Water Drinking Test Study and Disc Hemorrhages in Normal Tension Glaucoma

Study Overview
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Brief Summary
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Disc hemorrhages are a known risk factor for progression of glaucoma. A positive water drinking test is also associated with progression of primary open glaucoma. The purpose of this study is to determine if patients with normal tension glaucoma and disc hemorrhages have a positive water drinking test. Patients with normal tension glaucoma and a disc hemorrhage will be recruited to undergo a water drinking test prior to any change in their treatment.

Detailed Description
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Patient with normal tension glaucoma under the care of a fellowship trained glaucoma specialist and noted to have a disc hemorrhage in one or both eyes when examined in the office will be recruited to undergo a water drinking test (WDT). After an informed consent is obtained, arrangements will be made to undergo the WDT either at the ophthalmologist's office or the local hospital clinic(Misericordia). The test will be administered in the following way: Upon arrival the patients baseline intraocular pressure (IOP) will be measured, then shortly afterwards the patient will drink 800 ml of water in a period of 5 minutes. Immediately after the water ingestion has finished a second IOP will be measured, followed by IOP measurements every 15 minutes for 60 minutes with a Goldman applanation tonometer by the same examiner. All of these measurements will be collected in a data sheet for the WTD. A total of 60 minutes would be the duration of the activity.

Official Title
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Correlation Between Water Drinking Test Study and Disc Hemorrhages in Normal Tension Glaucoma

Conditions
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Normal Tension Glaucoma

Intervention / Treatment
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* Diagnostic Test: water drinking test


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Clinical diagnosis of normal tension glaucoma by a fellowship trained glaucoma specialist, Clinical diagnosis of a disc hemorrhage diagnosed by a fellowship trained glaucoma specialist, Must be able to swallow water Must be able to be positioned to allow accurate measurement of the Intraocular pressure with a slit lamp mounted Goldmann applanation tonometer Must have a smooth corneal surface to allow for accurate Goldmann application tonometry measurement Outpatient A sufficient level of education to understand study procedures and be able to communicate with site personnel Exclusion Criteria: History of refractive surgery, Active ocular infection, Pregnancy, Cardiac or renal diseases, history of urinary retention, Corneal abnormalities preventing reliable IOP measurements, Previous trabeculectomy or glaucoma shunt surgery, Previous laser iridotomy, Cognitive impairment or language barrier preventing ability to provide an informed consent.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 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
Interventional Model Description: patients with a diagnosis of normal tension glaucoma and noted to have a disc hemorrhage
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: baseline Intraocular pressure<br>The participants will have their intraocular pressure measured with Goldmann Application Tonometry immediately prior to beginning the water drinking test. | |
| Active Comparator: Change in Intraocular pressure with Water drinking test<br>The participants will undergo the water drinking test as previously described, i.e. after drinking 800 mls of water over a 5 minute period, the intraocular pressure will be measured immediately after completion of ingestion, followed by intraocular pressure measurements every 15 minutes for 60 minutes, using etc Goldmann apllantion tonometer. | Diagnostic Test: water drinking test<br>* Water drinking test-glaucoma diagnostic test - marker for outflow facility reserve to detect IOP instability when the body ingests 800 ml of water within a 5 minute period of time<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in baseline intraocular pressure(IOP) with water drinking test | The change in intraocular pressure in patients with normal tension glaucoma and a disc hemorrhage after undergoing the water drinking test will be measured with Goldmann applanation tonometry. A change from baseline IOP of 5 mm Hg is considered abnormal . | The water drinking test takes 60 minutes, and the participant is then finished and can leave. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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normal tension glaucoma, disc hemorrhages, water drinking test