AIM:To evaluate the efficacy of intravitreal dexamethasone implant(DEX-I)in the treatment of different types of macular edema secondary to retinal vein occlusion(RVO).

METHODS:A retrospective observational case study was conducted. A total of 46 patients(46 eyes)who were diagnosed with RVO-macular edema(ME)and received DEX-I of 0.7 mg as the initial treatment in Dalian No.3 People's Hospital from July 2019 to June 2020 were collected. According to the morphological characteristics of optical coherence tomography(OCT), they were divided into diffuse retinal thickening type(DRT type, 13 patients, 13 eyes), cystoid macular edema type(CME type, 22 patients, 22 eyes )and serous retinal detachment type(SRD type, 11 patients, 11 eyes ). The best corrected visual acuity(BCVA)and central retinal thickness(CRT)of patients with three types of macular edema were observed and compared before treatment and 1, 2 and 3mo after treatment.

RESULTS:Compared with before treatment, BCVA of patients with DRT, CME and SRD were significantly improved at 1, 2 and 3mo after treatment, and CRT was significantly decreased(all P<0.017). At 3mo after treatment, BCVA(0.21±0.12, 0.22±0.10LogMAR)of DRT and SRD patients was significantly better than that of CME(0.45±0.14LogMAR, both P<0.017), and CRT(254.08±49.07, 248.92±44.19μm)was significantly lower than that of CME(314.70±92.66 μm, both P<0.017).

CONCLUSIONS: DEX-I is effective in the treatment of various OCT types of macular edema secondary to RVO, and the treatment response of CME type is worse than that of DRT and SRD types.