I assume you mean on an  ROI basis. They are usually correlated in some way because volume = thickness*area. The only way they could not be correlated is if the area were to change opposite to thickness -- but almost always they are both moving in the same direction, down:(

On 1/25/2023 10:25 AM, John Anderson wrote:

External Email - Use Caution

Dear experts, this is the first time I have used Freesurfer. I am a clinician and I don't have previous experience. I followed wiki instructions. I have a group of T1 images. I need cortical thickness and cortical gray matter volume measurements . I ran "recon-all" and I got all the measurements. My question is about cortical thickness and cortical gray matter volume, are these two measurements have to be correlated everytime? Is it possible to find cases of cortical thinning and normal cortical gray matter volume? I don't have a solid mathematical background. I am wondering if  those two numbers must always correlate with each other, otherwise  I am worried that an error in the analysis may lead to cortical thinning and normal cortical gray matter volume.

Thank you for your time, John

---

Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer