Recently I used prelude and fugue to perform EPI distortion correction.
I have dual gradient echo image
After I use prelude to unwrap the phase image of echo 2 and echo 1, then I use
fslmaths unwrap_1 -sub unwrap_2 -mul 1000 -div 1 fieldmap
to create the fieldmap.
then I use the following command line to correct distortion
fugue -i epi --dwell=0.004 --loadfmap=fieldmap -u result
my epi scanning parameters
TR 2000ms, TE 20ms, bandwidth=200000Hz, matrix=80*80
then the result I get has no difference between my input raw epi image.
I have tried different options in the fugue command
But the result is still the same with the raw image.
Did anyone face this problem before can share your experience?
Thanks!
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