Strabismic amblyopia occurs when a strabismus is present and the eyes are not aligned. The brain favours one eye over the other and the non-preferred eye is not adequately stimulated and the visual brain cells do not mature normally.
Anisometropia refers to the condition when the eyes have an unequal "refractive power". One eye may be nearsighted and the other is farsighted. Because the brain can not "balance" this difference, it picks the eye that is "easier" to use and develops a preference for this eye only.
Other causes of amblyopia include: cataracts, ptosis and trauma.
In most cases amblyopia is treatable. However, the success of treatment is dependent upon the initial level of vision, the amount of time the vision has been poor and the age of the child.