How are the extracranial carotid arteries evaluated sonographically?
Sonographic evaluation of the carotid arteries in the neck involves gray scale imaging to detect wall thickening, plaque, and the degree of luminal narrowing. Color spectral Doppler imaging is used to demonstrate the presence and direction of blood flow as well as the velocity of blood flow. Normally, the internal carotid artery (ICA) has low-resistance flow, whereas the normal external carotid artery (ECA) has high-resistance flow, and the common carotid artery (CCA) is a hybrid waveform of the ICA and ECA.
