Spectral-Domain Optical Coherence Tomography Associations of Neovascular Conversion in Age-Related Macular Degeneration

Abstract

Purpose: To identify spectral-domain optical coherence tomography (SD-OCT) features associated with exudative conversion in fellow eyes of patients treated for neovascular age-related macular degeneration (nAMD) in their first eye. Methods: Retrospective observational study. Spectral-domain optical coherence tomography images of converting fellow eyes (study eyes) from 83 patients with nAMD were compared to fellow eyes of age- and sex-matched patients with nAMD who did not convert (control eyes). Parameters related to drusen, pigment epithelium detachment, hyperreflective foci (HRF), retinal pigment epithelium atrophy, small cystic cavities, and vitreoretinal interface were graded. Longitudinal analysis in study eyes and cross-sectional comparison with control eyes at the last 3 semiannual visits before nAMD conversion were performed. Results: For most biomarkers, the prevalence in study eyes increased and imaging findings worsened more than in control eyes. Drusen size and reticular pseudodrusen presence were significantly greater in converting eyes at all 3 time points. Outer retinal small cystic cavities were significantly more common in study eyes shortly before conversion. Binary logistic regression revealed that biggest drusen width was significantly associated with nAMD at all 3 time points (odds ratio [OR] > 1.010; P < .001). The presence of soft drusen was strongly associated with nAMD 18 months before conversion (OR: 7.034; P = .040). Clustering HRF in the inner retina were significantly associated with nAMD both 12 (OR: 1.324; P = .049) and 6 months (OR: 2.161; P = .035) before conversion. Conclusions: Emergence of HRF in fellow eyes, particularly in the inner retina, are sensitive SD-OCT features indicating conversion to exudative disease in patients treated unilaterally for nAMD.