I am working on a project on cortical asymmetry and I have analyzed vertex-wise cortical thickness/surface area asymmetry. However, I noticed that Freesurfer doesn't not seem to facilitate such analysis for gray matter volume, as after running surfreg -xhemi there is no ?h.volume file in subject/xhemi/surf. I searched the literature and found studies on gray matter density asymmetry with VBM and ROI-based volume asymmetry. Is it true that Freesurfer doesn't offer vertex-wise volume asymmetry analysis? And may I know the rationale?