Low Concentration Atropine in the Prevention of Myopia in Children.

Study Overview
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Brief Summary
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This double-blind, randomized controlled clinical study is to evaluate the effectiveness and safety of low concentration atropine in preventing myopia in pre-myopia children, and to explore whether there is a dose effect relationship between different concentrations of atropine in preventing myopia.

Detailed Description
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The main questions this double-blind, randomized controlled clinical study aims to answer are: To evaluate the effect of low concentration atropine on the incidence of myopia in pre myopia children. To evaluate the effectiveness of low concentration atropine in controlling refractive and axial progression. Patients are randomly divided into three treatment groups with different atropine concentrations(0.01%, 0.02%, 0.04%) and one control group with atropine dissolvant. Patients are required to use the eye drops every night for one year and record after daily usage.

Official Title
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A Double-blind, Randomized Controlled Study of Low Concentration Atropine in the Prevention of Myopia in Pre-myopia Children.

Conditions
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Myopia, Progressive

Intervention / Treatment
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* Drug: low concentration atropine (0.01%)
* Drug: low concentration atropine (0.02%)
* Drug: low concentration atropine (0.04%)
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The age of the screening stage is 6-9 years, both sexes; One eye met the diagnosis of pre-myopia, the spherical equivalent was between -0.50D and +0.75D, the astigmatism was ≥-1.50D, and the best corrected far vision was at least 1.0; At least one of parents suffers from myopia (SE of at least one eye <=-3.00D); Parents have signed informed consent and agree to participate in screening and follow-up. Exclusion Criteria: Parents disagree to sign the informed consent; Presence of strabismus, amblyopia, or other ocular abnormalities, or have a history of eye surgery; Presence of other eye or systemic diseases; Allergies to low concentration atropine or sulfuric acid drugs; Histories of using other preventive measures, such as using red light within 6 months or atropine within 1 month; Presence of other situations that the researchers think is not appropriate for patients to be included in the project.

Ages Eligible for Study
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Minimum Age: 6 Years
Maximum Age: 9 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: 0.01% atropine<br>0.01% atropine eye drop | Drug: low concentration atropine (0.01%)<br>* low concentration atropine (0.01%)<br>|
| Experimental: 0.02% atropine<br>0.02% atropine eye drop | Drug: low concentration atropine (0.02%)<br>* low concentration atropine (0.02%)<br>|
| Experimental: 0.04% atropine<br>0.04% atropine eye drop | Drug: low concentration atropine (0.04%)<br>* low concentration atropine (0.04%)<br>|
| Placebo Comparator: placebo<br>placebo eye drop | Drug: Placebo<br>* Placebo eye drop<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cumulative Incidence of Myopia | Effectiveness Evaluation | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in SE (after cycloplegia) | Effectiveness Evaluation | 1 year | 
| Changes in AL | Effectiveness Evaluation | 1 year | 
| Changes in visual acuity | Effectiveness Evaluation | 1 year | 
| Changes in Choroidal Thickness | Effectiveness Evaluation | 1 year |