Red Light Intervention for Myopia Prevention

Study Overview
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Brief Summary
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To explore the effectiveness of using low-intensity single-wavelength red light to prevent myopia in schoolchildren, and to provide a feasible scheme for reducing the incidence of myopia.

Official Title
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A Randomized Controlled Trial of Low-dose Single-wavelength Red Light in the Decrease of Myopia Incidence Rate in the Setting of School.

Conditions
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Myopia

Intervention / Treatment
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* Device: LLLT（Low Level Laser Therapy）


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Students of grade 1-4 in the participating schools; Students' eyes have no myopia, that is the cycloplegic spherical equivalent（SE） >-0.50D, and at least one eye accords with the pre-myopic state, that is -0.50D <cycloplegic SE≤0.50D; Students whose mother and/or father are in myopia status (SE < -3.0D for either of eyes); Students whose parents sign informed consent and agree to let their kids participate in baseline screen and follow-up examinations and surveys. Exclusion Criteria: Students whose parents do not sign informed consent; Students who have strabismus and/or other binocular vision abnormality; Students who have other eye diseases and/or systematic diseases; Students who have DC <=-1.5D; Students whose difference of SE between the two eyes >=1.5D; Students who meet the standards with which investigators and study physicians think it is not appropriate to enroll.

Ages Eligible for Study
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Minimum Age: 6 Years
Maximum Age: 11 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intervention<br>Red light irradiation was conducted at school from Monday to Friday and at home everyday in summer and winter holiday twice a day for 3 minutes per time, with an interval of 4 hours | Device: LLLT（Low Level Laser Therapy）<br>* 2 times a day, 3 minutes each time, with an interval of more than 4 hours. During the semester: From Monday to Friday, set up an intervention room in the school; For winter and summer vacation: everyday at home<br>|
| No Intervention: Control<br>No intervention | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| One-year cumulative incidence of myopia (%) in the intervention group and the control group. | Myopia is defined as the cycloplegic spherical equivalent of either eye ≤-0.5D | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The progress of spherical equivalent(SE,D) of children in intervention group and control group. | The spherical equivalent(SE,D) will be measured by autorefractor(KR-8900, Topcon). | 1 year | 
| The progress of axial length of children in intervention group and control group. | The axial length will be measured using IOLMaster. | 1 year | 
| The progress of choroidal thickness in children in pre-myopia state in intervention group and control group. | The choroidal thickness will be measured using SS-OCT. | 1 year | 
| The change of uncorrected visual acuity (UCVA) of children in intervention group and control group. | The uncorrected visual acuity (UCVA) will be measured using a mounted and illuminated E chart of the Early Treatment Diabetic Retinopathy study (ETDRS) charts. | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Children and adolescents, Myopia, Prevention and control, Red light