INITIAL CLINICAL-EXPERIENCE WITH THE AHMED GLAUCOMA VALVE IMPLANT IN PEDIATRIC-PATIENTS

Objective: To evaluate the Ahmed Glaucoma Valve implant, an aqueous sh unting device with a unidirectional valve mechanism, in patients young er than 18 years. Design: Prospective case series. Setting: Tertiary c are hospital. Patients: Twenty-one consecutive patients younger than 1 8 years. The median age of patients was 4.8 years (range, 0.23-17.9 ye ars). Intervention: Placement of an Ahmed Glaucoma Valve implant betwe en April 1992 and April 1994. Main Outcome Measure: Time after surgery without failure. Success was defined as an average intraocular pressu re less than 22 mm Hg for the last 2 follow-ups in eyes with preoperat ive intraocular pressure greater than 22 mm Hg, or an intraocular pres sure that was lowered by at least 20% from preoperative values in eyes with preoperative intraocular pressure less than 22 mm Hg, and no add itional glaucoma surgeries or visually devastating complications. Resu lts: Cumulative probabilities of success at 12 and 24 months were 77.9 %+/-8.8% and 60.6%+/-13.7%, respectively. One eye had a flat anterior chamber and suprachoroidal hemorrhage on the first postoperative day. No other eyes had flat or shallow anterior chambers that required refo rmation. In 3 eyes the implant extruded from underneath the conjunctiv a and was removed. In 2 other eyes the average intraocular pressure fo r the last 2 follow-ups was greater than 22 mm Hg. In 1 eye with an in traocular pressure less than 22 mm Hg preoperatively, the intraocular pressure was not reduced by at least 20%, although the number of antig laucoma medications was reduced. Conclusion: The 12- and 24-month succ ess rates of the Ahmed Glaucoma Valve implant are similar to those of other implants when used in a pediatric population.