Computed tomography and EEG in cerebrovascular disease.

In three patients with cerebrovascular diseases, the EEG showed active dysfunction of varied extent and severity in one cerebral hemisphere, but computed tomography showed no demonstrable abnormalities in the corresponding areas. These patients had occlusion or severe stenosis of one or both internal carotid arteries, either extracranially or intracranially. Both clinical symptoms and the EEG abnormalities resolved or improved after surgical anastomosis of the superficial temporal artery to the middle cerebral artery.