In the past 15 years, we have examined 20 patients in whom myokymia of the superior oblique muscle was diagnosed. Medical treatment (carbamazepine) failed in three patients, and one patient did not accept drug therapy. These four patients (20%) were operated on for persistent oscillopsia and diplopia. One patient underwent only a superior oblique muscle myotomy, but required an inferior oblique muscle myectomy six months later because of iatrogenic superior oblique muscle palsy. The other three patients underwent simultaneous superior oblique muscle myotomy and inferior oblique muscle myectomy. The symptoms resolved postoperatively in all four patients. Symptomatic patients with superior oblique muscle myokymia in whom medical treatment fails or is intolerable can benefit from surgical treatment consisting of combined superior oblique muscle/inferior oblique muscle myectomy.