The intermittent form is the most common form of exotropia. Presentation is from birth to 5 years of age and very rarely afterwards.
There is usually a history of worsening exophoria. Closure of one eye in bright sunlight to avoid diplopia is an early sign. The divergence is greater for far than near. Convergence is normally good. Amblyopia and abnormal retinal correspondence are rare.
Concave lenses, antisuppression, or convergence exercises, may be of benefit in mild cases. Surgical correction is usually indicated when the exotropia is present more than 75% of the time, or there is evidence of progression of the deviation - a larger deviation, the development of exotropia on near fixation, or the development of suppression. Correction of the two lateral rectus muscles may be sufficient if deviation is mostly at distance. If there is deviation at near, it may be necessary to resect a medial rectus and weaken a lateral rectus. Overcorrection at the time of surgery may be advisable since exodeviations tend to recur . The condition may worsen to a constant exotropia.
Last reviewed 01/2018