Purpose: To evaluate the effect of pars plana implantation of the Ahmed glaucoma valve on refractory glaucoma.
Method: Five patients (5 eyes) (3 men, 2 women) were fitted with the Ahmed glaucoma valve. Mean age was 51.8 21.3 years, and mean follow-up was 9.4 +/- 2.6 months. Among the 5 eyes studied, 4 eyes were in neovascular glaucoma patients. Of these 4 eyes, 2 eyes were in diabetic retinopathy patients and 2 eyes were in a patient with central retinal vein occlusion. The remaining eye was in a developmental glaucoma patient. As a surgical procedure after pars plana vitrectomy, the inlet tube of the Ahmed glaucoma valve was placed in the posterior chamber.
Result: The mean preoperative IOP of 46.8 +/- 15.7 mmHg (30-64 mmHg) under maximum tolerable medication was reduced to 16.0 +/- 2.0 mmHg (14-19 mmHg) after surgery. Postoperative visual acuity improved in 3 eyes, and the mean visual acuity in these eyes improved from 0.05 +/- 0.09 (sl.-0.07) to 0.17 +/- 0.3(0-0.7). A reduction in visual acuity was observed in 2 eyes; in one, due to retinal detachment, and in the other, due to transient high IOP and vitreous hemorrhage. The visual acuity improved in 60% of patients and the IOP controlled in 80% of patients.
Conclusion: The implantation of the Ahmed glaucoma valve for refractory glaucoma was effective in our study.