Carotid Arteries

The carotid arteries are the four principal arteries of the neck and head. They have two specialized regions: the carotid sinus, which monitors the blood pressure, and the carotid body, which monitors the oxygen content in the blood and helps regulate breathing. The internal carotid arteries enter the skull to supply the brain and eyes. At the base of the brain, the two internal carotids and the basilar artery join to form a ring of blood vessels called the "circle of Willis." The external carotid arteries have several branches which supply the tissues of the face, scalp, mouth and jaws. The cavernous sinus lies at the base of the brain, adjacent to the temporal and sphenoid bones of the skull. It is an important structure because it holds nerves and veins, in addition to carrying large amounts of deoxygenated blood from the brain to the heart.