On 29 June 2015 at 09:33, Mohamed Ali Bahri <[log in to unmask]> wrote:
> Dear expert,
> I used DARTEL to normalize and extract the warped modulated GM, WM, and CSF
> for a VBM study. Which image should be used to compute the total inracarnial
> volume (ITV)? Should I use the output of unified segmention C1,C2,C3 or the
> dartel imported images (rC1,rC2,rC3)?
Assuming SPM12 I'd suggest using Segment followed by the Tissue
Volumes tool available in the batch editor (SPM|Utils|Tissue Volumes I
think). By default that includes an ICV mask which improves the
accuracy of the estimate, based on C1, C2, C3. (Plug:
It's possible better normalisation with DARTEL would produce a better
result, but I don't think the tissue volume tool will work with DARTEL
outputs and I think DARTEL is normally used with a study-specific
template, rather than normalisation to MNI, so would not necessarily
correspond to the ICV mask which is defined for the MNI template.