Circle of Willis

The Circle of Willis is the joining area of several arteries at the bottom (inferior) side of the brain. At the Circle of Willis, the internal carotid arteries branch into smaller arteries that supply oxygenated blood to over 80% of the cerebrum.

Update Date: 6/24/2011

Updated by: Reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

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