What is Amblyopia or Lazy Eye?
Lazy eye is a commonly used term for Amblyopia. This is a condition involving reduced vision in an eye that appears unrelated to any eye disease. The brain is simply unable to see well with the images provided by that eye even with the right glasses. Amblyopia is generally caused by the failure of the eye to develop properly in the early years of life. It is associated more frequently with low birth weight or premature birth. Current statistics estimate the prevalence of this condition between 2-4% of all children.
What causes Amblyopia?
Amblyopia is most often associated with an inability to use both eyes together. There are three common causes:
1) Strabismus— The eyes may turn in, out or be vertical misaligned preventing the eyes from looking at the same object at the same time.
2) Visual Deprivation — This is when vision is optically obstructed in one or both eyes. Example: Congenital Cataracts
3) Anisometropia— An optical disparity in the glasses prescription between the two eyes that prevents the eyes from working together. The brain chooses to see with the eye that has the clearer picture and shut off the more blurred one. The eye that is ignored gradually loses its ability to see even with glasses.
How is Amblyopia diagnosed?
Children often feel that their vision is just fine. Since they use both eyes at once, the good eye takes over for the bad one. Signs of this condition may involve crossed eyes, the shutting one eye when trying to focus or bumping into objects usually often. A comprehensive eye exam by your eye doctor can detect amblyopia quite readily where screenings may not. Since early treatment dramatically improves the prognosis for this condition, getting the child to your family optometrist at a young age is critical. Current recommendations of the American Optometric Association call for the first eye examination at 6 months of age, at age three, and when the child starts school.
How is Amblyopia treated?
Spectacles, prisms and contact lenses are used to provide a focused image for the bad eye. Often, the good eye will be patched to force the weak eye to work. In more difficult cases, a program of vision therapy can often improve vision. Finally, extreme cases of children with strabismus (crossed eyes) may require surgery as an adjunct to the more primary treatments.
The important thing to realize is that this condition can often be successfully resolved if detected and treated early enough. Prognosis declines as the as we get older and the visual system matures. For this reason, the first eye exams are critical.
By Dr. Ric Munz
Eye Doctor | Wake Forest
Doctors Vision Center