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Non-invasive Measurement of Retinal Blood Flow Based on Vessel Analysis and Fourier Domain Optical Coherence Tomography in Patients With Hypertensive Retinopathy

This study is currently recruiting participants. (see Contacts and Locations)
Verified December 2016 by Medical University of Vienna
Sponsor:
Information provided by (Responsible Party):
Gerhard Garhofer, Medical University of Vienna
ClinicalTrials.gov Identifier:
NCT01753648
First received: December 7, 2012
Last updated: December 1, 2016
Last verified: December 2016
  Purpose

Recently, a new and sophisticated method for assessment of retinal blood flow and retinal blood flow velocity profiles has become available. This technique is based on the combination of measurement of retinal vessel calibers with bidirectional Fourier domain optical coherence tomography (FDOCT). The valid measurement of retinal blood flow is of significant importance, because it is known that major ophthalmic diseases, such as hypertensive retinopathy, are associated with alterations in blood flow.

Hypertensive retinopathy is the most common manifestation of arterial hypertension in the eye. Elevated systemic blood pressure leads to generalized arteriolar narrowing caused by vasospasms and increased vascular tone. Further in the disease process, focal arteriolar narrowing, retinal haemorrhages, hard exudates and cotton wool spots can occur. Previous studies have shown that blood flow in the extraocular vessels and in the choroid is compromised in patients with arterial hypertension. However, data on the impact of arterial hypertension on retinal blood flow and retinal blood flow velocities are lacking.

The present study sets out to compare total retinal blood flow and retinal velocity profiles in patients with hypertensive retinopathy and healthy age- and sex-matched controls. Ocular perfusion pressure will be calculated based on measurements of blood pressure and intraocular pressure to allow for calculation of vascular resistance. In addition, velocity profiles at arterio-venous crossings will be measured. It is hypothesized that these velocity profiles are considerably modified in patients with stage 2 and 3 hypertensive retinopathy compared to healthy controls because of pronounced arterio-venous compression.


Condition Intervention
Hypertensive Retinopathy
Device: Dynamic Vessel Analyzer
Other: FDOCT
Other: Ocular perfusion pressure

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: Single Blind (Outcomes Assessor)
Primary Purpose: Basic Science
Official Title: Non-invasive Measurement of Retinal Blood Flow Based on Vessel Analysis and Fourier Domain Optical Coherence Tomography in Patients With Hypertensive Retinopathy

Resource links provided by NLM:


Further study details as provided by Medical University of Vienna:

Primary Outcome Measures:
  • Total retinal blood flow [ Time Frame: 1 day ]

Secondary Outcome Measures:
  • Retinal vessel diameter [ Time Frame: 1 day ]
  • Retinal blood velocities [ Time Frame: 1 day ]
  • Ocular perfusion pressure [ Time Frame: 1 day ]
  • Retinal (arterial and venous) oxygen saturation [ Time Frame: 1 day ]

Estimated Enrollment: 60
Study Start Date: January 2015
Estimated Study Completion Date: October 2017
Estimated Primary Completion Date: September 2017 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: hypertensive retinopathy
30 patients with hypertensive retinopathy stage 2 or 3
Device: Dynamic Vessel Analyzer
Retinal vessel diameter, total retinal blood flow (together with FD-OCT), retinal oxygen saturation
Other: FDOCT
total retinal blood flow (together with DVA), retinal blood velocities
Other Name: Fourier Domain Color Doppler Optical Coherence Tomography
Other: Ocular perfusion pressure
Measurement of intraocular pressure and mean arterial blood pressure for determination of ocular perfusion pressure
Experimental: healthy controls
30 healthy age- and sex-matched controls
Device: Dynamic Vessel Analyzer
Retinal vessel diameter, total retinal blood flow (together with FD-OCT), retinal oxygen saturation
Other: FDOCT
total retinal blood flow (together with DVA), retinal blood velocities
Other Name: Fourier Domain Color Doppler Optical Coherence Tomography
Other: Ocular perfusion pressure
Measurement of intraocular pressure and mean arterial blood pressure for determination of ocular perfusion pressure

  Eligibility

Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

Inclusion criteria for healthy subjects

  • Men and women aged over 18 years
  • Non-smokers
  • Normal findings in the medical history unless the investigator considers an abnormality to be clinically irrelevant
  • Systolic Blood Pressure ≤ 120 mmHg and Diastolic Blood Pressure ≤ 80 mmHg
  • Normal ophthalmic findings, ametropia < 6 Dpt.

Inclusion criteria for patients with hypertensive retinopathy

  • Men and women aged over 18 years
  • Hypertensive retinopathy stage 2 or 3
  • Normal ophthalmic findings except hypertensive retinopathy stage 2 and 3, ametropia < 6 Dpt.

Exclusion Criteria:

Any of the following will exclude a healthy subject from the study:

  • Symptoms of a clinically relevant illness in the 3 weeks before the first study day
  • Presence or history of a severe medical condition as judged by the clinical investigator
  • Presence or history of arterial hypertension
  • Regular use of medication, abuse of alcoholic beverages, participation in a clinical trial in the 3 weeks preceding the study (except oral contraceptive)
  • Blood donation during the previous three weeks
  • Presence of any abnormalities preventing reliable measurements in the study eye as judged by the investigator
  • Ametropia >= 6 Dpt
  • Pregnancy, planned pregnancy or lactating

Any of the following will exclude a patient with hypertensive retinopathy from the study:

  • Participation in a clinical trial in the 3 weeks preceding the screening visit
  • Symptoms of a clinically relevant illness in the 3 weeks before the first study day
  • Presence or history of a severe medical condition as judged by the clinical investigator
  • Blood donation during the previous three weeks
  • Hypertensive retinopathy stage 4
  • Presence of any abnormalities preventing reliable measurements in the study eye as judged by the investigator
  • Ametropia >= 6 Dpt
  • Pregnancy, planned pregnancy or lactating
  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: NCT01753648

Contacts
Contact: Gerhard Garhoefer, MD +43140400 ext 2981 gerhard.garhoefer@meduniwien.ac.at

Locations
Austria
Department of Clinical Pharmacology, Medical University of Vienna Recruiting
Vienna, Austria, 1090
Contact: Gerhard Garhoefer, MD    +43140400 ext 2981    gerhard.garhoefer@meduniwien.ac.at   
Principal Investigator: Katarzyna Napora, MD         
Sponsors and Collaborators
Medical University of Vienna
  More Information

Responsible Party: Gerhard Garhofer, Assoc. Prof. PD Dr., Medical University of Vienna
ClinicalTrials.gov Identifier: NCT01753648     History of Changes
Other Study ID Numbers: OPHT-220612
Study First Received: December 7, 2012
Last Updated: December 1, 2016

Keywords provided by Medical University of Vienna:
retinal blood flow
retinal blood velocity
retinal oxygen saturation
retinal vessel diameter
ocular perfusion pressure

Additional relevant MeSH terms:
Retinal Diseases
Hypertensive Retinopathy
Eye Diseases
Hypertension
Vascular Diseases
Cardiovascular Diseases
Glucuronyl glucosamine glycan sulfate
Anticoagulants
Hypolipidemic Agents
Antimetabolites
Molecular Mechanisms of Pharmacological Action
Lipid Regulating Agents
Fibrinolytic Agents
Fibrin Modulating Agents
Hypoglycemic Agents
Physiological Effects of Drugs

ClinicalTrials.gov processed this record on April 24, 2017