Corneal Biomechanics With Hydration in Normal and LASIK Eyes

Study Overview
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Brief Summary
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The research will utilize LASIK and non-LASIK populations to analyze the biomechanical differences between these corneas.

Detailed Description
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The research will utilize LASIK and non-LASIK populations to analyze the biomechanical differences between these corneas. Subjects' corneas will be swelled with warmed, humidified nitrogen using modified diving goggles to assess structural changes due to a two hour swelling period. Subjects will be examined prior to swelling by a registered ophthalmologist to ensure that the cornea is healthy enough to undergo the swelling procedure. Pre-swelling and post-swelling data will be compared for parameters such as elasticity, density, thickness, axial and tangential curvature, hydration, and intraocular pressure in the central, paracentral, and peripheral regions. Analysis of pre-swelling and post-swelling data will allow for a better understanding of the structural changes created by LASIK. In addition, this project will allow for a better understanding of how common fluctuations in hydration levels affect normal corneal parameters as given by common devices in both populations to allow for corrections for more accurate measurements.

Official Title
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Analysis of Corneal Biomechanics Based Upon Central and Peripheral Corneal Thickness in Normal and Post Refractive Surgery Eyes

Conditions
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Laser Corneal Surgery

Intervention / Treatment
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* Procedure: LASIK surgery
* Other: No Intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy cornea without LASIK surgery as determined by a registered ophthalmologist. Healthy cornea with LASIK surgery as determined by a registered ophthalmologist. Exclusion Criteria: Children under 18. Unhealthy cornea as determined by a registered ophthalmologist.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 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: Basic Science
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: non-LASIK<br>These participants have NOT had LASIK surgery. | Other: No Intervention<br>* Participant has healthy eyes not altered by LASIK surgery.<br>* Other names: no refractive surgery;|
| Active Comparator: LASIK<br>These participants have had LASIK surgery. | Procedure: LASIK surgery<br>* Participants have received LASIK surgery and their eyes are healthy.<br>* Other names: Refractive Surgery;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Corneal hydration (swelling) |  | Two hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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LASIK vs. non-LASIK