Choroidal Thickness Change in Response to Physiological and Refractive Changes

Study Overview
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Brief Summary
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There is a great need for precise and repeatable measurements of the choroidal thickness. Including the diurnal physiological changes, accommodation and refractive error impact on those measurements.

Official Title
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Automatic Measurements of Choroidal Thickness Change in Response to Physiological and Refractive Changes

Conditions
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Refractive Errors, Accommodation Disorder

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: participants with refractive error willing and able to understand and sign an informed consent form Exclusion Criteria: patient unable to participate in the study any disease that causes visual opacity of optic media that unable to perform OCT scanning current enrolment in another clinical trial/research project

Ages Eligible for Study
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Minimum Age: 18 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 |
| --- | --- |
| Myopic participants<br> | |
| Emmetropic participants<br> | |
| Hyperopic participants<br> | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Submacular choroidal thickness | OCT EDI recorded scans will be proceed with the custom-made software to determine choroidal thickness in the submacular region. | 1 day | 
| Peripapillar choroidal thickness | OCT EDI recorded scans will be proceed with the custom-made software to determine choroidal thickness in the peripapillar region. | 1 day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Axial length of the globe | Measured with optical biometer (Lenstar) | 1 day | 
| Anterior chamber depth - optical biometry | Measured with optical biometer (Lenstar) | 1 day | 
| Phakic lens thickness | Measured with optical biometer (Lenstar) | 1 day | 
| White to white diameter | Measured with optical biometer (Lenstar) | 1 day | 
| Angle to angle diameter of anterior chamber | Measured with optical coherent tomography for anterior chamber | 1 day | 
| Anterior chamber depth - OCT | Measured with optical coherent tomography for anterior chamber | 1 day | 
| Corneal keratometry (steep meridian and its axis and flat meridian with its axis) | Keratometry from autorefractokeratometer, topography or tomography recordings, radius measured in mm, magnitude of corneal astigmatism measured in local changes of dioptric power. | 1 day | 
| Spherical ametropia with cylindrical power of correcting lenses | Subjective refraction made by trained optometrist. Spherical ametropia measured by dioptric power of spherical equivalent lens and magnitude of astigmatism measured in cylindrical dioptries of correcting lens with its axis. Mode of notation: sphero-cylinder with negative cylinder (e.g. +0.50DS -0.50DC 180ax) | 1 day | 
| Best-corrected visual acuity | examined on ETDRS charts different for right and left eye | 1 day |