Combined adaptive optics (AO) optical coherence tomography (OCT) scanning laser ophthalmoscopy (SLO) imaging
allows simultaneous en face and cross sectional views of the retina. We describe improvements to our AO-OCT-SLO
system and highlight its resolution capability and clinical utility by presenting results from 3 control and 4 dry agerelated
macular degeneration (AMD) subjects. From a group of subjects with healthy eyes, OCT A-scans were grouped
as originating from cones or rods and were averaged. The resulting reflectance profiles were then used to identify the
location of cone and rod segments. Results for rods and cones were compared, with the focus on inner segment (IS) and
outer segment (OS) structures and where these cells embed into the retinal pigment epithelium (RPE). In the AMD
patients, cone IS and OS lengths were measured over and around drusen for two retinal regions (fovea–2° and 2°–4°),
and those results were correlated to drusen height. For the fovea–2° region, the drusen height that caused statistically
significant shortening of cone ISL and OSL compared to the unaffected adjacent area were 40 μm and 50 μm
respectively (p = 0.009, and p < 0.001, respectively). For the 2°–4° region, the equivalent drusen heights that caused
significant shortening of segment length were 60 μm for IS (p = 0.017) and 80 μm for OS (p < 0.001)
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