In order for a child to develop normal, healthy vision, the brain must receive clear and aligned images from both eyes. There are several conditions that can interfere with this process, and over a sufficient length of time, a child's developing brain can learn to permanently ignore the 'weaker' eye and favor the 'stronger,' or 'dominant' eye. This condition is called Amblyopia, commonly referred to as 'lazy eye.' Amblyopia is most commonly associated with misalignment of the eyes. It may also be caused by a large or unequal refractive error between the eyes. In rare cases, Amblyopia may result if vision is blocked by a cataract, corneal scar, droopy eyelid, or excessive patching therapy.