Three-Year Follow-up of the Tube Versus Trabeculectomy Study

Purpose

To report 3-year results of the Tube Versus Trabeculectomy (TVT) Study.

Design

Multicenter randomized clinical trial.

Methods

setting: Seventeen clinical centers. study population: Patients 18 to 85 years of age who had previous trabeculectomy, cataract extraction with intraocular lens implantation, or both and uncontrolled glaucoma with intraocular pressure (IOP) ≥18 mm Hg and ≤40 mm Hg on maximum tolerated medical therapy. interventions: A 350-mm² Baerveldt glaucoma implant or trabeculectomy with mitomycin C (MMC 0.4 mg/ml for 4 minutes). main outcome measures: IOP, visual acuity, use of supplemental medical therapy, surgical complications, and failure (IOP >21 mm Hg or not reduced by 20%, IOP ≤5 mm Hg, reoperation for glaucoma, or loss of light perception vision).

Results

A total of 212 eyes of 212 patients were enrolled, including 107 in the tube group and 105 in the trabeculectomy group. At 3 years, IOP (mean ± standard deviation [SD]) was 13.0 ± 4.9 mm Hg in the tube group and 13.3 ± 6.8 mm Hg in the trabeculectomy group (P = .78). The number of glaucoma medications (mean ± SD) was 1.3 ± 1.3 in the tube group and 1.0 ± 1.5 in the trabeculectomy group (P = .30). The cumulative probability of failure during the first 3 years of follow-up was 15.1% in the tube group and 30.7% in the trabeculectomy group (P = .010; hazards ratio, 2.2; 95% confidence interval, 1.2 to 4.1). Postoperative complications developed in 42 patients (39%) in the tube group and 63 patients (60%) in the trabeculectomy group (P = .004). Surgical complications were associated with reoperation and/or loss of ≥2 Snellen lines in 24 patients (22%) in the tube group and 28 patients (27%) in the trabeculectomy group (P = .58).

Conclusions

Tube shunt surgery had a higher success rate compared to trabeculectomy with MMC during the first 3 years of follow-up in the TVT Study. Both procedures were associated with similar IOP reduction and use of supplemental medical therapy at 3 years. While the incidence of postoperative complications was higher following trabeculectomy with MMC relative to tube shunt surgery, most complications were transient and self-limited.