Hi Athena,
Small pieces of skull left is fine as long as the surfaces look okay. But if they don't or if you want to edit the skull for any other reason, you can do it manually but be careful not to edit the grey matter, which will affect the surfaces. If there is a large chunk of skull remaining or brain missing, you are better off using the automated procedures to save time instead of the manual edits. To remove the skull, try different values for the watershed threshold (20, 15, 10 etc..)
Please refer to this wiki for more info. https://surfer.nmr.mgh.harvard.edu/fswiki/FsTutorial/SkullStripFix
Sita.
On Wed, 6 May 2009, Drosos, Athena wrote:
Hi,
I am part of a group interested in measuring cortical thickness and we have had problems with skull stripping. We read on the mailing list that you are not supposed to delete the skull with the edit voxel tool on the brainmask.mgz because it affects the surfaces. What would be an appropriate way to delete/remove the skull? We tried lowering the watershed threshold (normally at 5) to 3, and found skull still being classified as brain as well as some brain missing.
Thank you, I look forward to hearing your response.
Sincerely,
Athena
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