Hello all,
We've recently run into a problem using SPM to normalize functional scans
acquired on our 3T magnet. Because it's a 3T, we get 'blow-out' of
orbital, frontal cortex due to the nasal sinuses. This means that the
brains we acquire have a peculiar shape (no orbital cortex). When we go to
normalize these, SPM warps them into standard space -- but SPM doesn't know
that they have no orbital cortex. This results in distortions: much of
the brain is dragged anterior and inferior to where it really should be.
The stuctural scans are not affected in the same way, and they normalize
correctly. However, applying the parameters determined by normalizing the
structurals to the functionals results in much the same problem.
Does anyone have any fixes for this sort of problem?
Many thanks,
Glenn Wylie.
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