Question: What are the key components of cerebral circulation? Georgia Subscriber Answer: Before you attempt coding for embolism in the cerebral arteries, you must understand the key components of cerebral circulation. There are two main parts of the cerebral circulation: The anterior, middle, and posterior cerebral arteries on the right and left side together with the anterior and posterior communicating arteries form a relatively circular array of blood vessels at the base of the brain called the Circle of Willis. The arteries that arise directly from the basilar artery supply the cerebellum. Besides these key vascular branches, there are other named arteries like the anterior communicating arteries, posterior inferior cerebellar arteries, pontine arteries, and others.