Monocular Action Video Game Treatment of Amblyopia

Amblyopia is the condition in which there is a decrease in monocular visual acuity or, less frequently, binocular, in absence of structural anomalies or ocular pathology. It is a reversible condition that affects up to 5% of the population, and that is the result of an abnormal visual experience during the most sensitive period of visual development.

The aim of this study is reviewing, analyzing and, if applicable, updating the current treatment model for amblyopia.

A randomized clinical trial will be performed to evaluate the effectiveness of the monocular treatment with action video-games in comparison with the occlusion therapy alone in amblyopic patients, and the satisfaction with the different evaluated treatments. The participants will be distributed in two groups. The first group will include those participants who will follow a daily occlusive treatment and the second group will include patients who will be treated with monocular therapy with video-games.The sample will include subjects between 4 to 10 years old with a diagnosis of refractive and / or strabismic amblyopia.

• Monocular Active Occlusion (Other): Occlusion treatment of one hour daily with action video game.
• Monocular Passive Occlusion (Other): Occlusion treatment of two hour daily.

Primary outcomes

• Change from baseline visual acuity (VA) at 14 hours , 28 hours , and 42 hours comparing passive occlusion vs active occlusion (with action video games). [Baseline and 14, 28 and 42 hours post treatment.]: Visual Acuity (VA in logMAR) will be evaluated by E Snellen Test through an Ipad and the app AmblyopiaVA. The AmblyopiaVA test is designed based on the standard protocol for measuring Visual Acuity in children with Amblyopia.The measure will be performed at 2 m.
• Change from baseline stereopsis (ST) at 14 hours , 28 hours , and 42 hours comparing passive occlusion vs active occlusion (with action video games). [Baseline and 14, 28 and 42 hours post treatment.]: Stereopsis (ST in logMAR) will be evaluated by a Multiple Random Points test through an Ipad, the app StereoTAB and anaglyphic glasses. The measures will be performed at 50 cm.
• Change from baseline contrast sensitivity function (CSF) at 14 hours , 28 hours , and 42 hours comparing passive occlusion vs active occlusion (with action video games). [Baseline and 14, 28 and 42 hours post treatment.]: The effect of treatment on Contrast Sensitivity Function (CSF in logMAR) will be evaluated by ClinicCFS test using sine grids of four different spatial frequencies: 3, 6, 12 and 18 cpd.

Secondary outcomes

• Satisfaction assessed by an ordinal questionnaire designed based on the Treatment Satisfaction Questionnaire for Medication (TSQM). [42 hours]: Satisfaction assessed by an ordinal questionnaire (1 to 5, as 1 the lowest satisfaction and 5 the highest satisfaction),based on the TSQM (Treatment Satisfaction Questionnaire for Medication) version 1.4 to provide data regarding the degree of satisfaction and sensation of parents and children in relation to treatment.
• Rate of Compliance comparing passive occlusion vs active occlusion (with action video games) assessed by Google Analytics and written questionnaire. [Baseline and 14h, 28h and 42 hours.]: Rate of Compliance assessed through the registration of parent-reported adherence and log file data in Google Analytics (descriptive scale of time in hours/day) for active group and parent's questionnaire for passive group (subjective scale in hours/day)

Sex: All, ages: 4 Years to 10 Years

Inclusion Criteria:

* Age 4-10 years old
* Anisometropic amblyopia
* Strabismic amblyopia or mixed
* Interocular visual acuity (VA) difference of at least 0.2 logMAR
* No history of eye surgery

Exclusion Criteria:

* Non-comitant and/or large constant strabismus (>30 prism diopters)
* Any ocular pathological condition or nystagmus

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• Laura Asensio Jurado, MsC, Principal investigator, Universitat Politècnica de Catalunya
• Marc Argilés Sans, PhD, Study director, Universitat Politècnica de Catalunya
• Lluïsa Quevedo i Junyent, PhD, Study director, Universitat Politècnica de Catalunya