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Title: Real-time MRI of the moving wrist at 0.55 tesla
Objectives:Magnetic resonance imaging (MRI) using 1.5T or 3.0T systems is routinely employed for assessing wrist pathology; however, due to off-resonance artifacts and high power deposition, these high-field systems have drawbacks for real-time (RT) imaging of the moving wrist. Recently, high-performance 0.55T MRI systems have become available. In this proof-of-concept study, we tested the hypothesis that RT-MRI during continuous, active, and uninterrupted wrist motion is feasible with a high-performance 0.55T system at temporal resolutions below 100 ms and that the resulting images provide visualization of tissues commonly interrogated for assessing dynamic wrist instability. Methods:Participants were scanned during uninterrupted wrist radial-ulnar deviation and clenched fist maneuvers. Resulting images (nominal temporal resolution of 12.7–164.6 ms per image) were assessed for image quality. Feasibility of static MRI to supplement RT-MRI acquisition was also tested. Results:The RT images with temporal resolutions < 100 ms demonstrated low distortion and image artifacts, and higher reader assessment scores. Static MRI scans showed the ability to assess anatomical structures of interest in the wrist. Conclusion:RT-MRI of the wrist at a high temporal resolution, coupled with static MRI, is feasible with a high-performance 0.55T system, and may enable improved assessment of wrist dynamic dysfunction and instability. Advances in knowledge:Real-time MRI of the moving wrist is feasible with high-performance 0.55T and may improve the evaluation of dynamic dysfunction of the wrist.  more » « less
Award ID(s):
1828736
PAR ID:
10572554
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
The British Journal of Radiology
Volume:
96
Issue:
1151
ISSN:
0007-1285
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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