Development and Validation of a Novel Stereoacuity Test Using Head-mounted Display

Study Overview
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Brief Summary
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This prospective study investigated the validity and test-retest reliability of stereopsis test using head-mount display (HMD). Contour-based circles (crossed disparity: 1,960 to 195 arc of seconds(arc secs)) were generated as separate images on a high resolution phone display (Galaxy S7; Samsung, Suwon, Korea) using a HMD (Galaxy Gear VR; Samsung, Suwon, Korea). Two images were independently projected to each eye as graded circles with random dot background. While the position of the stimulus changed from among 3 possible locations, the subjects were instructed to select the circle with disparity by pressing the corresponding position on a keypad. The results of the new HMD stereotest were compared to those from standard Randot and TNO stereotests.

Official Title
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Development and Validation of a Novel Stereoacuity Test Using Head-mounted Display

Conditions
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Normal Healthy Volunteers

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1. The subjects who want or need to visual acuity test or to test for a prescription for glasses visited the hospital. 2. The Subjects' ages ranged from 19 to 60 years in the study. Exclusion Criteria: Ocular alignment was assessed with cover-uncover and alternate prism cover testing at distance and near. Significant exodeviation included exophoria was considered to be ≥6 prism diopters were excluded. Subjects with a history of ocular surgery within 3 months of the study were excluded. Foreigners or subjects who are unable to understand informed consent were excluded. Subjects with a history of eye problems, including infection, inflammation, cataract, vitreous opacity or retinal diseases were excluded. Subjects with corrected visual acuity of 20/32 in bad eye were excluded. Subjects with significant refractive error considered to be ≥2.00 diopters of anisometropia were excluded. A female who is pregnant, may be pregnant, or is lactating was excluded.

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 60 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Normal healthy volunteers<br> | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between stereopsis with head mount display and stereopsis with Randot or TNO test | Stereopsis results was expressed as arc sec. The association between log arc sec in stereopsis with HMD display and Randot or TNO test were evaluated. Using Bland Altman plot, the mean differences between two stereopsis results were compared. | one visit | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Test-retest variability of stereopsis using head mount display | The intraclass coefficient was calculated between initial head mount display stereopsis result and retests. | one visit |