Edge-guided Localized Phase Unwrapping: Application to SWI
Thayyullathil H, Schuff N, Weiner M, Stables L
DVA Medical Center and University of California San Francisco
Accurate measurement of phase is essential in many contexts in MRI, such as in susceptibility-weighted imaging (SWI), flow imaging, and Bo field-maps. In such situations, artificial discontinuities in phase images called 'phase wraps' are not desirable.We have formulated and implemented a computationally efficient phase unwrapping method, which is able to preserve subtle features in the phase images while unwrapping severe phase wraps. Phase values are altered only at regions of wraps, guided by the linked edges present in the wrapped phase image. We have applied the method on both synthetic objects and experimental SWI phase images.