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Hello all,
We are working on calculating the volume of thalamic nuclei in our participants and noticed that there is often a discrepancy in measured volume in the ThalamicNuclei.v12.T1.volumes.txt and the volume calculated for the same thalamic nucleus using fslstats -V. (Note that the nuclei are all created in FreeSurfer, just extracted to individual .nii files afterwards).
For example: in one control subject, the volume of the right VPL was measured in FreeSurfer as 264.650938 mm^3, but the same extracted label in fslstats shows a volume of 242 mm^3. What could be causing this discrepancy?
Thanks
Corinna
Hi Corinna, this is probably due to partial volume correction. The thalamic seg does not just count up voxels. The underlying model is a tetrehdra mesh, and that is used to compute partial volume. doug
On 6/29/2020 6:06 PM, Corinna Bauer wrote:
External Email - Use Caution
Hello all,
We are working on calculating the volume of thalamic nuclei in our participants and noticed that there is often a discrepancy in measured volume in the ThalamicNuclei.v12.T1.volumes.txt and the volume calculated for the same thalamic nucleus using fslstats -V. (Note that the nuclei are all created in FreeSurfer, just extracted to individual .nii files afterwards).
For example: in one control subject, the volume of the right VPL was measured in FreeSurfer as 264.650938 mm^3, but the same extracted label in fslstats shows a volume of 242 mm^3. What could be causing this discrepancy?
Thanks
Corinna
Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
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Hi Doug,
That is helpful, thank you.
Best,
Corinna
On Tue, Jun 30, 2020 at 10:11 AM Douglas N. Greve dgreve@mgh.harvard.edu wrote:
Hi Corinna, this is probably due to partial volume correction. The thalamic seg does not just count up voxels. The underlying model is a tetrehdra mesh, and that is used to compute partial volume. doug
On 6/29/2020 6:06 PM, Corinna Bauer wrote:
External Email - Use CautionHello all,
We are working on calculating the volume of thalamic nuclei in our participants and noticed that there is often a discrepancy in measured volume in the ThalamicNuclei.v12.T1.volumes.txt and the volume calculated for the same thalamic nucleus using fslstats -V. (Note that the nuclei are all created in FreeSurfer, just extracted to individual .nii files afterwards).
For example: in one control subject, the volume of the right VPL was measured in FreeSurfer as 264.650938 mm^3, but the same extracted label in fslstats shows a volume of 242 mm^3. What could be causing this discrepancy?
Thanks
Corinna
Freesurfer mailing listFreesurfer@nmr.mgh.harvard.eduhttps://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
freesurfer@nmr.mgh.harvard.edu
-
Corinna Bauer -
Douglas N. Greve