Pars Plana Ahmed Implantation Combined with 23-gauge Vitrectomy for Refractory Neovascular Glaucoma in Diabetic Retinopathy

Purpose: To evaluate the efficacy and safety of a pars plana Ahmed valve implantation combined with 23-gauge sutureless vitrectomy in the treatment of patients with medically uncontrolled neovascular glaucoma(NVG) in proliferative diabetic retinopathy (PDR). Methods: The authors retrospectively reviewed the records of 11 consecutive patients with refractory NVG in PDR who underwent a 23-gauge sutureless vitrectomy combined with pars plana placement of an Ahmed valve implant. Control of intraocular pressure (IOP), pre- and postoperative best-corrected visual acuity and the development of intra- and postoperative complications were evaluated during the follow-up. Results: The mean follow-up was 12.2 months (range, 8 to 25 months). Mean preoperative IOP was 35.9 ± 6.3mmHg and mean postoperative IOP at the last visit was 13.3 ± 3.2 mmHg. Control of IOP (8 to 18 mmHg) was achieved in all patients, but 91% (10 of 11 patients) needed antiglaucoma medication (mean number of medications, 1.2 ± 0.6). Postoperative visual acuity improved in 11 eyes, and the logarithmically to the minimum angle of resolution mean visual acuity in these eyes improved from 1.67 ± 0.61 to 0.96 ± 0.67. The complications that occurred were transient hypotony in one case, transitory hypertension in two cases, and postoperative vitreous hemorrhage which spontaneously cleared in two cases. Conclusions: We suggest the combination of 23-gauge pars plana vitrectomy and Ahmed valve implantation is safe and effective in PDR patients with refractory NVG.