Most retina specialists use a treat-and-extend approach for wet age-related macular degeneration (AMD), whereby anti–vascular endothelial growth factor (VEGF) injections are performed until the retina is dry and then the treatment interval between injections is gradually prolonged, with the goal of maintaining this effect. However, we know from clinical trials that achieving a retina with no macular fluid is not possible in all patients. The proportion of patients with no fluid at 2 years was 45.5% and 60.3% with monthly ranibizumab in the CATT and VIEW studies, respectively, and 80.3% with monthly aflibercept in the VIEW study.
Thus, there is increasing discussion about whether residual fluid matters in AMD. And there are also questions about which of the various subtypes of retinal fluid — intraretinal fluid or cysts, subretinal fluid, and subretinal pigment epithelium fluid — are the most likely to negatively affect visual acuity outcomes.
Subanalyses from both the CATT and HARBOR[1] studies found that patients with intraretinal fluid, especially if located in the fovea, had worse visual acuity than those with subretinal or subretinal pigment epithelium fluid. Conversely, patients with subretinal fluid in the fovea had better visual acuity than those without.
The prospective, randomized FLUID studyprovided additional information of value by assessing whether subretinal fluid can be safely tolerated in patients with exudative AMD being treated with anti-VEGF therapy.
