Since the mid-1980s, center-involved diabetic macular edema (CI-DME) was primarily treated by laser photocoagulation. This began to change approximately a decade ago, when multiple trials demonstrated that anti–vascular endothelial growth factor (VEGF) agents achieved superior visual outcomes to focal/grid laser therapy in patients with CI-DME. Importantly, these positive results were achieved in patients with CI-DME with reduced visual acuity (VA). The proper management strategy for CI-DME with good VA, however, remained unknown.
To bring some much-needed clarity to this question, the Diabetic Retinopathy Clinical Research (DRCR) Retina Network evaluated three different treatment strategies in 702 eyes with CI-DME and VA of 20/25 or better. Patients meeting inclusion criteria were randomly assigned to receive intravitreal aflibercept (2.0 mg) every 4 weeks, laser photocoagulation therapy every 13 weeks, or observation, and were followed for 2 years.
If the VA decreased by one line on an eye chart at two consecutive visits or two lines at one visit, patients in the photocoagulation and observation groups were started on aflibercept. The primary outcome was a five-letter or greater VA decrease from baseline.
At 2 years, the percentage of eyes with at least a five-letter VA decrease was 16%, 17%, and 19% in the aflibercept, laser photocoagulation, and observation groups, respectively, with no statistically significant differences among the groups.
