What is Amblyopia?
Amblyopia, also known as lazy eye, is characterized by reduced vision not correctable by glasses or contact lenses.  With amblyopia, the brain does not fully interpret the images seen by the amblyopic eye.  It will normally only affect one eye.

Causes of Amblyopia
Amblyopia can be caused by anything that interferes with clear vision during the critical brain development years from birth to 6 years old.  Common causes include visual differences between the two eyes (a different prescription for each eye that is uncorrected), crossing or turning of the eye that can cause double vision (strabismus), or a blockage of vision such as with a cataract or eye injury.  When one eye can see clearly, the brain begins to shut off or ignore the images from the eye with the blur or weaker vision.  In cases of strabismus (crossing), suppressing the image from one eye can eliminate double vision.  The suppression of vision can result in a permanent vision loss that cannot be corrected by glasses, contacts or laser surgery. 

Diagnosis of Amblyopia
Because lazy eye usually only affects one eye, it can be difficult to detect by the child or a parent because the child seems to be able to see normally. And usually they can--through their "good" eye.  An eye exam performed at a pediatrition's office or using a 20/20 screening chart is not adequate in diagnosing lazy eye.  For this reason, amblyopia is often left undetected until a child recieves a comprehensive eye exam by an eye doctor.  Often this happens when the child is older and treatment is much delayed.  It is highly recommened that full eye exams are performed for infants and pre-school age children.

Treatment of Amblyopia
Many doctors treat amblyopia by placing a patch over the child's "strong" eye, thus helping ot retrain the brain to use the "weak" eye.  Doctors may prescribe patching for just a short time each day or week, or nearly all waking hours.  Other forms of treatment include drops that blur vision in the strong eye and vision therapy.  A combination of treatment types may also be used.  Usually, the younger the child is when treatment begins, the higher chances of recovering full function of the eye. It is common to treat the cause of the amblyopia while treating the amblyopia itself.  For example a child might begin to wear glasses to correct visual differences of each eye, while patching to train the brain.  A child may require eye muscle surgery to correct strabismus (eye crossing) or surgical removal of cataracts so that as the amblyopia is corrected, these conditions do not cause the brain to regress again