Early persistent retinal fluid during treatment of neovascular AMD with ranibizumab and aflibercept

Age-related macular degeneration (AMD) is the leading cause of irreversible vision loss in subjects aged >65 years living in economically developed countries (1,2). As birthrates drop and life expectancy rises, the prevalence of AMD is expected to increase, along with the social and economical burden associated with the disease and its treatment. Anti-vascular endothelial growth factor (VEGF) drugs have revolutionized the management of neovascular AMD (nAMD) and are now considered the mainstay of therapy (1,3). Although monthly injections seem to produce the best functional results according to clinical trials (4-7), the increasing patient numbers and exponentially growing costs made it clear that alternatives should be sought for a clinical practice setting. To this day, plentiful controversies still exist over the best available drug and treatment regimen for the management of nAMD. Variations in patient response to anti-VEGF therapy have been identified in clinical trials, regardless of the drug or regimen used. Understanding the reasons (epidemiological, genetic, functional, anatomical, etc.) behind these variations could help predict the injection requirements of individual patients, thus reducing unnecessary visits and preventing over- or undertreatment (8). Although most patients respond rapidly to anti-VEGF treatment, residual fluid on OCT persists in a subgroup of eyes across clinical trials of different drugs and regimens. Since treatment decisions are often driven by the presence of fluid on OCT, the quest for imaging biomarkers capable of predicting the functional and anatomical prognosis became the goal of several investigators.