An Update on Pulse Sequences & Hardware for Body MRI
Shahid M Hussain, MD, PhD, FACR1

1Vice-Chair of Education and Professor of Radiology, Stony Brook University Medical Center, Stony Brook, NY

Synopsis

This presentation will provide an update on pulse sequences and hardware for body MRI. This presentation is by no means a complete overview of the new hardware and pulse sequence development; due to the time constraints, this talk will highlight a few important developments pertinent to body MRI.

This presentation will provide an update on pulse sequences and hardware for body MRI. This presentation is by no means a complete overview of the new hardware and pulse sequence development; due to the time constraints, this talk will highlight a few important developments. I encourage you to contact your specific vendor if you need are looking for a more in-depth information.

This talk will discuss the role of the increasing magnet strength, going from 1.5T to 3.0T and now body MRI appears to have a new frontier with 7.0T. Main challenges to perform routine body MRI at 7.0T are similar to the implementation of 3.0T, which we encountered during the past decade. Currently, most centers consider 3.0T as a standard magnet for body MRI; in fact, many radiologists prefer 3.0T to 1.5T because of its ability to provide improved image quality resulting from a higher signal-to-noise (SNR) ratio. Major hurdles in the implementation of 3.0T for body MRI included the B1 field inhomogeneities largely related to the standing wave and dielectric artifacts, and higher specific absorption (SAR) deposition. The vendors have introduced solutions such as parallel transmission and improved shimming that have addressed the B1 as well as SAR issues. Similar solutions could be applied to improve body MR imaging at 7.0T. Additionally, at 7.0T, the introduction of newer coils with more elements, combined transmit and receive coils, hybrid parallel imaging techniques with larger acceleration factors, compressed sensing, and newer sequences will be important for body MRI.

The purpose of this presentation is

  • To provide an update on pulse sequences and hardware for body MRI.
  • To describe the recent technical and pulse sequence improvements at 3.0T and relate these to 7.0T as the new frontier in body MRI.
  • To provide a glimpse of the future with possible future directions.

Acknowledgements

Thomas G.Perkins, PhD

References

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Proc. Intl. Soc. Mag. Reson. Med. 25 (2017)