Binocular Amblyopia Treatment

Study Overview
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Brief Summary
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To evaluate the effectiveness of enhanced binocular amblyopia treatments in achieving a more complete and stable recovery.

Detailed Description
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To date, all studies of contrast-rebalanced binocular amblyopia treatment games used the same 10% per day contrast-increment that was designed for short-term intervention studies lasting 1-4 weeks; i.e., after 18 days of successful game play, both eyes viewed 100% contrast (no contrast-rebalancing).This study will investigate two alternative protocols designed to extend the game treatment period beyond 4 weeks to allow for more complete recovery of visual acuity. The new protocols will be compared with the original 10% contrast-increment game protocol in an 8-week 3-arm RCT to determine whether one or both of the new protocols is more effective than the current 10% increment. Based on pilot data, we expect about 40% of amblyopic children to achieve normal visual acuity in 8 weeks. In an effort to also promote recovery of binocular vision, children who attain ≤0.4 logMAR at 8 weeks will be enrolled in stereoacuity training at the 8-week visit for the next 4 weeks. Children with residual amblyopia (BCVA >0.4 logMAR) at the 8-week visit will be provided with dichoptic movies for additional amblyopia treatment for another 4 weeks.

Official Title
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Binocular Amblyopia Treatment

Conditions
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Amblyopia

Intervention / Treatment
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* Other: Binocular games for treatment of amblyopia


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age 4-10 y male and female strabismic, anisometropic, or combined mechanism amblyopia amblyopic eye best-corrected visual acuity 0.3-0.8 logMAR fellow eye best-corrected visual acuity ≤0.1 logMAR interocular visual acuity difference ≥0.3 logMAR wearing glasses (if needed) for 8 weeks or no change visual acuity with glasses at 2 visits 4 weeks apart. child's ophthalmologist and family must be willing to forgo patching treatment during the 12-week study period parent's informed consent child must demonstrate understanding and ability to play binocular games Exclusion Criteria: prematurity ≥8 weeks coexisting ocular or systemic disease developmental delay strabismus >5pd any binocular amblyopia treatment in the past 3 months

Ages Eligible for Study
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Minimum Age: 4 Years
Maximum Age: 10 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
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Standard Contrast Increment<br> | Other: Binocular games for treatment of amblyopia<br>* playing binocular games on a tablet platform 1 hour per day 5 days per week with reduced contrast for the fellow eye and high contrast for the amblyopic eye<br>|
| Experimental: Reduced Contrast Increment<br> | Other: Binocular games for treatment of amblyopia<br>* playing binocular games on a tablet platform 1 hour per day 5 days per week with reduced contrast for the fellow eye and high contrast for the amblyopic eye<br>|
| Experimental: No Contrast Increment<br> | Other: Binocular games for treatment of amblyopia<br>* playing binocular games on a tablet platform 1 hour per day 5 days per week with reduced contrast for the fellow eye and high contrast for the amblyopic eye<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 | ATS-HOTV for age 4-6.9 years or E-ETDRS for age 7-10.9 years | baseline vs 8 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in visual acuity of the amblyopic eye | ATS-HOTV for age 4-6.9 years or E-ETDRS for age 7-10.9 years | baseline vs 2, 4, 6, and 12 weeks | 
| Change in stereoacuity | Randot Preschool Stereoacuity Test | baseline vs 2, 4, 6, 8, 12 weeks | 
| Change in suppression | Dichoptic Letter Chart | baseline vs 2, 4, 6, 8, 12 weeks |