Dear SPMers,
I am having difficult time segmenting MPRAGE acquired on 3T with SPM5,
and am running out ideas of what might be the problem. Segmentation
tends to miss-classify the external cortical gray matter as CSF.
Problem is persistent if no manual coregistration of MPRAGE to T1
template is not first performed, but even after manual coregistration,
segmentation still classifies significant amount of GM as CSF at the
brain surfaces.
Also, the normalized MPRAGE tends to be imperfectly coregistered to the
MNI template, but the fit is only slightly off... My MPRAGE images
appear to be high quality, with clear intensity distinction between
tissue types.
Any advice on how to trouble-shoot this problem would be greatly
appreciated.
Thank you,
-Ajna Borogovac, Columbia University, NY
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