650nm Low-level Red-light for Myopia Control and Prevention in Children

Study Overview
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Brief Summary
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A multicenter randomized controlled trial, evaluating the efficacy and safety of 650nm low-level red-light irradiation for myopia control and prevention in children. Participants included children(aged 6 to 12 years, spherical equivalent error of 0.5D or below) who are already myopic at recruitment, and those who are of Emmetropia or low hyperopia.

Detailed Description
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This multicenter randomized controlled trial will be conducted in three hospitals: Beijing Tongren Hospital, and another two subcenters. The whole study will last for five years.The investigators will perform data analysis at 6 months follow-up, one-year follow-up, two-year follow-up, three-year follow-up, four-year follow-up and the end of the study. The intervention measure used will be 650 nm low-level red-light. This kind of intervention will be integrated into a headworn device. This device could be used for treatment of myopia or amblyopia, and is safe for the eyes and has been verified by the Chinese market supervision and administration department.

Official Title
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Repeated Exposure to 650nm Low-level Red-light for Myopia Control and Prevention in Children: A Randomized Controlled Trial

Conditions
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Myopia

Intervention / Treatment
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* Device: 650 nm low-level red-light


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Children aged 6 to 12 years The cycloplegic spherical equivalent error (SER) is -6D to 1D (> -6D, ≤1D) in both eyes Astigmatism of 2.5 D or less (≤2.5D) Willing to participate in the study and sign the informed consent form Exclusion Criteria: Using other myopia interventions or stopped using them for less than three months, including but not limited to atropine eye drops or orthokeratology lens With anisometropia (difference in sphere between two eyes was 1.5D or greater), strabismus, or amblyopia With refractive media opacification (keratopathy, lens opacity, etc.) Allergy to cycloplegia drugs

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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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 650 nm low-level red-light, plus single vision spectacle lenses<br>Children in the treatment group are expected to receive 6 minutes irradiation of 650 nm low-level red-light daily, divided into two times a day, each lasting for 3 minutes. Single vision spectacle lenses are allowed for myopic children. | Device: 650 nm low-level red-light<br>* 650 nm low-level red-light is a kind of laser, concentrated into a beam, to repeatedly irradiate the retina<br>|
| No Intervention: Control<br>Single vision spectacle lenses are allowed for myopic children. No intervention was given. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in axial length | Use an optical biometer to measure the axial length. | Baseline, six-month follow-up, one-year follow-up, two-year follow-up, three-year follow-up, four-year follow-up, five-year follow-up | 
| Change in spherical equivalent error | Children's pupil were dilated using Mydrin-P eye drops, and then the refractive error was measured using an autorefractor. the two measurements (axial length and spherical equivalent error) will be aggregated to arrive at one reported value through the following way: axial enlongation will be defined as progress in myopia, decrease in spherical equivalent error will be defined as progress in myopia too. | Baseline, six-month follow-up, one-year follow-up, two-year follow-up, three-year follow-up, four-year follow-up, five-year follow-up | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Choroid thickness | Use an enhanced-depth imaging technique (based on Optical coherence tomography ) | Baseline, six-month follow-up, one-year follow-up, two-year follow-up, three-year follow-up, four-year follow-up, five-year follow-up | 
| Change in steep keratometry | Use an optical biometer | Baseline, six-month follow-up, one-year follow-up, two-year follow-up, three-year follow-up, four-year follow-up, five-year follow-up | 
| Change in flat keratometry | Use an optical biometer | Baseline, six-month follow-up, one-year follow-up, two-year follow-up, three-year follow-up, four-year follow-up, five-year follow-up | 
| Change in length thickness | Use an optical biometer | Baseline, six-month follow-up, one-year follow-up, two-year follow-up, three-year follow-up, four-year follow-up, five-year follow-up | 
| Change in anterior chamber depth | Use an optical biometer | Baseline, six-month follow-up, one-year follow-up, two-year follow-up, three-year follow-up, four-year follow-up, five-year follow-up | 
| Change in central corneal thickness | Use an optical biometer | Baseline, six-month follow-up, one-year follow-up, two-year follow-up, three-year follow-up, four-year follow-up, five-year follow-up |