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Screening for asymptomatic carotid artery stenosis

Mark O McCarron, MD, FRCP
Larry B Goldstein, MD, FAAN, FANA, FAHA
David B Matchar, MD
Section Editors
Scott E Kasner, MD
Joann G Elmore, MD, MPH
Deputy Editor
John F Dashe, MD, PhD


The portions of the carotid artery most frequently affected by atherosclerosis are the proximal internal carotid artery (ie, the origin) and the carotid bifurcation. Progression of atheromatous plaque at the carotid bifurcation results in luminal narrowing, often accompanied by ulceration. This process can be asymptomatic, but may lead to ischemic stroke or transient ischemic attack from embolization, thrombosis, or hemodynamic compromise.

This topic will review screening for asymptomatic carotid atherosclerotic disease. The management of asymptomatic carotid disease is discussed separately. (See "Management of asymptomatic carotid atherosclerotic disease".)

Other aspects of carotid occlusive disease are reviewed elsewhere. (See "Pathophysiology of symptoms from carotid atherosclerosis" and "Evaluation of carotid artery stenosis" and "Management of symptomatic carotid atherosclerotic disease".)


Asymptomatic carotid atherosclerotic disease refers to the presence of atherosclerotic narrowing of the extracranial internal carotid artery in individuals without a history of ipsilateral carotid territory ischemic stroke or transient ischemic attack (TIA) [1-3].

Symptomatic carotid disease is defined as focal neurologic symptoms (eg, amaurosis fugax, contralateral weakness or numbness of an extremity or the face, dysarthria or aphasia) in the distribution of a carotid artery with a significant stenosis. Atherosclerotic carotid disease is considered symptomatic if the ipsilateral symptoms occurred within the previous six months. Importantly, nonspecific neurologic symptoms (eg, dizziness, lightheadedness) are not indicative of carotid stenosis. Therefore, patients with these symptoms in isolation should be considered as asymptomatic with regard to carotid disease even if they are found to have carotid artery stenosis. (See "Management of symptomatic carotid atherosclerotic disease", section on 'Definition of symptomatic disease'.)


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Literature review current through: Oct 2015. | This topic last updated: Sep 23, 2015.
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