The Effect of Blue-light Filtering Spectacle Lenses on Myopia Progression in Schoolchildren

Study Overview
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Brief Summary
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The purpose of this study is to investigate if the blue-light filtering spectacle lenses promote myopia progression in schoolchildren.

Detailed Description
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The effect of blue light on ocular health has been studied extensively. Shorter wavelength such as blue light could cause damage to the retina. The damage was more evident in the ageing eye. Since the tablets and mobile with blue LED backlight display are widely used, thus blue-light filtering spectacle lenses are now available in the market. However, whether this kind of lenses could affect the eye growth in schoolchildren is unknown. This study is then designed to investigate if the blue-light filtering spectacle lenses affect myopia progression in Hong Kong Chinese schoolchildren. The schoolchildren will be randomly allocated to either blue-light filtering spectacle lens group (treated) or conventional spectacle lens group (control). Their axial length and refraction will be monitored every 6 months for 2 years. The changes between two group will then be compared.

Official Title
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Does Blue-light Filtering Spectacle Lens Promote Myopia Progression in Schoolchildren

Conditions
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Myopia

Intervention / Treatment
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* Device: Blue-light filtering spectacle lenses


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Refraction: myopia of -1.00 dioptres (D) to -5.00D Astigmatism: equal or less than -1.50D Anisometropia: equal or less than 1.00D Best corrected monocular visual acuity: 0.0 LogMAR or better after full correction Parents' understanding and acceptance of random allocation of grouping Exclusion Criteria: any ocular and systemic abnormalities might affect visual functions or refractive development prior treatment of myopic control, e.g. drugs, orthokeratology, progressive addition lenses, bifocal lenses, drugs (e.g. atropine), etc.

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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Conventional anti-reflection coated spectacle lens<br>Single vision lenses with correction of distant refraction and conventional anti-reflection coating | |
| Experimental: Blue-light filtering spectacle lenses<br>Single vision lenses with correction of distant refraction and blue-light filtering coating | Device: Blue-light filtering spectacle lenses<br>* This is a single vision spectacle lens for correction of distant refractions and filtering out the blue light by providing anti-blue light coating.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cycloplegic refraction | Refraction done under cycloplegia | 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Axial length | Length of eyeball that is directly related to myopia | 2 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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blue light filtering spectacle lens