Factors associated with achieving intraocular pressure lower than 15 mmHg by Trabectome surgery in primary open-angle glaucoma

To assess good prognostic factors of Trabectome surgery in primary open-angle glaucoma (POAG), clinical records of patients with POAG who underwent Trabectome surgery with/without cataract surgery as the first additive therapy to eye drops between January 2015 and March 2018 were retrospectively reviewed. Overall, data of 79 eyes (79 patients; 50 men; mean age, 68.0 years) up to postoperative 24 months were analyzed. Their mean intraocular pressure (IOP) was 20.4 ± 6.0 mmHg at baseline. Forty-two eyes (53.2%) achieved an IOP < 15 mmHg and ≥ 20% reduction from baseline without additional treatments. Phakic eyes had a better survival probability than pseudophakic eyes after adjusting for age, sex, baseline IOP, best-corrected visual acuity, and eye drop score (hazard ratio 3.096; 95% confidence interval [95% CI] 1.367–7.013; P = 0.007). Phakic eyes treated with combined Trabectome and cataract surgeries (mean survival time, 22.250 months; 95% CI 17.606–26.894) had a better survival probability than pseudophakic eyes treated with Trabectome surgery only (mean survival time, 12.111 months; 95% CI 8.716–15.506; P = 0.009) after the adjustment. Among the eyes treated with Trabectome surgery only, phakic eyes required significantly less additional treatments than pseudophakic eyes (P = 0.04). Trabectome surgery may be indicated for phakic eyes with POAG in addition to eye-drop therapy.

Long-Term Clinical Results of Trabectome Surgery

Purpose: To analyze the long-term results of trabectome surgery and to characterize risk factors for failure.Method: This is a single-center retrospective study including 66 eyes of 56 patients who underwent trabectome alone (TA) or phacotrabectome (TP) surgeries between 2012-2016. Surgical success was defined as intraocular pressure (IOP) drop by 20% or IOP ≤21 mmHg and no further glaucoma surgery. Risk factors for further surgeries were analyzed with Cox proportional hazard ratio models. Cumulative success analysis of subgroups was completed with the Kaplan Meier analysis.Results: Mean follow-up period was 59.7±14.1 months. During the follow-up period, 15 of 62 (24.2%) eyes had additional glaucoma surgery. The mean preoperative IOP was 26.8±6.5 mmHg. The mean last visit IOP was 18.7±4.5 mmHg (p<0.01). IOP decreased 30.1% from baseline at the last visit. Average numbers of medications used were 3.42 ±0.76 (range 1-4) and 2.45±1.33 (range 0-4) at preoperative and last visit, respectively (p<0.01). The risk factors for further surgery requirements were higher baseline IOP (HR:1.12, p:0.01), higher central corneal thickness (CCT) (HR:1.01, p:0.04), and higher amounts of preoperative drugs (HR:2.22, p:0.08). The cumulative probability of success was 93.5%, 90.5%, 85.5%, 80.6%, and 77.4% at 3, 12, 24, 36, and 60 months, respectively. Kaplan Meier survival plots indicating the time of additional glaucoma surgery in the subgroups showed higher survival probability in primary open angle glaucoma (POAG), males, phacotrabectome cases, early stage glaucoma, and eyes without previous glaucoma surgery. Conclusion: Trabectome success ratio was 50% at 59 months. Higher baseline IOP and thicker CCT are associated with an increased risk of further glaucoma surgery.

Ab-Interno Trabeculotomy

The Trabectome (NeoMedix Corporation, San Juan Capistrano, CA, USA) is a US Food and Drug Administration—approved surgical device which removes a segment of the trabecular meshwork and the inner wall of the Schlemm’s canal using an ab-interno approach, enhancing aqueous outflow via increased access to the Schlemm’s canal and the collector channels. This is a bleb-less procedure which spares the conjunctiva, hence does not adversely affect the outcome of subsequent conventional glaucoma filtration surgeries. Multiple studies have shown that Trabectome surgery results in a reduction in IOP and the number of ocular hypotensive agents, though the efficacy is modest compared with conventional filtration surgery. The safety profile of Trabectome surgery is favorable compared with conventional glaucoma surgery, with the most common complication being intraoperative and postoperative bleeding. Additional research is required to understand how the efficacy of Trabectome surgery can be maximized.