Hi all!
I would like to use fugue to correct distortions on my dti data using a
field map.
I did the following:
1) eddy_correct dti data
2) extract and bet b0 image
3) bet magnitude, mask fieldmap with betted magnitude
4) warp magnitude (fugue -w)
5) flirt -dof 6 warped magnitude to betted b0
6) apply flirt transform to masked fieldmap
7) unwarp dti data (fugue -u)
8) dtifit
9) flirt -dof 6 FA to structural (T1)
I found that the corpus callosum in the FA map (and corrected b0 image)
is "stretched" when compared to the structural image (see attachment).
The screenshot shows the structural image, overlaid in red with FA
(thresholded at 0.3).
Does anyone know what might cause this problem, and how I could fix it?
Thanks for your help!
Cheers
Kerstin
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