Clinical outcomes of Ahmed glaucoma valve implantation in pediatric glaucoma

Purpose: To evaluate the outcomes of Ahmed glaucoma valve implantation in refractory primary congenital glaucoma as well as primary procedure in aphakic glaucoma. Method: In this retrospective study, medical records of patients who underwent Ahmed glaucoma valve implantation for refractory glaucoma and aphakic glaucoma were reviewed. Primary outcome measures were the surgical success defined as intraocular pressure ≤21 mm Hg and decreased ≥20% and no secondary glaucoma surgery. Secondary outcome measures were the number of glaucoma medications, complications, best corrected visual acuity, and intraocular pressure. Results: A total of 62 eyes of refractory primary congenital glaucoma patients (group 1) and 33 eyes of aphakic glaucoma patients (group 2) were included in our study. Mean follow-up was 51 ± 33 months in group 1 and 49 ± 41 months in group 2 (p = 0.82). The cumulative probability of success was 90% in both groups at the first year; however, the success rate was 52.5% in group 1 and 71.5% in group 2 at 5 years’ follow-up visit. In group 1, the mean intraocular pressure ± standard deviation was 33.1 ± 8.6 mm Hg at the baseline and decreased to 17.1 ± 5.3 mm Hg at 1 year and 18.5 ± 6.4 at 3 years postoperatively (all p’s < 0.001). Corresponding values for group 2 were 28.9 ± 6.1, 15.2 ± 4.6, and 16.0 ± 5.9 mm Hg, respectively (all p’s < 0.001). The baseline number of glaucoma medications was 3 ± 0.7 that decreased to 2 ± 0.8 at final follow-up (p = 0.02). Conclusion: Ahmed glaucoma valve implantation has a moderate success rate in the management of refractory primary congenital glaucoma with an increased chance of tube-related complications. The surgical success rate is higher in case of primary Ahmed glaucoma valve implant for aphakic glaucoma with acceptable safety profile.