The Validity of Retinal Blood Flow Measurements During Hyperoxia in Humans Using Fourier Domain Color Doppler Optical Coherence Tomography (CDOCT)
Summary
Noninvasive monitoring of blood flow in retinal circulation may elucidate the progression and treatment of ocular disorders, including diabetic retinopathy, age-related macular degeneration and glaucoma.
Laser Doppler velocimetry (LDV), a noninvasive optical method combined with vessel size determination has been used extensively as a valuable research tool to examine blood flow dynamics in the human retina. However, no information on the velocity profile within the vessel is available. Ophthalmic color Doppler optical coherence tomography (CDOCT) provides laser Doppler information in addition to conventional optical coherence tomography, allowing the observation of blood flow dynamics simultaneously to imaging retinal structure.
We have recently demonstrated the feasibility of Fourier domain CDOCT to assess velocity profiles in human retinal vessels in vivo.
In the present study the validity of Fourier domain CDOCT for retinal blood flow measurements will be tested at baseline and during hyperoxia-induced vasoconstriction in humans by comparison with retinal blood flow measurements using a commercially available LDV system and the Zeiss retinal vessel analyzer (RVA)
Study Design
Allocation: Non-Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Diagnostic
Conditions
Healthy
Intervention
100% Oxygen
Location
Department of Clinical Pharmacology
Vienna
Austria
1090
Status
Completed
Source
Medical University of Vienna
Results (where available)
Links
- Source: http://clinicaltrials.gov/show/NCT00431600
- Information obtained from ClinicalTrials.gov on October 18, 2012
Medical and Biotech [MESH] Definitions
Oxygen Consumption
The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)
Oxygen Isotopes
Stable oxygen atoms that have the same atomic number as the element oxygen, but differ in atomic weight. O-17 and 18 are stable oxygen isotopes.
Reactive Oxygen Species
Molecules or ions formed by the incomplete one-electron reduction of oxygen. These reactive oxygen intermediates include SINGLET OXYGEN; SUPEROXIDES; PEROXIDES; HYDROXYL RADICAL; and HYPOCHLOROUS ACID. They contribute to the microbicidal activity of PHAGOCYTES, regulation of signal transduction and gene expression, and the oxidative damage to NUCLEIC ACIDS; PROTEINS; and LIPIDS.
Oxygen Radioisotopes
Unstable isotopes of oxygen that decay or disintegrate emitting radiation. O atoms with atomic weights 13, 14, 15, 19, and 20 are radioactive oxygen isotopes.
Singlet Oxygen
An excited state of molecular oxygen generated photochemically or chemically. Singlet oxygen reacts with a variety of biological molecules such as NUCLEIC ACIDS; PROTEINS; and LIPIDS; causing oxidative damages.
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