I want to segment registered PET to T1 MRI to 45 subcortical regions as the regions in aseg.stats of MRI.
I used  mri_segstats --seg MRI-floder/mri/aparc+aseg.mgz --reg Pet2T1.register.dof12.lta  --sum petsuv.segstats.dat --i PET-SPM.mgh  --ctab-default

into petsuv.segstats.dat, I found only 40 regions, not as aseg.stats
what should I change in my commend?