Common carotid artery Common carotid artery In anatomy, the left and right common carotid arteries (carotids) () are arteries that supply the head and neck with oxygenated blood; they divide in the neck to form the external and internal carotid arteries. The common carotid arteries are present on the left and right sides of the body. These arteries originate from different arteries but follow symmetrical courses. The right common carotid originates in the neck from the brachiocephalic trunk; the left from the aortic arch in the thorax. These split into the external and internal carotid arteries at the upper border of the thyroid
Human brain been shown with lymph valves, to be more extensive at the base of the brain where they exit with the cranial nerves. The internal carotid arteries supply oxygenated blood to the front of the brain and the vertebral arteries supply blood to the back of the brain. These two circulations join together in the circle of Willis, a ring of connected arteries that lies in the interpeduncular cistern between the midbrain and pons. The internal carotid arteries are branches of the common carotid arteries. They enter the cranium through the carotid canal, travel through the cavernous sinus and enter the