Hello, Freesurfer experts:
We are extracting the average cortical thickness of each hemisphere for every subject using mris_anatomical_stats. We found that for one subject (attached below), the thickness measures are quite similar but the “intrinsic curvature index” differs drastically between left/right hemispheres. Will this curvature index affect the validity of our thickness measure?
***the left hemisphere mris_anatomical_stats -l lh.cortex.label -f subject1l.txt subject1 lh limiting computations to label lh.cortex.label. reading volume /usr/local/freesurfer/subjects/subject1/mri/wm.mgz... reading input surface /usr/local/freesurfer/subjects/subject1/surf/lh.white... reading input pial surface /usr/local/freesurfer/subjects/subject1/surf/lh.pial... reading input white surface /usr/local/freesurfer/subjects/subject1/surf/lh.white... structure is "lh.cortex.label" number of vertices = 157421 total surface area = 102165 mm^2 total gray matter volume = 290073 mm^3 average cortical thickness = 2.488 mm +- 0.694 mm average integrated rectified mean curvature = 0.170 average integrated rectified Gaussian curvature = 0.105 folding index = 4980 intrinsic curvature index = 592.3
***the right hemisphere mris_anatomical_stats -l rh.cortex.label -f subject1r.txt subject1 rh limiting computations to label rh.cortex.label. reading volume /usr/local/freesurfer/subjects/subject1/mri/wm.mgz... reading input surface /usr/local/freesurfer/subjects/subject1/surf/rh.white... reading input pial surface /usr/local/freesurfer/subjects/subject1/surf/rh.pial... reading input white surface /usr/local/freesurfer/subjects/subject1/surf/rh.white... structure is "rh.cortex.label" number of vertices = 158401 total surface area = 102285 mm^2 total gray matter volume = 291519 mm^3 average cortical thickness = 2.482 mm +- 0.707 mm average integrated rectified mean curvature = 0.173 average integrated rectified Gaussian curvature = 0.299 folding index = 5756
Thanks in advance
Karl