Robust 2D Phase Correction for Echo-Planar Imaging Under a Tight Field-Of-View

Dan Xu¹, Kevin F. King¹, Yuval Zur², R. Scott Hinks¹

The existing 2D phase correction methods to reduce Nyquist ghost in echo-planar imaging (EPI) have several unaddressed issues that largely affect their practicality. These issues include uncharacterized noise behavior, image artifact due to unoptimized phase estimation, and most seriously a new image artifact under tight FOV. We propose a modified, more robust method that addresses all the abovementioned issues. Various EPI results show that the proposed method can robustly generate images free of Nyquist ghost and some other image artifacts even in oblique scans or when cross-term eddy current terms are significant.