Retinal pigment epithelial features indicative of neovascular progression in age-related macular degeneration

Abstract

Purpose : To identify characteristic retinal pigment epithelium (RPE) changes in fellow eyes of patients with neovascular age-related macular degeneration (nAMD) using polarization-sensitive optical coherence tomography (PS-OCT).

Methods : Thirty-one fellow eyes of 31 patients with unilateral nAMD were evaluated in this cohort study of a prospective interventional trial. PS-OCT as well as conventional imaging systems including spectral-domain (SD-) OCT and fluorescein angiography (FA) were performed using a standardized protocol. Monitoring visits were performed continuously at one-month intervals. Morphological RPE features associated with the development of choroidal neovascularization (CNV) were systematically analyzed.

Results : Mean follow-up was 29 months (±17, SD). Thirteen (42%) of 31 eyes developed de novo CNV: 9 eyes type I CNV, 2 eyes type II CNV, 2 eyes a RAP lesion. RPE thickening and reticular pseudodrusen (RPD) were observed significantly more often in eyes, which progressed towards CNV than in eyes, which did not progress (p=0.008 and p=0.001). Monthly increase in drusen volume was higher in the CNV group with a median increase of +2.2% in area and +2.9% in volume compared with +0.8% and +0.6% in the non-progressing group. RPE migration within the neurosensory retina and at the level of the RPE layer resulting in RPE thickening was seen topographically and chronologically associated with CNV development.

Conclusions : Conversion to CNV is associated with qualitative (RPD, RPE migration, RPE thickening) and quantitative RPE characteristics (drusen volume). Early detection of these features may allow more efficient screening in risk eyes and timely vision-preserving treatment in eyes developing neovascular disease.

This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.