Related Sites:     ISRS   |   AAOE   |   EyeSmart   |   EyeCare America   |   Academy Foundation   |   EyeWiki
Find an Eye M.D.     About     Newsroom     Help


Photo by Sandra Brown, M.D.
Patched eye
This child has his eye patched in order to force him to fixate (place his fovea on) viewed objects with the non-occluded eye. He has strabismus, or misalignment of the eyes, with one eye fixating, the other eye deviating.

The nonfixating eye has developed amblyopia, a loss of visual acuity owing to disuse. By forcing him to fixate with the non-occluded eye, amblyopia can usually be reversed, provided it has not been present too long.

Amblyopia is the loss of visual acuity owing to visual deprivation or suppression of a retinal image. It is a kind of disuse atrophy that occurs only within the first five years of life, when the visual connections are still being modeled. During that time, neural connections will dissipate if the fovea of one eye is not receiving a clear image of a viewed object. Fortunately, these connections can be restored if the fovea gets a clear image soon enough.

Amblyopia arises in one of four settings: 1) strabismus, or ocular misalignment; 2) anisometropia, or marked discrepancy between the refractive errors of the two eyes; 3) a corneal or lens opacity that degrades the image quality on the retina; and 4) ptosis that blocks any image from reaching the retina.

The treatment of amblyopia depends on its cause. In strabismus, the eyes must be realigned. In anisometropia, the refractive errors must be corrected. Media opacities and ptosis must be removed.

In most cases, the non-amblyopic eye must be occluded in order to force the amblyopic eye to fixate. The younger the patient, the shorter the period necessary to reverse amblyopia. In some cases, repeated patching must be done to prevent amblyopia from recurring. After age six, amblyopia is unlikely to occur.

What to do?
Refer to an ophthalmologist non-urgently if the patient is less than 12 years old and has not had intensive treatment of amblyopia. In patients beyond age 12, amblyopia is not amenable to therapy.

 Previous Next