Impact of Color Correcting Lenses on Color Vision Deficiency

Study Overview
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Brief Summary
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To demonstrate improved color vision in subjects with color vision deficiencies while wearing color-correcting lenses and after color-correcting lense use.

Detailed Description
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The long term objective of this study is to extend upon research demonstrating improvements in color vision deficiencies (CVDs) while wearing color-correcting lenses (CCLs) and after wearing CCLs. Recordings of brainwaves and eye-waves will be made to assess the retina, optic nerve and brain in order to localize where adaptive changes in the visual system are occurring in response to wearing CCLs.

Official Title
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Immediate and Extended Wear Impact of Color Correcting Lenses on Color Vision Deficiency

Conditions
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Color Blindness, Green, Color Blindness, Red, Color Blindness, Color Vision Defects

Intervention / Treatment
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* Device: Experimental Group 1: Color Correcting Lenses
* Device: Placebo Group 1: Placebo Lenses
* Device: Placebo Group 1 Crosses over to become Experimental Group 2: Color Correcting Lenses
* Device: Experimental Group 1 Crosses over to become Placebo Group 2: Placebo Lenses
* Device: Color Correcting Lenses in Subjects with Normal Color Vision


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: no reported history of eye, systemic or ocular disease VA of 20/30 in each eye hereditary color vision deficient (CVDs) verified by failing scores on the red-green anomaloscope (outside system normal range) and Ishihara testing (3 or more errors on 14 testable plates) color vision normal (CVNs) verified by passing red-green anomaloscope (outside system normal range) and Ishihara testing (3 or more errors on 14 testable plates) Exclusion Criteria: reported use of sleep-inducing or wakefulness drugs

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: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Double blind randomized crossover trial
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Color Vision Deficient with Color Correcting Lenses<br>10 subjects confirmed to have hereditary color vision deficiency randomly assigned to experimental group 1 which includes baseline testing with and without color correcting lenses, followed by 7 days of wear, minimum 3 hours/day, followed by retesting with and without color correcting lenses. | Device: Experimental Group 1: Color Correcting Lenses<br>* Color Correcting Lenses<br>|
| Placebo Comparator: Color Vision Deficient with Placebo Lenses<br>10 subjects confirmed to have hereditary color vision deficiency randomly assigned to Placebo Group 1 which includes baseline testing with and without placebo lenses, followed by 7 days of wear, minimum 3 hours/day, followed by retesting with and without placebo lenses. | Device: Placebo Group 1: Placebo Lenses<br>* Placebo Lenses<br>|
| Experimental: Crossover: Placebo to Experimental<br>Placebo Group 1 crosses over to become Experimental Group 2 which includes baseline testing with and without color correcting lenses, followed by 7 days of wear, minimum 3 hours/day, followed by retesting with and without color correcting lenses. | Device: Placebo Group 1 Crosses over to become Experimental Group 2: Color Correcting Lenses<br>* Color Correcting Lenses<br>|
| Placebo Comparator: Crossover: Experimental to Placebo<br>Experimental Group 1 crosses over to become Placebo Group 2 which includes baseline testing with and without placebo lenses, followed by 7 days of wear, minimum 3 hours/day, followed by retesting with and without placebo lenses. | Device: Experimental Group 1 Crosses over to become Placebo Group 2: Placebo Lenses<br>* Placebo Lenses<br>|
| Active Comparator: Control Group: Subjects with Normal Color Vision<br>Fifteen subjects confirmed to have normal color vision will be tested in a single session to determine whether color correcting lenses affect color vision in color vision normal subjects and to provided normative data for several unique measures of color vision performance | Device: Color Correcting Lenses in Subjects with Normal Color Vision<br>* Color Correcting Lenses<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cone Contrast Test | Cone Contrast Sensitivity (CS) Test (CCT, Innova Systems, Inc.): red, green & blue cone CS using 100-point scale based on log changes in CS. Values will be converted to Z-scores to compare to outcomes with other units. | 2 WeekS | 
| Cone Contrast Naming Test | Red, green & blue cone CS and color naming accuracy each based on 100-point scale. Values will be converted to Z-scores to compare to outcomes with other units. | 2 Weeks | 
| Letter Chart Testing | Letter chart cone specific VA, small letter CS, and large letter CS scored as number of letters correct with VA expressed as log MAR & CS as log CS. Values will be converted to Z-scores to compare to outcomes with other units. | 2 Weeks | 
| Color Matching | Cone specific color matching provides the contrast seen by the normal cone type which matches the contrast seen by the defective cone type in units of % Weber contrast. Values will be converted to Z-scores to compare to outcomes with other units. | 2 Weeks | 
| Color Identification Test | Cockpit color identification test measure reaction time in seconds and error rate to identify colored targets on a computer display. Values will be converted to Z-scores to compare to outcomes with other units. | 2 Weeks | 
| Visual Electrodiagnostic Testing | Cone specific visual brainwaves (VEPs) and flash and pattern eye waves (ERGs) will be quantified in terms of amplitude in microvolts and latency in msec. Values will be converted to Z-scores to compare to outcomes with other units. | 2 Weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Color-Correcting Lenses