Comparison of Objective and Subjective Changes Induced by Multiple Pinhole Glasses and Single Pinhole Glasses

Study Overview
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Brief Summary
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Purpose of this study is to compare the ocular functional changes including pupil size, visual acuity, depth of focus, accommodative amplitude, visual field, contrast sensitivity, and stereopsis induced by multiple and single pinhole glasses, in addition, to check reading speed and survey for ocular discomfort after using both pinhole glasses.

Conditions
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Functional Vision Changes

Intervention / Treatment
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* Device: Trayner Pinhole Glasses (Trayner Glasses, Ivybridge Devon, U.K.)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age between 20 and 45 years; spherical equivalents (SE) within ± 6.0 diopters (D); correctable distant and near visual acuity by glasses up to 20/20; normal intraocular pressure with normal optic disc appearance; normal ocular alignment. Exclusion Criteria: disturbance of accommodation due to any reasons such as an Adie's pupil, Parkinson's disease, a history of previous ocular surgery or trauma, and a history of systemic or topical medication that might affect accommodation; corneal pathologic features; glaucoma; cataracts of grade II or greater by the Lens Opacities Classification System III (LOCS III); vitreous and retinal abnormalities that might limit the accuracy of testing.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 45 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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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Participants<br>All participants perform all exams under 3 conditions, that is baseline, single pinhole glasses, and multiple pinhole glasses | Device: Trayner Pinhole Glasses (Trayner Glasses, Ivybridge Devon, U.K.)<br>* Wearing multiple and single pinhole glasses<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Distant visual acuity (logMAR) | Distant visual acuity were measured using Snellen chart (Precision Vision, La Salle, IL, USA) at 4 m. | Subjects performed this examination while wearing multiple and single pinhole glasses with one week apart in random order after baseline study. | 
| Photopic pupil size (baseline, mm) | Pupil size under photopic conditions (85 cd/m2) was measured using a WASCA Analyzer (Carl Zeiss Meditec, Oberkochen, Germany). | Subjects performed this examination while wearing multiple and single pinhole glasses with one week apart in random order after baseline study. | 
| Depth of focus | Monocular DOF was checked with a 4-m Snellen chart under distance correction without cycloplegics. | Subjects performed this examination while wearing multiple and single pinhole glasses with one week apart in random order after baseline study. | 
| Accommodative amplitude (Diopter) | Near point of accommodation (NPA) was measured using Donder's push-up method. | Subjects performed this examination while wearing multiple and single pinhole glasses with one week apart in random order after baseline study. | 
| Standard automated perimetry | Visual field (VF) test was performed with a Humphrey Visual Field Analyzer (Carl Zeiss Meditec, Inc., Dublin, CA, USA) using the 30-2 Swedish interactive threshold algorithm. | Subjects performed this examination while wearing multiple and single pinhole glasses with one week apart in random order after baseline study. | 
| Contrast sensitivity | Monocular contrast sensitivity test was performed using a CSV-1000E Contrast Testing Instrument (VectorVision, Dayton, OH, USA) at 2.5-m distance under standard brightness (85 cd/m2) | Subjects performed this examination while wearing multiple and single pinhole glasses with one week apart in random order after baseline study. | 
| Stereopsis (seconds of arc) | Stereopsis was checked with the Randot Stereotest (Stereo Optical Co., Chicago, IL, USA). | Subjects performed this examination while wearing multiple and single pinhole glasses with one week apart in random order after baseline study. | 
| Reading speed (letters per second) | Reading speed was evaluated using the famous Korean traditional fairy tale book. This Korean book was printed black-and-white with 10-font size. The time taken to read designated 10 pages including 3985 letters was recorded, and then reading speed was calculated as letters per second (LPS). | Subjects performed this examination while wearing multiple and single pinhole glasses with one week apart in random order after baseline study. | 
| Near visual acuity (logMAR) | Near visual acuity using Logarithmic Visual Acuity Chart 2000 (Precision Vision, La Salle, IL, USA) at 40 cm. | Subjects performed this examination while wearing multiple and single pinhole glasses with one week apart in random order after baseline study. | 
| Pupil size with the both pinhole glasses (mm) | Pupil size with the both pinhole glasses using the ruler attached to the lateral rim of the glasses. | Subjects performed this examination while wearing multiple and single pinhole glasses with one week apart in random order after baseline study. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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young healthy adults, single pinhole glasses, multiple pinhole glasses