Progressive Open Angle Glaucoma (OAG) and Ocular Blood Flow

Study Overview
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Brief Summary
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The purpose of this study is to assess the correlation of vascular parameters, including genetic factors as well as ocular blood flow parameters against the progression rate of glaucomatous damage in patients with progressive OAG.

Detailed Description
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Glaucoma is one of the most common causes of blindness in the industrialized nations. For a long time glaucoma has been defined as a disease in which high intraocular pressure (IOP) leads to irreversible optic disc damage and subsequent visual field loss. However, recent investigations show that IOP is not the only factor that is involved in the glaucomatous process leading to retinal ganglion cell death. The role of vascular factors in the pathogenesis of glaucoma has recently received much attention based on animal experiments and epidemiological studies. Genes with products that are involved in the regulation of blood flow to ocular tissues may also be considered plausible candidates as a contributory factor in the development of glaucoma. Little is, however, known about a potential association between glaucomatous optic neuropathy and glaucomatous visual field defects and optic nerve head blood flow in patients with progressive open angle glaucoma (OAG). The current study seeks to gain insight into this association by assessing ocular blood flow parameters with a number of noninvasive technologies.

Official Title
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Genetic Vascular Risk Factors and Ocular Blood Flow in Patients With Progressive Open Angle Glaucoma (OAG)-a Longitudinal Prospective Study

Conditions
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Open Angle Glaucoma

Intervention / Treatment
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* Procedure: ocular blood flow measurement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Men and women over 40 years Unilateral or bilateral primary open angle glaucoma (POAG) or normal tension glaucoma (NTG) with visual defect, marked by an AGIS score (1994; 1. Study design and methods and baseline characteristics of study patient) of at least 1 but not more than 16 at the screening visit At least 3 reliable visual field tests in the eye that will be studied Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant Best-corrected visual acuity of 20/40 or better, spherical refraction within ± 3.0 diopters and cylinder correction within ± 3.0 diopters Exclusion Criteria: Evidence of secondary glaucoma, pseudoexfoliation, pigmentary dispersion Any form of retinal or neuroophthalmological disease that could result in visual field defects. Mean IOP > 30 mmHg, or any IOP > 35 mmHg in at least one eye History of acute angle closure Closed or barely open anterior chamber angle Topical or systemical/oral therapy with steroids Standard deviation of visual field testing > 10 Ocular inflammation or infection within the last three months Intraocular surgery or argon laser trabeculoplasty within the last six months 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 Symptoms of a clinically relevant illness in the 3 weeks before the first study day Blood donation during the previous 3 weeks Ametropia > 3 dpt

Ages Eligible for Study
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Minimum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Intervention/Treatment |
| --- |
|Procedure: ocular blood flow measurement|Retinal blood flow (with scanning laser Doppler flowmetry, laser Doppler velocimetry + retinal vessel analyzer) each measurement once on the study eye Choroidal blood flow (with laser Doppler flowmetry, laser interferometry, pneumotonometry) Frequency distribution of alleles of genetic markers for NOS3, more precisely eNOS -786CC polymorphism and of ET-1 (EDN1), and the receptors ETA (EDNRA), more precisely EDN1/+138/ex1 del/ins, EDN1/K198N, EDNRA/C+1222T, EDNRA/C+70G polymorphisms|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Optic nerve head blood flow (scanning laser Doppler flowmetry, laser Doppler flowmetry). |  | up to 6 years. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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genetic vascular risc factors, ocular blood flow, progressive glaucoma