Abstract
Background and Purpose: Carotid stenosis is known to occur after neck radiotherapy. However, there are few reports of radiation-induced carotid artery lesions in patients with neck cancers in Japan. This study aimed to clarify the ultrasonographic characteristics of radiation-induced carotid artery lesions.
Methods: We evaluated 11 patients after neck radiotherapy for pharyngeal or laryngeal cancer. The mean time from radiotherapy to carotid ultrasound sonography was 55.6 months (range: 3–156 months). The carotid artery diameter, maximum intima medial thickness (max-IMT), peak systolic velocity (PSV), and distribution and properties of plaques were measured using carotid ultrasound sonography.
Results: All patients had increased IMT of the bilateral carotid artery. There was a linear correlation between the max-IMT and the duration of the post-radiation therapy interval. Four of the 11 patients (36%) developed carotid stenosis greater than 50% on the bilateral carotid artery, and their plaques were all unstable. Two patients developed cerebral infarctions at a mean of 12.3 years following radiotherapy.
Conclusion: Radiation-induced carotid artery lesions have a wide range of clinical courses in the bilateral carotid artery. Periodic carotid ultrasonography examinations are necessary to detect radiation-induced carotid artery lesions.
