Conjunctival Rebound After Scleral Lens Wear

Study Overview
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Brief Summary
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Scleral lenses, customized rigid contact lenses that land on the soft and spongy conjunctival tissue overlying the sclera, will be fitted on 15 subjects with normal ocular surfaces. The purpose of the study is to determine the amount of conjunctival compression caused by the devices and the length of time required for the shape to recover from compression.

Detailed Description
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The purpose of this study is to determine the interval required for the conjunctival tissue to return to its natural shape after scleral lens wear. All study visits will take place at the University of Houston College of Optometry (UHCO). Subjects will be recruited and fitted with scleral lenses to wear during the experimental days. Once the proper fit has been achieved, subjects will wear the scleral lens for 4 days total, returning after the 1st and 4th day of lens wear for approximately 2 hours of testing. The subjects will then return every 24-hours for measurements until their conjunctival shape has returned to the original shape. The testing will be done using the sMap scleral topographer, which measures the elevation of the conjunctiva. Testing is non-invasive although it requires instillation of Fluress eye drops, a sodium fluorescein dye with anesthetic that allows for imaging. The total number of visits is 9-14 and the length of visit ranges from 10 minutes to 2.5 hours.

Official Title
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Measuring the Recovery of the Conjunctival Tissue After 4 Days of Scleral Lens Wear

Conditions
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Conjunctival Diseases

Intervention / Treatment
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* Device: Scleral lens


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Normal ocular surface without conjunctival or scleral disease Male or female 18 years of age and older prior to the initial visit A non-scleral lens wearer. Exclusion Criteria: Individuals with anterior segment ocular pathology that may affect intraocular pressure and/or scleral/conjunctival health. Individuals with known adverse response to Fluress® ophthalmic drops Individuals with a history of habitual scleral lens wear If a usable baseline image is unable to be obtained at the initial visit due to small ocular surface area or eyelid anatomy Individuals currently taking any ocular medications that could affect intraocular pressure and/or scleral/conjunctival health Individuals who have any other conditions or situations which, in the investigator's opinion, may put the subject at significant risk, may confound study outcomes, or may significantly interfere with the subject's participation in the study

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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
Intervention Model: Single Group Assignment
Interventional Model Description: Prospective observational study
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Post-scleral lens wear<br>Normal subjects without ocular diseased who have worn scleral lenses for at least 8 hours. | Device: Scleral lens<br>* Scleral contact lenses, manufactured in rigid gas permeable fluorosilicone acrylate polymers and treated with plasma treatment prior to use.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rebound at 120 minutes post-SL removal, Day 4 | Conjunctival rebound amount at 120 minutes post-removal, Day 4 | Measured 120-130 minutes post-SL removal, Day 4 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rebound at 120-hours post-SL discontinuation | Conjunctival rebound amount at 120 hours post-removal | Measured 115-125 hours post-SL removal | 
| Rebound at 168-hours post-SL discontinuation | Conjunctival rebound amount at 168 hours post-removal | Measured 160-170 hours post-SL removal | 
| Rebound at 144-hours post-SL discontinuation | Conjunctival rebound amount at 144 hours post-removal | Measured 140-150 hours post-SL removal | 
| Rebound at 72-hours post-SL discontinuation | Conjunctival rebound amount at 72 hours post-removal | Measured 60-80 hours post-SL removal | 
| Rebound at 90 minutes post-SL removal, Day 4 | Conjunctival rebound amount at 90 minutes post-removal, Day 4 | Measured 90-100 minutes post-SL removal, Day 4 | 
| Rebound at 90 minutes post-SL removal, Day 1 | Conjunctival rebound amount at 90 minutes post-removal, Day 1 | Measured 90-100 minutes post-SL removal, Day 1 | 
| Rebound at 60 minutes post-SL removal, Day 4 | Conjunctival rebound amount at 60 minutes post-removal, Day 4 | Measured 60-70 minutes post-SL removal, Day 4 | 
| Rebound at 30 minutes post-SL removal, Day 1 | Conjunctival rebound amount at 30 minutes post-removal, Day 1 | Measured 30-40 minutes post-SL removal, Day 1 | 
| Rebound at 24-hours post-SL discontinuation | Conjunctival rebound amount at 24 hours post-removal | Measured 20-30 hours post-SL removal | 
| Rebound at 5 minutes post-SL removal, Day 1 | Conjunctival rebound amount at 5 minutes post-removal, Day 1 | Measured 5-10 minutes post-SL removal, Day 1 | 
| Rebound at 30 minutes post-SL removal, Day 4 | Conjunctival rebound amount at 30 minutes post-removal, Day 4 | Measured 30-40 minutes post-SL removal, Day 4 | 
| Rebound at 120 minutes post-SL removal, Day 1 | Conjunctival rebound amount at 120 minutes post-removal, Day 1 | Measured 120-130 minutes post-SL removal, Day 1 | 
| Rebound at 5 minutes post-SL removal, Day 4 | Conjunctival rebound amount at 5 minutes post-removal, Day 4 | Measured 5-10 minutes post-SL removal, Day 4 | 
| Rebound at 60 minutes post-SL removal, Day 1 | Conjunctival rebound amount at 60 minutes post-removal, Day 1 | Measured 60-70 minutes post-SL removal, Day 1 | 
| Rebound at 48-hours post-SL discontinuation | Conjunctival rebound amount at 48 hours post-removal | Measured 40-50 hours post-SL removal | 
| Rebound at 96-hours post-SL discontinuation | Conjunctival rebound amount at 96 hours post-removal | Measured 90-100 hours post-SL removal | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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scleral lenses