Microaneurysm Turnover after the Use of Dexamethasone and Bevacizumab to Treat Diabetic Macular Edema

Purpose: To evaluate microaneurysm (MA) turnover and changes in central retinal thickness after intravitreal dexamethasone implantation or intravitreal bevacizumab injection to treat diabetic macular edema. Methods: Sixty eyes with diabetic macular edema were evaluated. In all, 30 eyes received intravitreal dexamethasone implants (group A) and 30 received bevacizumab injections (group B). All patients were followed-up at 3 and 6 months. MA formation, disappearance, and turnover (MA formation rate minus disappearance rate) were evaluated. When the disappearance rate was greater than the formation rate (so the turnover was ≤0), the microaneurysms were considered to have resolved. Central retinal thickness (CRT) was measured using optical coherence tomography at all visits. Results: In group A, MA turnover was 86.6% at 3 months and 53.3% at 6 months, and thus decreased slightly over time, but was not eliminated. In group B, MA turnover was 56.6% at 3 months and 13.3% at 6 months; the between-group difference was statistically significant (p = 0.014). CRT decreased in both groups, but significantly less so in group B 3 months after injection. However, no significant between-group difference was apparent 6 months after injection. Conclusions: There were no significant between-group differences in either CRT or MA turnover 3 months after injection. However, at 6 months, dexamethasone implantation showed slightly better results than intravitreal bevacizumab injection. However, further research on long-term MA turnover is required. J Korean Ophthalmol Soc 2018;59(4):332-337