Treatment of Intracranial Hemorrhage Induced Hemichorea- Hemiballism by Low-Frequency Repetitive Transcranial Magnetic Stimulation.

An 80-year-old woman with a history of rheumatoid arthritis, hypertension, and hyperlipidemia, and no family history of hyperkinesis developed suddenly involuntary movement and visited our hospital two-day after onset. Neuro-examination revealed hemichorea-hemiballismus in the right side of the body, including the face (Suppl. video). Blood tests revealed neither hyperglycemia nor acanthocyte. Brain MRI showed acute microbleeding in the left subthalamic nucleus (Figure 1A-C). Although she was treated with haloperidol (max. 4.5 mg/day), hemichorea-hemiballismus did not subside. Repetitive transcranial magnetic stimulation (rTMS) with a low-frequency protocol (LFP) (1 Hz, 1200 pulses, with a stimulus intensity of 90% of the resting motor threshold, 3 days/week for 2-week) was applied to the left precentral knob (Figure 1D). Its effect was drastic, as the symptoms disappeared for half-hour after rTMS. Hemichorea-hemiballism then reappeared but was attenuated by repeated rTMS. The symptoms disappeared after one-month. Subthalamic nucleus lesions can develop hemichorea-hemiballism (1). According to a study on Huntington's disease and diabetic hemichorea-hemiballism, increased thalamocortical drive may increase the excitability of excitatory and inhibitory circuits of the frontal cortex as the etiologies of hyperkinesia (2-3). However, the target points of rTMS in treating hemichorea-hemiballism have not been consistent in literature. Moreover, rTMS with a LFP on the bilateral supplementary motor areas is effective in treating chorea in Huntington's disease (2). Additionally, rTMS on the ipsilateral precentral knob (primary motor cortex) with continuous θ burst stimulation (cTBS), which decreases the excitability and inhibitory cortical circuits, was effective in treating contralateral hemichorea caused by midbrain hemorrhage (3). Similar to cTBS, LFP can suppress cortical excitation (4); therefore, we applied rTMS with LFP on the primary motor cortex to treat hemichorea-hemiballism. Our results were drastic for both short- and long-term efficiency. This is the first report of the efficacy of rTMS with LFP in treating hemichorea-hemiballism caused by encephalorrhagia.