Evaluation of malignant invasion of the carotid artery by CT scan and ultrasound.

Carcinoma adherent to the carotid artery may be present in advanced head and neck cancers. Angiography, ultrasound, computerized tomography (CT), and magnetic resonance imaging (MRI) are available for the preoperative evaluation of the carotid artery. This study demonstrates that CT is not accurate in demonstrating malignant invasion of the carotid artery. Ultrasonography appears to be the best modality for assessing carotid artery invasion. Magnetic resonance imaging may prove helpful in this determination.