Myopia Control With the Multi-segment Lens

Study Overview
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Brief Summary
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The purpose of this study is to determine if the Multiple-Segment (MS) spectacle lens can slow myopia progression in Hong Kong schoolchildren. MS lens is also called Defocus Incorporated Multiple Segments (DIMS) spectacle lens

Detailed Description
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MS lens is a novel lens designed in attempt to slow myopia progression. It is a multifocal spectacle lens which corrects distance refractive error and at the same time produces myopic defocus images on the retina for all distances. The myopic defocus aims at slowing down myopia progression. The purpose of this study is to investigate if the MS lens can slow myopia progression in Hong Kong Chinese schoolchildren. The subjects will be randomly assigned to either treatment group (wear MS lenses) or control group (wear ordinary single vision lenses). Their cycloplegic refraction and axial length will be monitored every six months over 2 years. The changes in refractive errors and axial length in two groups will be compared.

Official Title
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The Clinical Trial of Myopia Control in Schoolchildren Using the Multi-segment (MS) Lens

Conditions
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Myopia

Intervention / Treatment
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* Device: Multiple-Segment spectacle lens


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age at enrolment: 8-13 year Spherical equivalent refractions (SER): -1.00 to -5.00 Dioptres (D) Astigmatism and anisometropia of 1.50 D or less Spectacle corrected monocular logMAR visual acuity: 0 or better 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: Single vision spectacle lens<br>Single vision lens with power for correcting distance refraction. | |
| Experimental: Multiple-Segment spectacle lens<br>A multifocal spectacle lens that corrects distance refraction and provides myopic defocus at the same time. | Device: Multiple-Segment spectacle lens<br>* A multifocal spectacle lens that corrects distance refraction and provides myopic defocus images simultaneously. The myopic defocus aims at slowing down myopia progression.<br>* Other names: MS lens;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cycloplegic Refraction Change in SER | Change in cycloplegic SER (in diopter) that was measured using Shin-Nippon NVision-K 5001 autorefractor. | Baseline and 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Axial Length | Axial length (mm) was measured after cycloplegia using IOL Master | Baseline and 2 years |