Long-term results of Ahmed glaucoma valve implantation in Egyptian population

AIM: To evaluate the long-term results and complications of Ahmed glaucoma valve (AGV) implantation in a cohort of Egyptian patients. METHODS: A retrospective study of 124 eyes of 99 patients with refractory glaucoma who underwent AGV implantation and had a minimum follow-up of 5y was performed. All patients underwent complete ophthalmic examination and intraocular pressure (IOP) measurement before surgery and at 1d, weekly for the 1st month, 3, 6mo, and 1y after surgery and yearly afterward for 5y. IOP was measured by Goldmann applanation tonometry and/or Tono-Pen. Complications and the number of anti-glaucoma medications needed were recorded. Success was defined as IOP less than 21 mm Hg with or without anti-glaucoma medication and without additional glaucoma surgery. RESULTS: Mean age was 23.1±19.9y. All eyes had at least one prior glaucoma surgery. IOP was reduced from a mean of 37.2±6.8 to 19.2±5.2 mm Hg after 5y follow-up with a reduced number of medications from 2.64±0.59 to 1.81±0.4. Complete and qualified success rates were 31.5% and 46.0% respectively at the end of follow-up. The most common complications were encapsulated cyst formation in 51 eyes (41.1%), complicated cataract in 9 eyes (7.25%), recessed tube in 8 eyes (6.45%), tube exposure in 6 eyes (4.8%) and corneal touch in 6 eyes (4.8%). Other complications included extruded AGV, endophthalmitis and persistent hypotony. Each of them was recorded in only 2 eyes (1.6%). CONCLUSION: Although refractory glaucoma is a difficult problem to manage, AGV is effective and relatively safe procedure in treating refractory glaucoma in Egyptian patients with long-term follow-up. Encapsulated cyst formation was the most common complication, which limits successful IOP control after AGV implantation. However, effective complications management can improve the rate of success.