Hi John
why do you want to correct for them? They likely represent a pathological process, so correcting for them may remove whatever effects you are looking for, no? The space between the sulci and the ventricle volume won't directly affect surface-based analysis, but of course the sulcal widening likely reflects cortical atrophy that will be
cheers Bruce
On Wed, 11 Jul 2018, John Anderson wrote:
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Dear Freesurfer experts, I have two groups of subjects (healthy and patients). The patients have different degrees of atrophy. Looking into the individual scans, the subjects are largely different in the space between the sulcuses and the size of ventricles. My questions are:
- Is there any way to correct for these differences in the surface based analysis?
- Including eTIV covariate does it help in this case?
- Does the resampling to "fsaverage" overcome the challenge of these differences between the
subjects?
I appreciate any advice, John