Valved Glaucoma Drainage Devices in Pediatric Glaucoma: Retrospective Long-term Outcomes.

IMPORTANCE Relatively little data exist about the long-term outcomes of an initial glaucoma drainage device (GDD) and subsequent GDDs implanted in pediatric patients with glaucoma. OBJECTIVE To determine the long-term outcomes of the first and second GDDs and risk factors in pediatric glaucoma. DESIGN, SETTING, AND PARTICIPANTS Retrospective review of 119 eyes of 89 patients younger than 18 years with glaucoma who underwent valved GDD implantation from March 1999 to April 2012 at the Stein Eye Institute, University of California, Los Angeles. EXPOSURE Implantation of GDD, using silicone and polypropylene Ahmed glaucoma valve. MAIN OUTCOMES AND MEASURES Kaplan-Meier survival analysis and risk factors associated with GDD failure. Success was defined as a final intraocular pressure of 5 to 21 mm Hg as well as a 20% reduction from baseline intraocular pressure with or without medications. RESULTS The mean (SD) age at implantation of the first GDD was 6.8 (5.7) years. The mean (SD) follow-up time was 6.1 (3.3) years from surgery. The mean intraocular pressure was reduced by 13.0 mm Hg (95% CI, 8.8 to 17.3 mm Hg) at 5 years postoperatively. The mean number of glaucoma medications preoperatively vs postoperatively was not different starting at 5 years (reduction of 0.5; 95% CI, -0.1 to 1.0). The success rate at 5 years was 55.0% (95% CI, 46.0% to 65.9%). Risk factor analysis suggests that older age (risk ratio = 0.95; 95% CI, 0.90 to 0.99; P = .02), uveitic glaucoma (risk ratio = 0.34; 95% CI, 0.14 to 0.86; P = .02), and polypropylene GDDs (risk ratio = 0.39; 95% CI, 0.23 to 0.67; P = .001) were associated with higher success rates. Thirty-six eyes received a second GDD, with a mean (SD) of 2.2 (1.6) years between the 2 operations. The success rate 5 years after the second surgery was 52.8% (95% CI, 37.0% to 75.3%). Risk factors associated with failure of the first GDD were not found to affect the likelihood of failure for the second. CONCLUSIONS AND RELEVANCE Glaucoma drainage devices, such as the Ahmed glaucoma valve, have moderate long-term success rates in pediatric patients with glaucoma. In pediatric patients, the first GDD is successful in 46% to 70% of patients at 5 years with medications, and the second GDD is successful in 37% to 75% of patients at 5 years after the subsequent surgery.