Comparison of Mitomycin C Trabeculectomy and Ahmed Valve Implant Surgery for Neovascular Glaucoma

PURPOSE: To compare the results of mitomycin C trabeculectomy and Ahmed valve implant surgery for neovascular glaucoma (NVG). METHODS: We reviewed the medical records of 58 patients (66 eyes) with NVG who had undergone mitomycin C trabeculectomy or Ahmed valve implant surgery in the previous 5 years. Trabeculectomy (A group) was performed in 27 eyes of 24 patients and valve implant surgery (B group) in 39 eyes of 34 patients. Intraocular pressure (IOP), visual acuity, complications and the rate of surgical success of the two groups were compared. IOP under 21 mmHg without medication was considered as complete success (CS), under 21 mmHg with medication as qualified success (QS), and IOP over 22 mmHg despite medication as failure (F). RESULTS: IOP at postoperative 2 months was lower in the trabeculectomy group than in the drainage implant surgery group (16.4 +/- 11.3 mmHg, 20.9 +/- 8.7 mmHg, P=.087), but at 12 months, there was no statistically significant difference (18.4 +/- 11.5 mmHg, 17.0 +/- 6.4 mmHg, P=.608). Visual acuity also showed no significant difference. The respective rate of success between A and B groups was 66.7% and 38.5% (CS), 25.9% and 33.3% (QS), and 7.4% and 28.2% (F), at postoperative 2 months, and 47.8% and 42.3% (CS), 30.4% and 46.2% (QS), and 21.7% and 11.5% (F), at 12 months. The most common postoperative complication was hyphema in both groups, while other complications were shallow anterior chamber, valve problems, etc. CONCLUSIONS: The type of surgery had no significant effect on the success rate of neovascular glaucoma treatment at postoperative 12 months.

Scleral Allograft with Autologous Buccal Mucosal Transplantation for Tube Erosion Ocurred after Ahmed Glaucoma Valve Implant Surgery: Three Cases

After Drainage implant surgery, erosion of conjunctiva or cornea over tube can occur about 5%in late postoperative period. Scleral allograft for exposed tube should be used to prevent secondary infection. We report three glaucoma patients treated graft with autologous buccal mucosal transplantation for recurrent tube exposure. First case was a 68-year-old male patient with neovascular glaucoma due to central retinal vein occlusion. Second case was a 37-year-old female patient with pseudophakic glaucoma. Third case was a 70-year-old male patient with diabetic neovascular glaucoma. Ahmed glaucoma valve implant surgeries were done for three patients. For tube exposure, we used autologous buccal mucosal transplantation. There was no recurrent erosion and intraocular pressure was maintained well more than 6 months of follow-up. In cases for tube exposure, we introduce that autologous buccal mucosal transplantation can be used to treat tube exposure.