Effect of the duration of macular edema on clinical outcomes in retinal vein occlusion treated with dexamethasone intravitreal implant

Abstract

Purpose: To assess the effect of duration of macular edema (ME) on clinical outcomes after treatment with dexamethasone intravitreal implant 0.7 mg (Ozurdex; Allergan, Inc, Irvine, CA) in patients with ME following branch retinal vein occlusion (BRVO) or central retinal vein occlusion (CRVO). Design: Post hoc analysis of pooled data from 2 randomized, controlled trials. Participants: Patients with vision loss resulting from ME of 6 weeks' duration or more after BRVO or CRVO (n = 690). Methods: The relationship between ME duration at the time of first treatment and treatment outcomes was assessed using logistic regression. Other factors potentially associated with ME duration or patient outcomes were adjusted for in the analyses. Main Outcome Measures: The proportion of patients achieving at least 15 letters improvement in best-corrected visual acuity (BCVA) or at least 200-μm or more reduction in central retinal thickness 6 or 12 months after the first treatment with dexamethasone intravitreal implant 0.7 mg. Results: In the 6-month analysis, each 1-month increase in ME duration was associated with a significantly lower likelihood of achieving a BCVA improvement of 15 letters or more (odds ratio [OR], 0.88; 95% confidence interval [CI], 0.83-0.94; P