Horst Schdl1, Siegfried Trattnig1, Simon Robinson1
1Department of Radiology, Medical University Vienna, Vienna, Austria
Phase images can be unwrapped with spatial or temporal approaches. A new and fast temporal approach, suited to highly wrapped phase images at ultra-high field, is UMPIRE. It is based on a multi-echo acquisition with unequal echo spaces, and uses the difference between phase difference images (essentially a wrap-free estimation of B0) to unwrap phase images. UMPIRE was implemented in C using parallelization. The performance of UMPIRE was compared with region growing methods PHUN and PRELUDE using simulated data with complicated shapes and in-vivo images. UMPIRE was dramatically faster than the spatial methods PHUN and PRELUDE in all tests.