[Changes of electroencephalographic findings in a case of migraine with various neurological symptoms].

We report here an 1-year-old boy who was diagnosed as sporadic hemiplegic migraine demonstrated transient changes in electroencephalographic (EEG) background activity accompanied with migraine attacks. The attacks were associated with various neurological complications such as impairment of consciousness and hemiplegia and so on, which coincided with the changes of EEG findings. When his first headache developed with fever and impairment of consciousness, diffuse slow waves (1-2 Hz, 250-300 microV) appeared transiently. The slow wave gradually improved thereafter, and disappeared on the 24th day. On the 25th day, when he had the second attack with left hemiplegia and impairment of consciousness and sensation, slow waves, (2-3 Hz, 250-300 microV) appeared on right side of the brain. Constriction of the right middle cerebral artery was found on MR angiography at that time. The EEG change had improved to normal background activity 3 days after the episode. This unique case demonstrated that transient EEG changes seem to be correlated with the existence of unconsciousness and the laterality of the ischemic insult. We may assume that the changes of electroencephalographic findings may represent the cortical dysfunction caused by vascular constriction.