Tube Versus Trabeculectomy (TVT) Study

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00306852
Recruitment Status : Completed
First Posted : March 24, 2006
Results First Posted : November 25, 2015
Last Update Posted : November 25, 2015
Abbott Medical Optics
Information provided by (Responsible Party):
Steven J. Gedde, University of Miami

Brief Summary:
The purpose of the Tube Versus Trabeculectomy (TVT) Study is to compare the safety and efficacy of nonvalved tube shunt surgery to trabeculectomy with mitomycin C in patients with previous ocular surgery.

Condition or disease Intervention/treatment Phase
Glaucoma Procedure: Baerveldt implant Procedure: Trabeculectomy with mitomycin C Not Applicable

Detailed Description:

Glaucoma surgery is performed when further intraocular pressure (IOP) reduction is needed despite the use of maximum tolerated medical therapy and appropriate laser treatment. Trabeculectomy is generally used as the initial incisional surgical procedure in managing glaucoma. However, eyes in which trabeculectomy has failed are at greater risk of failure with subsequent filtering surgery. Wound modulation with antifibrotic agents, like mitomycin C (MMC) and 5-fluorouracil (5-FU), has been shown to increase the success rate of trabeculectomy in eyes that have undergone previous ocular surgery. Although antifibrotic agents have increased the likelihood of IOP control following filtering surgery, they have also increased the risk of complications. The prevalence of bleb leaks, bleb-related infections, and bleb dysesthesia associated with a perilimbal filtering bleb suggests the need to consider alternatives. Tube shunts (or glaucoma drainage implants) offer an alternative to trabeculectomy in the surgical management of glaucoma, and these devices have been growing in popularity in recent years.

Practice patterns vary in the surgical management of glaucoma in eyes with previous ocular surgery. In 1996, Chen and colleagues conducted an anonymous survey of members of the American Glaucoma Society (AGS) and Japanese Glaucoma Society (JGS) to evaluate use of antifibrotic agents and tube shunts. The survey presented ten clinical situations requiring glaucoma surgical intervention. The majority of respondents (59-83%) preferred trabeculectomy with MMC for the clinical scenarios involving prior ocular surgery, although many of those surveyed elected to use a tube shunt, trabeculectomy with 5-FU, or trabeculectomy without an antifibrotic agent. In 2002, Joshi and associates re-administered the same survey to members of the AGS. Respondents still favored trabeculectomy with MMC, but the percentage usage of tube shunts had significantly increased. The greatest practice pattern shift was observed in patients with previous cataract and glaucoma surgery. In particular, selection of tube shunts as the preferred surgical approach increased from 7% to 22% in eyes with prior trabeculectomy, and increased from 8% to 22% in eyes with prior extracapsular or intracapsular cataract extraction.

The lack of consensus among glaucoma surgeons regarding the use of tube shunts or trabeculectomy with an antifibrotic agent in eyes that have had prior cataract or glaucoma surgery likely relates to the fact that available clinical data has not shown one surgical procedure to be superior to the other. Similar surgical results have been reported with both glaucoma procedures in eyes with aphakia/pseudophakia and failed filters when studied separately. Success rates have ranged from 50% to 88% for tube shunts, and 48% to 86% for filtering surgery with an antifibrotic agent in case series studying aphakic/pseudophakic eyes. Success rates have ranged from 44% to 88% for tube shunts, and 61% to 100% for 5-FU and MMC trabeculectomy in eyes with failed filters. Comparable rates of severe complications have also been reported with tube shunt surgery and trabeculectomy with an adjunctive antifibrotic agent.

The Tube Versus Trabeculectomy (TVT) Study was designed to prospectively compare the safety and efficacy of nonvalved tube shunt surgery and trabeculectomy with MMC. Patients with uncontrolled glaucoma who had prior cataract extraction with intraocular lens implantation and/or failed filtering surgery were enrolled in this multicenter clinical trial and randomized to placement of a 350 Baerveldt glaucoma implant (Advanced Medical Optics, Irvine, CA) or trabeculectomy with MMC (0.4 mg/ml for 4 minutes). The goal of this investigator initiated trial is to provide information that will assist in surgical decision-making in similar patient groups.

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 212 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Tube Versus Trabeculectomy (TVT) Study
Study Start Date : October 1999
Actual Primary Completion Date : April 2009
Actual Study Completion Date : May 2009

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Glaucoma
Drug Information available for: Mitomycin
U.S. FDA Resources

Arm Intervention/treatment
Active Comparator: Trabeculectomy
Trabeculectomy with mitomycin C
Procedure: Trabeculectomy with mitomycin C
Patients will be randomized to receive either a Trabeculectomy (guarded filtration surgery) with mitomycin C (0.4 mg/ml for 4 minutes) or a 350 mm^2 Baerveldt glaucoma implant
Active Comparator: Implant
Baerveldt Implant
Procedure: Baerveldt implant
Patients will be randomized to receive a 350 mm^2 Baerveldt glaucoma implant or a Trabeculectomy (guarded filtration surgery) with mitomycin C (0.4 mg/ml for 4 minutes)

Primary Outcome Measures :
  1. Change in Intraocular Pressure [ Time Frame: Baseline to 5 years ]
    The data value from the Baseline visit and 5 year follow-up visit were combined. Specifically, values were calculated by subtracting the 5 Year Intraocular Pressure from the Baseline Intraocular Pressure.

