Effect of Alphagan on Retinal Blood Flow Autoregulation and Motion Detection in Patients With Normal Pressure Glaucoma

This study is ongoing, but not recruiting participants.
Sponsor:
Information provided by (Responsible Party):
Massachusetts Eye and Ear Infirmary
ClinicalTrials.gov Identifier:
NCT01105065
First received: April 14, 2010
Last updated: February 21, 2014
Last verified: February 2014
  Purpose

The investigators have completed a study in which the investigators examined the response of the retinal circulation to changes in posture from sitting to lying down in patients with Normal Tension Glaucoma (NTG). This alteration in position produces changes in the local blood pressure at the entrance to the retinal vasculature. In a healthy retina, the vasculature adapts by dilating and constricting in order to maintain a steady blood flow rate. In an eye with NTG, this often does not occur. Upon analysis at the completion of the study , the investigators found that the patients who had been taking Alphagan (brimonidine) during the study did not exhibit the blood flow increases typical of NTG while lying down; instead, they maintained a steady blood flow rate as did the group of healthy control subjects. The investigators primary objective is to now demonstrate in a prospective study that Alphagan can restore retinal vascular autoregulatory function in patients with NTG who do not autoregulate. The investigators will also determine the effect of Alphagan treatment on the patients' ability to detect motion.


Condition Intervention
Glaucoma
Drug: Alphagan (brimonidine) 0.15%

Study Type: Interventional
Study Design: Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Effect of Brimonidine 0.15% on Retinal Blood Flow Autoregulation and Motion Detection in Patients With Normal Tension Glaucoma

Resource links provided by NLM:


Further study details as provided by Massachusetts Eye and Ear Infirmary:

Primary Outcome Measures:
  • Presence or Absence of Retinal Blood Flow Autoregulation [ Time Frame: 8 weeks ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Improvement in Motion Detection [ Time Frame: 8 weeks ] [ Designated as safety issue: No ]

Estimated Enrollment: 40
Study Start Date: March 2010
Estimated Study Completion Date: December 2014
Estimated Primary Completion Date: December 2014 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Alphagan Drug: Alphagan (brimonidine) 0.15%
One drop in each eye three times a day for 8 weeks.
Other Name: Alphagan

  Eligibility

Ages Eligible for Study:   35 Years to 80 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Eligible subjects will have no history of IOP > 24 mm Hg in either eye.
  • All subjects will have open angles on gonioscopy with the filtering portion of the trabecular meshwork visible for 360° in both eyes.
  • Previously or newly diagnosed patient are required to have HVFs that are reliable and show loss consistent with nerve fiber layer atrophy.
  • Patients with glaucoma-like discs (CDR>0.7 in either eye) and normal/reliable visual fields who the PI has opted to observe without treatment will enter the study if they meet the other study criteria.
  • In order to facilitate the retinal blood flow measurements, only subjects with refractive error within the range -10 to +10 diopters, no lens opacities greater than 1+ cortical spokes or 2+ nuclear sclerosis, and pupillary dilation of at least 6 mm following mydriasis will be included.

Exclusion Criteria:

  • Patients with evidence of exfoliation or pigment dispersion syndrome in either eye.
  • Patients with a cup/disc ratio > 0.8.
  • Known history of allergy to brimonidine.
  • Patients already on treatment with brimonidine will be excluded from the study.
  • Diabetic retinopathy.
  • History of ocular laser or incisional surgery in either eye.
  • Use of systemic alpha-2 blockers.
  • Pregnant or planning to become pregnant.
  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT01105065

Locations
United States, Massachusetts
Massachusetts Eye and Ear Infirmary
Boston, Massachusetts, United States, 02114
Sponsors and Collaborators
Massachusetts Eye and Ear Infirmary
  More Information

No publications provided

Responsible Party: Massachusetts Eye and Ear Infirmary
ClinicalTrials.gov Identifier: NCT01105065     History of Changes
Other Study ID Numbers: 10-03-019 (75643)
Study First Received: April 14, 2010
Last Updated: February 21, 2014
Health Authority: United States: Institutional Review Board

Keywords provided by Massachusetts Eye and Ear Infirmary:
Normal Pressure Glaucoma

Additional relevant MeSH terms:
Glaucoma
Low Tension Glaucoma
Ocular Hypertension
Eye Diseases
Optic Nerve Diseases
Brimonidine
Adrenergic alpha-2 Receptor Agonists
Adrenergic alpha-Agonists
Adrenergic Agonists
Adrenergic Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Pharmacologic Actions
Physiological Effects of Drugs
Antihypertensive Agents
Cardiovascular Agents
Therapeutic Uses

ClinicalTrials.gov processed this record on July 20, 2014