Long term comparison between single stage Baerveldt and Ahmed glaucoma implants in pediatric glaucoma

Purpose: To compare the long term intraocular pressure control in pediatric glaucoma patients who underwent single stage Baerveldt glaucoma valve and Ahmed glaucoma valve S2 implantation. Study design: A retrospective study was conducted to analyze the data of patients with single stage Baerveldt glaucoma valve and Ahmed valve implantation at Children Hospital Los Angeles. Methods: Medical records of patients were reviewed retrospectively and divided into two groups. All cases received single stage valve implantation in which the tube was inserted primarily into the anterior chamber. In cases with Baerveldt implants, the silicone tube was ligated near its plate location with a single absorbable suture. Group 1 included patients with Baerveldt glaucoma implant model BG 101-350, while group 2 included patients with Ahmed valve implant model S-2. Patients' data collected ranged over the period from 2001 to 2008. The minimum follow up period was 6 month; maximum follow up period was 8 years. All patients were below 18 years of age. Success was considered if last postoperative IOP was between 8 and 24 mm Hg (with or without medications), no additional glaucoma surgery after valve implantation, and absence of visually significant complications. Results: Group 1 included 20 cases and group 2 included 11 cases. Long term success rate based on criterion defined was 80% for group 1 (Baerveldt) with average IOP postoperatively on last follow-up of 19.6 mm Hg. In group 2 (Ahmed), average postoperative pressure was 24 mm Hg with 6 out of 11 considered successful based on criterion giving 54.5% success rate. Conclusion: In the long term, single stage Baerveldt implantation appears to control pressure well in pediatric glaucoma.