Role of Endothelin- and Nitric Oxide-system in the Regulation of Optic Nerve Head Blood Flow During Changes in Ocular Perfusion Pressure
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ClinicalTrials.gov Identifier: NCT00406731 |
Recruitment Status :
Withdrawn
First Posted : December 4, 2006
Last Update Posted : August 15, 2019
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Tracking Information | ||||
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First Submitted Date ICMJE | November 30, 2006 | |||
First Posted Date ICMJE | December 4, 2006 | |||
Last Update Posted Date | August 15, 2019 | |||
Study Start Date ICMJE | January 2008 | |||
Actual Primary Completion Date | November 2014 (Final data collection date for primary outcome measure) | |||
Current Primary Outcome Measures ICMJE |
ONH pressure-flow relationship [ Time Frame: up to 3 study days ] | |||
Original Primary Outcome Measures ICMJE |
ONH pressure-flow relationship | |||
Change History | ||||
Current Secondary Outcome Measures ICMJE | Not Provided | |||
Original Secondary Outcome Measures ICMJE | Not Provided | |||
Current Other Pre-specified Outcome Measures | Not Provided | |||
Original Other Pre-specified Outcome Measures | Not Provided | |||
Descriptive Information | ||||
Brief Title ICMJE | Role of Endothelin- and Nitric Oxide-system in the Regulation of Optic Nerve Head Blood Flow During Changes in Ocular Perfusion Pressure | |||
Official Title ICMJE | Role of endothelin-and Nitric Oxide-system in the Regulation of Optic Nerve Head Blood Flow During Changes in Ocular Perfusion Pressure | |||
Brief Summary | Autoregulation is the ability of a vascular bed to maintain blood flow despite changes in perfusion pressure. The existence of an effective autoregulation in the optic nerve circulation has been shown in animals and humans. The exact mechanism behind this autoregulation is still unknown. The motive for the investigation of optic nerve head (ONH) blood flow autoregulation is to enhance the understanding of pathologic eye conditions associated with ocular vascular disorders. To clarify the regulatory mechanisms of ONH microcirculation is of critical importance to understand the pathophysiology of glaucoma because there is evidence that glaucoma is associated with optic nerve head ischemia. Several studies indicate that a disturbed autoregulation might contribute to glaucomatous optic neuropathy. Previous findings suggest endothelial dysfunction in glaucomatous optic neuropathy, in particular alterations in endothelin- and nitric oxide- system, which both play an important role in local regulation of vascular tone. In the present study, changes in ocular perfusion pressure will be performed during administration of drugs, which may potentially alter the pressure-flow relationship. These drugs include endothelin-1 and the nitric oxide synthase inhibitor NG-monomethyl-L-arginine (L-NMMA). |
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Detailed Description | Not Provided | |||
Study Type ICMJE | Interventional | |||
Study Phase ICMJE | Phase 2 | |||
Study Design ICMJE | Allocation: Randomized Intervention Model: Crossover Assignment Masking: Triple (Participant, Investigator, Outcomes Assessor) Primary Purpose: Treatment |
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Condition ICMJE |
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Intervention ICMJE |
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Study Arms ICMJE | Not Provided | |||
Publications * | Not Provided | |||
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline. |
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Recruitment Information | ||||
Recruitment Status ICMJE | Withdrawn | |||
Actual Enrollment ICMJE |
0 | |||
Original Enrollment ICMJE |
18 | |||
Actual Study Completion Date ICMJE | November 2014 | |||
Actual Primary Completion Date | November 2014 (Final data collection date for primary outcome measure) | |||
Eligibility Criteria ICMJE | Inclusion Criteria:
Exclusion Criteria:
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Sex/Gender ICMJE |
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Ages ICMJE | 18 Years to 35 Years (Adult) | |||
Accepts Healthy Volunteers ICMJE | Yes | |||
Contacts ICMJE | Contact information is only displayed when the study is recruiting subjects | |||
Listed Location Countries ICMJE | Austria | |||
Removed Location Countries | ||||
Administrative Information | ||||
NCT Number ICMJE | NCT00406731 | |||
Other Study ID Numbers ICMJE | OPHT-080206 | |||
Has Data Monitoring Committee | Yes | |||
U.S. FDA-regulated Product | Not Provided | |||
IPD Sharing Statement ICMJE | Not Provided | |||
Current Responsible Party | Gerhard Garhofer, Medical University of Vienna | |||
Original Responsible Party | Not Provided | |||
Current Study Sponsor ICMJE | Medical University of Vienna | |||
Original Study Sponsor ICMJE | Same as current | |||
Collaborators ICMJE | Not Provided | |||
Investigators ICMJE |
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PRS Account | Medical University of Vienna | |||
Verification Date | August 2019 | |||
ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP |