The treatment of superior oblique myokymia utilizing the Harada-Ito procedure.

A woman with superior oblique myokymia (SOM) was cured of her condition by performing a Harada-Ito procedure. This procedure involves transposing the anterior portion of the superior oblique tendon, which is responsible for cyclorotation, nasally to create an effective weakening of the anterior portion of the tendon instead of temporal displacement utilized for superior oblique paresis. We measured the patient's eye movements before and after surgery, using the magnetic search coil technique, and confirmed that (1) the SOM was abolished and (2) vertical eye movements, including saccades, were unaffected.