Earlier Intraocular Pressure Control After Ahmed Glaucoma Valve Implantation for Glaucoma

The recruitment status of this study is unknown because the information has not been verified recently.
Verified June 2012 by University of California, Los Angeles.
Recruitment status was  Recruiting
Sponsor:
Information provided by (Responsible Party):
Simon Law, University of California, Los Angeles
ClinicalTrials.gov Identifier:
NCT00869141
First received: March 24, 2009
Last updated: June 12, 2012
Last verified: June 2012
  Purpose

The purpose of this study is to compare the occurrence rate of the high pressure phase and the final pressure outcomes between patients treated with glaucoma medication prior to the expected onset of the high pressure phase to those patients who have glaucoma medication started at the onset of the high pressure phase. The investigators hypothesize that if glaucoma medications are started prior to the expected onset of high pressure phase, the high pressure phase will not occur as frequently and the ultimate pressure level will be lower than if the glaucoma medications are started at the onset of this phase.


Condition Intervention Phase
Glaucoma
Drug: glaucoma medications (Timolol, Brimonidine, Dorzolamide, Brinzolamide)
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Earlier Intraocular Pressure Control After Ahmed Glaucoma Valve Implantation for Glaucoma

Resource links provided by NLM:


Further study details as provided by University of California, Los Angeles:

Primary Outcome Measures:
  • Intraocular pressure after Ahmed valve implantation for glaucoma [ Time Frame: within 3 months after surgery ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • rate of hypertensive phase after Ahmed valve implantation for glaucoma [ Time Frame: within 3 months after surgery ] [ Designated as safety issue: No ]

Estimated Enrollment: 55
Study Start Date: March 2009
Estimated Study Completion Date: March 2013
Estimated Primary Completion Date: March 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Research arm
Receive glaucoma medications if the eye pressure more than 10 mmHg after AHmed valve implantation
Drug: glaucoma medications (Timolol, Brimonidine, Dorzolamide, Brinzolamide)
Subjects may receive glaucoma medications after Ahmed valve implantation
Other Name: Timolol, Brimonidine, Dorzolamide, Brinzolamide
Active Comparator: Standard of care arm
Receive glaucoma medication if eye pressure more than 17 mmHg after Ahmed valve implantation
Drug: glaucoma medications (Timolol, Brimonidine, Dorzolamide, Brinzolamide)
Subjects may receive glaucoma medications after Ahmed valve implantation
Other Name: Timolol, Brimonidine, Dorzolamide, Brinzolamide

Detailed Description:

Tube shunt procedures are a popular surgery for the control of glaucoma. Tube shunt devices are designed to drain eye fluid (aqueous humor) through a tube inserted into the front chamber of the eye (anterior chamber) to a plate secured to the mid-posterior section of the outer eyeball wall. The body then lays down collagen tissue and forms a capsule around the plate. The fluid filters through the capsule of collagen tissue and is reabsorbed into the ocular and systemic circulation. The collagen tissue continues to remodel itself over a long period of time (up to years). However, a well characterized, yet poorly understood, phenomenon occurs in many patients in the 4-8 weeks after the device's implantation, called the hypertensive phase. The pressure of the eye can increase from a desirable level of about 10 immediately after the tube shunt implantation to much higher levels, in the range of 20 to 30's, and then it may gradually return to less than 20. Such a high pressure phase can cause irreversible damage an eye with glaucoma. The usual management of a high pressure phase is to start glaucoma medications as soon as it is detected. A previous study we conducted showed that this high pressure phase resolves in about half of patients with medical therapy, but the other half may continue to have higher than expected pressures. The exact cause of this high pressure phase is unknown. However, it is postulated that the mechanism may involve a compaction collagen tissue layers under the eye's own fluid pressure while the collagen tissue is being laid down, which in turn creates a firm, dense capsule that makes escape of fluid difficult. Therefore, it is argued that if the formation of eye fluid is reduced by medication during this initial period when the collagen tissue is laid down, the compaction of collagen, and subsequently the high pressure phase may be avoided.

The purpose of this study is to compare the occurrence rate of the high pressure phase and the final pressure outcomes between patients treated with glaucoma medication prior to the expected onset of the high pressure phase to those patients who have glaucoma medication started at the onset of the high pressure phase. We hypothesize that if glaucoma medications are started prior to the expected onset of high pressure phase, the high pressure phase will not occur as frequently and the ultimate pressure level will be lower than if the glaucoma medications are started at the onset of this phase.

We believe that this study will have a very significant impact on the management of glaucoma with tube shut procedures. If it is true that the rate and pressure level of the hypertensive phase can be reduced by simply starting glaucoma medications to reduce the formation of eye fluid before the expected the high pressure phase begins, which is generally 4 weeks after implantation of the tube shunt device, glaucoma patients can be saved from exposure to the very high level of eye pressure, and the eventual pressure control may be better.

  Eligibility

Ages Eligible for Study:   18 Years to 85 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  1. Patients requiring Ahmed glaucoma valve implantation to control intraocular pressure between the ages of 18 and 85 years.

Exclusion Criteria:

  1. Unwilling or unable to give consent or unwilling to accept randomization.
  2. Patient out of area and potentially unavailable for follow-up visits.
  3. Known allergic reaction to timolol, brimonidine, dorzolamide, brinzolamide, or sulfa drugs.
  4. Known medical contraindications to the use of beta-blockers, including congestive heart failure, heart block, asthma, and chronic obstructive pulmonary disease.
  5. Concurrent intraocular procedure with Ahmed glaucoma valve implantation
  6. Previous Ahmed glaucoma valve implantation
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00869141

Contacts
Contact: Simon K Law, MD (310)794-1477 law@jsei.ucla.edu
Contact: JoAnn Giaconi, MD (310)825-0146 giaconi@jsei.ucla.edu

Locations
United States, California
Juels Stein Eye Institute Recruiting
Los Angeles, California, United States, 90095
Contact: Simon K Law, MD    310-794-1477    law@jsei.ucla.edu   
Contact: JoAnn Giaconi, MD    (310)825-0146    giaconi@jsei.ucla.edu   
Principal Investigator: Simon K Law, MD         
Sponsors and Collaborators
University of California, Los Angeles
Investigators
Principal Investigator: Simon K Law, MD Jules Stein Eye Institute, University of California Los Angeles
  More Information

Additional Information:
No publications provided

Responsible Party: Simon Law, Clinical Associate Professor of Health Sciences, University of California, Los Angeles
ClinicalTrials.gov Identifier: NCT00869141     History of Changes
Other Study ID Numbers: UCLA IRB#08-10-110-01
Study First Received: March 24, 2009
Last Updated: June 12, 2012
Health Authority: United States: Institutional Review Board

Keywords provided by University of California, Los Angeles:
Glaucoma tube shunt procedure

Additional relevant MeSH terms:
Glaucoma
Eye Diseases
Ocular Hypertension
Brimonidine
Brinzolamide
Dorzolamide
Timolol
Adrenergic Agents
Adrenergic Agonists
Adrenergic alpha-2 Receptor Agonists
Adrenergic alpha-Agonists
Adrenergic Antagonists
Adrenergic beta-Antagonists
Anti-Arrhythmia Agents
Antihypertensive Agents
Carbonic Anhydrase Inhibitors
Cardiovascular Agents
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Neurotransmitter Agents
Pharmacologic Actions
Physiological Effects of Drugs
Therapeutic Uses

ClinicalTrials.gov processed this record on October 22, 2014