Background Treatment of neovascular
age-related macular degeneration (nvAMD) under real life conditions may differ from controlled prospective trials with respect to the number of
injections and long term preservation of visual acuity. In many instances, intervals for controls and re-injection cannot be maintained as frequently as required. This case series examines actual intervals for control and re-injection visits, in order to estimate how prolonged intervals have an impact on momentary visual acuity and how long term visual outcome is affected. Patients/Material and Methods Retrospective case series of 1,324 eyes with nvAMD, treated with a total of 8,150
ranibizumab injections (according to the PRN regimen) or 1,725
aflibercept injections (according to a fixed regimen), during the observation period of up to 3 years. The evaluation covered the time interval between visits, impact of this on the course of visual acuity, as well as the number of
injections throughout treatment. Results Planned intervals of 4 or 8 weeks between visits were more often exceeded in the PRN regimen than with the fixed regimen. Visual acuity does not peak after 4 weeks, but only between 6 and 8 weeks. No statistically significant difference between
aflibercept and
ranibizumab was found. If the mean interval for re-injection was maintained at 4 - 6 weeks, this gave the greatest gains in visual acuity at end of years 1 and 2, respectively. Any prolongation of these intervals was accompanied by worse long term visual acuity. The fixed regimen is associated with consistently briefer re-treatment intervals during years 2 and 3, than with the PRN regimen. Conclusion Our data point to the importance of frequent controls accompanied by timely
retreatment, as these have a major impact on visual outcome. It therefore appears to be more important to choose a treatment plan that facilitates frequent re-
injections than to select either of the two compounds.