Fifty-three atheromatous carotid stenosis in a previously irradiated zone were operated upon between January 1983 and December 1991. A case control (retrospective) study confirmed the reality, even within the context of multiple artery atheromatous localizations, of an atypical profile suggestive of incrimination of the radiation: extension of the atheromatous lesions distally in the common carotid, proximally beyond the bulb. An isolated atheromatous lesion in the common carotid is very suggestive of postradiation atheroma, which also presents specific histologic features: peri-adventitial inflammation, adventitial and medial sclerosis. These changes are not accompanied by any particular neurologic clinical manifestations, but require frequent changes in surgical strategy: bypass rather than endarterectomy; the extent of the lesions decides whether the proximal implantation of the bypass is in the lower part of the common carotid or the subclavian. Radiotherapy adds to the difficulty of dissection and provokes a slight increase in morbidity, but the long term prognosis is analogous to that of usual atheromatous lesions with, however, the risk of atherosclerotic changes proximally.