The essentials of extracranial carotid ultrasonographic imaging.

In this article, the standard ultrasonographic scanning techniques and Doppler settings necessary to produce reliable and reproducible carotid imaging are discussed. The normal carotid anatomy is reviewed, including grayscale, color Doppler, and spectral Doppler imaging appearances, is reviewed. The vascular abnormalities caused by atherosclerosis are examined, including plaque morphology characterization as well as waveform and velocity changes caused by stenosis, are examined. In addition, special situations are explored, such as imaging in the presence of an arrhythmia or cardiac assist devices. Imaging after carotid intervention is discussed, including the complications associated with these procedures.