Exotropia

Exotropia is a form of strabismus where an eye turns outward (deviation). People with exotropia often experience crossed double vision (diplopia).

The condition can be constantly present, or occur intermittently.

Right Constant Exotropia

Most Common Types of Exotropia

Constant Exotropia
A constant Exotropia, as the name implies, is present all the time, with and without glasses, and when attempting to focus at all distances. The earliest sign of exotropia is usually a noticeable outward deviation of the eye. The deviation may also be more noticeable when the child looks at something in the distance. Squinting or frequent rubbing of the eyes is also common with exotropia. A child probably will not mention seeing double, i.e., double vision. However, he or she may close one eye to compensate for the problem.

Generally, exotropia progresses in frequency and duration. As the disorder progresses, the eyes will start to turn out when looking at close objects as well as those in the distance. If left untreated, the eye may turn out continually, causing a loss of binocular vision.

Intermittent Exotropia
Intermittent Exotropia, again as the name implies, are not always present. Exotropia tends to manifest itself more often when daydreaming, the person tires, or is sick. Intermittent exotropia is a fairly common condition.
"Sensory exotropia" occurs in the presence of poor vision.

Infantile exotropia (sometimes called "congenital exotropia") is seen during the first year of life, and is less common than "essential exotropia" which usually becomes apparent several years later. 

Convergence Insufficiency
There is a uncommon form of exotropia known as "convergence insufficiency" that responds well to exercises. This disorder is characterized by an inability of the eyes to work together when used for near viewing, such as reading. Instead of the eyes focusing together on the near object, one deviates outward.

Because of the risks of surgery, and because about 35% of people require at least one more surgery, many people try exercises first. It is generally not covered by health insurance companies.

Treatment

The prognosis for each exotrope will depend upon the origin and classification of their condition. Generally, management may take the following course:

1. Identify and treat any underlying systemic condition.
2. Prescribe any glasses required and allow the patient time to 'settle into' them.
3. Where appropriate, orthoptic exercises can be used to attempt to restore binocularity.
4. Where appropriate, prismatic correction can be used, either temporarily or permanently, to relieve symptoms of double vision. This is rarely prescribed with minor children, but often with adults who do not cross enough to warrant surgery (microtropic).
5. Where necessary, extra-ocular muscle surgery can be undertaken to encourage proper alignment, cosmetic appearance, and, on occasion, restore binocularity.