Correlation between SD‐OCT, immunocytochemistry and functional findings in an animal model of retinal degeneration

Purpose The P23H rhodopsin mutation is an extensively studied model of ADRP. We evaluated the anatomical changes using SD‐OCT and correlate the findings and retinal thickness values with immunocytochemistry. Functional changes were analyzed Methods Heterozygous P23H pigmented transgenic rats aged from P18 to P180 were studied. LE rats bred with Sprague Dawley (SD) 1 month old served as wild type controls. Visual acuity and contrast sensitivity evaluation was performed every month. Corneal ERGs were recorded under scotopic and photopic conditions. Retinal thicknesses at different levels (total thickness, ONL + RPE, ONL and IPL), fundus autofluorescence (FAF) and fluorescein angiography was performed in 3 animals at P150 using Spectralis OCT and HRA (Heidelberg Engineering, Germany). Retinas were immunostained for ICC. Results Retinal thicknesses diminution was seen in OCT sections, with a clear loss of ONL and morphological modifications. Statically differences were found between groups in all evaluated thicknesses. In the P23H rats, change in FAF was noted comparing to control group, as sparse autofluorescent dots. No relevant changes were observed in the angiography pattern. ICC showed a progressive decrease in ONL thickness. Functional changes were progressive with time. Conclusion Anatomical changes in pigmented P23H can be observed using SD‐OCT and immunocytochemistry, with a good correlation between their values. SD‐OCT and FAF are important tools for research in retinal degenerations.