A Study on the Efficacy and Safety of Multi-focal Scleral Contact Lens

Study Overview
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Brief Summary
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The rigid scleral contact lens with optical multi-focal design adopted in this study can focus the light in part of the optical area on the front of the retina to form myopic defocus, in order to delay the axial changes in children and adolescents with ultra-high myopia. In this study, RGP was used as a control, and a multicenter, randomized, controlled trial was conducted to verify the safety and effectiveness of multifocal scleral contact lenses for the correction of ultra-high myopia in children and adolescents.

Official Title
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A Multicenter Randomized Controlled Study on the Efficacy and Safety of Multi-focal Scleral Contact Lens in the Treatment of Ultra-high Myopia in Children and Adolescents

Conditions
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High Myopia

Intervention / Treatment
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* Device: Multi-focal rigid scleral contact lens
* Device: Rigid gas permeable contact lens


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Be able to understand and sign the informed consent when accompanied by parents or guardians. Age from 8 years old to15 years old. The equivalent spherical lens of both eyes after ciliary muscle paralysis is -5.00D to -20.00D, the astigmatism is ≤-3.50D. Willing to wear hard contact lenses, and able to wear only the hard contact lenses provided by the study as required and ensure adequate wearing duration. (6) Best corrected visual acuity of both eyes ≥ 0.8. Exclusion Criteria: (1) Allergic or intolerant to rigid contact lens or its care products or ciliary muscle paralysis drugs. Strabismus and/or amblyopia. (3) Those who have worn hard contact lenses in the past 30 days are using atropine, defocus frame lens, bifocal lens or progressive lens, acupuncture, etc. for myopia treatment. (4) Any clinically significant active eye disease, such as glaucoma, uveitis, chorioretinitis, central retinal artery or vein occlusion, and so on. (5) Patients with systemic diseases that may affect the wearing of hard contact lenses, such as hyperthyroidism, diabetes, mental illness, and so on. (6) are using drugs that affect their eye health. (7) History of eye injury or surgery. (8) Incapacitated or unable to follow the visitor as required. (9) Other conditions not suitable for inclusion as judged by the investigator.

Ages Eligible for Study
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Minimum Age: 8 Years
Maximum Age: 15 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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Multi-focal rigid scleral contact lens<br>During the study period, subjects will wear a multi-focal rigid scleral contact lens daily. | Device: Multi-focal rigid scleral contact lens<br>* True scleral lenses rest on the sclera and do not touch the cornea and limbus, leaving a clear area between the contact lens and the cornea.<br>* Other names: OVCTEK;|
| Active Comparator: Rigid gas permeable contact lens<br>During the study period, the subjects will wear rigid contact lenses daily | Device: Rigid gas permeable contact lens<br>* RGP contact lens is designed from a special rigid hydrophobic material. Patients wear RGP contact lens to form a contact lens-tear-cornea system to correct irregular astigmatism, reduce aberrations, provide good visual quality, and control the development of the disease through mild shaping effect.<br>* Other names: OVCTEK;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Axial length | Two-year change in axial length | 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| changes of spherical equivalent | Spherical equivalent as measured by cycloplegia autorefraction | 2 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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high myopia, children and adolescents, defocus, scleral contact lens