Waveform Analysis of the Doppler Curve of Ophthalmic Arteries in Glaucoma Patients

February 5, 2013 updated by: Universitaire Ziekenhuizen KU Leuven

Waveform Analysis of the Doppler Curve of Ophthalmic Arteries in Primary Open-angle and Normal Tension Glaucoma Patients

Color Doppler Imaging (CDI) has been providing information about ocular blood flow over the past decades. This non-invasive procedure based on ultrasound technique has identified increased resistance and decreased systolic blood velocities to exist in the ophthalmic arteries of glaucoma patients. However, existing data has provided very little information regarding the analysis of the Doppler waveform in itself and to whether variables such as early systolic acceleration or systolic/diastolic velocity ratios are of any significance in glaucoma disease. In other medical specialties using CDI technology, such as nephrology or cardiology for instance, this analysis has been part of the normal routine. This information has been used in screening patients for disturbed circulation such as arterial stenosis or providing information regarding prognosis of renal and hepatic transplants have been used for decades now.

What is the normal characteristics of the waveform Doppler analysis? To answer this, the investigators will create a normative database using healthy controls.

Are there signs of altered stiffness or compliance in the ophthalmic arteries of glaucoma patients? To answer this, the analysis of early acceleration acceleration and detection of an early peak systolic will be done on the Doppler curves of glaucoma patients and compared to the healthy normative database.

Are there any difference between the two types of glaucoma [primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG)]? The investigators will compare the variables of the ophthalmic artery waveform in these two groups.

Do any of these Doppler waveform variables have any clinical significance? To answer this, the investigators will search for the existence of any correlation between the waveform data and both functional (visual field testing) and structural (Confocal scanning laser ophthalmoscopy - CSLO) variables of the glaucoma groups.

Study Overview

Status

Completed

Detailed Description

1. Color Doppler imaging of the ophthalmic artery will be performed 2. Visual field testing will be done 2. CSLO will be done

Study Type

Observational

Enrollment (Actual)

150

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

      • Leuven, Belgium
        • Department of Ophthalmology, UZLeuven

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Sampling Method

Probability Sample

Study Population

primary care clinic

Description

Inclusion Criteria:

  • • individuals over 18 years old

    • willing to sign an informed consent and able to comply with the requirements of the study
    • having no other ocular diseases besides glaucoma

Exclusion Criteria:

  • • history of ocular trauma

    • intraocular surgery (except for cataract surgery)
    • eye disease (except glaucoma)
    • systemic diseases with ocular involvement like diabetes

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
normal tension glaucoma patients
primary open angle glaucoma patients
healthy age matched controls

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Early Systolic Acceleration as a measure of vascular disfunction of the ophthalmic arteries in glaucoma patients
Time Frame: hospital stay, average 3 hours
Color Doppler Imaging of the ophthalmic artery will provide the waveform of the vessel. There will be a operator-dependent identification of the slope at the beggining of the cardiac cycle and a quantification of the early systolic acceleration. This numberical data will then be compared between healthy and glaucoma groups. Such variables will further be compared to the clinical data (functional - visual field defects and structural - CSLO).
hospital stay, average 3 hours

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Ratio between systolic and diastolic blood flow velocities as a measure of arterial compliance of the ophthalmic artery in glaucoma patients
Time Frame: Hospital stay, average 3 hours
Using the CDI-provided ophthalmic artery waveform, there will be an operator-dependent analysis of systolic and diastolic mean blood flow velocities. the ratio between these two variables will be calculated and the numerical data obtained will be compared between the healthy and glaucoma groups. Such ratio will furthermore be compared to functional and structural damage (visual field damage and CSLO, respectively).
Hospital stay, average 3 hours

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

September 1, 2011

Primary Completion (Actual)

December 1, 2011

Study Completion (Actual)

December 1, 2011

Study Registration Dates

First Submitted

November 29, 2011

First Submitted That Met QC Criteria

December 5, 2011

First Posted (Estimate)

December 7, 2011

Study Record Updates

Last Update Posted (Estimate)

February 6, 2013

Last Update Submitted That Met QC Criteria

February 5, 2013

Last Verified

September 1, 2011

More Information

Terms related to this study

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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