Dichoptic Video Treatment for Amblyopia

Study Overview
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Brief Summary
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To determine whether watching contrast-rebalanced dichoptic videos is effective in improving visual acuity and reducing interocular suppression in amblyopic children To compare the amount of visual acuity improvement achieved with the videos to tha amount achieved with patching (standard treatment for amblyopia)

Detailed Description
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Contrast-rebalanced binocular iPad tablet games (with fellow eye contrast reduced) have been shown to be an effective treatment for amblyopia. However, the games can be challenging for some of the youngest children and boring for some of the older children with amblyopia. To provide additional treatment options using the same contrast-rebalancing approach, we have processed animated videos to allow dichoptic viewing, with full contrast for the amblyopic eye and reduced contrast for the fellow eye. Children will be randomly assigned to watch dichoptic videos (experimental treatment) or patch 2 hours/day every day(standard-of-care amblyopia treatment) for 2 weeks. At the 2-week primary outcome visit, children in the patching group will cross over to the videos and return for a secondary outcome visit at 4 weeks. Families will have the option to continue with the vdeos for up to 8 weeks.

Official Title
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Dichoptic Video Treatment for Amblyopia in Children Age 3-7 Years

Conditions
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Amblyopia

Intervention / Treatment
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* Other: patching
* Other: Dichoptic videos


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 3 to 7 years old Amblyopic eye visual acuity 20/32-20/125 Fellow eye visual acuity 20/16-25 Interocular visual acuity difference of at least 2 lines Anisometropia or corrected strabsimus (<5pd) in glasses at least 8 weeks or no change in visual acuity over two visits no prior binocular treatment must be able to see full video screen Exclusion Criteria: prematurity of 8 weeks or more coexisting ocular or systemic disease developmental delay poor ocular alignment (>=5 pd)

Ages Eligible for Study
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Minimum Age: 3 Years
Maximum Age: 7 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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Parallel for primary outcome; crossover for longterm effectiveness
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Patching<br>2 hours per day 7 days per week patching of the fellow eye | Other: patching<br>* covering the fellow eye with an eyepatch to force use of the amblyopic eye<br>* Other names: occlusion therapy;|
| Experimental: Dichoptic Videos<br>watching 6 dichoptic videos during each 2 week period | Other: Dichoptic videos<br>* watching contrast-rebalanced dichoptic videos to allow the two eyes to work together<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in visual acuity of the amblyopic eye | HOTV (preferred) or picture chart | Baseline vs 2 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in visual acuity of the amblyopic eye | HOTV (preferred) or picture charts | Baseline vs 4 weeks, 6 weeks, and 8 weeks | 
| Change in Stereoacuity | Randot Preschool Stereoacuity test | Baseline vs 2, 4, 6, 8 weeks | 
| Change in Contrast Balance Index | Dichoptic Letter chart | Baseline vs 2, 4, 6, 8 weeks |