yes, we do a partial volume correction of the volumes, accounting for the fraction of the structure in each border voxel.
cheers Bruce On Mon, 15 Feb 2010, Hui J Yu wrote: > Dear Freesurfer users, > > I am wondering how are the volumes calculated from stats such aseg.stat. > When I export the aseg and do a voxel count and multiple the volume per > voxel, my total volume is different from that is given by the stats. For > example, the hippocampal volume given by aseg.stats for one of my controls is > 4000 cm3, but when I export the aseg.mgz into matlab and do a voxel count (my > original voxel volume is 1mm3 isotropic) for that labeled mask, the total > volume is aorund 3000 cm3. Does freesurfer does some sort of intensity > normalization or partial volume correction? Even if so, the magnitude of > difference is large that I am puzzled. > > Thank you very much. > > > _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
