Lazy eye
Amblyopia or lazy eye is a disorder of the eyes. It is characterised by poor or blurry vision in an eye that is otherwise physically healthy and normal. The problem is due to either no transmission or poor transmission of the visual image to the brain for a sustained period during early childhood. The condition will only arise at this young age because most of the visual development in humans is complete and "locked in" by a few years of age. Amblyopia normally only affects one eye, but it is possible to be amblyopic in both eyes if both are similarly deprived of a good, clear visual image.
Amblyopia is relatively common; it affects 2-5% of the population. If it is detected early enough, it may be corrected by occluding the stronger eye for periods of time to force the weak eye to develop good vision. In actuality, it is a brain problem and not an eye problem. The part of the brain corresponding to the visual system from the affected eye is not stimulated properly and will, therefore, develop abnormally. This has been confirmed in brain specimens. This treatment rarely works for adults, since the visual system is fully developed before adolescence. However, recent research has shown that some therapy can improve visual acuity slightly in adult amblyopes.
Many children who have amblyopia, especially those who are only mildly amblyopic, are not even aware they have the condition until tested at older ages, since the vision in their stronger eye is normal. However, people who have severe amblyopia may experience associated vision disorders, most notably poor depth perception.
Amblyopia can be caused by a number of conditions, including strabismus (misaligned eyes), vision obstructing disorders and anisometropia (different degrees of myopia or hyperopia in each eye). Since strabismus is a common cause of amblyopia, it is sometimes also referred to as "lazy eye."
