Adrienne Campbell-Washburn1
1Cardiovascular Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, United States
Synopsis
Contemporary high-performance low and mid field MRI systems offer new clinical opportunities for MRI. These opportunities include increased accessibility, point-of-care imaging, new applications that are better suited for fields (eg. pulmonary imaging, MRI-guided interventions). When paired with advanced image acquisition and reconstruction methods, high quality images can be achieved using these systems. This talk will describe new clinical opportunities and new imaging methods for low field MRI systems, with a particular focus on high-performance 0.55T systems.
Syllabus
Contemporary low field MRI systems perform well and can offer advantages compared to clinical field strengths [1-5]. These systems are inherently lower cost, thereby potentially increasing accessibility, and offer new clinical opportunities. Some specific clinical applications include portable MRI, point-of-care imaging, safer MRI-guided interventions, improved implant imaging, and improved imaging of anatomy in high-susceptibility regions (eg. lung, bowel, cranial sinuses, airway).
Although low field MRI system have been available since the inception of MRI, they have historically been limited by lower performance hardware. Recently, “high-performance low-field” MRI systems have offered the combination of contemporary hardware and advanced imaging methods at a lower field strength.
Physical properties differ at lower field strengths. For example, T1 is shorter, T2 is longer, T2* is much longer, B0 and B1 fields tend to be more uniform (depending on system design), and SAR is lower. These physical properties leveraged to modify imaging methods to improve SNR-efficiency (eg. SNR-efficient spiral scanning, or traditionally high-SAR methods). Moreover, modern imaging and processing methods can be used to compensate for the lower SNR at lower field, such as constrained reconstructions, AI reconstruction, denoising and MR fingerprinting.
This talk will first describe some of the opportunities of low field MRI, in general. Then, the talk will focus on recent work using high-performance 0.55T MRI systems. This includes pulmonary imaging, MRI-guided interventions, abdominal imaging, cardiac imaging, MR fingerprinting, and new imaging methods. Acknowledgements
No acknowledgement found.References
- Campbell-Washburn, A.E., et al., Opportunities in Interventional and Diagnostic Imaging by Using High-performance Low-Field-Strength MRI. Radiology, 2019: p. 190452.
- Marques, J.P., F.F.J. Simonis, and A.G. Webb, Low-field MRI: An MR physics perspective. J Magn Reson Imaging, 2019. 49(6): p. 1528-1542.
- Sarracanie, M., et al., Low-Cost High-Performance MRI. Sci Rep, 2015. 5: p. 15177.
- Simonetti, O.P. and R. Ahmad, Low-Field Cardiac Magnetic Resonance Imaging: A Compelling Case for Cardiac Magnetic Resonance's Future. Circ Cardiovasc Imaging, 2017. 10(6).
- Wald, L.L., et al., Low-cost and portable MRI. J Magn Reson Imaging, 2020. 52(3): p. 686-696.