Improving Control of Intermittent Exotropia

Intermittent exotropia (IXT) is the most common form of strabismus, characterized by an outward deviation of the eyes that is primarily manifest during distance fixation and can intermittently be controlled by fusional mechanisms. Less than 30% of children have good long-term outcomes following treatment for spontaneously manifest IXT with current non-surgical treatments (prism therapy, over-minus lenses, or vision therapy). The limited efficacy of current non-surgical treatments for IXT is thought to arise from underlying sensory deficits, particularly interocular suppression, which compromises binocular function. This underscores the need for sensory-directed interventions aimed at reducing suppression and thereby enhancing the potential for stable binocular outcomes.

In this study, children will be randomized to watch engaging videos streamed at home that are either dichoptic or standard (control) format. The aim is to determine whether the dichoptic format will decrease suppression and improve control of eye alignment . In previous research, use of dichoptic games and movies by children with amblyopia has shown to reduce suppression.

Inclusion criteria

• Diagnosis of IXT or XT at Distance & IXT or XP at near (Basic or Pseudo Divergence Excess subtype of IXT)
• No surgery planned for 6 months

Exclusion criteria

• Prior eye muscle surgery
• Prior binocular treatment or vision therapy
• Amblyopia
• Neurological conditions, seizure disorders, vestibular abnormalities, or frequent headache
• Other eye conditions (refractive error OK)