Interest in developing alternative methods for the treatment of amblyopia (lazy eye) has long been a topic of interest among clinicians and researchers. Occlusion or penalization of fellow eye do not always provide the desired visual acuity improvement. Moreover, occlusion is associated with a high risk of recurrence and non-compliance. Here, it is presented a protocol of a randomized clinical trial to evaluate the safety and clinical efficacy of a novel home-based system, based on a computer game.

The goal of this prospective clinical trial is to compare in visual acuity improvements in patients with amblyopia, following conventional patching therapy or this novel computer-based therapy.

The main questions it aims to answer are:

• Does computer-based therapy equal or improve patching therapy? Can it be used as an alternative to patching?
• Does computer-based therapy used in combination with pathching solve amblyopia when patching fails alone (persistent amblyopia)?

Participants will be divided in two groups according to the previous occlusion o penalization of fellow eye. Both groups will be divided in two subgroups, experimental and control. Researchers will compare subgroups outcomes in order to asses this novel approach.

Amblyopia is a common neurodevelopmental abnormality that results in physiological alterations of the visual pathways and impaired vision in one eye or, less commonly, in both.Disruption of normal visual development early in life may result in perceptual, oculomotor and clinical abnormalities such as instability of fixation, anomalous retinal correspondence, and lack of stereoacuity.Amblyopia has a prevalence of around 2-4% in children and is associated with refractive error (anisometropia or isometropia) and strabismus.

The Pediatric Eye Disease Investigator Group (PEDIG) has produced several studies that analyze the most effective therapies for amblyopic eye. The gold standard treatment prescribed for this condition combines spectacle correction of the refractive error with penalization and/or occlusion of the dominant eye

Interest in developing alternative methods for the treatment of amblyopia (lazy eye) has long been a topic of interest among clinicians and researchers. Occlusion or penalization of fellow eye do not always provide the desired visual acuity improvement. Moreover, occlusion is associated with a high risk of recurrence and non-compliance.

This randomized clinical trial is designed to evaluate the safety and clinical efficacy of a novel home-based system, based on a computer activity that uses dichoptic Gabor Patches and band-filtered noise masks. It combines the concepts of perceptual learning, dichoptic training, home based therapy and gamification.

The goal of this prospective clinical trial is to compare in visual acuity improvements in patients with amblyopia, following conventional patching therapy or this novel computer-based therapy.

The main questions it aims to answer are:

• Does computer-based therapy equal or improve patching therapy? Can it be used as an alternative to patching?
• Does computer-based therapy used as coadjuvant to pathching solve amblyopia in patients where patching fails alone (persistent amblyopia)?

Participants will be divided in two groups according to the previous occlusion o penalization of fellow eye. Both groups will be divided in two subgroups, experimental and control. Researchers will compare subgroups outcomes in order to asses if this novel approach may lead to greater improvements in vision performance in amblyopic children as substitution of occlusion treatment in novel amblyopia or as coadjutant in persistent amblyopia.

Inclusion Criteria:

• The sample will be made up of children with amblyopia from 4 to 12 years old (amblyopia will be defined as the best corrected visual acuity less o equal to 0.8 in decimal units or > 2 lines of difference between both eyes). Strabismus inclusion criteria will be < 25 prismatic diopters, with a deviation ≥ 2 prismatic diopters.

Exclusion Criteria:

• Subjects with nystagmus, ocular pathology o cognitive delay will be excluded.

Ophthalmologists at the Pediatric Ophthalmologic Unit (Care Provider and Outcomes Assessor) will decide if volunteers meet inclusion criteria. They will assign the patient to GA or GB. They will be responsible for final and after treatment visual evaluations.

The Quality Service of the Merida Hospital (Investigator) will randomize GA and GB volunteers into treatment or control subgroups. This service will be responsible for the custody of documentation and the statistical final analysis.

Visionary team (Investigator) will communicate the patient about the treatment (occlusion or Visionary software, or both).

Optometrists at the Pediatric Ophthalmologic Unit (Outcomes Assessor) will oversee BCVA and stereoacuity measurements during treatment.