Effect of Preoperative Antiglaucoma Medication Duration on Surgical Outcomes of Gonioscopy-Assisted Transluminal Trabeculotomy in Open-Angle Glaucoma

Abstract

Purpose: To evaluate the impact of preoperative antiglaucoma medication duration on the surgical outcomes of gonioscopy-assisted transluminal trabeculotomy (GATT) in patients with open-angle glaucoma (OAG). Design: Retrospective comparative study. Patients and Methods: This retrospective case series included 64 eyes from patients diagnosed with primary OAG or pseudoexfoliative glaucoma who underwent 360-degree GATT. Patients were categorized into three groups based on the duration of preoperative medication use: short-term (< 2 years), moderate-term (2–5 years), and long-term (> 5 years). Intraocular pressure (IOP) was measured using Goldmann applanation tonometry during follow-up visits, and surgical success was defined based on IOP reduction criteria. The number of glaucoma medications, best-corrected visual acuity, and postoperative complications were also recorded. Kaplan–Meier survival analysis was used to assess success rates. Results: The mean follow-up duration was 17.2 ± 6.8 months. The short-term, moderate-term, and long-term groups achieved significant IOP reductions (p < 0.001), with final mean IOPs of 13.2 ± 4.7 mmHg, 17.7 ± 6.4 mmHg, and 18.1 ± 6.9 mmHg, respectively (p = 0.002). The mean number of postoperative medications decreased significantly across all groups (p = 0.032). Qualified success rates were 92.3%, 77.2%, and 79.3% for the short-term, moderate-term, and long-term groups, respectively, while complete success rates were 76.9%, 63.6%, and 58.6%. Conclusion: GATT effectively lowers IOP in patients with OAG, though prolonged preoperative medication use is associated with reduced surgical success and higher postoperative medication dependence. Early surgical intervention may enhance long-term outcomes for patients with a history of escalating medication regimens.