Asterixis after unilateral stroke: lesion location of 30 patients.

The author describes 30 consecutive patients with unilateral stroke who had asterixis on presentation. The lesion location was as follows: thalamus in 19 (mostly, ventrolateral nucleus), frontal lobe in six, lenticulocapsular area in one, midbrain in two, and the cerebellum in two patients. Four patients had bilateral asterixis, and two patients with cerebellar lesions had ipsilateral asterixis. The asterixis may be caused by the abnormal control of arm posture maintenance due to functional dysregulation of the brainstem-spinal tracts from the cerebello-brainstem-thalamo-frontal lobe system.