Surgical Options for Glaucoma Patients With Failed Glaucoma Drainage Devices: A Systematic Review.

PRCIS: This systematic review summarizes surgical options after failed glaucoma drainage devices, showing that second implants and cyclophotocoagulation provide meaningful intraocular pressure reduction, while trabeculectomy and newer surgical approaches may represent promising alternatives.

PURPOSE: Glaucoma drainage devices (GDDs) are essential in the management of refractory glaucoma, yet up to 10% fail annually. Optimal surgical management after GDD failure remains unclear. This systematic review summarizes current evidence on surgical options after failed GDDs.

METHODS

A systematic search of PubMed, Web of Science, and Scopus (November 26, 2025) was performed according to PRISMA guidelines. Eligible studies included observational designs and clinical trials reporting outcomes of surgical interventions in eyes with failed GDDs. Data on intraocular pressure (IOP), medications, success, and complications were extracted.

RESULTS

Forty-four studies (1560 eyes; 1518 patients) were included. Reported interventions included second GDD implantation (SGDD), cyclophotocoagulation (CPC), trabeculectomy, non-bleb-forming procedures (eg, trabectome, GATT), and revision surgeries. SGDD was the most common approach, lowering IOP by >30%, though success ranged from ∼30% at 3 years to >90% at 1 year, with frequent corneal decompensation. CPC achieved comparable IOP reductions (25%-45%) and fewer device-related complications, but a higher risk of chronic hypotony was occasionally reported. One randomized trial found similar efficacy between CPC and SGDD, with fewer reoperations in the CPC group. Revision and non-bleb-forming procedures yielded heterogeneous yet encouraging results. Pediatric outcomes were less favorable.

CONCLUSIONS

After GDD failure, several surgical options exist. SGDD remains the most studied for IOP reduction but possibly carries higher complication rates. CPC likely offers comparable efficacy with fewer reoperations, though chronic hypotony risk warrants caution. Trabeculectomy arises as a promising option in selected patients. Evidence remains limited by retrospective designs and variable success definitions.