Outcomes of Glaucoma Reoperations in the Tube Versus Trabeculectomy (TVT) Study

Abstract

Purpose To describe the incidence and outcomes of reoperations for glaucoma in the Tube Versus Trabeculectomy (TVT) Study. Design Cohort study of patients in a multicenter randomized clinical trial. Methods The TVT Study enrolled 212 patients with medically uncontrolled glaucoma who had previous cataract and/or glaucoma surgery. Randomization assigned 107 patients to surgery with a tube shunt (350-mm2 Baerveldt glaucoma implant) and 105 patients to trabeculectomy with mitomycin C (0.4 mg/ml for 4 minutes). Data were analyzed from patients who failed their assigned treatment and had additional glaucoma surgery. Outcome measures included intraocular pressure (IOP), use of glaucoma medications, visual acuity, surgical complications, and failure (IOP > 21 mm Hg or not reduced by 20%, IOP ≤ 5 mm Hg, additional glaucoma surgery, or loss of light perception vision). Results Additional glaucoma surgery was performed in 8 patients in the tube group and 18 patients in the trabeculectomy group in the TVT Study, and the 5-year cumulative reoperation rate was 9% in the tube group and 29% in the trabeculectomy group (p = .025). Follow-up (mean ± SD) after additional glaucoma surgery was 28.0 ± 16.0 months in tube group and 30.5 ± 20.4 months in the trabeculectomy group (p = .76). At 2 years after a glaucoma reoperation, IOP (mean ± SD) was 15.0 ± 5.5 mm Hg in the tube group and 14.4 ± 6.6 mm Hg in the trabeculectomy group (p = .84). The number of glaucoma medications (mean ± SD) after 2 years of follow-up was 1.1 ± 1.3 in the tube group and 1.4 ± 1.4 in the trabeculectomy group (p = .71). The cumulative probability of failure at 1, 2, 3, and 4 years after additional glaucoma surgery was 0%, 43%, 43%, and 43% respectively in the tube group, and 0%, 9%, 20%, and 47% in the trabeculectomy group (p = .28). Reoperations to manage complications were required in 1 (13%) patient in the tube group and 5 (28%) patients in the trabeculectomy group (p = .63). Conclusions The rate of reoperation for glaucoma was higher following trabeculectomy with mitomycin C than tube shunt surgery in the TVT Study. Similar surgical outcomes were observed after additional glaucoma surgery, irrespective of initial randomized treatment in the study.

New findings in the diagnosis and treatment of primary angle-closure glaucoma

“…Glaucoma drainage implants are generally considered in eyes with complicated PACG when trabeculectomy failed in controlling IOP (Gedde et al, 2012b;Saheb et al, 2014).…”

One Year of Glaucoma Research in Review—2013 to 2014

“…The new data reveal the rate of subsequent glaucoma surgery was higher following trabeculectomy (29%) than tube shunt (9%, P = 0.025). 59 IOP, number of glaucoma medications, and cumulative probability of failure following additional glaucoma surgery were not significantly different between the groups. 59 …”

“…59 IOP, number of glaucoma medications, and cumulative probability of failure following additional glaucoma surgery were not significantly different between the groups. 59 …”

Grooved Glaucoma Drainage Devices That Continuously Deliver Cyclosporine A Decrease Postsurgical Scar Formation in Rabbit Eyes

“…9,26,27 These benefits are related to the large GDD body, less disturbance of the anterior chamber, and greater distance from the anterior conjunctiva where scar formation is more active because Tenon's membrane is thicker in this region. However, GDD implantation is sometimes associated with complications, such as hypotony with suprachoroidal hemorrhage and shallowing of the anterior chamber, tube obstruction by fibrin clot, and long-term failure caused by bleb fibrosis.…”