Three-year follow-up of the tube versus trabeculectomy study

Abstract

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

Design: Multicenter randomized clinical trial.

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) > or =18 mm Hg and < or =40 mm Hg on maximum tolerated medical therapy.

Interventions: A 350-mm(2) 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 < or =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 > or =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.

Trial registration: ClinicalTrials.gov NCT00306852.