I have subject proceed with Freesurfer 4.30 and Freesurfer 5.1. The subjects proceed with Freesurfer 5.1 appears to have thicker cortex than in Freesurfer 4.30. When I correlate the cortical thickness against continuous variables like IQ, I get a difference. Is this expected since I get a correlation on the different side with Freesurfer 4.30 and Freesurfer 5.1.? Can part of the explanation be that Freesurfer 5.1 does not use mri_gcut, and that the registration transformation is changed in Freesurfer 5.1? I get different ras_vox matrix transformation and different flip angle.
Knut J
Hi Knut
have you visually inspected the surfaces? Certainly you will get differences, and our hope would be that 5.1 is more accurate.
cheers Bruce On Mon, 5 Dec 2011, Knut J Bjuland wrote:
I have subject proceed with Freesurfer 4.30 and Freesurfer 5.1. The subjects proceed with Freesurfer 5.1 appears to have thicker cortex than in Freesurfer 4.30. When I correlate the cortical thickness against continuous variables like IQ, I get a difference. Is this expected since I get a correlation on the different side with Freesurfer 4.30 and Freesurfer 5.1.? Can part of the explanation be that Freesurfer 5.1 does not use mri_gcut, and that the registration transformation is changed in Freesurfer 5.1? I get different ras_vox matrix transformation and different flip angle.
Knut J
freesurfer@nmr.mgh.harvard.edu
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Bruce Fischl -
Knut J Bjuland