[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Spine](https://durgical.com/en/anatomy/region/spine/) › Carotid arteries [Cardiovascular system](https://durgical.com/en/anatomy/system/cardiovascular-system/) · [Spine](https://durgical.com/en/anatomy/region/spine/) # Carotid arteries The carotid arteries are the main arteries in the front of the neck, one on each side; they carry blood to the head and brain. Official name: Common carotid artery [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=spine&select=carotid_arteries&side=r) Opens in the Durgical app, no sign-up needed. ## What it is The main arteries in the front of the neck, one on each side, splitting into internal (to the brain) and external (to the face and neck) branches. ## What it does Carry blood to the head and brain. In an ACDF the surgeon works just inside the carotid, which is gently held to the side. ## Key points - At the bifurcation lie the carotid sinus (baroreceptor) and the carotid body (chemoreceptor), both supplied by the [glossopharyngeal nerve](https://durgical.com/en/anatomy/glossopharyngeal-nerve/) - The [internal carotid artery](https://durgical.com/en/anatomy/internal-carotid-artery/) gives no branches in the neck, which tells it apart from the external carotid in surgery and on ultrasound - In the carotid sheath the artery lies medial, the internal jugular vein lateral and the vagus nerve behind, between the two - The anterior tubercle of C6 (carotid tubercle) lies behind the common carotid artery: the point against which it can be compressed and a level marker in anterior neck surgery ## Key facts **Origin** Right common carotid: [brachiocephalic trunk](https://durgical.com/en/anatomy/brachiocephalic-trunk/); left: aortic arch; bifurcate at upper border of thyroid cartilage (C3–C4) **Branches** Internal carotid (no neck branches; ophthalmic, anterior and middle cerebral); external carotid (superior thyroid, lingual, facial, occipital, maxillary...) **Supplies** Internal: anterior brain and eye; external: face, scalp, neck and upper airway ## Relations **Course** The right common carotid starts behind the sternoclavicular joint, the left in the thorax from the [aortic arch](https://durgical.com/en/anatomy/aortic-arch/); each rises in the [carotid sheath](https://durgical.com/en/anatomy/carotid-sheath/) to the upper border of the [thyroid cartilage](https://durgical.com/en/anatomy/thyroid-cartilage/) and divides; the internal carotid climbs to the [carotid canal](https://durgical.com/en/anatomy/carotid-canal/), the external to the parotid region **Lateral** [Internal jugular vein](https://durgical.com/en/anatomy/internal-jugular-vein/), inside the same carotid sheath **Behind** [Vagus nerve](https://durgical.com/en/anatomy/vagus-nerve/) within the sheath; behind the sheath, the [sympathetic trunk](https://durgical.com/en/anatomy/sympathetic-trunk/) on the prevertebral fascia, the [longus colli](https://durgical.com/en/anatomy/longus-colli-muscle/) and the cervical transverse processes **Medial** [Trachea](https://durgical.com/en/anatomy/trachea/) and oesophagus with the [recurrent laryngeal nerve](https://durgical.com/en/anatomy/recurrent-laryngeal-nerve/) in the groove between them, the [thyroid gland](https://durgical.com/en/anatomy/thyroid-gland/), the larynx and the [pharynx](https://durgical.com/en/anatomy/pharynx/) **Superficial** [Sternocleidomastoid](https://durgical.com/en/anatomy/sternocleidomastoid-muscle/), the infrahyoid muscles and the [ansa cervicalis](https://durgical.com/en/anatomy/ansa-cervicalis/) on the sheath; at the bifurcation only [skin](https://durgical.com/en/anatomy/skin/), [platysma](https://durgical.com/en/anatomy/platysma/) and fascia cover it (carotid triangle) ## How to find it The carotid pulse is felt at the anterior border of the sternocleidomastoid, roughly level with the top of the thyroid cartilage, pressing gently backward toward the transverse processes; one side is examined at a time. ## Examination - Auscultation over the bifurcation: a bruit suggests turbulent flow, such as from a stenosis, but