Shanghai High Myopia Study for Adults

Study Overview
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Brief Summary
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High myopia retinopathy has become the first cause of irreversible blindness and severe visual impairment in Chinese adults, in order to avoid the blind and visual impairment caused by high myopia retinopathy, it is very necessary to research the mechanism of early visual impairment to prevent and control damages. Our recent research found that the decreasing of macular retina vascular density and subfoveal choroidal thickness, the increasing of Beta Zone area in optic atrophy and the rising of glycosylated hemoglobin in high myopia patients were significantly related to visual impairment, which suggested that the source of visual impairment was the abnormal structure changes surrounding optic and fovea, but so far there is no related study. We will conduct a 5 years prospective cohort study in the population of 2420 high myopia and controls which have established in college student population, working population and aged more than 50 years old population, using the latest OCT-A and SS-OCT to measure macular retina vascular density, subfoveal choroidal thickness, Beta Zone area in optic atrophy, combined with the semiparametric mixed effects model, we will analysis the prediction index between fundus structure parameters, blood biochemical index and individual characteristics prediction to explore the public health management mode of early prevention and treatment during high myopia population.

Official Title
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The Cohort Study of Early Visual Impairment Mechanism Caused by Change of Fundus Structure in Adults With High Myopia

Conditions
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High Myopia

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ≥18 years old; spherical equivalent refraction ≤-6.00D; Exclusion Criteria: a history of ocular or systemic diseases including congenital cataract and glaucoma; previous intraocular or refractive surgery;other evidence of retinal pathology

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 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 |
| --- | --- |
| college student population<br> | |
| working population<br> | |
| aged more than 50 years old population<br> | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Retina Vessel Density (RVD) | RVD is calculated both the macular and peripapillary area. | December 31, 2016 | 
| tilted optic disc | A tilted optic disc was defined as the tilt ratios ≤0.80. | December 31, 2016 | 
| β-zone PPA | The β-zone PPA area (an inner crescent of chorioretinal atrophy with good visibility of the large choroidal vessels and the sclera) was determined as the total number of pixels using the ImageJ software in a circumferential pattern. | December 31, 2018 | 
| glycosylated hemoglobin | This test measures the average blood sugar control for the previous three months or so. | December 31, 2020 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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High Myopia, fundus structure, early visual impairment