The efficacy of intravitreal conbercept for macular edema secondary to retinal vein occlusion

Objective To investigate the effects of intravitreous injection of conbercept for macular edema secondary to retina1vein occlusion(RVO) during 6 months period. Methods A retrospective clinical study. 34 patients (34 eyes) were included in this study, who were diagnosed with macular edema due to retinal vein occlusion by ophthalmologic examination, fundus photography, optical coherence tomography (OCT), fundus fluorescein angiography and other methods. The best corrected visual acuity (BCVA) was examined using the international standard visual acuity chart, and the results were converted to the logMAR visual acuity. The average logMAR BCVA was 0.90±0.68, and the mean macular central retinal thickness (CMT) was (672.27±227.51) μm before treatment. All subjects received intravitreal injection of 0.5 mg conbercept (0.05 ml) at the first visit. Injections were repeated based on the visual acuity changes and the OCT findings. 34 eyes received 69 times of injection, the average number of injections was 2.03±1.03. BCVA, OCT were examined before and after treatment using the same method. BCVA and CMT changes, drugs and treatments associated cardiac and cerebral vascular accident, intraocular pressure elevation, retinal tears, retinal detachment, endophthalmitis and other complications after treatment were observed. Linear correlation analysis was used to analyze the correlation between prognosis BCVA and baseline BCVA, correlation between prognosis BCVA and baseline CMT, and also correlation between BCVA and CMT at different time points before and after treatment. Results At 1 week and 1, 2, 3, 6 months after treatment, the average logMAR BCVA was 0.65±0.61, 0.56±0.61, 0.46±0.55, 0.56±0.71, 0.44±0.48 respectively. During 1, 2, 3, 6 months after treatment, the mean logMAR BCVA were improved with statistically significant difference (Z=34.029, 47.294, 41.338, 43.603; P 0.05). At 1 week and 1, 2, 3, 6 months after treatment, the average CMT was (285.89±96.69), (256.65±143.39), (278.68±156.92), (290.11±188.17), (217.15±48.04) μm respectively. At 1 week and 1, 2, 3, 6 months after treatment, the mean CMT were all decreased with statistically significant difference (Z=68.500, 98.735, 93.235, 91.132, 109.162; P 0.05). Before and 3, 6 months after treatment, BCVA was negatively correlated with CMT (r=0.491, 0.416, 0.386; P 0.05). Systemic adverse reactions and persistent intraocular pressure elevation, iatrogenic cataract, retinal detachment, retinal tear, endophthalmitis and ocular complications were never found in the follow-up period. Conclusion Intravitreal conbercept is a safe and effective approach for RVO, which can significantly improve visual acuity and reduce CMT. Key words: Retinal vein occlusion/drug therapy; Macular edema /drug therapy; Angiogenesis inhibitors/therapeutic use; Antibodies, monoclonal/therapeutic use; Tomography, optical coherence