Hello, I've been asked to obtain freesurfer volume measurements on some cases we've already run with Freesurfer for comparison to VBM measurements. Can anyone direct me to any literature or briefly share knowledge about comparing these two methods?
Second question: For said analysis, I'd like to get the total white and grey matter volume from the Freesurfer cases. The cases were run with Freesurfer 4.2, so I don't have access to some of the tools I'm found referenced in discussions of finding total grey matter in the mailing list archives. How does this look for a total grey matter method? somewhat taken from http://www.mail-archive.com/freesurfer@nmr.mgh.harvard.edu/msg10468.html
1. Get total supratentorial (i.e. sans cerebellum) WM+GM volume. ("BrainSegVolNotVent" in wmparc.stats) 2. Get cerebral WM volume. (wmparc.stats reports the value of total cerebral white matter volume) 3. Subtract 2 from 1 to get total supratentorial GM volume. 4. Get whole brain GM and WM volumes by adding in cerebellar volumes.(wmparc.stats L/R Cerebellum WM/Cortex) 5. Calculate total CSF volumes by summing the individual ventricle and "other" CSF values.(calculate from aseg.stats or wmparc.stats by summing *-Lateral-Ventricle, *-Inf-Lat-Vent, 3rd-Ventricle, 4th-Ventricle, CSF, and 5th-Ventricle)
Thanks very much to anyone with time to respond,
Thomas Ballinger Research Assistant at PNL at BWH