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

Completed

• Conditions: Healthy

• Registration Number: NCT00783029
• Lead Sponsor: 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.

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 Timeline

• Study Start: 2008-10
• Study First Submitted: 2008-10-30
• Study First Submitted QC: 2008-10-30
• Study First Posted: 2008-10-31
• Primary Completion: 2011-12
• Study Completion: 2011-12
• Status Verified: 2012-02
• Last Update Submitted: 2012-02-06
• Last Update Posted: 2012-02-07

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 87

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

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
To characterize changes in the diameter of retinal blood vessels to a light-induced flicker stimulus in healthy subjects on two separate visits.	1 Year

Secondary Outcome Measures

Name	Time	Method
To compare retinal vasodilator responses to brachial reactive hyperemic responses.	1 Year

Trial Locations

Locations (1)

Penn State Milton S. Hershey Medical Center; 🇺🇸 Hershey, Pennsylvania, United States