Superior oblique myokymia is intermittent spontaneous contractions of the superior oblique muscle presenting as rapid and small-amplitude intorsions and depressions of the eye. The authors report a case of superior oblique myokymia that was objectively and quantitatively diagnosed with slit lamp examination and video-oculography and completely resolved with medical treatment.

A 44-year-old woman presented with a seven-year history of intermittent oscillopsia which continued for few seconds. She had no history of head trauma or systemic ocular disease, and the anterior segment and fundus examination were unremarkable. Right eye intorsion lasting for a few seconds as detected by slit lamp examination. Eye movements were recorded using video-oculography, which showed a torsional nystagmus of 5 to 10 degrees with 2 to 5 vertical components in the right eye. Based on these findings, the patient was diagnosed with superior oblique myokymia. The patient was prescribed topical timolol ophthalmic solution, one drop twice per day, but the symptoms persisted. Timolol ophthalmic solution was stopped and replaced with carbamazepine, 200 mg twice a day, which resolved her symptoms.

Slit lamp examination and video-oculography can be used as objective and quantitative diagnostic tools in order to confirmed a diagnosis and lead to proper treatment.