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I’m comparing output of Freesurfer5.2 to 6 on the same set of brains. The “5th ventricle” (Cavum septum pellucidum) is not being detected by 6. I had eyeballed the output from 5.2 and convinced myself it was reasonably well detecting this developmentally abnormal finding pretty well. I am wondering what changed in version 6, if anything, that could explain this?