Effectiveness and Safety of Partition Multi-point Defocused Myopia Management Spectacle Lens in Myopia Control

Study Overview
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Brief Summary
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Myopia is considered to be the most common type of refractive error, and the incidence of myopia has shown a trend of low age. Recent studies found that the new aspheric microlens spectacle lens can more effectively control the progress of diopter than the single-vision spectcale lens. A new technology of equivalent defocusing around the lens called the partition multi-point defocus optical technology is adopted in this study.

Detailed Description
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Myopia is considered to be the most common type of refractive error, and it has increased rapidly worldwide. The vision damage caused by uncorrected myopia seriously affects the quality of life, may lead to poor academic performance of children, and cause considerable economic burden. About 90% of vision damage caused by myopia can be prevented by cost-effective interventions or treatment. In recent years, the incidence of myopia has shown a trend of low age. Therefore, clinical intervention should be carried out in the childhood stage, which is the key period of eye development, to control the progress of myopia. A recent 2-year randomized controlled study in China found that the new aspheric microlens myopia control spectacle lens can more effectively control the progress of diopter than the single-vision spectcale lens. Different studies have found or proved the technical principle of the new aspheric defocusing microlens. Animal experiments found that the direction, intensity and regional distribution of optical defocus signals have a substantial impact on the growth of eyes; The diopter of peripheral relative hyperopia can affect the central myopia; The changes of myopia and optical defocus in the nasal and temporal regions can change the shape and peripheral refraction of the eyes; Local changes in the effective focus of the eye will lead to regional changes in eye growth and refractive error. Based on the findings of animal experiments, the new technology of equivalent defocusing around the lens called the partition multi-point defocus optical technology is adopted in this study. A prospective, single-center, open-label, non-inferiority randomized controlled trial is developed to evaluate the effectiveness and safety of partition multi-point defocused myopia management spectacle lens among children in China in myopia control.

Official Title
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Effectiveness and Safety of Partition Multi-point Defocused Myopia Management Spectacle Lens in Myopia Control Compared With Spectacle Lenses With Aspherical Lenslets: a Randomised Non-inferiority Trial

Conditions
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Myopia

Intervention / Treatment
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* Other: Partition defocus myopia management spectacle lens
* Other: Spectacle lenses with aspherical lenslets


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged 8 to 13 years; Under the condition of bilateral cycloplegic autorefraction, the spherical refractive error of -0.75 to -4.75 D in each eye and astigmatism of not more than 1.50 D and anisometropia of not more than 1.00 D; Best-corrected visual acuity of equal or better than 0.00 LogMAR (>= 1.0 as Snellen). The intraocular pressure of 10 to 21mmHg. Volunteer to participate in this clinical trial with signature of the informed consent form. Exclusion Criteria: History of eye injury or intraocular surgery; Clinically abnormal slit-lamp findings Abnormal fundus examination Ocular disease, such as uveitis and other inflammatory diseases, glaucoma, cataract, fundus diseases, eye tumors, dominant strabismus, and any eye diseases that affect visual function; Systemic diseases causing low immunity (such as diabetes, Down's syndrome, rheumatoid arthritis, psychotic patients or other diseases that researchers think are not suitable for wearing glasses); Participation of the drug clinical trial within three month and the device clinical trial within one month; Only one eye meets the inclusion criteria; Unable to have regular follow-up Participation of any myopia control clinical research trial within three months, and currently using rigid contact lenses (including nursing products), multifocal contact lenses, progressive multifocal lenses and other specially designed myopia control lenses, atropine drugs, 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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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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intervention group<br>The participants wear the partition defocus myopia management spectacle lens. | Other: Partition defocus myopia management spectacle lens<br>* Participants in the intervention group will receive the partition defocus myopia management spectacles lens and receive follow-up checks.<br>|
| Active Comparator: Control group<br>spectacle lenses with aspherical lenslets | Other: Spectacle lenses with aspherical lenslets<br>* Participants in the control group will receive the spectacle lenses with aspherical lenslets and receive follow-up checks.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes of spherical equivalent refraction (SER) at two years | The difference of SER (Diopter) at two years from baseline. SER will be measured every year after cycloplegia. | 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes of axial length (AL) at two years | The difference of AL (mm) at two years from baseline. AL will be measured every half year by IOLMaster700. | 2 years | 
| Change of anterior chamber depth (ACD) at two years | The difference of ACD（mm） at two years from baseline. ACD will be measured every half year by IOLMaster700. | 2 years | 
| Change of lens thickness (LT) at two years | The difference of LT (mm) at two years from baseline. LT will be measured every half year by IOLMaster700. | 2 years | 
| Change of corneal power (CP) at two years | The difference of CP (Diopter) at two years from baseline. CP will be measured every half year by IOLMaster700. | 2 years | 
| Best corrected visual acuity at two years | Best corrected visual acuity measured every year by EDTRS visual acuity chart after cycloplegia. | 2 years | 
| Binocular visual function at two years | Binocular visual function which will be measured every year is a qualitative outcome assessed by a series of tests. | 2 years | 
| Choroidal thickness at two years | The difference of Choroidal thickness (μm) at two years from baseline. Choroidal thickness will be measured every year by OCTA. | 2 years | 
| Visual scale score at six months | Visual scale score measured by the Chinese version of the pediatric refractive error profile2 (PREP2) and scaled from 0 (poor quality of life) to 100 (good quality of life). | 6 months | 
| Visual scale score at two years | Visual scale score measured by the Chinese version of the pediatric refractive error profile2 (PREP2) and scaled from 0 (poor quality of life) to 100 (good quality of life). | 2 years | 
| Time length of wearing spectcales at two years | Time length of wearing spectcales collected every half year. Participants report the approximate time of wearing glasses per day and the days of wearing glasses per week. | 2 years | 
| Safty of wearing the spectacle lens | Safty of wearing the spectacle lens which is a qualitative outcome will be evaluated every half year by prespecified measures and definations based on symptoms and signs, intraocular pressure，slit lamp and ocular fundus checks. | 2 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Partition multi-point defocused, Myopia control