Angiographic characteristics of radiation-induced carotid arterial stenosis

Purpose: This study aimed to clarify the angiographic characteristics of radiation-induced carotid stenosis. Methods: We evaluated 11 carotid arteries of patients after radiotherapy (radiotherapy group) and 26 carotid arteries of age- and gender-matched patients without a history of radiotherapy (control group). All patients had carotid stenosis detected by digital subtraction angiography (DSA). We developed an original coordinate system on the DSA to determine the accurate length and location of the carotid lesion. Results: Radiation-induced carotid lesions were significantly longer than carotid lesions caused by atherosclerosis. The maximal stenosis of radiation-induced carotid lesions tended to be at the end of the stenotic area and within a wider range than the nonradiation-induced lesions, including in the proximal common carotid artery (CCA). Conclusions: Radiation-induced stenotic lesions seem to exist in a wide range of carotid artery, including the CCA, along the vessel, and show maximal stenosis near the end of the stenotic area.