Noninvasive assessment of neck vessel pathology.

Clinical trials (NASCET, ECTS) have shown that carotid endarterectomy is protective against stroke in patients with symptomatic severe carotid stenosis. To decrease costs and risks, new diagnostic tools have been developed, such as duplex ultrasound (DUS), magnetic resonance angiography (MRA), and more recently computed tomography angiography (CTA). CTA and MRA provide excellent 3D angiography images of the extracranial vessels, using a volume-rendering technique. Digitally subtracted MRA (DSA-MRA) obtained with high-speed acquisitions during gadolinium injection has also recently become available. These techniques are changing the role of non-invasive assessment of carotid stenosis. Although it is probably too early to assess a definite diagnostic algorithm, the use of DSA as a pre-surgical tool for defining carotid stenosis is rapidly decreasing.