Hi everyone,
After running -hippo-subfields, I converted the voxel output of -hippo-subfields to mm^3 based on the instructions given here: https://mail.nmr.mgh.harvard.edu/pipermail/freesurfer/2013-June/031188.html. Then I summed the volumes for all of the subfields (assuming that this would give me the total hippocampal volume), and compared the sum to the hippocampal volume that FreeSurfer gave after running recon-all -all on the same scan. They weren't the same! Why would these differ? Or, is there something I am doing wrong in my comparison of the two hippocampal outputs?
Thanks for your help!
Hi Sierra, the hippocampal subfield segmentation is computed using a separate model, so it doesn't agree perfectly with the hippocampal mask in aseg.mgz. In fact, the volume estimates tend to be a bit smaller (but highly correlated). Cheers, /Eugenio
On 09/30/2013 10:42 AM, Germeyan, Sierra (NIH/NINDS) [F] wrote:
Hi everyone,
After running -hippo-subfields, I converted the voxel output of -hippo-subfields to mm^3 based on the instructions given here: https://mail.nmr.mgh.harvard.edu/pipermail/freesurfer/2013-June/031188.html. Then I summed the volumes for all of the subfields (assuming that this would give me the total hippocampal volume), and compared the sum to the hippocampal volume that FreeSurfer gave after running recon-all -all on the same scan. They weren't the same! Why would these differ? Or, is there something I am doing wrong in my comparison of the two hippocampal outputs?
Thanks for your help!
Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
freesurfer@nmr.mgh.harvard.edu
-
Germeyan, Sierra (NIH/NINDS) [F] -
Juan Eugenio Iglesias