Effects on Ocular Parameters of Myopic Eyes After Orthokeratology in Myopic Children

Study Overview
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Brief Summary
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Effects on Ocular Parameters of Myopic Eyes After Orthokeratology in Myopic Children

Detailed Description
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1.The primary objective of the current study is to investigate changes in uncorrected visual acuity, diopter, accommodation, peripheral refraction, IOP, tear film quality, corneal thickness, corneal topography, corneal biomechanical parameters, objective optical quality, corneal and conjunctiva sensitivity and choroidal thickness for children with different diopters after wearing orthokeratology lenses; 2. Through measure long-term changes of these parameters, including corneal topography, axial length, peripheral refraction, objective optical quality and choroidal thickness, to explore occurrence and development regularity of myopia.

Official Title
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Effects on Ocular Parameters of Myopic Eyes After Orthokeratology in Myopic

Conditions
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Myopia

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1. subjects were 6-16 years of age; 2.had no other ocular diseases aside from refractive error and no keratoconus (confirmed by pre-treatment corneal topography); 3. had an intraocular pressure (IOP) of <21 mmHg; 4. had an with-the- rule astigmatism (axes 180 ± 30) ≤ 1.50 D; 5.had a best corrected visual acuity（BCVA） ≤0.00 log MAR units in both eyes (Snellen equivalent to 20/20); Exclusion Criteria: 1. had binocular vision problems; 2.use medications that might affect refractive development; 3.had history of ortho-k or contact lens wear; 4. Ocular surface diseases and other eye diseases which can cause abnormalities of ocular surface; 5. Patients with histories of ocular injury or surgery; 6. Corneal staining and decentration of lens after wearing Ortho-k.

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| low myopia<br>-3.00D < spherical equivalent refractive error < -0.50D | |
| moderate myopia<br>-6.00D < spherical equivalent refractive error ≤ -3.0D | |
| high myopia<br>spherical equivalent refractive error ≤ -6.0D | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| axial length measured by IOL-master | measured by IOL-master | 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| accommodation measured by open field auto ref/keratometer measurements(WAM-5500,Grand Seiko) | measured by open field auto ref/keratometer measurements(WAM-5500,Grand Seiko) | 2 years | 
| peripheral refraction measured by open field auto ref/keratometer measurements(WAM-5500,Grand Seiko) | measured by open field auto ref/keratometer measurements(WAM-5500,Grand Seiko) | 2 years | 
| IOP measured by Corvis-ST | measured by Corvis-ST | 2 years | 
| corneal thickness measured by Corvis-ST | measured by Corvis-ST | 2 years | 
| corneal biomechanical parameters measured by Corvis-ST | measured by Corvis-ST | 2 years | 
| tear film quality measured by Keratography | measured by Keratography | 2 years | 
| corneal morphological characteristics measured by Optikon 2000 corneal topographer | measured by Optikon 2000 corneal topographer | 2 years | 
| objective optical quality measured by OQAS visual quality analyzing system | measured by OQAS visual quality analyzing system | 2 years | 
| corneal and conjunctiva sensitivity measured by Cochet-Bonnet | measured by Cochet-Bonnet | 2 years | 
| choroidal thickness measured by ocular coherence tomography | measured by ocular coherence tomography | 2 years |