Myopia:the Role of Cone Opsin Mutations & Glasses That Control Axial Elongation

Study Overview
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Brief Summary
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To determine the effect of spectacles with a red blocking filter on myopia progression in children. To determine the effect of spectacles with a holographic diffuser that spreads incident light rays over an angle of 0.5 degrees on myopia progression in children To determine the combined effects of spectacles with a red blocking filter and a diffuser that spreads incident light over an angle of 0.5 degrees on myopia progression in children.

Detailed Description
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In this clinical trial we will determine whether commercially available lens tints that are normally used for cosmetic purposes or for blocking sunlight have a beneficial effect of slowing axial eye growth in children with myopia when used alone or in conjunction with a holographic diffuser that blurs the image slightly. The following procedures will be performed on a total of 240 children from 8 to 13 years of age: Color vision tests (Richmond Hardy-Rand-Rittler pseudoisochromatic plate test and/or the Rayleigh match test and/or the Neitz Test of Color Vision), and machine-based vision tests using the Titmus tester (color vision, binocularity, acuity, and heterophoria tests); each subject will provide a blood sample or a buccal swab for genetic analysis of the long and middle wavelength cone photopigment genes in order to determine the relationship between the cone opsins and myopia; eye measurements including axial length and corneal curvature will be performed using the Zeiss Intraocular Lens Master; cycloplegic autorefraction will be doe at the beginning of the study before participants start wearing the study spectacles, after 18 months if wearing the study spectacles, and 6 months after participants stop wearing the study spectacles. 4) subjects will be randomly assigned to one of four groups, consisting of 60 subjects each, each group will be assigned one of four study spectacles. The study spectacles for all participants will have the optimal lens corrections for both eyes. Group 1 participants will wear spectacles with lenses tinted to blocks red light. Group 2 participants will wear spectacles with lenses that have a holographic diffuser on surface of and that are tinted to reduce the light intensity by the same amount that the red-blocking tint does. Group 3 participants will wear spectacles that are tinted to block red light and that have a holographic diffuser. Group 4 participants will wear spectacles that are tinted to reduces the light intensity by the same amount that the red-blocking tint does. Participants will wear the study glasses for 18 months. Axial length measurements will be taken twice prior to when subjects begin wearing the glasses and once every three month thereafter.

Official Title
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Myopia:the Role of Cone Opsin Mutations & Glasses That Control Axial Elongation

Conditions
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Myopia

Intervention / Treatment
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* Other: Spectacles with red-blocking tint
* Other: Spectacles with holographic diffuser and color neutral tint
* Other: Spectacles with holographic diffuser and red-blocking tint
* Other: Spectacles with color neutral tint


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: nearsighted having a refractive error of at least -0.5 diopters myopia progression at least -.50 D per year in previous year astigmatism and anisometropia not more than 1.5 D distance monocular acuity 6/6 or better near monocular acuity of 0.4 M or better stereoacuity not more than 40 sec of arc at 40 cm able to respond to subjective testing no contact lens use during the study able to comply with wearing the experimental lenses daily for 18 months able to have axial length measurements accurately on the Zeiss Intraocular Lens Master willing to donate a blood sample or a buccal swab for genetic analysis can be refracted to 20/20 or 20/15 Exclusion Criteria: glaucoma, amblyopia, strabismus ocular disease developmental delay history of wearing bifocal lenses any type of eye surgery color vision deficiency

Ages Eligible for Study
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Minimum Age: 8 Years
Maximum Age: 13 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: color blocking tint<br>Spectacles with red-blocking tint subjects will wear glasses daily for 6 months and have | Other: Spectacles with red-blocking tint<br>* Eyeglasses will have lenses that will correct refractive error for each subject, and will have a tint that blocks red light.<br>|
| Other: holographic diffuser<br>Spectacles with color neutral tint subjects will wear glasses daily for 6 months and have | Other: Spectacles with holographic diffuser and color neutral tint<br>* Eyeglasses will correct refractive error for each subject but will have a holographic diffuser applied to the surface and will have a color neutral filter to adjust the light intensity reaching the eyes to be the same as for groups 1 and3.<br>|
| Other: diffuser & color blocking tint<br>Spectacles with holographic diffuser and red-blocking tint subjects will wear glasses daily for 6 months and have | Other: Spectacles with holographic diffuser and red-blocking tint<br>* Eyeglasses will correct refractive error for each subject and will be tinted to block red light, and will have a holographic diffuser to blur the image.<br>|
| Other: holographic diffuser and neutral tint<br>Spectacles with holographic diffuser and color neutral tint subjects will wear glasses daily for 6 months and have | Other: Spectacles with color neutral tint<br>* Eyeglasses will correct refractive error for each subject and will have a color neutral tint to adjust the light intensity reaching the eyes so it is the same as for groups 1 and 3.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Myopia progression measured by rate of axial elongation of the eye | The axial length of both eyes will be measured before wearing the experimental eyeglasses, then once every three months thereafter for 18 months, and again 6 months after subjects stop wearing the study eye glasses. The rate of axial elongation will be calculated. | every 3 months for 18 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Myopia progression measured by cycloplegic autorefraction. | A cycloplegic autorefraction will be done at the beginning of the study before subjects start wearing the study glasses, after 18 months of wearing the study glasses,and again about 6 months after wearing the study glasses stopped. | 18 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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myopia, nearsightedness, axial elongation of the eye, refractive error