Data from: ASHS-OAP atlas for automatic entorhinal cortex segmentation

Early stages of Alzheimer’s disease (AD) are associated with volume
reductions in specific subregions of the medial temporal lobe (MTL). Using
a manual segmentation method—the Olsen-Amaral-Palombo (OAP) protocol—
previous work in healthy older adults showed that reductions in grey
matter volumes in MTL subregions were associated with lower scores on the
Montreal Cognitive Assessment (MoCA), suggesting atrophy may occur prior
to diagnosis of mild cognitive impairment, a condition that often
progresses to AD. However, current manual segmentation methods are labour
intensive and time consuming. Here, we examined the utility of Automatic
Segmentation of Hippocampal Subfields (ASHS) to detect volumetric
differences in MTL subregions of healthy older adults who varied in
cognitive status as determined by the MoCA. We trained ASHS on the OAP
protocol to create the ASHS-OAP atlas, and then examined how well
automated segmentation replicated the ground truth of manual segmentation.
Volumetric measures obtained from the ASHS-OAP atlas were also contrasted
against those from the ASHS-PMC atlas, a widely used atlas provided by the
ASHS team. Volumetrics from the ASHS-OAP atlas aligned well with those
from manual segmentation, suggesting ASHS-OAP is a viable alternative to
current manual segmentation methods. In addition, while some subtle
differences were observed, results from the ASHS-PMC and ASHS-OAP atlases
aligned well with each other overall. Our findings highlight the utility
of automated segmentation methods but still underscore the need for a
unified and harmonized MTL segmentation atlas.