Two-year clinical outcomes of standalone gonioscopy-assisted transluminal trabeculotomy in normal-tension glaucoma

Purpose To evaluate the 2-year efficacy and safety of gonioscopy-assisted transluminal trabeculotomy (GATT) for normal-tension glaucoma (NTG). Methods This single-center retrospective case series included 9 NTG patients (12 eyes) undergoing GATT, with follow-up at postoperative day 1, week 1, and months 1, 3, 6, 12, 18, and 24. Primary outcomes were changes in intraocular pressure (IOP) and IOP-lowering medication burden at 24 months (counted by active ingredients). Complete and qualified success were assessed using strict criteria (from postoperative month 1 onward: IOP 6–15 mmHg and ≥20% reduction from baseline). Postoperative events and additional interventions/reoperations were recorded. Paired t tests or Wilcoxon signed-rank tests were used as appropriate; a one-eye-per-patient sensitivity analysis was performed. Results The median age at surgery was 65 (53–70) years, and most eyes had moderate-to-advanced glaucoma. Mean IOP decreased from 17.33 ± 3.53 mmHg to 13.33 ± 2.35 mmHg at 24 months (mean reduction 4.00 ± 2.86 mmHg; 95% CI 2.18–5.82; t = 4.844; p 0.001), corresponding to a 23.1% reduction. Medication burden decreased from 1 (0, 2) to 0 (0, 0) ( Z = −2.251; p = 0.024). At 24 months, qualified and complete success rates were both 50.0% (6/12); sensitivity analysis ( n = 9) was consistent. No hypotony, IOP spikes, or serious complications occurred. Events were mild and self-limited (mainly hyphema and aqueous flare). No SLT, needling, or additional glaucoma surgery was required. Conclusion GATT significantly reduced IOP and medication burden in NTG with a safety profile through 24 months. Larger prospective studies are warranted.