Hi.
I would like to correct geometric distortions in images from open-magnet using
FSL. I reconstructed modulus and phase images from the raw (k-space) data.
The modulus image looks fine, but the phase image looks strange. It has a
"checker board" pattern on top of known phase wraps.
http://www.uku.fi/~kavec/phase.hdr
http://www.uku.fi/~kavec/phase.img
I want to use these images to generate a field map after acquiring the second
TE data.
I am not sure what's going wrong way. Could it be SNR ~ 10-15? Something wrong
in my reconstruction? The data were acquired with 3D-GRE with 30% off-center
echo sampling.
Any help is appreciated.
Martin
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