Retention of good visual acuity in eyes with neovascular age-related macular degeneration and chronic refractory subfoveal subretinal fluid

Purpose: To describe the clinical characteristics of a subset of eyes with neovascular age-related macular degeneration (NVAMD) receiving intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy which retain good visual acuity despite chronic, persistent subfoveal subretinal fluid (SRF). Design: Retrospective, observational case series. Methods: Study eyes were identified from a consecutive series of 186 patients treated with anti-VEGF therapy seen for regular follow-up over a 3-month period. The clinical histories of 10 eyes of 9 patients with NVAMD, chronic subfoveal SRF despite continuous anti-VEGF therapy, and good long-term visual acuity of 20/40 or greater were reviewed. Demographic factors, baseline and final visual acuity, neovascular lesion type, duration of persistent fluid, baseline and final subfoveal choroidal thickness, presence of geographic atrophy, and number of anti-VEGF injections were analyzed. Results: The mean age of patients was 78. years (range 55-91). The mean duration of persistent fluid was 5.2. years (range 1.3-11.0). Long-term visual acuities remained stable at 20/40 or better in all eyes. All eyes had type 1 (sub-retinal pigment epithelial) neovascularization. Average baseline subfoveal choroidal thickness was 285.3. μm and the average follow-up subfoveal choroidal thickness was 239.7. μm. No eyes had the presence of geographic atrophy. The mean number of injections was 36.5 (range 17-66). Conclusion: Some eyes with type 1 neovascularization associated with chronic persistent subfoveal subretinal fluid despite continuous intravitreal anti-VEGF therapy may maintain good long-term visual outcomes. We hypothesize that type 1 neovascularization and greater subfoveal choroidal thickness may exert a protective effect on photoreceptor integrity. Further studies are necessary to assess long-term visual prognosis and predictive factors in patients with type 1 neovascularization leading to persistent subretinal fluid that is recalcitrant to anti-VEGF treatment.