its absence does not rule one out - Carotid sinus massage, done with monitoring: a long pause in the heartbeat or a large fall in blood pressure indicates carotid sinus hypersensitivity; as a vagal manoeuvre it can also slow or stop some supraventricular tachycardias ## On imaging Doppler ultrasound grades stenosis by flow velocity; the internal carotid is usually posterolateral, wider and branchless with a low-resistance waveform, the external has branches and a high-resistance waveform. CT or MR angiography maps the whole course. ## Clinical notes - Carotid endarterectomy removes plaque at the bifurcation; the hypoglossal, vagus (with its recurrent laryngeal branch), superior laryngeal and marginal mandibular nerves are at risk - Dissection of the internal carotid artery can cause neck pain, headache and a partial Horner syndrome, because the sympathetic fibres to the eye travel on its wall - Atherosclerosis concentrates at the bifurcation, where flow divides; emboli from plaque there cause transient ischaemic attacks, transient monocular blindness and stroke ## Anatomical variants - The left common carotid often shares an origin with the brachiocephalic trunk (the so-called bovine arch), the most common arch variant - The bifurcation is sometimes higher, near the [hyoid bone](https://durgical.com/en/anatomy/hyoid-bone/), which makes surgical exposure harder - The right common carotid rarely arises directly from the aortic arch ## Development The common carotid and the first part of the internal carotid come from the third pharyngeal arch artery, and the rest of the internal carotid from the dorsal aorta beyond it; the external carotid grows out later as a new branch. ## Memory aid External carotid branches: "Some Anatomists Like Freaking Out Poor Medical Students": Superior thyroid, Ascending pharyngeal, Lingual, Facial, Occipital, Posterior auricular, Maxillary, Superficial temporal. ## Related conditions - [Aortic dissection](https://durgical.com/en/conditions/aortic-dissection/) ## Test yourself Think of the answer, then tap the question to see it. ## At what level does the common carotid artery divide? At the upper border of the thyroid cartilage, about C3–C4. ## How is the internal carotid artery told apart from the external carotid in the neck? The internal carotid gives no branches in the neck; on ultrasound it is usually posterolateral, wider, with a low-resistance waveform. ## What lies at the carotid bifurcation, and which nerve supplies it? The carotid sinus (baroreceptor) and the carotid body (chemoreceptor), both supplied by the glossopharyngeal nerve. ## What is the arrangement of structures inside the carotid sheath? The carotid artery medial, the internal jugular vein lateral and the vagus nerve behind, between the two. ## Why can internal carotid artery dissection cause a partial Horner syndrome? The sympathetic fibres to the eye travel on the wall of the internal carotid artery. [Add to my cards (5)](https://durgical.app/estudiar/?add=/en/anatomy/common-carotid-artery/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** carotis communis; carotis interna; carotis externa TA2 4366 **Official Spanish (DeCS)** Arteria carótida común DeCS D017536 **English (TA2)** Common carotid artery ## Related - [Internal jugular vein](https://durgical.com/en/anatomy/internal-jugular-vein/) - [Vagus nerve](https://durgical.com/en/anatomy/vagus-nerve/) - [Sternocleidomastoid](https://durgical.com/en/anatomy/sternocleidomastoid-muscle/) Sources: Terminologia Anatomica (TA2); [DeCS](https://decs.bvsalud.org/es/ths/resource/?id=30798); [Anatomy, Head and Neck, Anterior: Common Carotid Arteries](https://www.ncbi.nlm.nih.gov/books/NBK546613/); [Anatomy, Head and Neck: Carotid Arteries](https://www.ncbi.nlm.nih.gov/books/NBK545238/); Anatomy of the Human Body (20th ed.): Development of the Vascular System (Lea & Febiger (Gray's Anatomy, 1918), 1918) · adapted, Public domain. ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/common-carotid-artery/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/common-carotid-artery/