Hemiballismus due to contralateral sphenoid ridge meningioma

Primary intracranial tumour is a very uncommon cause of hemiballismus. In o ur review of the literature only two verified cases were found: one meningi oma and one meningoblastoma. We report a patient with right hemiballismus d ue to a contralateral meningioma of the sphenoid ridge. His symptoms disapp eared completely after resection of the tumour. The patient had no signs of increased intracranial pressure. Possible pathogenic mechanisms are briefl y discussed. A consequence of such an experience is that magnetic resonance imaging or computed tomography scans should bl made of every patient with uncommon extrapyramidal disorders, particularly if they do not respond to d rug therapy.