Defocus (DIMS) Spectacles Versus Ortho-K Lenses (OKL) for Slowing Myopia Progression in Danish Children Aged 6-12 Years.

Study Overview
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Brief Summary
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The purpose is to compare the myopia control efficacy of Ortho-K lenses (OKL) and Defocus (DIMS) spectacles in Danish myopic children aged 6-12 years. It is a clinical randomized non-inferiority trial, where the participants are randomly assigned to either OKL or DIMS spectacles. The participants are followed during 18 months of therapy. The hypotheses: There is no statistically significant difference between the myopia control efficacy between OKL and DIMS spectacles. Larger pupil size is positively correlated to treatment efficacy for both devises. Increasing choroidal thickness during early treatment is positively correlated to treatment efficacy for both devises. There is no difference in vision related quality of life between the two groups.

Official Title
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Defocus Incorporated Multiple Segment Spectacle Lenses (DIMS) Versus Orthokerathology Lenses (OKL) for Slowing Myopia Progression in Danish Children Aged 6-12 Years. The Noninferiority NISDO Study.

Conditions
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Myopia

Intervention / Treatment
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* Device: Defocus Incorporated Multiple Segment (DIMS) Spectacles
* Device: Orthokerathology lenses (OKL)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Myopic children aged 6 to 12 years. Myopia of the 6 to 8-year-olds: -1.00 to -4.75 D spherical component and up to -2.50 D of regular astigmatism. Myopia of the 9 to 12-year-olds: -2.00 to -4.75 D spherical component and up to -2.50 D of regular astigmatism. Anisometropia < 1,5 D cycloplegic spherical equivalent refractive error. Best corrected visual acuity: Age 6 to 8 (inclusive) years: 0.8 Snellen (equivalent to ≥ 3/5 letter on the 0.8 line = 78 ETDRS letters). Age 9 to 12 years: 1.0 Snellen (equivalent to ≥ 3/5 letter on the 1.0 line = 83 ETDRS letters) Exclusion Criteria: Manifest or latent squint. Contraindications to the use of OKL comprising keratoconus, chronic allergic conjunctivitis and keratoconjunctivitis sicca. Previous eye surgery. Chronic eye disease demanding daily use of eye drops. Non-compliance to eye examinations

Ages Eligible for Study
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Minimum Age: 6 Years
Maximum Age: 12 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: OKL<br> | Device: Orthokerathology lenses (OKL)<br>* 18 months of therapy.<br>* Other names: Night lenses;|
| Experimental: DIMS<br> | Device: Defocus Incorporated Multiple Segment (DIMS) Spectacles<br>* 18 months of therapy.<br>* Other names: Defocus (DIMS) Spectacles;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Axial length growth of the eye | Length is measured in mm | During 18 months of therapy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall eye length growth, defined as the sum of axial length and choroidal thickness | Length is measured in mm | During 18 months of therapy | 
| Pupil size | Length is measured in mm | During 6 months of therapy | 
| Choroidal thickness | Thickness is measured in um | During 18 months of therapy | 
| Vision related quality of life using the questionnaire PREP2 | Range from strongly disagree to strongly agree | Prior to and 9 months after treatment initiation |