Short-term natural history of macular neovascularization in nonexudative age-related macular degeneration using multimodal imaging

The short-term conversion rate of a non-exudative macular neovascularization (ne-MNV) to an exudative stage in age-related macular degeneration (AMD) was evaluated in a single-center, retrospective case control study and associated imaging characteristics described, using multimodal imaging. A total of 241 Caucasian patients with unilateral, treatment-naive exudative neovascular AMD were screened for the presence of a ne-MNV in the fellow eye between March 2016 and May 2022. Eyes with a confirmed ne-MNV on indocyanine green angiography and/or optical coherence tomography angiography (OCTA) were monitored using structural OCT for signs of exudation. The main outcome was to evaluate multimodal imaging biomarkers to identify predictors of exudative conversion.Among 241 study eyes, 40 (16.6%) showed ne-MNV at baseline, all classified as type 1 MNV. During follow-up, 13 patients (32.5%) progressed to an exudative stage, with a mean time to exudation of 12.6 months (range: 2.6-22.4 months). The presence of a shallow irregular retinal pigment epithelial elevation (SIRE) was the only statistically significant feature associated with an increased risk of conversion to exudation. (p = 0.012) Patients with ne-MNV and a baseline SIRE are at increased risk for exudation. SIRE can be easily identified and followed up with structural OCT, providing a valuable marker for monitoring ne-MNV activation.