Head and Neck
The left common carotid artery (CCA) arises directly from the aorta, while the right CCA arises from the brachiocephalic trunk.
Each CCA bifurcates at the level of T4 into two branches:
External carotid artery (ECA): Gives multiple branches, including the superficial temporal, lingual, and maxillary
Internal carotid artery (ICA): Passes through the carotid foramen into the inside of the skull and forms the circle of Willis; see Chapter 3, Neuroanatomy, for more details
Face: Drains into the internal jugular vein (IJV) via the facial vein
Brain: Drains into the dural venous sinuses; see Chapter 3, Neuroanatomy.
Note: The facial vein is connected to the cavernous sinus, so an infection of the face may be transmitted intracranially, causing cavernous sinus thrombosis.
Carotid Sheath and Neck Triangles
Carotid sheath: Contains common carotid artery (medially), internal jugular vein (laterally), and vagus nerve (posteriorly)