Stenoses of the distal segments of the internal carotid artery.

In 31 of 51 patients with stenosis of the distal segments of the internal carotid artery, the first symptom was a transient ischemic attack. In spite of the high incidence of angiographically proved emboli, 46 patients remained in good neurological condition. Aspirin was given to all patients. In 4 patients a total occlusion developed, causing severe neurological deficit. This indicates that the danger of occlusion is significantly higher than that of embolization. External carotid-internal carotid artery bypass was carried out in 23 patients; occlusion developed during the postoperative observation period in 4 patients without any neurological consequences. It can be concluded that an EC/IC bypass operation is the method of choice in treating patients with severe distal stenosis or recent mural thrombi.