Hi, Using fslmaths with the -roi option would be the easiest way, assuming that the image is already in standard space. All the best, Mark On 29 Jul 2011, at 03:34, Paula Wu wrote: > Dear all, > > I'd like to divide in half an ROI that I made from Freesurfer by making a coronal cut at the Talairach coordinate Y=(some value) . Is there a way to do this in FSL? > > Thanks! > Paula