Optical Coherence Tomography and Fundus Autofluorescence evaluation in an animal model of Retinal Degeneration

Abstract

PurposeTo evaluate fundus autofluorescence (FAF) and OCT changes comparing with immunohistochemical (ICC) analysis in long term degeneration of P23H rat and to investigate retinal and choroidal vascularization using fluorescein and indocianin green angiography.MethodsTwenty‐albino homozygous P23H line 1 rats aging from 18 postnatal days (P18) to 27 months and wild‐type albino Sprague‐Dawley (SD rats) (2 and 15 months old) were used for this study. Normal pigmented Long Evans (LE) 2 months old rats were used to compare FAF findings. ICC was performed to correlate with the findings of OCT and AF changes.ResultsFAF pattern varied from not findings at P18 to a mosaic of hyperfluorescent dots in the rats of 6 months or older. Retinal thicknesses diminished during the time: 205.2–183.18 μm in SD rats and 189.88–58.15 μm in P23H rats. In long term degeneration, OCT showed severe changes at the retinal layers; ICC helped to identify the cell loss and remodeling changes.ConclusionsAutofluorescent ophthalmoscopy is a non‐invasive method that can detect changes in metabolic activity at the RPE in animal models of retinal degeneration in vivo. Retinal vascular plexus changed with aging. OCT showed a diminution of retinal thickness and retinal layer changes with the degeneration. ICC shows a good correlation.