Cyclic esotropia is a rare form of strabismus; other forms of cyclic strabismus occur but are even rarer. Onset of cyclic esotropia is typically during the preschool years. The esotropia is comitant and intermittent, usually occurring every other day (48-hour cycle). Variable intervals and 24-hour cycles have also been documented.
Fusion and binocular vision are usually absent or defective on the strabismic day, with marked improvement or normalization on the orthotropic day. Occlusion therapy may convert the cyclic deviation into a constant one.
Surgical treatment of cyclic esotropia is usually effective. The amount of surgery is based on the maximum angle of deviation present when the eyes are esotropic.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.