Optic Nerve Head Autoregulation During Changes in Arterial Blood Pressure

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Gerhard Garhofer, Medical University of Vienna
ClinicalTrials.gov Identifier:
NCT01663883
First received: January 24, 2012
Last updated: August 9, 2012
Last verified: August 2012

January 24, 2012
August 9, 2012
February 2012
April 2012   (final data collection date for primary outcome measure)
Optic nerve head blood flow [ Time Frame: 12 minutes ] [ Designated as safety issue: No ]
Same as current
Complete list of historical versions of study NCT01663883 on ClinicalTrials.gov Archive Site
  • Systolic/diastolic blood pressure [ Time Frame: 14 minutes ] [ Designated as safety issue: Yes ]
  • Intraocular pressure [ Time Frame: at baseline and minute 13 ] [ Designated as safety issue: No ]
  • Pulse rate [ Time Frame: 14 minutes ] [ Designated as safety issue: Yes ]
Same as current
Not Provided
Not Provided
 
Optic Nerve Head Autoregulation During Changes in Arterial Blood Pressure
Not Provided

Constant despite changes in perfusion pressure. It is observed in many vascular beds of the human body to prevent that variations in perfusion pressure are directly transmitted into changes in blood flow. This is necessary to prevent ischemia and/or hypoxia during decreased blood flow and bleeding or increased capillary pressure during increased blood flow.

In the eye, several studies have reported that retinal blood flow is autoregulated over a wide range of ocular perfusion pressures. Unfortunately only few data are available for the optic nerve head. To gain data about autoregulation is of special importance given that several important ocular diseases such as glaucoma and age-related macular degeneration are associated with impaired autoregulation. In humans most data were collected using laser Doppler flowmetry.

The present study aims to investigate the phenomenon of transient reduction in blood flow and to gain insight in the regulatory mechanisms of optic nerve head blood flow during isometric exercise.

Not Provided
Interventional
Not Provided
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Basic Science
Decreased Vascular Flow
Other: Isometric exercise
use of a handgrip for 3x2 minutes
Experimental: Healthy subjects
Intervention: Other: Isometric exercise
Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Completed
40
August 2012
April 2012   (final data collection date for primary outcome measure)

Inclusion Criteria:

  • Men and women aged between 18 and 35 years, nonsmokers
  • Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant
  • Normal ophthalmic findings, ametropia less than 3 diopters

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 (except oral contraceptives)
  • Symptoms of a clinically relevant illness in the 3 weeks before the first study day
  • Blood donation during the previous 3 weeks
Both
18 Years to 35 Years
Yes
Contact information is only displayed when the study is recruiting subjects
Austria
 
NCT01663883
OPHT-210911
Yes
Gerhard Garhofer, Medical University of Vienna
Medical University of Vienna
Not Provided
Principal Investigator: Gerhard Garhöfer, MD Department of Clinical Pharmacology, Medical University of Vienna
Medical University of Vienna
August 2012

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP