In the image comparing the subfield segmentation for versions 5.3 and 6.0 found at https://surfer.nmr.mgh.harvard.edu/fswiki/HippocampalSubfields, the segmentation by version 6.0 does not capture a gray segment that 5.3 includes, located superior to the other regions.  Was it omitted by 6.0 because it is part of a separate anatomical structure, not hippocampus?  As a second question, in each case, does the totality of the colored subregions comprise what would be considered to be the total hippocampal volume (at least as represented in the slice shown)?

Thanks very much for your time in answering.