Fibrovascular proliferation of retinopathy of prematurity in zone II after initial ranibizumab treatment

This study was designed to explore the prevalence of fibrovascular proliferation not regressed in zone II stage 3 retinopathy of prematurity (ROP) after initial intravitreal ranibizumab (IVR) injections and to explore the possible influence factors. Fifty-seven patients (108 eyes) with ROP who underwent intravitreal injection of ranibizumab between January 2013 and July 2014 participated in the retrospective study. Based on regress of fibrovascular tissue or not after initial injections of ranibizumab, eligible eyes were divided into two groups. Data was collected and analyzed with SPSS 16.0. In the study, 108 eyes of 57 patients (18 females, 39 males) underwent initial intravitreal injection. The mean birth weight was 1,440.0±357.7 g and the mean gestational age was 30.5±2.0 weeks. Eight of 57 (14.0%) patients showed unfavorable fibrovascular proliferation after initial ranibizumab treatment within 2 weeks. Among them, 11 eyes were controlled by further laser treatment and 3 eyes underwent vitrectomy. The difference of occurrence rate in hemorrhage between the two groups was significant (P<0.030), and the unfavorable group required more laser treatment (P<0.001). The incidence of unfavorable fibrovascular proliferation was relatively high, and intraocular hemorrhage was possibly associated with the progress in zone II stage 3 ROP after initial IVR injection.