[Freesurfer] g-w.pct vs. g-w. ratio

Dear FreeSurfer Support team and Community

I am wondering if someone can give me an explanation of the difference between g-w.pct and g:w ratio (as calculated by; fscalc lh.gm.mgh div lh.wm.mgh -o lh.ratio.mgh)

Will both these measures essentially measure the relationship between grey and white matter signal intensity but in a different way?

Best, Derek

________________________________

Derek Sayre Andrews, MSc PhD Candidate

The Sackler Institute for Translational Neurodevelopment

Department of Forensic and Neurodevelopmental Sciences

Institute of Psychiatry, Psychology & Neuroscience, King's College London

Telephone: +44 (0)20 7848 5701 Email: Derek.Andrews@kcl.ac.uk