Hi,
I was just rereading the thread on averaging multiple DTI acquisitions. As
I understand it, the suggestion was to rotate the 2nd acquisition to line up
with the first acquisition, then continue with tensor calculation. Am I
correct that this would only be valid with small rotations? For example, if
one of the acquisitions had to be rotated 30 degrees in order to line up
with the other (because the subject had moved their head within the
scanner), the directions recorded in it's original bvecs file would no
longer be accurate. That being the case, the 2 acquisitions, with different
bvecs, couldn't be directly averaged. Is this correct?
--Ruth
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