Ileana Hancu1, Ek Tsoon Tan1, Luca Marinelli1, Nathan White2, Dominic Holland2, Tim Sprenger3, and Jonathan Sperl3
1GE Global Research Center, Niskayuna, NY, United States, 2University of California San Diego, San Diego, CA, United States, 3GE Global Research Center, Munich, Germany
The performance of four distortion correction
algorithms was investigated in a cohort of normal volunteers. While all
approaches reduced distortion, it was found that the reversed polarity gradient
methods were inherently better than registration or B0-mapping approaches.
It was likely that the limited degrees of freedom of the registration approach could
not account for localized magnetic field inhomogeneity. The extrapolation of B0
maps in the distorted EPI space introduced errors that decreased the overall
performance of the B0-mapping method.