Bangerter filters hasten visual acuity recovery in children with anisometropic amblyopia

Researchers randomly assigned 66 children with anisometropic amblyopia to wear either spectacles alone or spectacles with a Bangerter fixed-density 0.3 filter on the spectacle lens of the better-seeing eye. Inclusion criteria were BCVA of 0.3 logMAR or more in the amblyopic eye and BCVA of 0.1 logMAR or less in the fellow eye. Amblyopia resolved significantly quicker in the Bangerter occlusion filter group after a mean of 2.2 months compared with 3.9 months in the spectacles-only group.

BCVA in the amblyopic eye significantly improved in both groups and was not significantly different between the groups after one year. Binocular function also improved in both groups and was similar after one year. Median spherical equivalent refractive error increased significantly in both amblyopic and fellow eyes in both groups after one year, while median anisometropia decreased significantly.