Risk Factors For Neovascular Glaucoma After Vitrectomy In Eyes With Proliferative Diabetic Retinopathy

Objective: To investigate the risk factors for neovascular glaucoma(NVG)after pars plana vitrectomy(PPV)in patients with proliferative diabetic retinopathy(PDR).Methods: This retrospective study including the medical records of 1326patients(1482 eyes)who underwent PPV for PDR at our hospital from January 2014 to December 2019.The following variables were collected:gender,age,diabetes history,diabetes treatment,chronic diseases(including hypertension,coronary atherosclerotic heart disease,diabetic nephropathy,cerebral infarction),blood,urine,coagulation routine and biochemical Indicators(including fasting blood glucose,urine glucose,urine leukocyte,prothrombin activity,blood urea nitrogen,blood creatinine,serum total cholesterol,triglyceride,hemoglobin and serum K+),eye laterality,preoperative eye physical examination(Including visual acuity,intraocular pressure,lens status before PPV,neovascularization in the iris or anterior chamber angle,retinal detachment,vitreous hemorrhage,retinal photocoagulation),whether it is combined with anti-vascular endothelial growth factor(VEGF)therapy during the perioperative period,and whether it is combined cataract phacoemulsification and intraocular lens implantation,types of intraocular fillers,recurrence of vitreous hemorrhage after surgery,history of surgery after PPV,history of surgery on the contralateral eye,whether the contralateral eye is NVG.Analyze the influence of factors on the secondary NVG after PPV.Patients with secondary NVG were divided into two groups according to whether they were combined with anti-VEGF therapy during perioperative period,and the time of NVG after PPV was recorded.Results:1.In univariate analysis,gender,hypertension,diabetic nephropathy,anemia,preoperative vision,fasting blood glucose,urine glucose,prothrombin activity,neovascularization in the iris or anterior chamber angle,retinal detachment,preoperative retinal photocoagulation less than 2 quadrants,recurrent vitreous hemorrhage after surgery,reoperation after PPV are related to the occurrence of NVG after PPV,and the differences were statistically significant(P<0.05).2.Logistic regression analysis on the statistically significant factors which in the univariate analysis shows that male,high fasting blood glucose,anemia,neovascularization in the iris or anterior chamber angle,and postoperative recurrent vitreous hemorrhage are risk factors for NVG after PPV(OR=9.106,P<0.001),(OR=1.196,P=0.020),(OR=10.796,P<0.001),(OR=9.815,P<0.001),(OR=81.660,P<0.001);normal prothrombin activity and preoperative retinal photocoagulation ≥ 2 quadrants are protective factors to prevent secondary NVG after surgery(OR = 0.312,P = 0.022),(OR= 0.197,P<0.001).3.According to the Mann-Whitney test,patients who were treated with anti-VEGF during the perioperative period had longer time to perform NVG after surgery than those without anti-VEGF,the difference was statistically significant(P<0.05).Conclusions: Among the 1325 patients(1482 eyes)with PDR,51(3.4%)eyes developed NVG after PPV.Male,high fasting blood sugar,anemia,neovascularization in the iris or anterior chamber angle,postoperative recurrent vitreous hemorrhage are risk factors for NVG after PPV;normal prothrombin activity and preoperative retinal photocoagulation ≥ 2quadrants are protective factors to prevent secondary NVG after surgery.Perioperative anti-VEGF therapy cannot reduce the incidence of NVG after surgery,but it can delay the occurrence of NVG.