Patching or Gaming as Amblyopia Treatment?

Study Overview
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Brief Summary
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Amblyopia affects 3% of the children and is caused by strabismus, anisometropia or both. Standard treatment is glasses and patching therapy. From North-America, behavioural training, i.e. dichoptic training, perceptual learning and video gaming, has become increasingly popular to improve visual acuity not only in children but also in adults. In this study we aim to compare the standard occlusion therapy with dichoptic video gaming.

Detailed Description
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Amblyopia affects 3% of the children and is caused by strabismus, anisometropia or both. The standard treatment is glasses and patching therapy. From North-America, behavioural training, i.e. dichoptic training, perceptual learning and video gaming, has become increasingly popular. The rationale behind these games is by using dichoptic stimulation, with the contrast of the stimuli presented to the good eye reduced to match the appearance of the same stimuli when shown to the amblyopic eye, suppression can be alleviated. The many studies now conducted, demonstrate improvement in visual acuity with the games, the effect however is limited, but the rate of improvement is higher. In these studies, prescribed patching-time was compared to realised game-time. We have demonstrated in multiple studies that electronically measured compliance is low: on average only 50%. In this study we aim to compare the effect of patching therapy, using the ODM to objectively measure compliance, with the effect of a novel dichoptic action video game in children as well as in adults. In addition, the adult participants will undergo fMRI scans to document any changes in the visual cortex before and after either therapy.

Official Title
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A Randomised Clinical Trial Objectively Comparing the Effect of Patching Therapy With Video Gaming for Amblyopia

Conditions
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Amblyopia

Intervention / Treatment
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* Other: Dichoptic video game therapy
* Other: Occlusion therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Amblyopia; an interocular difference in visual acuity of at least 2 logMAR lines. Exclusion Criteria: A non-comitant or large angle constant strabismus >30Prism Dioptres, a neurological disorder, nystagmus, other eye disorders and diminished acuity due to medication, brain damage or trauma.

Ages Eligible for Study
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Minimum Age: 4 Years
Maximum Age: 55 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: Participants are randomized to either the standard patching therapy or the dichoptic video game therapy.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Occlusion therapy<br>Participants are prescribed 2 hours of occlusion therapy per day, 7 days a week. | Other: Occlusion therapy<br>* Occlusion therapy for 2 hours per day, 7 days a week<br>|
| Experimental: Dichoptic video game therapy<br>Participants receive dichoptic video game therapy: 1 hour per week at the out-patient clinic under direct supervision. | Other: Dichoptic video game therapy<br>* Dichoptic video gaming for 1 hour per week, viewed through the Oculus Rift.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual Acuity improvement | Visual Acuity improvement (logMAR units/time period) in children with amblyopia treated with patching therapy vs dichoptic video gaming | 24 weeks |