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Measurement of Total Retinal Blood Flow During Flicker Stimulation in Healthy Subjects

NCT02531399 · Status: COMPLETED · Phase: NA · Type: INTERVENTIONAL · Enrollment: 20

Last updated 2017-09-06

No results posted yet for this study

Summary

Neurovascular coupling or functional hyperemia is defined as an essential physiologic mechanism in the brain, which is necessary for the local adaption of blood flow to altered metabolic demands of the tissue. It has been shown that also in the eye, blood flow is considerably coupled to retinal neural activity. The current concept of functional hyperemia is that visual stimulation, as flicker light, effectuates increasing neural activity in the retina, which elevates the metabolic needs of the retinal tissue for oxygen and glucose and consequently induces dilatation and augmented blood flow in the retinal vasculature. In several studies, stimulation with flicker light has been shown to induce an increase of blood flow in major retinal arteries and veins as well as an increase of optic nerve head blood flow. Up until now, flicker induced changes in blood flow were measured solely in the major retinal arteries and veins with systems such as the commercially available dynamic vessel analyzer (DVA) by Imedos and with laser Doppler velocimetry (LDV).

In the present study, the investigators propose to measure the response of total retinal blood flow to diffuse luminance flicker stimulation with bi-directional Fourier Domain Doppler Optical Coherence Tomography (FDOCT) as well as with Laser Speckle Flowgraphy (LSFG) in healthy subjects by assessing vessel diameter, blood velocity and blood flow of all retinal vessels. For comparative reasons, the investigators will furthermore assess the blood flow of major retinal arteries and veins with the dynamic vessel analyzer (DVA) and laser Doppler velocimetry (LDV).

Conditions

  • Healthy

Interventions

DEVICE

LDV

Measurement of retinal blood velocities

DEVICE

DVA

Measurement of retinal vessel diameters

DEVICE

LSFG

Imaging of retinal blood flow

DEVICE

FDOCT

Measurement of retinal blood velocities

Sponsors & Collaborators

  • Medical University of Vienna

    lead OTHER

Principal Investigators

  • Gerhard Garhoefer, MD · Department of Clinical Pharmacology, Medical University of Vienna

Study Design

Allocation
NA
Purpose
BASIC_SCIENCE
Masking
NONE
Model
SINGLE_GROUP

Eligibility

Min Age
18 Years
Max Age
45 Years
Sex
ALL
Healthy Volunteers
Yes

Timeline & Regulatory

Start
2015-10-31
Primary Completion
2017-08-31
Completion
2017-09-30

Countries

  • Austria

Study Locations

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Read the full study record

This page highlights key information. For complete eligibility criteria, study locations, investigator contacts, and the full protocol, visit the original record on ClinicalTrials.gov.

View NCT02531399 on ClinicalTrials.gov