Corpus: Common carotid artery

The common carotid artery, abbreviated as CCA, is a large-caliber artery that originates from the brachiocephalic trunk on the right side and directly from the aortic arch on the left side. It supplies a large part of the head and neck with arterial blood.

The common carotid artery runs under the sternocleidomastoid muscle and lateral to the trachea from the upper thoracic aperture towards the head. The left CCA can be divided into a thoracic part and a cervical part. This division is not practical for the right CCA because the thoracic part is very short. The average vessel diameter is 6.5 mm in men and 6.1 mm in women.^[1]

At the so-called carotid bifurcation (bifurcatio carotidis), the vessel divides into:

• Internal carotid artery (ICA)
• External carotid artery (ECA)

The height of the carotid bifurcation varies greatly between individuals. It usually projects onto the 4th cervical vertebra, but can also be 1 to 2 segments further cranial or caudal. Typically, the common carotid artery does not give off any branches along its course.

The carotid artery is embedded in the carotid sheath, a part of the cervical fascia. It also encloses the internal jugular vein, which runs lateral to the artery, and the vagus nerve, which is situated between the two vessels. Each of these three structures has its own connective tissue sheath.

In its lower section, the common carotid artery lies deep in the neck, covered by the skin, superficial cervical fascia, platysma, middle cervical fascia, sternocleidomastoid muscle, sternohyoid muscle, sternothyroid muscle, and omohyoid muscle. In the upper part, the vessel is closer to the surface, covered only by the skin, superficial cervical fascia, platysma, middle cervical fascia, and the medial edge of the sternocleidomastoid muscle.

The carotid pulse can be palpated on the common carotid artery. The most significant disease of the common carotid artery is atherosclerotic carotid stenosis, which is usually located at the bifurcation.

• 3D model brachial plexus - anatomical situs; Dr Claudia Krebs (Faculty Lead) University of British Columbia