[Cerebral embolism with hemiballism due to putaminal lesion].

A 66-year-old man was admitted to our hospital because of hemiballism of his left extremities. The hemiballism disappeared soon after beginning therapy with haloperidol and chlorpromazine. X-ray CT brain scan on day 3 showed infarction in the right putamen and the right parietal lobe. Cerebral angiography on day 9 was normal. Transesophageal echocardiography revealed no abnormality except for an atrial septal aneurysm. Transcranial color-flow imaging demonstrated high intensity transient signal (HITS) with Valsalva maneuver. Paradoxical embolism was, therefore, thought to have caused the patient's brain infarction. It was speculated that the hemiballism was caused by disinhibition of the cortex resulting from loss of negative feedback in the motor system due to the putaminal lesion. It is necessary to treat hemiballism using an appropriate therapy to prevent exacerbation.