Neovascular Glaucoma after Vitrectomy for Proliferative Diabetic Retinopathy and the Ahmed Valve Implantation

ABSTRACT

PURPOSE: To evaluate the clinical features of neovascular glaucoma after vitrectomy for proliferative diabetic retinopathy and the effect of Ahmed valve implantation. METHODS: The medical records of 217 eyes of 178 patients who had undergone pars plana vitrectomy for proliferative diabetic retinopathy were reviewed. The clinical data on preoperative, intraoperative, and postoperative factors of these patients were compared with that of those who developed neovascular glaucoma (20 eyes of 18 patients) after vitrectomy. The effect and complications of Ahmed valve implantation were also reviewed. RESULTS: The type 1 diabetes, the presence of NVD, grade of NVE, grade of preoperative PRP, presence of postoperative vitreous hemorrhage, and postoperative tractional retinal detachment were significantly correlated with the development of neovascular glaucoma. Ahmed valve implantation in these patients was effective in controlling intraocular pressure and improving visual acuity. Complications of the Ahmed valve implantation were hyphema, tube exposure, recurrent vitreous hemorrhage, hypotony, and choroidal effusion. CONCLUSIONS: The risk factors for the development of neovascular glaucoma after vitrectomy for proliferative diabetic retinopathy were evaluated. Ahmed valve implantation in these patients is considered an effective treatment for controlling intraocular pressure.