Hello! I've never done B0 corrections before but this forum has been very helpful to me. Currently, I'm trying to apply B0 corrections to some EPI data that I have, and my end result has been coming out looking a little funny. I've been successful in converting the phases into the right range [0-2pi] and the fieldmap generated has looked reasonable (to me at least). However, when I apply the correction, I get a moderate case of demonbrain (a clump of voxels stretching out of the brain and past skull in a spike). Looking at the shift map, it does seem as though there's an odd value corresponding to where the brain becomes deformed. I attempted to use FUGUE's despiking command to potentially fix this, but when I used the output from despiking as the fieldmap there seemed to be more deformation (in addition, the thresholded signal loss weighting images did not seem to show the whole brain anymore: all show a single orientation and the left quarter or so is missing). Any insight into these problems would be helpful!
Best,
Steven
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