Neck irradiation: A risk factor for occlusive carotid artery disease

Objectives: to determine whether irradiation is an independent risk factor for carotid atherosclerosis, and propose guidelines for patient follow-up. Design: a retrospective case control study. Materials and methods: two groups of patients with severe carotid artery stenosis (>70%) were compared: 30 post-neck irradiation patients, and a control group of 100 patients with no history of neck irradiation. Disease location and severity were assessed by duplex. The relationship between atherosclerotic risk factors, time since irradiation and carotid artery disease was examined. Results: the average age of study group patients was 67 years (43-86) compared to 69 years (46-89) in the control group. The average interval from irradiation to diagnosis was 14 years (3-53) (median 12.5 years). The study group suffered less from diabetes, ischaemic heart disease, and peripheral vascular disease (p<0.02). There were no significant differences among risk factors with respect to age, gender, smoking, hypertension, and hypercholesterolemia. Post-neck irradiation patients had a significantly higher prevalence of bilateral disease (p=0.02), and a higher rate of common carotid artery lesions (p<0.002). Conclusions: neck irradiation should be considered a risk factor for occlusive carotid artery disease. Preoperative angiographic study should be considered, due to frequent involvement of the common carotid artery.