI technique that provides quantitative assessment of multiple hemodynamic parameters in a single scan of 9 minutes, and examined its sensitivity and specificity in predicting surgical decisions. Our results showed that iVas-MRI has an overall accuracy of 0.93 in predicting surgical decisions in MMD.

 373 9:15 Baseline Risk Factors Suggestive of Advanced Vascular Disease Predict Differences in Brain CBF Changes After Carotid Revascularization Surgery Salil Soman1, Kyuwon Lee2, Weiying Dai3, Elizabeth Hitchner4, Michael Moseley4, Greg Zaharchuk4, Allyson Rosen4, and Wei Zhou5 1HMS / BIDMC, Boston, MA, United States, 2TUFTS Medical School, Boston, MA, United States, 3SUNY Binghamton, Binghamton, NY, United States, 4Stanford School of Medicine, Stanford, CA, United States, 5University of Arizona, Tucson, AZ, United States Carotid stenosis is a risk factor for stroke. A number of risk factors are associated with stroke. Our work shows specific risk factors that predict differences in brain perfusion using ASL MRI technique after carotid revascularization surgery. Specifically elevated systolic blood pressure, chronic renal insufficiency, and history of prior stroke have mpacts on initial baseline to immediately post surgery prefusion increase, and baseline elevated cholesterol and body mass index show differences in 1 day to 6 months post operation. This is in contrast to hypertension, smoking  and diabetes, which did not show significant predict relationships. Our work suggests that these risk factors may be more closely related to cerebrovascular dysfunction.

 374 9:27 Clinical Feasibility Study of an Accelerated 3D Intracranial Magnetic Resonance Angiography Using Compressed-Sensing Algorithm Zhiyong Lin1, Xiaodong Zhang1, Ke Wang1, Yuan Jiang1, Xiaoyu Hu1, Yong Huang1, Shuai Ma1, Yi Liu1, Lina Zhu1, Zhizheng Zhuo2, Jing Liu1, and Xiaoying Wang1 1Department of Radiology, Peking University First Hospital, Beijing, China, 2Philips Healthcare, Beijing, China Accelerated 3D intracranial magnetic resonance angiography(MRA) using Compressed-Sensing algorithm could be clinically valuable not only for improving the image quality and having almost the same diagnostic performance compared to conventional intracranial MRA, but also for reducing the scanning time which could improve the overall workflow of MRA imaging. It is a feasible protocol in intracranial MRA imaging.

 375 9:39 Multiscale multimodal imaging of the mouse cerebral vascular architecture. Rukun Hinz1, Jan R Detrez2, Lore Peeters1, Caroline Berghmans3, Marleen Verhoye1, Annemie Van der Linden1, Winnok H De Vos2, and Georgios A Keliris1 1Bio-imaging Lab, University of Antwerp, Wilrijk, Belgium, 2Laboratory of Cell Biology and Histology, University of Antwerp, Wilrijk, Belgium, 3Molecular Imaging Center Antwerp, University of Antwerp, Wilrijk, Belgium We present a multiscale multimodal atlas of the mouse cerebral vasculature co-registered to the Allen Brain atlas space. To this end, we combined MRI anatomical imaging with the macro vasculature detected with TOF-MRA as well as the micro vasculature acquired from 3D microscopic imaging of a cleared mouse brain. To achieve a better homogeneity, we used a double labeling of the vasculature using isolectin to stain the vascular wall combined with an albumin staining of the blood vessel lumen. The atlas provides a reference space across multiple imaging modalities and a link to other functional, anatomical and genetic information.

 376 9:51 Hybrid Vessel Centerline Tracking: Towards Automated Lesion Analysis on 3D Intracranial Vessel Wall MR Feng Shi1, Wenhao Xu1,2, Haili Wu1,3, Zixiao Tian1, Qi Yang1,4, Debiao Li1, and Zhaoyang Fan1 1Cedars Sinai Medical Center, Los Angeles, CA, United States, 2Tsinghua University, Beijing, China, 3Beihang University, Beijing, China, 4Xuanwu Hospital, Beijing, China We proposed a hybrid vessel centerline tracking method on 3D intracranial vessel wall MR. TOF MRA was used as a complementary modality that provides additional information for potential vessel path extraction. Results show high agreement of results from the proposed method and manual rater.

