Myopia Preventing With Distance-image Screen

Study Overview
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Brief Summary
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This study is for testing the efficacy and safety of distance-image screens for preventing myopia in children for 12 month. Each subjects would be asked to paired test the ocular parameters between before and after 12-month distance-image screens.

Detailed Description
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This study is for testing the efficacy and safety of distance-image screens intended usage for preventing myopia in children with reading after a 6-meter-distant-image device. It was a prospective study. The investigators would like to recruit 100 volunteers, aged 6 years 16 in Beijing. All the volunteers will be complete examined their ocular parameters before using the distant-image screen in a random order for at least 2 hours daily for 12 month. The changes of ocular axial length and refractive error were both calculated before and after 12-month usage for paired t-test.

Official Title
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Clinically Study the Ocular Axial Length and Sphere Equivalence Changes of Children With Distance-image Screen Usage for One Year

Conditions
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Myopia, Progressive

Intervention / Treatment
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* Device: distance-image screen


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: (1) Must be 6 12 years old; (2) Must be best corrected visual acuity < logMAR: 0.1; (3) Spherical Equivalence (SE) must be -1.00  + 6.00 Diopter (D), (4) Spherical Equivalence (SE) must have changed > 1.25 Diopter (D) in the recent 2 years; (5) Must be astigmatism <1.75 Diopter (D); (6) Must be anisometropia <1.75 Diopter(D). Exclusion Criteria: (1) Strabismus disease; (2) Amblyopia disease; (3) Cataract disease; (4) Glaucoma disease; (5) Severe dry eye disease; (6) Cannot use distance-image screen for 12 month; (7) Other severe diseases that would effect the use of distance-image screen.

Ages Eligible for Study
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Minimum Age: 6 Years
Maximum Age: 12 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
Intervention Model: Single Group Assignment
Interventional Model Description: Paired testing those ocular parameters before and after 12-month usage of distance-image screen
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Distance -image screen<br>Distance -image screen is a device to make image in the distance of 6-meters when reading and learning at near. The investigators will ask the subjects to use the distance - image screen for 12 month | Device: distance-image screen<br>* Distance-image screen is a screen make each image at distance of 6-meters to reduce the accommodation and convergence for eyes during the reading and learning with screens.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes of ocular axial length (mm) | IntraOcularLens (IOL) master biometry will exam each eye before the testing and after the testing with distance-image screen | 12-month | 
| Changes of refractive error (D) | Cycloplegic refraction with autorefractor will test each eye before the testing and after the testing with distance-image screen | 12-month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes of center macular thickness (um) | Optic Coherent Topograph (OCT) of macular fovea central thickness will be made to compare the thickness before and after using distance-image screen | 12-month | 
| Changes of subretina choroidal thickness (um) | Optic Coherent Topograph (OCT) with Enhanced Depth Imaging (EDI) scan of macular fovea central thickness will be done to compare the thickness before and after using distance-image screen | at 12-month | 
| Changes of other regions choroidal thickness (um) | Optic Coherent Topograph (OCT) with Enhanced Depth Imaging (EDI) scan of other regions choroidal thickness will be done to compare the thickness before and after using distance-image screen | 12-month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Myopia; children