Abstract:

Objective To observe the concentration of the vascular endothelial growth factor (VEGF)-A, VEGF-B and placental growth factor(PIGF) in aqueous humor ,vitreous and neovascular membrane of proliferative diabetic retinopathy (PDR) and the safety of vitrectomy after intravitreal ranibizumab injection(IVR). Design Prospective study. Participants A total of 60 PDR patients (60 eyes) were enrolled in this study from January 2015 to October 2016 in Shanxi Eye Hospital. Methods The patients were randomly divided into pars plana vitrectomy (PPV) group and IVR combined with PPV group, 30 eyes in each group. Samples of aqueous humor, vitreous and neovascular membrane were collected in the PPV group. Samples of aqueous humor were collected before IVR and samples of vitreous and neovascular membrane on 7th day after IVR during PPV in the IVR combined with PPV group. The concentrations of VEGF-A, VEGF-B and PIGF in the aqueous humor and vitreous were measured with enzyme linked immunosorbent assay (ELISA). The expression of VEGF-A, VEGF-B and PIGF in the proliferative membrane was also studied with immunohistochemistry method. The number of blood vessels in the proliferative membrane was observed with haematoxylin and eosin (HE) stains. The surgical time, severity of intraoperative bleeding between the two groups was observed. Main Outcome Measures The contents of VEGF-A, VEGF-B and PIGF in aqueous humor, vitreous and proliferating membrane were observed. The operation time and intraoperative bleeding were observed. Results The VEGF-A concentration (108.30±27.13) after IVR was significantly lower than that before IVR (384.84±114.17) (P=0.000) in the aqueous humor. There was no significant difference between VEGF-B and PIGF before and after IVR (all P>0.05). The levels of VEGF-A in the aqueous humor, vitreous and proliferative membrane on 7th day after IVR in IVR combined with PPV group were significantly lower than those in the PPV group (all P<0.05). There was no significant difference in VEGF-B and PIGF (all P>0.05). Compared with the PPV group, the number of blood vessels, the degree of intraoperative blood and the operation time in IVR combined with PPV group were significantly lower (all P<0.05). Conclusion Ranibizumab significantly decreased VEGF-A concentration, the number of blood vessels in the proliferative membrane, the surgical time, severity of intraoperative bleeding, which improved surgical safety and reduced postoperative complications. However, the content of VEGF-B and PIGF loss in aqueous humor, vitreous and proliferative membrane was not obvious. (Ophthalmol CHN, 2018, 27: 258-263)

Key words: diabetic retinopathy, angiogenesis inhibitors, vascular endothelial growth factor family, vitrectomy surgery