Outcomes of Second Trabeculectomy Versus Glaucoma Drainage Device in Juvenile Open-angle Glaucoma After Primary Trabeculectomy Failure.

Precis: Second trabeculectomy and glaucoma drainage device implantation offer similar success rates for juvenile open angle glaucoma after initial trabeculectomy failure. However, second trabeculectomies required fewer medications. A quarter of patients in both groups required a third operation after 2.5±2.3 years.

Purpose: To compare outcomes between second trabeculectomy surgery versus glaucoma drainage device (GDD) insertion in juvenile open-angle glaucoma (JOAG) patients after primary trabeculectomy failure.

Method: A retrospective review was performed on all JOAG patients who underwent a second glaucoma surgery after primary trabeculectomy failure across two tertiary hospitals in Bangkok, Thailand between 2009 and 2020. Demographics, intraoperative reports, and clinical findings were collected. The primary outcomes were complete and qualified success rates at 5 years; secondary outcomes included differences in intraocular pressures and number of glaucoma medications post-operatively.

Results: Fifty-two eyes of 38 patients underwent a second glaucoma surgery after primary trabeculectomy: 30 had a second trabeculectomy, 17 received a GDD (10 valved, 7 non-valved), and 5 underwent cyclophotocoagulation. Prior to surgery, there were no significant differences except in mean refractive error. Average follow-up length was 66.9±53.7 months. Qualified success rates were 81.5% and 63.2% at 3 and 5 years (complete success: 55.6% and 42.1%) for the second trabeculectomy group and 80.0% and 70.0% (complete success: 53.3% and 50.0%) for the GDD group, respectively. There were no significant differences in group success or IOP post-operatively. The GDD group required more medications at 5 years (1.3±1.9 vs. 2.3±1.5, P=0.03). Two cases of tube exposure in the GDD group resulted in implant removal. About a quarter of patients in both groups required a third operation after 2.5±2.3 years.

Conclusion: Both second trabeculectomy and GDD insertion are effective treatments for JOAG after trabeculectomy failure. Second trabeculectomy required fewer medications for IOP control.