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Abstract #3771

Phase-Labeled Reference EPI for Frequency-Segmented Inhomogeneity Corrections (PREFICS)

Mario Zeller1, Alexander Mller1, Dietbert Hahn1, Herbert Kstler1

1Institute of Radiology, University of Wrzburg, Wrzburg, Germany

Artifacts induced by field inhomogeneities in non-Cartesian EPI acquisitions typically cannot be corrected by simple pixel-shifting. Instead, conjugate phase based methods can be applied. These methods require the acquisition of a separate gradient-echo field map. The acquisition of such a map is relatively time-consuming, as multiple radiofrequency pulses are applied. In this work, a method is described, which allows deriving the field map from a phase-labeled reference EPI scan comprising of only two fast EPI acquisitions. With this map, geometric distortions arising in non-Cartesian EPI can be successfully corrected.

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Keywords

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