Spatial analysis of thickness changes in ten retinal layers of Alzheimer’s disease patients based on optical coherence tomography

Thickness changes in the 10 retinal layers were studied in patients with AD at a very early stage of disease development. We automatically segmented 10 retinal layers, evaluated their thickness at each retinal point scanned, and searched for spatial patterns of thickness differences between patients and controls. All 10 layers showed AD-related thinning over a relevant percent of their surface, and thinning reached statistical significance at various locations in NFL, GCL, IPL, INL, OSL and total retina. All layers except INL and OS also showed thickened regions, though their thickening did not reach statistical significance. In neural layers thinned regions showed a statistically significant increase in area over that of thickened ones, whereas the opposite was observed in the RPE. Volume lost in thinned regions of neural layers was greater than volume gained in thickened regions,…