Carotid sheath

The carotid sheath helps to protect vital structures and provides a pathway for neurovascular bundles traveling to and from the head and neck. It is formed by contributions from multiple layers of deep cervical fascia. It encloses the vascular compartment of the neck, which includes the common and internal carotid aa., the internal jugular v., and the vagus n.  The carotid sheath extends upward from the arch of the aorta and terminates at the base of the skull (posterior to the sternocleidomastoid m.).