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Measurement of Retinal Blood Flow, Retinal Oxygenation and Retinal Oxygen Extraction in Healthy Subjects During Normoxia and Systemic Hyperoxia

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Gerhard Garhofer, Medical University of Vienna
ClinicalTrials.gov Identifier:
NCT00914407
First received: June 4, 2009
Last updated: March 9, 2017
Last verified: March 2017
  Purpose
The inner retina is crucially dependent on an adequate retinal blood supply. When the retina becomes ischemic and hypoxic this results in severe vision loss due to retinal neovascularization. Measurement of retinal blood flow and retinal oxygenation is, however, still a difficult task. Information on retinal oxygenation is almost unavailable from human studies. In the present protocol the investigators propose a procedure allowing for the measurement of retinal blood flow, retinal oxygenation and retinal oxygen extraction by combining a number of innovative techniques. Specifically, retinal vessel diameters will be measured with a Retinal Vessel Analyzer, retinal blood velocities with bi-directional laser Doppler velocimetry and retinal oxygenation with spectroscopic evaluation of retinal fundus images. This will allow for the calculation of retinal oxygen extraction, a fundamental parameter of retinal function. Up to now, no data for retinal oxygen extraction are available in the literature.

Condition Intervention
Healthy Normoxia Systemic Hypoxia Drug: Oxygen

Study Type: Interventional
Study Design: Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: Measurement of Retinal Blood Flow, Retinal Oxygenation and Retinal Oxygen Extraction in Healthy Subjects During Normoxia and Systemic Hyperoxia

Resource links provided by NLM:


Further study details as provided by Gerhard Garhofer, Medical University of Vienna:

Primary Outcome Measures:
  • Retinal blood velocity Retinal vessel diameters Oxygen saturation of retinal vessels Oxygen extraction as calculated from these parameters [ Time Frame: 20 min ocular blood flow measurement on 1 study day ]

Enrollment: 48
Study Start Date: April 2010
Study Completion Date: March 1, 2017
Primary Completion Date: December 10, 2016 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Healthy subjects Drug: Oxygen
100% Oxygen inhalation for 30 minutes

  Eligibility

Ages Eligible for Study:   18 Years to 35 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Men and women aged between 18 and 35 years
  • Nonsmokers
  • Body mass index between 15th and 85th percentile
  • Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant
  • Normal laboratory values unless the investigator considers an abnormality to be clinically irrelevant
  • Normal ophthalmic findings, ametropia < 3 Dpt

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
  • Pregnancy
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00914407

Locations
Austria
Department of Clinical Pharmacology, Medical University of Vienna
Vienna, Austria, 1090
Sponsors and Collaborators
Medical University of Vienna
  More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Gerhard Garhofer, Assoc. Prof. Priv.-Doz. Dr, Medical University of Vienna
ClinicalTrials.gov Identifier: NCT00914407     History of Changes
Other Study ID Numbers: OPHT-030209
Study First Received: June 4, 2009
Last Updated: March 9, 2017

Keywords provided by Gerhard Garhofer, Medical University of Vienna:
Ocular physiology

Additional relevant MeSH terms:
Hyperoxia
Signs and Symptoms, Respiratory
Signs and Symptoms

ClinicalTrials.gov processed this record on August 17, 2017