Abstract
Purpose :
Binocular treatment of childhood amblyopia rebalances contrast between the eyes, allowing the child to overcome suppression, experience binocular vision, and recover visual acuity (Birch et al., 2015; Li et al., 2014). For the first time, we evaluate baseline factors that may affect the success of binocular treatment for amblyopia.
Methods :
Amblyopic children (3-12y) with hyperopic anisometropia (HA; n=11, 20/40-20/400) myopic anisometropia (MA; n=6, 20/40-20/800) and hyperopic anisometropia + corrected esotropia (HA+ET; n=11, 20/40-20/125) were enrolled. Children chose from 18 popular animated feature films to watch contrast-rebalanced dichoptic versions during a 2-week period (total treatment time ~ 9hrs). Inclusion criteria: ≥8 weeks spectacle wear prior to baseline, aligned within 4PD, amblyopic eye visual acuity (VA) ≥0.3 logMAR, no concurrent patching or atropine treatment. Baseline factors examined were etiology, VA, stereoacuity, and prior patching treatment.
Results :
VA improved significantly after treatment in amblyopic children with HA (DVA=0.13±0.03; p=0.002) and HA+ET (DVA=0.12±0.03 logMAR; p=0.003). VA did not significantly improve in amblyopic children with MA (DVA=0.02±0.03 logMAR, p=0.53). There was a trend for more improvement in children with baseline VA of 0.7 logMAR or worse (DVA=0.17±0.06) compared to children with baseline VA of 0.3-0.6 logMAR (DVA=0.08±0.02 logMAR; p=0.07). VA outcome was not correlated with baseline stereoacuity or prior patching treatment.
Conclusions :
Amblyopia associated with hyperopic anisometropia, with or without corrected esotropia, improves with contrast-rebalanced binocular treatment while amblyopia associated with myopic anisometropia showed little response to treatment. Whether treatment failure is a result of early age of onset of amblyopia or structural changes in the eye associated with myopia is currently under investigation.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.