Optic Nerve Head Autoregulation During Changes in Arterial Blood Pressure

Decreased Vascular Flow Clinical Trial

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01663883
• Other study ID #: OPHT-210911
• Status: Completed
• Phase: N/A
• First received: January 24, 2012
• Last updated: August 9, 2012
• Start date: February 2012
• Est. completion date: August 2012

Study information

• Verified date: August 2012
• Source: Medical University of Vienna
• Contact: n/a
• Is FDA regulated: No
• Health authority: Austria: Agency for Health and Food Safety
• Study type: Interventional

Clinical Trial Summary

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 40
• Est. completion date: August 2012
• Est. primary completion date: April 2012
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 18 Years to 35 Years

Eligibility

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

Study Design

Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Basic Science

Related Conditions & MeSH terms

• Decreased Vascular Flow

Intervention

Other:
• Isometric exercise
use of a handgrip for 3x2 minutes

Locations

Country	Name	City	State
Austria	Department of Clinical Pharmacology	Vienna

Sponsors (1)

Lead Sponsor	Collaborator
Medical University of Vienna

Country where clinical trial is conducted

Austria, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Optic nerve head blood flow		12 minutes	No
Secondary	Systolic/diastolic blood pressure		14 minutes	Yes
Secondary	Intraocular pressure		at baseline and minute 13	No
Secondary	Pulse rate		14 minutes	Yes