The ICV is not computed based on a sum of the volumes of individual structures. It is a summary measure computed from the registration to talairach space. See the wiki and Randy Buckner's paper for more info. As for combining across field strengths, that would not be highly recommended. If you want to do this, make sure to include a regressor for field strength in your GLM. Try looking at the Han paper.
doug
Tadeu Kubo wrote:
Hi FS,
I have two important doubts...
Is it the CSF volume included in the ICV volume (aseg.stats)?
Is it possible include in the same group patient acquired from 1.5T and 3.0T? Do you have an article about this topic?
TK
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