CORRECTION OF MOTIONAL ARTIFACTS IN DIFFUSION-WEIGHTED IMAGES USING AREFERENCE PHASE MAP

A method of correcting motional artifacts in diffusion-weighted images is described, Motion causes changes in the phase of the k-space NMR s ignal and thereby introduces positional shifts (or ghosts) in the spat ial domain, By correcting the phase of the NMR signal before Fourier t ransformation, the image sharpness is greatly enhanced, The new method measures the phases of the NMR signal once and stores this phase info rmation in a phase map, Subsequent images with motional artifacts are corrected during postprocessing using this reference phase map.