Choroidal Thickness During Changes in Intraocular Pressure and Arterial Blood Pressure - Full Text View

Purpose

Age-related macular degeneration (AMD) and glaucoma are among the leading causes of blindness in the western world. Elevated intraocular pressure (IOP) is a well known major risk factor for glaucoma. In addition, there is growing evidence that vascular factors, including arterial hypertension and hypotension, may play a role in the pathogenesis of AMD and glaucoma. To gain more insight into these mechanisms in humans is the primary goal of the present study.

Optical coherence tomography (OCT) delivers three dimensional, volumetric reflectivity information through transparent media in vivo. Moreover, the images show a high choroidal penetration and a resolution comparable to an histologic examination when infrared light sources are used. Because of its non-invasive character, OCT provides an ideal method for diagnosis and monitoring of retinal and choroidal abnormalities.

The present study aims to investigate whether choroidal thickness is temporarily altered by changes in IOP or systemic hemodynamic parameters. IOP will be increased by the use of a suction cup technique, mean arterial blood pressure will be altered by intravenously administered Phenylephrine or Sodium-Nitroprusside.

Condition	Intervention
Healthy	Drug: Phenylephrine Drug: Sodium-Nitroprusside Device: Suction Cup Device: Goldmann applanation tonometer Device: 1060nm Optical coherence tomography

Study Type:	Interventional
Study Design:	Allocation: Randomized Endpoint Classification: Safety/Efficacy Study Intervention Model: Crossover Assignment Masking: Double Blind (Subject, Investigator, Outcomes Assessor) Primary Purpose: Basic Science
Official Title:	Choroidal Thickness During Changes in Intraocular Pressure and Arterial Blood Pressure

Resource links provided by NLM:

Drug Information available for: Phenylephrine Phenylephrine hydrochloride Oxymetazoline Oxymetazoline hydrochloride Sodium nitroprusside Nitroprusside

U.S. FDA Resources

Further study details as provided by Medical University of Vienna:

Primary Outcome Measures:

Choroidal thickness [ Time Frame: 18 months ] [ Designated as safety issue: No ]

Secondary Outcome Measures:

Systolic/diastolic blood pressure (non-invasive) [ Time Frame: 18 months ] [ Designated as safety issue: Yes ]
Intraocular pressure (IOP) [ Time Frame: 18 months ] [ Designated as safety issue: No ]

