[Freesurfer] Defect Holes different between scans in same subject

We have a study where subjects are scanned one, and a second time 6 months later. I am looking for changes between the two time point and often times there is a large difference in the "number of defect holes prior to fixing" within the same subject.

Can anyone comment on the significance of this? Given the same brain being scanned 6 months later, how / why is there such a difference?

[Logo] Brad J. Matushewski, M.Sc., R.Kin., CSEP-CEP. Laboratory for Brain & Heart Health School of Kinesiology Western University Room 402, Arthur & Sonia Labatt Health Sciences Building London, ON, Canada, N6A 5B9 Tel: (519) 661-2111 x 89066 Fax: (519) 850-2447