About Amblyopia

Commonly referred to as a "lazy eye," amblyopia is not what many people think it is. When a child has crossed eyes or one eye that does not track along with the other (it turns in or out instead), many people incorrectly call that a lazy eye, but the correct term for that is "strabismus." While strabismus can contribute to or cause amblyopia, they are not the same thing.

Definition

• Amblyopia is the name given to explain the condition when vision is impaired, but it cannot be attributed to any disease, nor can it be corrected with lenses such as eyeglasses or contacts, or surgery.

Cause

• The time between birth and age 6 is a critical time for the development of the eyes and their ability to focus together to produce clear images. Sometimes, something will impair the development of one eye's vision or the ability of the eyes to focus together--such as a strabismus (turned eye), injury or trauma to one eye, or different visions in the eyes that is not immediately discovered and corrected with lenses. As a result, one eye sees better than the other and the brain learns to process vision with just the good eye, effectively blocking the other eye's messages. After a time, the brain is so conditioned to ignore the blurred images from the poorer eye that the eye develops a permanent vision impairment otherwise known as amblyopia.

Symptoms

• Most amblyopia occurs initially in children under the age of 6, so absent a strabismus or some other visible indicator that the child may not be seeing correctly, it often goes undetected. However, a parent who pays close attention may note their child has difficulty focusing, closes one eye or squints frequently, or suffers from frequent headaches, which may prompt an early eye examination.

Danger

• If untreated, amblyopia becomes permanent, resulting in partial or significant loss of vision in one eye. This will also result in difficulty with depth perception (steropsis)--the process that results when the two eyes focus together to interpret how dimensional an object is.

Diagnosis

• Infants and toddlers should undergo complete eye examinations that may include an examination with cycloplegic drops. Often, amblyopia goes undiagnosed and untreated until children enter school if there is no strabismus to suggest something may be wrong with the child's vision. The longer it takes to detect amblyopia, the harder it is to correct.

Treatment

• Treatment is most effective when it starts early. With small children, eye drops, glasses or patching the good eye can sometimes correct the amblyopia. Other forms of vision therapy are also utilized as needed.