Subretinal fluid may protect against macular atrophy in neovascular age-related macular degeneration: 5 years of follow-up from Fight Retinal Blindness registry

Purpose: The purpose of the study was to assess the association of macular atrophy (MA) according to the activity of macular neovascularization (MNV) (inactive, only subretinal fluid [SRFL], or active, i.e. including intraretinal fluid [IRFL]) using optical coherence tomography (OCT) in patients with neovascular age-related macular degeneration (nAMD).

Methods: Multicentric observational study. Treatment-naïve nAMD eyes without subfoveal MA or subretinal fibrosis (SF) at baseline were included since 1st January 2010 and 30th September 2016 to allow up to 5 years of treatment follow-up. Eyes were grouped based on their predominant activity status as: (1) mostly inactive, (2) mostly active non-SRFL only [IRFL] or (3) mostly active-SRFL only [onlySRFL]. Kaplan-Meier survival curves estimated the time to development of MA or SF. Cox proportional hazards models evaluated predictors of developing subfoveal MA or SF. The main outcome measure was the risk of developing MA according to predominant MNV activity.

Results: A total of 973 eyes were eligible for analysis. OnlySRFL eyes had lower risk of developing subfoveal MA (HR [95% CI]: 0.56 [0.36, 0.88]; p = 0.024) and extrafoveal MA (HR [95% CI]: 0.41 [0.27, 0.61]; p < 0.001) than IRFL eyes. IRFL eyes had lower visual acuity (VA) (54.5 letters) and the highest proportion of eyes with vision ≤35 letters (25%) at 5 years while onlySRFL eyes had comparable 5-year VA (63.7 letters) to inactive eyes (63.7 letters). Conclusion: Subretinal fluid appears to protect against MA. Distinguishing the compartment of retinal fluid and understanding its relationship with MA and SF can guide the management of nAMD. Keywords: intraretinal fluid; macular atrophy; neovascular age-related macular degeneration; subretinal fibrosis; subretinal fluid.