Dear experts,

I am sending the example subject named chiasma_question.tar.gz to your FTP server.

The issue with encircling chiasma is located in slices ~134-140.

According to Aparc.a2009s+aseg the tissue is marked as optical chiasm, but also part of it is labeled as left cerebral white matter. I guess that for the whole-brain group analysis of cortical thickness this error probably will not have an effect since it seems that this region is masked by cortex.label, but in volumetric analyses there could be an effect, although probably very small. Or could this error cause some bias in cortical parcellation in adjacent cortical areas?...What do you think?

Regards,

Antonin Skoch