Postoperative Complications in the Primary Tube Versus Trabeculectomy Study During 5 Years of Follow-up

Abstract

Purpose: To describe postoperative complications encountered in the Primary Tube Versus Trabeculectomy (PTVT) Study during 5 years of follow-up.

Design: Multicenter randomized clinical trial.

Participants: A total of 242 eyes of 242 patients with medically uncontrolled glaucoma and no previous incisional ocular surgery, including 125 patients in the tube group and 117 patients in the trabeculectomy group.

Methods: Patients were enrolled at 16 clinical centers and randomly assigned to treatment with a tube shunt (350-mm² Baerveldt glaucoma implant) or trabeculectomy with mitomycin C (MMC, 0.4 mg/ml for 2 minutes).

Main outcome measures: Surgical complications, reoperations for complications, visual acuity, and cataract progression.

Results: Early postoperative complications occurred in 24 patients (19%) in the tube group and 40 patients (34%) in the trabeculectomy group (P = 0.013). Late postoperative complications developed in 27 patients (22%) in the tube group and 32 patients (27%) in the trabeculectomy group (P = 0.37). Serious complications producing vision loss and/or requiring a reoperation were observed in 3 patients (2%) in the tube group and 9 patients (8%) in the trabeculectomy group (P = 0.11). Cataract progression was seen in 65 patients (52%) in the tube group and 52 patients (44%) in the trabeculectomy group (P = 0.30). Surgical complications were not associated with a higher rate of treatment failure (P = 0.61), vision loss (P = 1.00), or cataract progression (P = 0.77) CONCLUSIONS: A large number of surgical complications were observed in the PTVT Study, but most were transient and self-limited. The incidence of early postoperative complications was higher following trabeculectomy with MMC than with tube shunt surgery. The rates of late postoperative complications, serious complications, and cataract progression were similar with both surgical procedures after 5 years of follow-up. Surgical complications did not increase the risk of treatment failure, vision loss, or cataract progression.

Keywords: Glaucoma surgery; Randomized clinical trial; Surgical complications; Trabeculectomy; Tube shunt.