Comparison of intravitreal ranibizumab monotherapy vs. ranibizumab combined with dexamethasone implant for macular edema secondary to retinal vein occlusion

Abstract

PurposeTo compare the efficacy and the injection number of intravitreal ranibizumab (IVR) monotherapy vs. intravitreal ranibizumab plus dexamethasone (IVR + DEX) implants for macular edema (ME) secondary to retinal vein occlusion (RVO).MethodsThis prospective, control trial comprised 96 eyes of 96 patients with ME due to non-ischemic RVO divided into two groups. The IVR monotherapy group consisted of 61 patients (29 with CRVO and 32 with BRVO) treated with ranibizumab with three consecutive loading doses at a monthly + pro re nata (three + PRN) regimen. The IVR + DEX implant group consisted of 35 patients (19 with CRVO and 16 with BRVO) treated with intravitreal ranibizumab plus DEX implant. All eyes underwent best-corrected visual acuity (BCVA, log MAR), central foveal thickness (CFT), and intraocular pressure (IOP). In case of recurrence, each group received initial medication.ResultsAt the 12-month visit, the mean log MAR BCVA that was improved from baseline was 0.23 with the IVR group and 0.30 with the IVR + DEX group. CFT decreased on average by 420 ± 292 μm with the IVR group and 393 ± 259 μm with the IVR + DEX implant group. No significant differences were detected in BCVA improvement and CFT reduction between the two groups (p > 0.05). The mean number of injections was 5.4 in the IVR group and 3.9 in the IVR + DEX implant group (p < 0.001). The mean reinjection interval for patients with the IVR + DEX implant was 131.2 ± 8.9 days (range: 98–150). The incidence of high IOP and cataract progression were significantly higher in the IVR + DEX implant group than in the IVR group (both p < 0.001).ConclusionIn RVO-ME, the IVR + DEX implant did not have synergistic efficacy, providing further improvement in BCVA and a reduction in CFT. However, the IVR + DEX implant still had an advantage in reducing the number of injections and prolonging the time between injections.