Estimated Enrollment:	12
Study Start Date:	October 2012
Estimated Primary Completion Date:	March 2013 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
Active Comparator: Sodium-Nitroprusside Nipruss®, Sanol-Schwarz, Monheim, Germany 0, 0.5, 1 and 2 µg/kg/min, each infusion step for 5 minutes, total infusion period of 20 minutes	Drug: Phenylephrine Neosynephrine®, Winthrop Breon Laboratories New York, NY, USA 0, 0.5, 1 and 2 μg/kg/min, each infusion step for 5 minutes, total infusion period of 20 minutes Drug: Sodium-Nitroprusside Nipruss®, Sanol-Schwarz, Monheim, Germany 0, 0.5, 1 and 2 µg/kg/min, each infusion step for 5 minutes, total infusion period of 20 minutes Device: Suction Cup experimental stepwise increase of intraocular pressure while measurement of choroidal thickness suction force of 25, 50, 75, and 100 mmH Device: Goldmann applanation tonometer intraocular pressure measurements Device: 1060nm Optical coherence tomography Optical coherence tomography is a widely used non-invasive method to image the retina and choroid. Using a 1060nm light source coupled to a commercially available OCT system (Heidelberg Engineering, Heidelberg, Germany) allows for the measurement of choroidal thickness
Active Comparator: Phenylephrine Neosynephrine®, Winthrop Breon Laboratories New York, NY, USA 0, 0.5, 1 and 2 μg/kg/min, each infusion step for 5 minutes, total infusion period of 20 minutes	Drug: Phenylephrine Neosynephrine®, Winthrop Breon Laboratories New York, NY, USA 0, 0.5, 1 and 2 μg/kg/min, each infusion step for 5 minutes, total infusion period of 20 minutes Drug: Sodium-Nitroprusside Nipruss®, Sanol-Schwarz, Monheim, Germany 0, 0.5, 1 and 2 µg/kg/min, each infusion step for 5 minutes, total infusion period of 20 minutes Device: Suction Cup experimental stepwise increase of intraocular pressure while measurement of choroidal thickness suction force of 25, 50, 75, and 100 mmH Device: Goldmann applanation tonometer intraocular pressure measurements Device: 1060nm Optical coherence tomography Optical coherence tomography is a widely used non-invasive method to image the retina and choroid. Using a 1060nm light source coupled to a commercially available OCT system (Heidelberg Engineering, Heidelberg, Germany) allows for the measurement of choroidal thickness
Active Comparator: Suction Cup suction force of 25, 50, 75, and 100 mmHg	Drug: Phenylephrine Neosynephrine®, Winthrop Breon Laboratories New York, NY, USA 0, 0.5, 1 and 2 μg/kg/min, each infusion step for 5 minutes, total infusion period of 20 minutes Drug: Sodium-Nitroprusside Nipruss®, Sanol-Schwarz, Monheim, Germany 0, 0.5, 1 and 2 µg/kg/min, each infusion step for 5 minutes, total infusion period of 20 minutes Device: Suction Cup experimental stepwise increase of intraocular pressure while measurement of choroidal thickness suction force of 25, 50, 75, and 100 mmH Device: Goldmann applanation tonometer intraocular pressure measurements Device: 1060nm Optical coherence tomography Optical coherence tomography is a widely used non-invasive method to image the retina and choroid. Using a 1060nm light source coupled to a commercially available OCT system (Heidelberg Engineering, Heidelberg, Germany) allows for the measurement of choroidal thickness

Eligibility

Ages Eligible for Study:	18 Years to 35 Years
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	Yes

Criteria

Inclusion Criteria:

Men and women aged between 18 and 35 years, nonsmokers
Men and women will be included in equal parts
Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant
Normal findings in the laboratory testings unless the investigator considers an abnormality to be clinically irrelevant
Normal ophthalmic findings, ametropia less than 1 diopter

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 History of hypersensitivity to the trial drugs or to drugs with a similar chemical structure
History or presence of gastrointestinal, liver or kidney disease, or other conditions known to interfere with distribution, metabolism or excretion of study drugs
History of migraine
Pregnancy

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT01333891

Contacts

Contact: Gerhard Garhöfer, MD, PD

0043140400 ext 2981

gerhard.garhoefer@meduniwien.ac.at

Locations

Austria
Department of Clinical Pharmacology, Medical University of Vienna	Not yet recruiting
Vienna, Austria, 1090

Sponsors and Collaborators

Medical University of Vienna

Investigators

Principal Investigator:

Gerhard Garhöfer, MD, PD

Department of Clinical Pharmacology, Medical University of Vienna

More Information

No publications provided

Responsible Party:	Gerhard Garhofer, Assoc. Prof. Priv. Doz. Dr., Medical University of Vienna
ClinicalTrials.gov Identifier:	NCT01333891 History of Changes
Other Study ID Numbers:	OPHT-151010
Study First Received:	April 11, 2011
Last Updated:	August 9, 2012
Health Authority:	Austria: Agency for Health and Food Safety

Additional relevant MeSH terms:

Nitroprusside
Phenylephrine
Oxymetazoline
Vasodilator Agents
Cardiovascular Agents
Therapeutic Uses
Pharmacologic Actions
Nitric Oxide Donors
Molecular Mechanisms of Pharmacological Action
Antihypertensive Agents
Adrenergic alpha-1 Receptor Agonists
Adrenergic alpha-Agonists
Adrenergic Agonists

Adrenergic Agents
Neurotransmitter Agents
Physiological Effects of Drugs
Cardiotonic Agents
Mydriatics
Autonomic Agents
Peripheral Nervous System Agents
Sympathomimetics
Vasoconstrictor Agents
Nasal Decongestants
Respiratory System Agents
Protective Agents

ClinicalTrials.gov processed this record on May 16, 2013