I am rather new (a few days in fact) to Freesurfer, so forgive me if I have some lack of knowledge.

I am currently working with T1 MRI and CT scans of patients that are undergoing epilepsy surgery, and am interested in using the transformation that freesurfer uses to "inflate" the cortical surface into a sphere for "inflating" the electrode contacts onto the spherical surface as well. 

However, I am not sure if Freesurfer saves this transformation matrix done on the cortical surface? If so, is there a way I can extract that? 

Thank you!
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