Horizontal vs. Vertical Positioning of the iCare Rebound Tonometer and Effects on Intraocular Pressure Readings

Study Overview
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Brief Summary
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The goal of this study is to evaluate the agreement between intraocular pressure (IOP) measurements taken by iCare, held in both vertical and horizontal positions. In addition, iCare measurements will be compared against pneumotonometry measurements to assess for accuracy.

Official Title
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Horizontal vs. Vertical Positioning of the iCare Rebound Tonometer and Effects on Intraocular Pressure Readings

Conditions
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Intraocular Pressure

Intervention / Treatment
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* Other: Horizontal iCare
* Other: Vertical iCare


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18 years of age or older Must be able to understand and sign and informed consent form that has been approved by an Institutional Review Board/Ethics Committee Exclusion Criteria: Evidence of corneal epithelial defects or pathology affecting corneal rigidity Use of topical ophthalmic medications (except for artificial tears) History or corneal surgeries Any condition that would prevent or inhibit intraocular pressure measurements using iCare or pneumotonometry Evidence of ocular infection 30 days prior to enrollment Allergy to proparacaine or latex

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Horizontal iCare<br>In the horizontal iCare arm, these patients were randomized to have their IOP measured with the iCare tonometer held in the horizontal position first and then their IOP measured with the iCare tonometer held in the vertical position. | Other: Horizontal iCare<br>* IOP of the right eye will be measured using the iCare tonometer held in the horizontal position first and then in the vertical position.<br>Other: Vertical iCare<br>* IOP of the right eye will be measured using the iCare tonometer held in the vertical position first and then in the horizontal position.<br>|
| Active Comparator: Vertical iCare<br>In the vertical iCare arm, these patients were randomized to have their IOP measured with the iCare tonometer held in the vertical position first and then their IOP measured with the iCare tonometer held in the horizontal position. | Other: Horizontal iCare<br>* IOP of the right eye will be measured using the iCare tonometer held in the horizontal position first and then in the vertical position.<br>Other: Vertical iCare<br>* IOP of the right eye will be measured using the iCare tonometer held in the vertical position first and then in the horizontal position.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| IOP taken by iCare - horizontal |  | 1 Day | 
| IOP taken by iCare - vertical |  | 1 Day | 
| IOP taken by pneumatonometer |  | 1 Day |