On 20 Aug 2011, at 08:55, Sourena Soheilinezhad wrote:
Hi,
Is it possible to export TBSS calculated warps with the current FSL version?
I would like to combine TBSS transformation vectors and white-gray matter boundary normalization warps among subjects to produce a transformation field covering the entire white-matter diffusion data (interpolating transformation in regions not belonging to the skeleton or boundary).
The initial FNIRT warp covers the whole image and not just the skeleton - so you could use this (see warp files in the FA directory and the TBSS scripts for more info) - however the final skeleton projection step applies only to the skeleton, not all of the image.
Also please give me a comment if carrying out direct analysis on the diffusion vectors (e.g. Watson-Williams spherical statistic test on V1) could yield further benefit than FA, since this test calculates significant directional difference among vector groups.
Possibly - though this needs a lot of thought wrt what the most sensible transformation (particularly rotation obviously) should be applied before comparing this across subjects. One might argue that if the registration is done well and rotations applied appropriately, there should be nothing left to vary across subjects!
Cheers.
Thanks in advance,
Sourena