Hello,

I am new to FreeSurfer and had a quick question about the calculation of cortical volumes using the aparc2aseg. In the aseg images, "cortical volume" is sometimes assigned to extra dura at the superior midline of the brain. My understanding is that this dura will not impact my final gray matter cortical volumes output by aparc2aseg as the cortical ribbon masks are used by default to only calculate volume for voxels that fall with in these masks (lh.ribbon.mgz and rh.ribbon.mgz). Is this correct? (I.e. Should I be manually removing the aseg areas of dura labeled as "cortical" if they fall outside the pial surface/cortical ribbon, or will using aparc2aseg take care of this for me? I want to verify that assuming the latter is indeed correct!)

Thanks for your help!

Megan