Photoreceptor identification and quantitative analysis for the detection of retinal disease using AO-OCT imaging

摘要

Adaptive optics (AO) enables imaging of cellular structures in the retina that are not visible with clinical imagingtechniques, providing the potential for earlier detection of retinal disease and enhanced monitoring of progression. Theaim of this work was to develop automated, quantitative techniques for characterizing the morphology of the posteriorretina in AO-OCT B-scans. Images were obtained from a custom-built dual-modality AO-optical coherence tomographyscanninglaser ophthalmoscopy (AO-OCT-SLO) imaging system. Automated segmentation and cone identificationprocedures were developed and applied to images from two groups: healthy controls and dry age-related maculardegeneration (AMD) subjects. Results from the automated routines were compared to measurements made manually byan expert human reviewer, demonstrating good agreement. Results from the control subjects showed decreasing cone innerand outer segment lengths with increasing distance from the fovea. The cone outer segment tip (COST) layer had a greatervariation in axial position compared to the inner segment/outer segment (IS/OS) junction. Results from the AMD groupindicate that disruption in the COST layer over drusen occurs earlier and to a greater extent than the IS/OS junction, whichmay be useful in the detection of emerging drusen.