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Retinal Vascular Reactivity in Subjects With Newly Diagnosed Glaucoma Before and After Selective Laser Trabeculoplasty

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified September 2010 by University of Toronto.
Recruitment status was:  Recruiting
University of Western Ontario, Canada
Information provided by:
University of Toronto Identifier:
First received: June 29, 2010
Last updated: September 27, 2010
Last verified: September 2010
The purpose of this study is to assess retinal blood flow and vascular reactivity in patients with newly diagnosed primary open angle glaucoma pre- and post-primary Selective Laser Trabeculoplasty(SLT). Canon Laser Blood Flowmeter will be used for the assessment of retinal blood flow.

Condition Intervention
Glaucoma Procedure: Selective Laser Trabeculoplasty

Study Type: Observational
Study Design: Observational Model: Case-Only
Time Perspective: Prospective
Official Title: Retinal Vascular Reactivity in Response to Isoxic Hypercapnia in Subjects With Newly Diagnosed Glaucoma

Resource links provided by NLM:

Further study details as provided by University of Toronto:

Primary Outcome Measures:
  • blood flow [ Time Frame: before and two-week after SLT ]
    The Canon Laser Blood Flowmetry will be used to assess the retinal blood flow.

Secondary Outcome Measures:
  • Intraocuclar pressure [ Time Frame: before and two-week after SLT ]
    Intraocular pressure (IOP) will be measured by Goldmann applanation tonometry.

Estimated Enrollment: 12
Study Start Date: November 2008
Estimated Primary Completion Date: November 2011 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
untreated glaucoma patients
We will evaluate the blood flow before and after Selective Laser Trabeculoplasty in patients with primary open angel glaucoma.
Procedure: Selective Laser Trabeculoplasty
Patient will have selective laser trabeculoplasty as the first treatment for glaucoma. This treatment will be dictated clinically, since we do not assign the interventions.

Detailed Description:
We previously found that vascular reactivity improved after short term treatment with dorzolamide drops. It is not clear whether this improvement was a direct effect of the medication or secondary effect of the decrease in IOP. We would like to see the change of vascular reactivity before and after SLT, which will decrease the intraocular pressure without pharmacologic effect.

Ages Eligible for Study:   40 Years to 75 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
patient with untreated primary open angle glaucoma

Inclusion Criteria:

  1. Age 40-75 years (Male or Female)
  2. Best corrected visual acuity of at least 20/40
  3. No previous treatment for glaucoma
  4. Ametropia less than ±6.0 DS and ±2.5 DC)
  5. Non-smoker
  6. No cardiovascular/respiratory disorders

Exclusion Criteria:

  1. Past history of diabetes and cerebrovascular accident
  2. Vascular occlusive disease affecting the ocular circulation such as: diabetic retinopathy, retinal vein occlusion and retinal artery occlusion
  3. Previous intraocular surgery
  4. Ocular media opacities limiting the use of the imaging tests
  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 identifier: NCT01209975

Contact: Tien Wong 416-603-5694

Canada, Ontario
Toronto Western Hospital Recruiting
Toronto, Ontario, Canada, M5T2S8
Contact: Tien Wong    416-603-5694   
Sponsors and Collaborators
University of Toronto
University of Western Ontario, Canada
Principal Investigator: Chris Hudson, PhD University of Toronto
  More Information

Responsible Party: Dr. Chris Hudson, Department of Ophthalmology and Vision Science Identifier: NCT01209975     History of Changes
Other Study ID Numbers: SLT-blood flow study
Study First Received: June 29, 2010
Last Updated: September 27, 2010

Keywords provided by University of Toronto:
blood flow

Additional relevant MeSH terms:
Ocular Hypertension
Eye Diseases processed this record on August 17, 2017