Binocular Amblyopia Treatment

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.

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