Assessment of Corneal Biomechanics With the Corvis ST in Different Age of Myopia With Orthokeratology

Study Overview
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Brief Summary
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The present research focused on the effect of the age for the corneal biomechanics of low and moderate myopia patients after wearing orthokeratology (OK lens). According to age, the included cases were divided into 3 groups. Through the analysis of corneal biomechanical parameters, further learn the influence of OK lens on the patient cornea. It would help ophthalmologist and optometrist find out the potential issue and reach a better control result.

Detailed Description
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The present research focused on the effect of the age for the corneal biomechanics of low and moderate myopia patients after wearing orthokeratology (OK lens). According to age, the included cases were divided into 3 groups: Ⅰ (8-12 years old), Ⅱ (13-16 years old), Ⅲ (over 16 years old). The OK lenses used in the present study are of the same design (Euclid Systems Orthokeratology; Euclid System, Herndon, VA, USA). The base line (Day 0) and different follow-up time point (Day 1, Week 1, Week 2, Month 1, Month 3, and Month 6) of dynamic corneal response (DCR) (including 19 items) of the patients derived by Corvis ST were collected. The difference between before and after wearing OK Lens and the changes of parameters among the three groups were both analyzed. And the correlation between axis length (AL) and the 19 parameters also was analyzed. Through the analysis of corneal biomechanical parameters, further learn the influence of OK lens on the patient cornea. It would help ophthalmologist and optometrist find out the potential issue and reach a better control result.

Official Title
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Assessment of Corneal Biomechanics With the Corvis ST in Different Age of Myopia With Orthokeratology

Conditions
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Myopia, Orthokeratology

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age from 8 to 40 years old spherical equivalent(SE) was range from -1.00D to -5.00D conform to the standard of wearing orthokeratology lens Exclusion Criteria: ocular diseases and systemic diseases visual acuity was less than 20/20 unable to follow visitors on time

Ages Eligible for Study
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Minimum Age: 8 Years
Maximum Age: 40 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 1<br>8-12 years old | |
| 2<br>13-16 years old | |
| 3<br>over 16 years old | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The change of dynamic corneal response (DCR) | The axial length was measured by Corvis ST | The change of baseline and 1 day, 1 week, 2 weeks, 1 month, 3 months, and 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The change of axial length | The axial length was measured by AL-scan | The change of baseline and 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Myopia prevention and control, Orthokeratology, Dynamic corneal response