Subfoveal Choroidal Thickness in Thai Population

Study Overview
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Brief Summary
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The purpose of this study was to determine the subfoveal choroidal thickness in normal Thai eyes and study the associations with gender, age, refractive error and axial length using spectral-domain optical coherence tomography with enhanced depth imaging technique.

Detailed Description
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Alteration of choroidal blood supply causes changes in choroidal thickness and results in choroidal abnormalities. These are usually associated with retinal diseases and leading to severe visual dysfunction. Choroidal thickness is therefore helpful in diagnosis and treatment for many chorioretinal conditions. With the advent of spectral domain optical coherence tomography and enhanced depth imaging technique, choroidal thickness has been investigated widely in normal eyes and various chorioretinal diseases including central serous chorioretinopathy (CSC), age-related macular degeneration (AMD), highly myopia and Vogt Koyanagi-Harada disease. Similar to retinal thickness, a normal baseline choroidal thickness might be used for interpretation. This value might be affected by several variables including age, gender and ethnicity. Although there were previous studies on subfoveal choroidal thickness in normal eyes from many countries, there has been no such study in Thailand. The purpose of this study was to determine the subfoveal choroidal thickness in normal Thai eyes and study the associations with gender, age, refractive error and axial length using SD-OCT and EDI technique.

Official Title
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Subfoveal Choroidal Thickness in Thai Population

Conditions
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Healthy

Intervention / Treatment
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* Other: measure subfoveal choroidal thickness


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18 years or above Healthy subjects No ocular diseases Written informed consent form Exclusion Criteria: patients with systemic diseases that may affect retinal or choroidal thickness including diabetes patients with history of refractive surgeries, intraocular surgeries or retinal laser treatments patients with history of macular, retinal, or optic nerve abnormalities

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 |
| --- | --- |
| Healthy volunteers<br>to measure the subfoveal choroidal thickness in healthy volunteers | Other: measure subfoveal choroidal thickness<br>* measure subfoveal choroidal thickness using optical coherence tomography<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| subfoveal choroidal thickness | Thickness of choroid at the foveal area | up to 4 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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subfoveal choroidal thickness, optical coherence tomography, enhanced depth imaging