Optical Coherence Tomography Identification of Occult Choroidal Neovascularization in Age-related Macular Degeneration

Abstract

To evaluate and describe the various optical coherence tomography (OCT) features of occult choroidal neovascularization (CNV) in age-related macular degeneration (AMD) at the time of diagnosis. Prospective, consecutive, observational case series. One hundred and fifty-three eyes of 130 consecutive patients with subfoveal occult CNV diagnosed on scanning laser ophthalmoscope (SLO) fluorescein angiography (FA) and SLO indocyanine green angiography (ICGA) were evaluated with OCT. The diagnostic criteria for occult CNV on angiography were heterogeneous hyperfluorescence with late leakage in the macular region associated with pigment epithelial detachment (PED), stippled hyperfluorescent dots, and signs of deterioration. OCT findings were evaluated and described. A PED was observed on OCT in 98% (150 eyes) either as a limited retinal pigment epithelium (RPE) elevation (54 eyes [35.3%]) or a complete detachment (96 eyes [62.7%]). Occult CNV corresponded to zones of hyperreflectivity in contact with the RPE band and was detected in 62.7% of eyes. In fibrovascular PED (63 eyes [65.5%]), the elevated RPE was highlighted posteriorly by a moderately reflective band overlying a hyporeflective cavity. In serous PED, the cavity remained optically empty. The RPE in the detached zone showed changes such as fragmentation (137 eyes [89.5%]). OCT also showed intraretinal (122 eyes [79.7%]) and subretinal (64 eyes [41.8%]) fluid. Analysis of the various OCT features observed in this study confirms the polymorphic nature of occult CNV in AMD, their exudative reactions, the almost constant presence of PED, and the different changes in the RPE band. OCT examination, therefore, provides valuable data to confirm the features of subepithelial occult CNV.