A Real-world Study of 650nm Low-intensity Single-wavelength Red Light for Children and Adolescents

Study Overview
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Brief Summary
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To evaluate the efficacy and safety of 650nm low-level red-light irradiation for myopia control and prevention in children under less restrictive conditions than randomized controlled trials. Participants included children(aged 7 to 18 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 real world study will be conducted in at least 100 hospitals: Beijing Tongren Hospital will be the initiator of the study, other hospitals such as the Capital Institute of Pediatrics will serve as sub-centers. The whole study will last for three years.The investigators will perform data analysis at 6 months follow-up, one-year follow-up, and two-year follow-up. Participants who used 650 nm low-level red-light would be recruited. 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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A Real-world Study to Evaluate the Efficacy of 650nm Low-intensity Single-wavelength Red Light in the Prevention and Control of Myopia in Children and Adolescents

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 7 to 18 years The cycloplegic spherical equivalent error (SER) is +0.5D or less 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: Including but not limited to the following eye diseases: strabismus, amblyopia, ocular tumors, glaucoma/macular disease and other fundus diseases (including heredity), keratitis, eye trauma, uveitis Including but not limited to the following systemic diseases: epilepsy, tumor, heart disease, asthma, systemic immune diseases, infectious diseases Mental diseases Similar interventions have been used in the past year Allergic to cycloplegic agents or to red light The 650nm red light intervention was not suitable for the condition evaluated by the researchers are currently using atropine or similar drugs, or have stopped using them for less than 1 month

Ages Eligible for Study
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Minimum Age: 7 Years
Maximum 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 650 nm low-level red-light<br>Children who are exposed to the 650 nm low-level red-light will be recruited into the cohort, the exposure factor is red-light irradiation. The study does not give interventions, but only recruit children who received or who is receiving the 650 nm low-level red-light intervention for observation. | Device: 650 nm low-level red-light<br>* Typically, children who uses the 650 nm low-level red-light will be recruited into this study. The use of any other myopia intervention is not restricted except for low concentrations of atropine. Because atropine will cause pupils dilated, the amount of light entering the eye can not be controlled, and red-light is a laser, to be safe, we need to take certain consideration of the amount of light-entering. Participants receive the 650 nm low-level red-light intervention not because they are enrolled in a study, they would receive the intervention in the same manner and intensity if they were not enrolled in the study.<br>|

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 | 
| 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 | 

Secondary Outcome Measures

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