Hi,
We have spgr images taken 5 minutes after gadolinium infusion. They are high
res, 1x1x1, from 3T magnet. We have 24 subjects, each with a pair of these
images, the pair being before and after an intervention. We have no a priori
hypotheses about where there might be gadolinium leakage, and to compare all
24 subjects pre to post is the approach we would like to take. We have
experience with Randomise for SIENA voxelwise and in TBSS analyses. But even
though the images are very high resolution, and map nicely to MNI space, we
don't have anything like the TBSS skeleton nor the SIENA edge mask to
constrain the individual data for input into Randomise.
We have FLIRTED the pairs to each other, and both to MNI. Is there any other
step you would recommend to prepare the images to get the best Randomise
analysis? Like -dil in SIENA voxelwise?
Maybe we're missing something, but it seems that if each image in the 4-D
input image isn't well-aligned to the same space, that true differences in a
specific region will be obscured by comparing the "wrong" voxels across
images. Is that correct?
Thanks in advance,
Rob
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