Gonioscopy-Assisted Transluminal Trabeculotomy in Younger to Middle-Aged Adults: One-Year Outcomes

Abstract

To assess the 1-year surgical outcomes of gonioscopy-assisted transluminal trabeculotomy (GATT) in young to middle-aged patients. Retrospective case series. Eyes of patients between 18 and 64 years of age who underwent GATT, with and without concomitant cataract surgery, at 2 academic centers in Montreal, Canada. Success was defined as intraocular pressure (IOP) between 6 and 21 mmHg (criterion A) or between 6 and 18 mmHg (criterion B) and a relative IOP reduction of 20% or more compared with baseline. Failure consisted of not meeting the success criteria at 2 or more consecutive visits after the first postoperative month, reoperation because of uncontrolled IOP or disease progression, or loss of light perception. Predictors of success and postoperative changes in outcome measures, including IOP and medication use, were assessed. Intraoperative and postoperative adverse events were noted. Success, IOP, and medication reduction at the 1-year follow-up and baseline predictors of surgical success. Fifty-six eyes with a mean age of 46.94 ± 11.81 years and preoperative IOP of 27.70 ± 10.30 mmHg taking 3.73 ± 0.98 glaucoma medications were included. At 1 year, IOP decreased from 27.70 ± 10.30 mmHg before surgery to 14.04 ± 3.75 mmHg (49% reduction; P < 0.001) and medication use decreased from 3.73±0.98 medications before surgery to 1.82 ± 1.47 (51% reduction; P < 0.001). The 12-month success was 84% (according to both criteria), and younger age at diagnosis of glaucoma (18-39 years) was predictive of surgical success. The most common postoperative adverse events included transient hyphema, IOP spikes, and transient microcystic corneal edema. A paucity of evidence exists regarding the efficacy of GATT in young to middle-aged adults. Our results highlight that this surgical procedure has good 1-year outcomes with an acceptable safety profile, supported by the significant IOP and medication reduction observed after surgery. With younger age at diagnosis of glaucoma being a predictor of surgical success, the pathophysiologic features of open-angle glaucoma in younger patients may be more localized to the trabecular meshwork, therefore making GATT a particularly suitable procedure for these patients.