Ahmed and Baerveldt Glaucoma Drainage Devices in Childhood Glaucoma: A Meta-Analysis

Précis: The effectiveness of Ahmed glaucoma valve (AGV) and Baerveldt glaucoma implant (BGI) was comparable in the management of childhood glaucoma over the long term despite initial better success rate with BGI. There were higher tube block and retraction rates in the BGI group and higher tube exposure rates in the AGV group. Purpose: To evaluate the outcomes and safety of AGV and BGI in childhood glaucoma. Materials and Methods: We performed a systematic literature review of publications from 1990 to 2022 in PubMed, EMBASE, ClinicalTrials.gov, Ovid MEDLINE, Cochrane CENTRAL, and google scholar for studies evaluating AGV and BGI in childhood glaucoma. Primary outcome measures were intraocular pressure (IOP) reduction and glaucoma medication reduction. The secondary outcome measures were the success rates and incidence of postoperative complications. We conducted a meta-analysis using a random effects model. Results: Thirty-two studies met the inclusion criteria. A total of 1480 eyes were included. The mean IOP reduction was 15.08 mm Hg (P < 0.00001) for AGV and 14.62 (P < 0.00001) for the BGI group. The mean difference between pre and postoperative glaucoma medications was 1 (P < 0.00001) fewer medications in the AGV group and 0.95 (P < 0.0001) fewer medications in the BGI group. There was a lower success rate in the AGV versus BGI groups at 2 years [63% vs 83%, respectively (P < 0.0001) and 3 years (43% vs 79%, respectively (P < 0.0001)]; however, the success was higher for AGV at 5 years (63% vs 56% in the BGI group, P < 0.001). The incidence of postoperative complications was comparable in the AGV and BGI groups, with rates of 28% and 27%, respectively. Conclusions: The IOP and glaucoma medication reduction, success rates, and incidence of postoperative complications were comparable in Ahmed and Baerveldt groups. Most literature comes from retrospective low-quality studies on refractory childhood glaucoma. Further larger cohort studies are needed.