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Carotid artery stenosis in patients who have undergone radiation therapy for head and neck malignancy.

Although it is established that small and medium sized arteries undergo extensive radiation damage, the effect on large vessels such as the carotid arteries is less well understood. We sought to determine if an increased severity of carotid artery stenosis is present in patients who have undergone radiotherapy for head and neck tumours. 45 patients aged 43-90 years (average 67) with head and neck malignancies treated with radiotherapy underwent colour Doppler ultrasonographic scanning of the carotid arteries. These patients were compared with a population of asymptomatic historical controls. 60% of patients demonstrated stenosis ranging from 21 to 86%. 38% of patients demonstrated a stenosis greater than or equal to 50%. Carotid artery stenosis appears to be increased in patients who have previously undergone treatment with radiotherapy to the head and neck regions compared with controls (p < 0.001). These findings suggest that radiation has an adverse effect on large vessels. Colour Doppler follow-up may be indicated for patients receiving head and neck radiation therapy.