Purpose of review: The Tube Versus Trabeculectomy (TVT) Study is a multicenter randomized clinical trial comparing the safety and efficacy of tube-shunt surgery to trabeculectomy with mitomycin C (MMC) in eyes with previous cataract and/or failed glaucoma surgery. This article interprets results from the TVT Study and applies them to clinical practice.
Recent findings: Both tube-shunt surgery and trabeculectomy with MMC produced intraocular pressure (IOP) reduction to the low teens throughout the 5-year duration of the study. Tube-shunt surgery was associated with use of more glaucoma medications than trabeculectomy with MMC during the first 2 years of the study, but medical therapy equalized with longer follow-up. Trabeculectomy with MMC had higher rates of surgical failure and reoperation for glaucoma compared with tube-shunt surgery. Vision loss occurred at a similar rate with the two surgical procedures. Early complications were more frequent after trabeculectomy with MMC relative to tube-shunt surgery, but both procedures had similar rates of late postoperative complications and serious complications.
Summary: Tube-shunt surgery and trabeculectomy with MMC are both viable surgical options for managing glaucoma in patients who have undergone prior cataract and/or failed filtering surgery. Results of the TVT Study support the expanding use of tube shunts beyond refractory glaucomas.