Exposure to Man-made Visible Light
Conditions
Brief summary
This study evaluates 670 nm energy in the form of red light to stimulate blood flow changes in healthy adults. All participants will receive red light to their leg. They will also receive a continuous infusion of Definity (octafluoropropane) ultrasound contrast.
Detailed description
670 nm energy in the form of red light dilates isolated blood vessels. This study seeks to measure vessel dilation in human subjects exposed to this energy at different irradiance intensities (25 milliwatts (mW)/cm2 and 75 mW/cm2). The intent of this protocol is to measure blood flow in the gastrocnemius muscle before and after exposure to 670 nm light energy. This protocol will be performed in healthy subjects, who do not meet exclusion criteria. The study consists of one visit. Blood flow measurement will be performed using contrast enhanced ultrasound, a method by which ultrasound contrast is continuously infused into the blood stream. Ultrasound records images in the area of interest and flow is related to the intensity of the contrast in each image. After baseline blood flow images are collected, the subject will receive red light energy to the gastrocnemius muscle with concurrent blood flow measurements with contrast ultrasound. The subject will be monitored post procedure and the study will then be completed.
Interventions
670 nm light emitting diode will be placed 1 cm above the gastrocnemius muscle. The diode will not be in direct contact with the skin. Subjects will be exposed to 75 mW/cm2.
Octofluoropropane will be administered as a continuous infusion prior to the initiation of 670 nm light in order to measure skeletal muscle blood flow.
Sponsors
Study design
Eligibility
Inclusion criteria
* Participants will be healthy subjects over the age of 18. * Men and women will be recruited for participation. * All ethnicities will be included in this study.
Exclusion criteria
Exclusionary criteria include: * age under 18 years and those over 60 years of age, * those who are unable to understand the consent process, * those who cannot read or speak English, * a history of cancer, * peripheral artery disease, * diabetes mellitus, * active pregnancy, * hypersensitivity to perflutren contrast agents, * pulmonary hypertension, * chronic kidney disease, * active tobacco or drug use, * blood pressure over 160/90, BMI\>30, * sickle cell disease, or * history of intracardiac shunt. Additional
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in blood flow (using octafluoropropane infusion and ultrasound) | 10 minutes | Blood flow changes based on ultrasound imaging |
Countries
United States
Contacts
Medical College of Wisconsin