Superior oblique myokymia.

Superior oblique myokymia (SOM) is an uncommon, monocular movement disorder involving rapid torsional, low-amplitude contractions of the superior oblique muscle that causes monocular oscillopsia and diplopia. Ocular and neurologic examination in these patients is usually normal, and the clinical course is characterized by exacerbation remissions with good response to medical treatment. In this review, we present recent advances in the pathogenesis of SOM and provide an algorithm for the investigation and management of these patients.