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

This study has been completed.
Information provided by (Responsible Party):
Kerstin Bettermann, Penn State University Identifier:
First received: October 30, 2008
Last updated: February 6, 2012
Last verified: February 2012
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.


Study Type: Observational
Study Design: Observational Model: Case-Only
Time Perspective: Prospective
Official Title: Reproducibility of Dynamic Vessel Analyzer Measurements and Establishment of Standards

Further study details as provided by Kerstin Bettermann, Penn State University:

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

Enrollment: 87
Study Start Date: October 2008
Study Completion Date: December 2011
Primary Completion Date: December 2011 (Final data collection date for primary outcome measure)
Healthy Subjects
Healthy participants between the ages of 21 and 65 years old.

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.

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
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Please refer to this study by its identifier: 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
  More Information

Responsible Party: Kerstin Bettermann, MD, PhD, Penn State University Identifier: NCT00783029     History of Changes
Other Study ID Numbers: HMC29113
IRB # 29113
Study First Received: October 30, 2008
Last Updated: February 6, 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 processed this record on September 19, 2017