A pilot randomized trial of contrast-rebalanced binocular treatment for deprivation amblyopia

Abstract

Background: Binocular neural architecture may be preserved in children with deprivation amblyopia due to unilateral cataract. The purpose of this study was to investigate whether a contrast-rebalanced binocular treatment, recently used with success to treat the interocular suppression and amblyopia in strabismic and anisometropic children, can contribute to rehabilitation of visual acuity in children with deprivation amblyopia secondary to monocular cataract.

Methods: In a pilot randomized trial, 15 children (4-13 years of age) were enrolled and randomized to continue with their current treatment only (n = 7) or to continue with their current treatment and add contrast-rebalanced binocular iPad game play 5 hours/week for 4 weeks (n = 8). The primary outcome was change in visual acuity at 4 weeks.

Results: Although 10 of 15 participants were patching, there was little change in visual acuity during the 3 months prior to enrollment. At the 4-week primary outcome visit, the mean improvement in visual acuity for the binocular game group was significantly greater than that for the current-treatment group (0.08 ± 0.10 logMAR vs -0.03 ± 0.05 logMAR [t_10.2 = 2.53, P = 0.03]). None of the children who had dense congenital cataract achieved improved visual acuity with binocular treatment.

Conclusions: In this study cohort, visual acuity improved over 8 weeks in children with unilateral deprivation amblyopia who played a binocular contrast-rebalanced binocular iPad game.

Trial registration: ClinicalTrials.gov NCT02365090.

FIG 1.

Change in best-corrected visual acuity of the treated eye relative to baseline visual acuity. The visits at −1 month and −3 months were visual acuities extracted from medical records for timepoints prior to enrollment. Visual acuity of children assigned to play contrast-rebalanced binocular games in addition to their current treatment improved relative to baseline at 4 weeks (P = 0.04) and at 8 weeks (P = 0.01). At the 4-week primary outcome visit, visual acuity of children in the contrast-rebalanced game group improved significantly more that visual acuity of children in the current-treatment group (P = 0.03).

FIG 2.

Number of logMAR lines improved for each group at the 4 and 8 weeks.