Field Strength Dependency of Geometric Distortion in Diffusion-Weighted single-shot EPI: Comparing 0.6 T and 1.5 T Scanners

Motivation: Diffusion-weighted imaging using single-shot EPI (ss-EPI) often suffers from susceptibility-induced distortions, increasing at higher field strengths. This study explores the benefits of 0.6T MRI in minimizing these distortions. Goal(s): To validate ss-EPI DWI at 0.6T in reducing geometric distortions in prostate, abdomen, lower back, and brain, comparing with 1.5T in selected anatomies. Approach: Six volunteers were scanned on a prototype 0.6T system to assess geometric distortion in ss-EPI DWI, with comparative imaging at 1.5T in brain and lower back. Results: At 0.6T, ss-EPI DWI showed reduced distortions around air-tissue interfaces across anatomies, with improved anatomical detail. Impact: 0.6T ss-EPI DWI offers distortion-free imaging in anatomies prone to artifacts at higher fields, such as the prostate, brain, and spine. This approach could enhance diagnostic accuracy, improve patient comfort, and support broader clinical adoption of midfield MRI.