Binocular Vision Alternations and fMRI Activation After ICL Implantation for High Myopia

Study Overview
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Brief Summary
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Implantable collamer lens (ICL) is one of the most effective operation for high myopia. Due to refractive correction changed, and prism effect of the spectacle removed, in the early stage after ICL implantation, binocular function might be dysfunction, leading to asthenopia, blurred vision, double vision and so on. This study will recruit the high myopia subjects that scheduled for ICL implantation, purpose to investigate the binocular vision alternations and brain activation that impacted by ICL implantation.

Official Title
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Binocular Vision Alternations and Functional Magnetic Resonance Imaging Activation After Implantable Collamer Lens Implantation for High Myopia

Conditions
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Binocular Vision Disorder

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18-35 Spherical equivalent over -6.00DS, astigmatism within -2.00DC, anisometropia within -2.00DS BCVA ≥ 0.8 Plan to accept implantable collamer lens surgery Near point of convergence within 10cm Positive fusion vergence over 20pd Exclusion Criteria: Stabismus Previous ocular surgery or trauma History of vision therapy Monovision and nystagmus Mental disease or craniocerebral trauma

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 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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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes of phoria at different time points | Phoria was measured by phoropter. | The examination was performed before operation and 1 week, 1 month, 3 monthes, 6 monthes after ICL implantation. | 
| Changes of AC/A at different time points | Gradient AC/A was measured by phoropter. | The examination was performed before operation and 1 week, 1 month, 3 monthes, 6 monthes after ICL implantation. | 
| Changes of fusion vergence at different time points | Fusion vergence was measured by phoropter. | The examination was performed before operation and 1 week, 1 month, 3 monthes, 6 monthes after ICL implantation. | 
| Changes of accommodative response at different time points | Accommodative response was measured using monocular estimated method. | The examination was performed before operation and 1 week, 1 month, 3 monthes, 6 monthes after ICL implantation. | 
| Changes of relative accommodation at different time points | Relative accommodation was measured by phoropter. | The examination was performed before operation and 1 week, 1 month, 3 monthes, 6 monthes after ICL implantation. | 
| Changes of near point of convergence at different time points | Near point of convergence was measured using push-up method. | The examination was performed before operation and 1 week, 1 month, 3 monthes, 6 monthes after ICL implantation. | 
| Changes of accommodation amplitude at different time points | Accommodative amplitude was measured using push-up method. | The examination was performed before operation and 1 week, 1 month, 3 monthes, 6 monthes after ICL implantation. | 
| Changes of vergence facility at different time points | Vergence facility was measured by +2.00D/-2.00D flipper. | The examination was performed before operation and 1 week, 1 month, 3 monthes, 6 monthes after ICL implantation. | 
| Changes of accommodative facility at different time points | Accommodative facility was measured by 3△BI/12△BO flipper. | The examination was performed before operation and 1 week, 1 month, 3 monthes, 6 monthes after ICL implantation. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes of brain activation at different time points | Functional magnetic resonance imaging activation of the brain | The examination was performed before operation and 1 month, 6 monthes after ICL implantation. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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binocular vision, accommodation, vergence, fMRI