Measurement of the Eye's Blood Vessels Using the Dynamic Vessel Analyzer (DVA)

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: NCT00783029
Recruitment Status : Completed
First Posted : October 31, 2008
Last Update Posted : February 7, 2012
Information provided by (Responsible Party):
Kerstin Bettermann, Penn State University

Brief Summary:
The purpose of this research study is examine the response of the blood vessels in the eye to a light flicker stimulus using the Dynamic Vessel Analyzer (DVA) on two separate days in healthy individuals. The DVA uses an instrument which is used during routine eye examinations. The hypothesis of the study is that the changes in eye's blood vessel will be similar between the two visits; thus establishing reproducibility of the measurements for future comparisons to individuals with stroke or heart disease. In addition, this study will compare the eye's blood vessel responses to responses of the blood vessels in the arm using Doppler ultrasound.

Condition or disease

Detailed Description:
Retinal blood vessels have been suggested to be an index of the cerebral and coronary microvasculature function. Since the retinal vessels are not under direct sympathetic control, this vascular bed is an ideal location to examine local mechanisms of vascular regulation(i.e. metabolite/endothelial and myogenic). Based on previously published data on animal and human responses, the central purpose for the proposed research is to compare the retinal and brachial vasodilatation responses in healthy subjects using the Dynamic Vessel Analyzer (DVA). Our rationale for this proposal is to better understand retinal blood flow in healthy individuals, gain insight into vascular reactivity in different vascular beds, and lastly to establish standards and reproducibility of DVA Measurements.

Study Type : Observational
Actual Enrollment : 87 participants
Observational Model: Case-Only
Time Perspective: Prospective
Official Title: Reproducibility of Dynamic Vessel Analyzer Measurements and Establishment of Standards
Study Start Date : October 2008
Actual Primary Completion Date : December 2011
Actual Study Completion Date : December 2011

Healthy Subjects
Healthy participants between the ages of 21 and 65 years old.

Primary Outcome Measures :
  1. To characterize changes in the diameter of retinal blood vessels to a light-induced flicker stimulus in healthy subjects on two separate visits. [ Time Frame: 1 Year ]

Secondary Outcome Measures :
  1. To compare retinal vasodilator responses to brachial reactive hyperemic responses. [ Time Frame: 1 Year ]

Information from the National Library of Medicine

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Ages Eligible for Study:   21 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
Healthy Subjects

Inclusion Criteria:

  • Healthy Individuals
  • Age: 21 to 65 years
  • Non-smokers
  • Non-obese

Exclusion Criteria:

  • History of cardiovascular, pulmonary, peripheral vascular disease, renal, prostate, and urinary retention disease; Hypertension; Narrow angle Glaucoma or Age Related Macular Degeneration.
  • Pregnancy
  • Inability to fixate using eye device
  • Does not wish to participate

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): NCT00783029

United States, Pennsylvania
Penn State Milton S. Hershey Medical Center
Hershey, Pennsylvania, United States, 17033
Sponsors and Collaborators
Penn State University
Principal Investigator: Kerstin Bettermann, MD, PhD Penn State College of Medicine

Responsible Party: Kerstin Bettermann, MD, PhD, Penn State University Identifier: NCT00783029     History of Changes
Other Study ID Numbers: HMC29113
IRB # 29113
First Posted: October 31, 2008    Key Record Dates
Last Update Posted: February 7, 2012
Last Verified: February 2012

Keywords provided by Kerstin Bettermann, Penn State University:
Vessel Reactivity
Dynamic Vessel Analyzer

Additional relevant MeSH terms:
Glucuronyl glucosamine glycan sulfate
Hypolipidemic Agents
Molecular Mechanisms of Pharmacological Action
Lipid Regulating Agents
Fibrinolytic Agents
Fibrin Modulating Agents
Hypoglycemic Agents
Physiological Effects of Drugs