Dear All,
I am trying to use TBSS to derive asymmetry indices. To do this I have,
1) Made the FA template symmetrical by creating a flipped version
(fslswapdim applied) and averaging the flipped and unflipped versions
2) Registered all data to new template using tbss scripts 1, 2 and 3
3) Taken the mean FA skeleton and made this symmetrical using the same
method as above
4) Fed my all_FA data into tbss 4 together with the new symmetrical skeleton
- here I was expecting voxels from each subject to be projected onto the
symmetrical skeleton which I could then flip again and use (unflipped minus
flipped) to derive AI.
However, the all_FA_skeletonised output I get is not quite symmetrical. The
deprojection step seems to have ignored the use of the new symmetrical
skeleton, and instead used the old, unsymmetrical one.
Any help, tips as to a better method would be welcome.
Thanks.
Pete
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