Morphological features of abnormal fundus autofluorescence (FAF) using Spectral Domain OCT

Abstract

Abstract Purpose To evaluate morphological features of hyper and hypo autofluorescence areas using Spectral Domain OCT technology. Methods 16 patients ( 10 male , 6 females ) with first diagnosis of age related maculopathy and dry AMD have been enrolled.Visual acuity test ( Snellen chart ) and Amsler’ grid test have been performed. Patients underwent to fundus autofluorescence ( FAF ) study (cSLO HRA 2 Laser source 488 nm , Barrier filter 500 nm, Heidelberg , Germany ) and Specral Domain OCT evaluation ( SD OCT OTI , Canada ). The FAF abnormalities have been compared to OCT images using gray scale and colour inversion system. Abnormalities in outer limiting membrane ( OLM ) profile , photoreceptor inner‐outer segment junction and RPE layer have been recorded for each patient. Results OCT did not show any morphological changes in areas of hyperautofluorescence . In cases of hypoautofluorescence , main OCT changes were : abnormal profile of the OLM with continuous gaps , disruption of the IS/OS junction with focal breaks and granular destructuration of the RPE layer .No alterations inside neurosensory retina or modifications of retinal thickness and volume have been recorded. Conclusion Abnormal FAF is mainly derived from RPE lipofuscin . Excessive accumulation of lipofuscin has been associated with degeneration of RPE cells and photoreceptors. SD‐OCT is able to show retinal morphological changes associated to abnormal FAF improving our knowledge in pathophisiologic pathways.