  2. Rate of Complications [ Time Frame: 5 years ]
    Complications associated with both surgical procedures

Secondary Outcome Measures :
  1. Visual Acuity [ Time Frame: 5 years ]
    Visual acuity was measured by the total number of letters read (correctly) using a ETDRS eye chart

  2. Reoperations for Glaucoma [ Time Frame: 5 years ]
    Reoperations for glaucoma was defined as additional glaucoma surgery requiring a return to the operating room.

  3. Need for Supplemental Medical Therapy [ Time Frame: 5 years ]
    The number of supplemental glaucoma medications required in the Implant Group and Trabeculectomy Group at 5 years

  4. Failure Rate [ Time Frame: 5 years ]
    Failure was prospectively defined as IOP greater than 21 mm Hg or less than 20 percent reduction below baseline on 2 consecutive follow-up visits after 3 months, IOP less than or equal to 5 mm Hg on 2 consecutive follow-up visits after 3 months, re-operation for glaucoma, or loss of light perception vision.

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 85 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Age 18 to 85 years
  • Intraocular pressure greater than or equal to 18 mm Hg and less than or equal to 40 mm Hg
  • Previous trabeculectomy, cataract extraction with intraocular lens implantation, or both

Exclusion Criteria:

  • Unwilling or unable to give consent, unwilling to accept randomization, or unable to return for scheduled protocol visits
  • Pregnant or nursing women
  • No light perception vision
  • Active iris neovascularization or active proliferative retinopathy
  • Iridocorneal endothelial syndrome
  • Epithelial or fibrous downgrowth
  • Aphakia
  • Vitreous in the anterior chamber for which a vitrectomy is anticipated
  • Chronic or recurrent uveitis
  • Severe posterior blepharitis
  • Unwilling to discontinue contact lens use after surgery
  • Previous cyclodestructive procedure, scleral buckling procedure, or presence of silicone oil
  • Conjunctival scarring precluding a trabeculectomy superiorly
  • Need for glaucoma surgery combined with other ocular procedures (eg cataract surgery, penetrating keratoplasty, or retinal surgery) or anticipated need for additional ocular surgery

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00306852

United States, California
Scripps Clinic
La Jolla, California, United States, 92036
University of Southern California
Los Angeles, California, United States, 90033
University of California Davis
Sacramento, California, United States, 95817
United States, Florida
University of Florida
Gainesville, Florida, United States, 32610
Bascom Palmer Eye Institute
Miami, Florida, United States, 33136
United States, Illinois
Loyola University
Maywood, Illinois, United States, 60153
United States, Indiana
Indiana University
Indianapolis, Indiana, United States, 46202
United States, Missouri
St. Louis University
St. Louis, Missouri, United States, 63104
United States, New York
New York Eye and Ear Infirmary
New York, New York, United States, 10003
United States, North Carolina
Duke University
Durham, North Carolina, United States, 27710
United States, Oklahoma
University of Oklahoma
Oklahoma City, Oklahoma, United States, 73104
United States, South Carolina
Medical University of South Carolina
Charleston, South Carolina, United States, 29425
United States, Texas
University of Texas Houston
Houston, Texas, United States, 77030
United States, Virginia
University of Virginia
Charlottesville, Virginia, United States, 22908
United States, Wisconsin
University of Wisconsin
Madison, Wisconsin, United States, 53705
Medical College of Wisconsin
Milwaukee, Wisconsin, United States, 53226
United Kingdom
Moorfields Eye Hospital
London, United Kingdom
Sponsors and Collaborators
University of Miami
Abbott Medical Optics
Study Chair: Steven J Gedde, M.D. Bascom Palmer Eye Institute
Study Chair: Dale K Heuer, M.D. Medical College of Wisconsin
Study Chair: Richard K Parrish, M.D. Bascom Palmer Eye Institute

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Steven J. Gedde, Professor of Ophthalmology, University of Miami Identifier: NCT00306852     History of Changes
Other Study ID Numbers: 19990167
First Posted: March 24, 2006    Key Record Dates
Results First Posted: November 25, 2015
Last Update Posted: November 25, 2015
Last Verified: October 2015

Keywords provided by Steven J. Gedde, University of Miami:
Tube shunt surgery

Additional relevant MeSH terms:
Ocular Hypertension
Eye Diseases
Antibiotics, Antineoplastic
Antineoplastic Agents
Alkylating Agents
Molecular Mechanisms of Pharmacological Action
Nucleic Acid Synthesis Inhibitors
Enzyme Inhibitors