Quantification of short-term progression of active neovascular age-related macular degeneration and correlation with 1-year outcome. Sixty-five patients with newly diagnosed treatment-naive active subfoveal choroidal neovascularization (CNV), who had participated in clinical trials testing anti-vascular endothelial growth factor therapy, were retrospectively assessed. Early Treatment Diabetic Retinopathy Study best-corrected visual acuity (BCVA), Spectral Domain Optical Coherence Tomography (SD-OCT) and fluorescein angiography (FA) were performed twice during the pretreatment period. Changes in BCVA, central retinal thickness (CRT), average macular thickness (AMT) and leakage area were documented within this pretreatment period for all patients and for lesion type I (occult CNV, n=42) and type II (classic CNV, n=23). Three-month and 1-year BCVA were then correlated with the pretreatment period. The pretreatment period was 19±3 days (range: 2-108). Neither type I nor type II lesions showed a significant BCVA decrease or CRT/AMT increase during this period. On FA, mean leakage area increased significantly during the pretreatment period: in the pooled group from 5.50±0.62 (screening) to 7.60±0.86 mm2 (baseline) (p<0.0001), in type II from 4.65±0.90 to 7.83±1.62 mm2 (p<0.01) and in type I from 6.08±0.85 to 7.45±0.96 mm2 (p<0.0001). The mean increase in leakage area per day was 0.046±0.02 mm2, p=0.034. Type II showed a daily growth of 0.09±0.08 mm2 (p<0.042) and type I 0.045±0.008 mm2 per day (p<0.0001). However, neither leakage area increase nor pretreatment period was correlated with 3-month or 1-year BCVA outcome. SD-OCT and BCVA testing did not reveal deterioration during the pretreatment period. However, the leakage area progressed rapidly. Despite the rapid increasing leakage area, the 19-day waiting period was not associated with a poorer visual outcome at 3 months and 1 year.