SuperRes-EPTI: in-vivo mesoscale distortion-free dMRI at 500μm-isotropic resolution using short-TE EPTI with rotating-view super resolution

To achieve high spatial resolution in-vivo dMRI (mesoscale at isotropic 500μm), we propose a novel SuperRes-EPTI technique that combines our recently developed EPTI technique with a rotating-view super-resolution acquisition and reconstruction. The SuperRes-EPTI can achieve an overall 3.5× SNR gain (SuperRes×EPTI = 2.7×1.3), while providing images completely-free from distortions that allow for improved super-resolution reconstruction and high effective resolution. The SuperRes acquisition scheme was designed to avoid spin-history artifacts, and incorporates rigid motion correction between thick-slice volumes for high motion-robustness. In-vivo distortion-free dMRI data were acquired at 500μm-isotropic resolution at 3T that reveals detailed fibers in gray matter.