Central Retinal Thickness Variability as a Predictive Factor for Visual Acuity After Dexamethasone Implant in Retinal Vein Occlusion

BACKGROUND AND OBJECTIVE: Investigate central retinal thickness (CRT) variability and changes in best-corrected visual acuity (BCVA) after 12 months in patients with retinal vein occlusion (RVO) treated with dexamethasone intravitreal implants. PATIENTS AND METHODS: Post hoc analyses of two randomized trials in patients with macular edema associated with branch or central RVO treated with a 0.7-mg dexamethasone implant. Central retinal thickness standard deviation (CRT-SD) and central retinal thickness amplitude (CRT-A) were measures of variability. Analyses included multinomial and simple linear regression. RESULTS: In 400 patients, CRT-SD and CRT-A were significantly associated with central RVO, second dexamethasone implant, and baseline CRT. Baseline BCVA was associated with CRT-A. CRT-SD and CRT-A were significantly correlated with a 12-month change in BCVA (effect sizes of -0.032 and -0.013 letters/mu m; P < 0.001). Patients in the highest CRT-SD quartile gained significantly fewer letters (+1.88 letters; 95% CI: -0.46 to 4.23). CONCLUSION: Greater CRT variability was associated with smaller BCVA improvements in patients with RVO treated with dexamethasone implants.