Causes of neovascular glaucoma secondary to proliferative diabetic retinopathy after pars plana vitrectomy

Abstract

Objective To investigate the causes of neovascular glaucoma (NVG) secondary to proliferative diabetic retinopathy (PDR) after pars plana vitrectomy (PPV). Methods A total of 199 patients (203 eyes) with PDR who received PPV treatment in Changzhi People’s Hospital from January 2015 to December 2017 were included in the study. The incidence of NVG in patients treated with anti-vascular endothelial growth factor (VEGF) before PPV was compared with that in patients who were not treated with anti-VEGF; and the incidence of NVG was compared between patients treated by PRP before PPV and patients not treated by PRP. The causes of NVG after PPV were analyzed retrospectively. Results Of the 199 cases (203 eyes), 7 eyes (7 patients, 3.45%) had NVG. Of the 7 patients, 4 patients were treated with anti-VEGF therapy before PPV, and 3 patients were without anti-VEGF therapy; there was no significant difference the between them (P>0.05). NVG occurred in 1 case who had received PRP, and it occured in 6 cases without PRP before PPV treatment, however there was no significant difference between them (P>0.05). In 7 patients with NVG, fundus fluorescein angiography and retinal photocoagulation were not performed in time after operation. Retinal detachment occurred in 1 case and 5 cases had blood glucose instability after operation. Conclusions Retinal photocoagulation during operation, retinal detachment after operation, multiple operations and perioperative blood glucose instability are the main causes of NVG after PPV for PDR. Key words: Diabetic retinopathy; Vitrectomy; Neovascular glaucoma