Dynamic Analysis of Ocular Fundus Changes After Different Doses of Bevacizumab in the Treatment of Retinopathy of Prematurity in Threshold Period

Abstract Purpose : To analyze the efficacy of three different doses of bevacizumab treatment on Threshold retinopathy of prematurity during different periods . Methods : 36 cases (72 eyes) of infants with threshold ROP were analyzed, whom were treated with intravitreal injection of 1.25 mg, 0.75 mg or 0.5 mg bevacizumab respectively from October 1 st , 2016 to September 30 th , 2017. After treatment, fundus examination results during five time points were recorded and classified into four grades according to the efficacy. Results : There were significant differences in the changes of fundus among the 3 groups from the 4 th day to the 4 th week after treatment （P<0.01）. In the 1.25 mg group, there was a significant difference in the changes of fundus on the 4 th day after treatment VS. the 2 nd week after treatment (P<0.001). In the 0.75 mg and 0.5 mg group respectively, the changes of fundus were significantly different between each consecutive time points of the 4 th day, 2 nd week, 4 th week and 2 nd month after treatment (P<0.001,P=0.001,P=0.002; P<0.001,P=0.001,P=0.003). The proportion of normal retinal vessels respectively in 1.25 mg , 0.75 mg and 0.5 mg group is 66.67%、43.48% and 50% in the 3rd month after treatment. Conclusion : Retinal complete vascularization was slightly better in 1.25 mg group, but failed to reach a statistical significance. Based on results, the lowest dose 0.5 mg may be preferred since our final results were similar (p>0.05). Long-term follow-up of fundus changes was still needed to avoid recurrence of ROP whatever the dose of bevacizumab was uesed.