Radiation-induced arterial injuries.

In a 20-year period from 1961 to 1981 at the University of Kentucky Medical Center, there were 20 patients with vascular lesions directly attributable to irradiation. Two distinct patterns of arterial injury attributable to radiotherapy were identified--arterial disruption and occlusion. Arterial disruption occurred in 12 patients--11 carotid blowouts and 1 iliac artery rupture. Two patients underwent prophylactic carotid artery ligation for impending rupture. In the 11 carotid artery ruptures, ligation of the artery in nine patients resulted in stroke or death in five patients. Iliac artery disruption necessitated ligation, which eventually led to severe ischemia requiring hip disarticulation. Unusual arterial stenosis or occlusion occurred in six patients 7 to 24 years after irradiation. Three patients had severe stenosis or occlusion of the common, internal, or external carotid arteries leading to cerebrovascular insufficiency. Three other patients with focal stenosis of the iliofemoral region were successfully treated with bypass grafting.