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Intracranial large artery atherosclerosis

As'ad Ehtisham, MD, MBBS, FAHA
Tanya N Turan, MD, MSCR
Section Editor
Scott E Kasner, MD
Deputy Editor
John F Dashe, MD, PhD


Atherosclerotic stenosis of the major intracranial arteries, also known as intracranial atherosclerosis (ICAS) or cerebral atherosclerosis, is an important cause of ischemic stroke. This topic focuses on the epidemiology, diagnosis, treatment, and prognosis of ICAS. Other ischemic stroke subtypes are reviewed separately. (See "Etiology, classification, and epidemiology of stroke" and "Clinical diagnosis of stroke subtypes" and "Lacunar infarcts" and "Cryptogenic stroke".)


Atherosclerosis is a pathologic process that causes disease of the coronary, cerebral, and peripheral arteries. Multiple factors contribute to the pathogenesis of atherosclerosis, including endothelial dysfunction, inflammatory and immunologic factors, plaque rupture, and the traditional risk factors of hypertension, diabetes, dyslipidemia, and smoking. The first stage of atherosclerosis begins in childhood with the development of fatty streaks, followed by progression involving the development of fibrous plaques, fibrous caps, and advanced atheromatous lesions. (See "Pathogenesis of atherosclerosis".)

Atherosclerosis is the most common cause of in situ local disease within the large extracranial and intracranial arteries that supply the brain (picture 1 and image 1). Intracranial atherosclerosis can lead to ischemic stroke or transient ischemic attack (TIA) by a variety of mechanisms (image 2), which include [1-3]:

In-situ thromboembolism leading most often to artery-to-artery embolism, and less often to hemodynamic insufficiency or to a combination of embolism and hemodynamic insufficiency [4]

Progression of luminal stenosis resulting in hemodynamic insufficiency

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Literature review current through: Oct 2017. | This topic last updated: May 25, 2017.
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