Water/fat separated Prostate Diffusion-Weighted Imaging using Dixon-encoded multi-shot EPI with structured low-rank reconstruction

Motivation: Conventional single-shot EPI (ssh-EPI) is fast, but often causes geometric distortions, especially near the rectum. Goal(s): In this research, a Dixon-msh-EPI technique is validated for prostate Diffusion-weighted Imaging (DWI). Approach: Dixon-msh-EPI is proposed to reduce such distortions, while jointly separating water/fat components by a special structured low-rank reconstruction that also corrects shot-to-shot phase variations. Results: Experiments were conducted on 7 healthy male volunteers using a 3T scanner comparing DW-ssh-EPI and Dixon-msh-EPI performance. The Dixon-msh showed significantly reduced geometric distortion and effective fat signal suppression, as scored by two readers. While both methods provided comparable image quality, Dixon-msh-EPI demonstrated improved motion-correction and geometric accuracy. Impact: Dixon-msh-EPI offers improved prostate DWI by significantly reducing geometric distortions and enhancing across b-value registration. This technique could lead to more accurate diagnoses and has the potential to refine clinical MRI protocols, emphasizing precision in prostate diffusion imaging.