A RANDOMIZED PAIRED-EYE TRIAL OF INTRAVITREAL DEXAMETHASONE IMPLANT FOR CYSTOID MACULAR EDEMA IN RETINITIS PIGMENTOSA

To evaluate the efficacy and safety of intravitreal dexamethasone (DEX) implant in retinitis pigmentosa patients with cystoid macular edema (CME).In this randomized, noncontrolled, paired-eye, single crossover clinical trial, one eye of retinitis pigmentosa patients with bilateral CME with central macular thickness of250 µm was randomized to intravitreal DEX implant while the fellow eye was observed. Both eyes were started on topical dorzolamide. At Month 6, DEX implant was eligible for both eyes when CME was250 µm. Patients were followed up until Month 12. Primary outcome measures were the central macular thickness and best-corrected visual acuity changes from baseline at Month 2.Fourteen patients with bilateral RP-CME were included. Study eyes showed significant central macular thickness decrease (median, -147.5 µm; P = 0.001) and best-corrected visual acuity improvement (median, +6 letters; P = 0.001) at Month 2, but not at Month 6. Intravitreal DEX implant at Month 6 produced comparable efficacy to baseline treatment in 11 fellow eyes and 12 study eyes. Topical dorzolamide did not show significant therapeutic efficacy. During 12 months, elevated intraocular pressure of21 mmHg and cataract progression were observed in 14.3% and 40.0% of study eyes.Intravitreal DEX implant can both reduce macular thickness and improve vision in RP-CME, while repeated injection is required.