Effect of Intravitreal Anti-Vascular Growth Factor Agents With or Without Macular Photocoagulation on Diabetic Macular Edema: A Systematic Review and Meta-Analysis

IntroductionDiabetes is a common cause of new sight loss in populations world-wide, and diabetic macular edema (DME) is a major cause of visual deficits in the diabetic populations of developed countries. We have performed a meta-analysis to evaluate whether combined treatment with anti-vascular endothelial growth factor (VEGF) injections and macular photocoagulation (MPC) is more efficacious than primary monotherapy with anti-VEGF injections in patients with DME.MethodsWe systematically searched the PubMed and Web of Science databases for studies providing sufficient information for a comparison of pre- and post-treatment of central macular thickness (CMT) and best-corrected visual acuity (BCVA) between two groups of patients with DME given interventional therapies (monotherapy with an anti-VEGF agent vs. combination therapy with an anti-VEGF agent and MPC) before January 2019. A meta-analysis was performed to summarize the results of the studies included in the systematic review.ResultsThe results of our meta-analysis indicated that post-treatment CMT was significantly lower at 3months in DME patients receiving combination therapy with bevacizumab, a humanized anti-VEGF antibody, and MPC than in those receiving monotherapy with bevacizumab. The results also showed that post-treatment CMT was lower in DME patients given ranibizumab, an anti-VEGF agent, in combination with MPC at 6, 9 and 12months than in those treated with ranibizumab alone. However, no significant differences were found in post-treatment BCVA at 1, 3, 6, 9 and 12months between DME patients receiving combination therapy with an anti-VEGF agent (bevacizumab or ranibizumab) and MPC and those receiving monotherapy with an anti-VEGF agent.ConclusionIn conclusion, the results of our meta-analysis demonstrate a transiently synergistic effect of MPC on CMT when this treatment is combined with anti-VEGF agents, whereas no similar synergistic effect could be detected on the BCVA. A relatively longer follow-up was essential to be able to evaluate the long-term existence of this synergistic effect.