 377 10:03 Three Dimensional Intra- and Extra-cranial Arterial Vessel Wall Joint Imaging in Patients with ischemic stroke Na Zhang1, Lin Jia2, Jinhao Lyu3, Lei Zhang1, Wenxiao Jia2, Hairong Zheng1, and Xin Liu1 1Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, shenzhen, China, 2XinJiang Medical University, Urumchi, China, 3Department of Radiology, Chinese PLA General Hospital, Beijing, China Intracranial and carotid atherosclerotic plaques are responsible for about 75% of ischemic stroke, the leading cause of mortality and morbidity worldwide. A 3D intra- and extra-cranial arterial vessel wall joint imaging was developed for simultaneously evaluating intracranial and carotid arterial plaques. The aim of this study was to assess the clinical potential of the 3D joint imaging technique in a large-scale patients with recent cerebrovascular symptoms. In general, this joint imaging method allows satisfactory image quality and comprehensive evaluation of atherosclerotic disease, and it has great potential to be used for optimizing treatment.

Oral

### Signal Encoding & Decoding

 N03 Tuesday 8:15 - 10:15 Moderators: Daniel Gallichan & Jana Hutter

 378 8:15 Chirp-Encoded 3D GRE and MPRAGE sequences Kamlesh Pawar1,2, Zhaolin Chen1,3, Jingxin Zhang3,4, N Jon Shah1,5, and Gary F Egan1,2 1Monash Biomedical Imaging, Monash University, Melbourne, Australia, 2School of Psychological Sciences, Monash University, Melbourne, Australia, 3Department of Electrical and Computer System Engineering, Monash University, Melbourne, Australia, 4School of Software and Electrical Engineering, Swinburne University of Technology, Melbourne, Australia, 5Institute of Medicine, Research Centre Juelich, Juelich, Germany Non-Fourier encoding such as random, noiselets and chirp encoding have demonstrated image quality improvement in accelerated compressive sensing (CS) MRI applications. However, implementation of the non-Fourier encoding schemes in 2D spin echo sequence limits its use in practice, due to the fact that spin echo is inherently a slow sequence. In this work, we present a novel implementation of chirp encoding in fast 3D gradient echo (GRE) and MPRAGE sequences. The chirp encoding scheme is compared with conventional Fourier encoding for compressive sensing and susceptibility weighted imaging applications. The evaluation demonstrates that chirp encoding is able to preserve spatial resolution better than the Fourier encoding.

 379 8:27 Three Vencs for the Price of Two: Efficient Multi-Venc Phase-Contrast MRI for Improved Velocity Dynamic Range Liliana Ma1,2, Kelvin Chow1,3, Can Wu4, Alireza Vali1, Michael Markl1,2, and Susanne Schnell1 1Department of Radiology, Northwestern University, Chicago, IL, United States, 2Department of Biomedical Engineering, Northwestern University, Evanston, IL, United States, 3Cardiovascular MR R&D, Siemens Medical Solutions USA, Inc., Chicago, IL, United States, 4Philips Healthcare, Gainesville, FL, United States Single-venc 4D flow MRI is inherently limited by the need to set a velocity encoding sensitivity (venc), where velocity(v)>venc results in velocity aliasing and v<

 380 8:39 Single-scan multi-spin-echo SPEN for dynamic T2 mapping and for 3D T2 weighted anatomical imaging Qingjia Bao1, Eddy Solomon1, Gilad Liberman1, Samuel Cousin1, and Lucio Fydman1 1Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel SPatiotemporal ENcoding (SPEN) provides single-shot 2D images free from T2* effects, and with enhanced robustness to field distortions. SPEN’s acquisition module is relatively short, opening the possibility to combine SPEN with a multi-spin-echo protocol, thus collecting several images in one shot. This work explores this possibility towards two different aims: the single-shot characterization of spatially-resolved T2 maps, and the accelerated acquisition of 3D images incorporating a phase encoding.  Both approaches proved successful, as exemplified with real-time T2 mapping of in vivo kidney on a perfused mouse and high resolution volumetric acquisitions on ex vivo phantoms and human volunteers.

 381 8:51 Fast imaging with ultrahigh