Recurrent Superior Oblique Myokymia Treated by Distal Tendon Extirpation

Abstract

Background: We describe successful surgical treatment of superior oblique myokymia, which had recurred after superior oblique tenectomy. Methods: Single case report. Results: The distal stump of the superior oblique tendon was extirpated by stripping it from the globe. The ipsilateral superior rectus muscle also was recessed, to correct a hypertropia that had resulted from the original superior oblique tenectomy. Conclusions: Complete removal of the distal superior oblique muscle tendon provided definitive relief of superior oblique myokymia. Superior rectus muscle recession, combined with previous inferior oblique myectomy, compensated effectively for loss of superior oblique function. Surgical treatment is a last resort for medically intractable superior oblique myokymia (1). The usual approach is a superior oblique tenotomy or tenectomy, combined with anticipatory inferior oblique recession or myectomy (2). Superior oblique myectomy with trochlear resection from an anterior orbitotomy approach also has been described(3), as well as nasal displacement (inverse Harada-Ito) of the anterior portion of the tendon (4). Occasionally, superior oblique myokymia can return after surgery. We treated a patient with recurrent superior oblique myokymia by excising the stump of the superior oblique tendon. The ipsilateral superior rectus muscle also was recessed to correct a residual hypertropia.