Much of the brain is supplied blood by the internal carotid arteries.
The internal carotid arteries branch at the base of the brain in an area called the circle of Willis.
A blood clot (thrombus) may form in the body, break-off, and travel to the brain through a carotid artery and the circle of Willis.
The blood clot may block the passage of blood through a brain artery, depriving nearby tissue of oxygen and nutrients. The result is a stroke.
Review Date: 5/21/2012 Reviewed By: Luc Jasmin, MD, PhD, Department of Neurosurgery at Cedars-Sinai Medical Center, Los Angeles, and Department of Anatomy at UCSF, San Francisco, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.