Myopia-control Efficacy by Peripheral Defocus Lens (PDL)

Study Overview
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Brief Summary
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The proposed study below aims to assess the effect of customized Bestivue PDL lenses on retinal image quality and myopia control. A total of 160 subjected would be enrolled in and randomized to allcoate into four groups. Visual acuity and image blur at various gaze directions and eccentricities on children fitted with +2 to 4 D power and single vision lenses would be measured to assess the short term effect of PDL lens. Axial length and cycloplegic objective refractive error would be measured to assess the Myopia-control Efficacy.

Detailed Description
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The proposed study below aims to assess the short-term and long-term effect of customized Bestivue PDL lenses on retinal image quality and myopia control. To these ends, two stages of testing are planned. First, objective testing will be utilized to assess the effect of Bestivue PDL lenses on visual acuity and image blur at various gaze directions and eccentricities on 4- to 13-year-old children fitted with +2 to 4 D power and single vision lenses.In the second stage, the same children participants will wear either single or Bestvue PDL lenses with one of the four plus power designs for 2 years. Their corrected visual acuity, objective refractive error with dilation and axial length will be assessed for each eye every six months for two years. Outcomes of these studies should inform whether Bestivue PDL lenses are effective in myopia control while affording adequate visual comfort and performance.

Official Title
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Evaluation of Visual Performance and Myopia-control Efficacy Afforded by Bestivue Peripheral Defocus Lens (PDL)

Conditions
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Myopia, Progressive

Intervention / Treatment
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* Device: Single vision lens
* Device: +2D PDL
* Device: +3D PDL
* Device: +4D PDL


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The subjects had spherical RE of -1.00 to -6.00 D Astigmatism ≤ 4.00 D Anisometropia ≤ 1.50 D\ Best corrected visual acuity (BCVA) equal to or better than logMAR 0.0 (20/20) in both eyes. Exclusion Criteria: Strabismus Ocular limitations Systemic abnormalities affecting vision and ocular motility.

Ages Eligible for Study
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Minimum Age: 6 Years
Maximum Age: 15 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Control group<br>The subjects are randomized to wear SV lens | Device: Single vision lens<br>* Wear single vision lens<br>|
| Experimental: experimental group +2D<br>The subjects are randomized to wear special designed lens with +2D Peripheral Defocus. | Device: +2D PDL<br>* Wear Peripheral defocus lense with +2D<br>|
| Experimental: experimental group +3D<br>The subjects are randomized to wear special designed lens with +3D Peripheral Defocus. | Device: +3D PDL<br>* Wear Peripheral defocus lense with +3D<br>|
| Experimental: experimental group +4D<br>The subjects are randomized to wear special designed lens with +4D Peripheral Defocus. | Device: +4D PDL<br>* Wear Peripheral defocus lense with +4D<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| changes in cycloplegic objective spherical equivalent (SER) | changes in cycloplegic objective spherical equivalent (SER) from baseline between four groups. | baseline, 24 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| changes in ocular axial length | Changes in ocular axial length from baseline between four groups. | baseline, 24 months | 
| visual performance | The visual acuity of peripheral between four groups. | 1 day |