The optical treatment of amblyopia.

The role of refractive correction has been underestimated as a distinct component of amblyopia therapy. Until relatively recently, the extent to which it could ameliorate the amblyopic acuity deficit remained unquantified and the time course of its effect unknown. Improvement of vision after refractive correction appears to occur in all the major types of amblyopia, including, somewhat surprisingly, in the presence of strabismus. Although the neurophysiological basis of the remediative effect of such "optical treatment" is unknown, some insight is now available from animal models and psychophysical investigations in humans. An appreciation of the role that refractive correction can play in the overall management of amblyopia has led to the formulation of new treatment guidelines, whereby a defined period of spectacle or contact lens wear always precedes traditional therapies, such as occlusion or penalization.