Matt,
weeell, It's clear I've got some sort of issue with getting my directions
right. I've got the right vectors, but I wasn't sure about the signs. So I
tried about every permutation of negating x,y, and/or z in my bvecs file and
running it through DTIFit. Looking at the primary eigenvectors resulting
from each permutation made it pretty obvious which was the right one....
there was only one result that gave V1 line segments (in FSL_View) that
matched the corpus callosum anatomy in all directions. However, when I ran
those exact same data and bvecs through BEDPOST, it was as if it was using a
bvecs file where x had been negated (x*-1). Even if I do have an error in my
bvecs file, shouldn't I get the same erroneous result from both programs?
I'll rerun BEDPOST tonite to be sure it replicates, but I already double
checked all my command lines.
Thanks,
Ruth
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