External Email - Use Caution
Dear Freesurfers,
gray matter volume of the entorhinal cortex (EC) can be obtained either in the ?h.aparc.stats or ?h.BA_exvivo.stats/?h.BA_exvivo.thresh.stats files. Considering that all our T1 images were manually edited on a slice-by-slice basis to correct pial surface misplacements and erroneous white matter segmentation, which volume measure of the EC would be more precise?
I assume that gray matter volume contained in ?h.BA_exvivo.thresh.stats were thresholded at a specific probability value (% of case overlapping). Which probability value was used? Is there a reference paper explaining how probabilistic maps of EC were built based on ex vivo MRI contrast?
Thank you in advance.
Best, Jose L. Cantero
Hi Jose
the threshold is set so that the EC label has the average surface area of the labels that went into the average. It is probably more accurate than the aparc as it is based on actual cytoarchitectural landmarks that are visible in ex vivo mri.
cheers Bruce
On Mon, 4 Feb 2019, Laboratorio de Neurociencia Funcional wrote:
External Email - Use Caution
Dear Freesurfers,
gray matter volume of the entorhinal cortex (EC) can be obtained either in the ?h.aparc.stats or ?h.BA_exvivo.stats/?h.BA_exvivo.thresh.stats files. Considering that all our T1 images were manually edited on a slice-by-slice basis to correct pial surface misplacements and erroneous white matter segmentation, which volume measure of the EC would be more precise?
I assume that gray matter volume contained in ?h.BA_exvivo.thresh.stats were thresholded at a specific probability value (% of case overlapping). Which probability value was used? Is there a reference paper explaining how probabilistic maps of EC were built based on ex vivo MRI contrast?
Thank you in advance.
Best, Jose L. Cantero
External Email - Use Caution
Thank you!
El lun., 4 feb. 2019 a las 15:29, Bruce Fischl (fischl@nmr.mgh.harvard.edu) escribió:
Hi Jose
the threshold is set so that the EC label has the average surface area of the labels that went into the average. It is probably more accurate than the aparc as it is based on actual cytoarchitectural landmarks that are visible in ex vivo mri.
cheers Bruce
On Mon, 4 Feb 2019, Laboratorio de Neurociencia Funcional wrote:
External Email - Use CautionDear Freesurfers,
gray matter volume of the entorhinal cortex (EC) can be obtained either
in the ?h.aparc.stats or
?h.BA_exvivo.stats/?h.BA_exvivo.thresh.stats files. Considering that all
our T1 images were manually edited on a
slice-by-slice basis to correct pial surface misplacements and erroneous
white matter segmentation, which volume
measure of the EC would be more precise?
I assume that gray matter volume contained in ?h.BA_exvivo.thresh.stats
were thresholded at a specific probability
value (% of case overlapping). Which probability value was used? Is
there a reference paper explaining how
probabilistic maps of EC were built based on ex vivo MRI contrast?
Thank you in advance.
Best, Jose L. Cantero
Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
freesurfer@nmr.mgh.harvard.edu
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Bruce Fischl -
Laboratorio de Neurociencia Funcional