Effect of Oxygen Breathing on Flicker Induced Blood Flow Changes in the Optic Nerve Head - Full Text View

Sponsored by:	Medical University of Vienna
Information provided by:	Medical University of Vienna
ClinicalTrials.gov Identifier:	NCT00406224

Purpose

Background It has recently been shown that diffuse luminance flicker increases retinal and optic nerve head blood flow. This indicates that a neuro-vascular coupling between neural activity and blood flow exists as described previously for the brain. Although a lot of mediators such as NO, pO2, pCO2, H+ and K+ have been proposed, the mechanism of this coupling is still a matter of controversy. However, it has been shown in an animal experiment, that an increase in blood flow, evoked by diffuse luminance flicker stimulation is paralleled by an decrease in pO2 in the tissue. Thus, in this study we set out to investigate the flicker light induced increase in blood flow under elevated blood pO2.

Study rationale The motive for the investigation of retinal blood flow regulation is to enhance our understanding of the coupling mechanism between increased neural activity and blood flow in the retina in order to gain new insight in the pathophysiology of several eye diseases associated with ocular vascular disorders Study objectives To test the hypothesis whether oxygen breathing influences flicker light induced changes in optic nerve head blood flow

Condition	Intervention
Healthy	Drug: breathing 100% oxygen

U.S. FDA Resources

Study Type:	Interventional
Study Design:	Diagnostic, Non-Randomized, Open Label, Uncontrolled, Single Group Assignment, Efficacy Study

Further study details as provided by Medical University of Vienna:

Primary Outcome Measures:

Retinal vessel diameters

Study Start Date:	December 2002
Estimated Study Completion Date:	December 2003

Eligibility

Ages Eligible for Study:	19 Years and older
Genders Eligible for Study:	Male
Accepts Healthy Volunteers:	Yes

Criteria

Inclusion Criteria:

healthy volunteers

Exclusion Criteria:

Regular use of medication, abuse of alcoholic beverages, participation in a clinical trial in the 3 weeks preceding the study
Treatment in the previous 3 weeks with any drug
Symptoms of a clinically relevant illness in the 3 weeks before the first study day
Blood donation during the previous 3 weeks

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00406224

Sponsors and Collaborators

Medical University of Vienna

Investigators

Principal Investigator:

Gerhard Garhofer, MD

Medical University of Vienna

More Information

Study ID Numbers:	FliOxyGen
Study First Received:	November 30, 2006
Last Updated:	December 1, 2006
ClinicalTrials.gov Identifier:	NCT00406224
Health Authority:	Austria: Bundesministerium fuer Gesundheit

Study placed in the following topic categories:

Healthy

ClinicalTrials.gov processed this record on January 16, 2009