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