Vertebral Artery Ultrasound.

There is renewed interest in ultrasound imaging of the vertebral artery due to the increasing use of stent placement for treating vertebral artery stenosis. Changes in vertebral artery waveforms are helpful in detecting pathologic processes involving the proximal and distal neurovascular circulation. We review the normal anatomy, scanning technique, normal gray scale, and color Doppler ultrasound appearance and differential diagnosis of spectral Doppler waveform changes in the extracranial vertebral artery. We review the ultrasound criteria for diagnosing vertebral artery stenosis, and the imaging appearance of non-atherosclerotic pathology that may affect the vertebral artery, including dissection, pseudoaneurysm, and arteriovenous fistula.