AIM:To evaluate the therapeutic efficacy of intravitreal injections of ranibizumab for macular edema secondary to retinal vein occlusion(RVO)and the prognostic factors for this disorder.

METHODS:A retrospective case study. There were 61 patients(61 eyes)with macular edema secondary to RVO who treated in our hospital from April 2020 to February 2021, including 30 cases(30 eyes)of branch retinal vein occlusion(BRVO)patients and 31 cases(31 eyes)of central retinal vein occlusion(CRVO)patients. All patients received 3 times of intravitreal injections of ranibizumab(0.5mg), and some eyes underwent retinal laser therapy. The patients were followed up for 3mo after treatment(the first intravitreal injection)to observe the visual acuity, intraocular pressure, central retinal thickness(CRT)and record the occurrence of ocular and systemic complications.

RESULTS: The visual acuity of the included patients after treatment was significantly improved compared with that before treatment, and the CRT was significantly decreased compared with that before treatment(P<0.01), and after 3 times of intravitreal injections, the visual acuity of BRVO and CRVO patients with pre-treatment visual acuity≤1(LogMAR)was better than that of the patients with pre-treatment visual acuity>1(P<0.01), but there was no difference in CRT(all P >0.05). Among BRVO and CRVO patients, 12 and 8 eyes received retinal laser treatment during 3 times of intravitreal injections, respectively. The difference in visual acuity and CRT among the eyes treated with laser and those that were untreated was not significant(P>0.05). No ocular and systemic serious complications emerged during follow-up.

CONCLUSIONS: Ranibizumab has high efficacy and safety in the treatment of macular edema secondary to RVO, while visual acuity at baseline may help predict the prognosis.