Label The Arteries Of The Head And Neck

The arterial network of the head and neck is a complex and vital system, responsible for delivering oxygen-rich blood to the brain, face, scalp, and other critical structures. Understanding the anatomy and function of these arteries is crucial for medical professionals, students, and anyone interested in the intricacies of human biology. This detailed guide will walk you through the major arteries of the head and neck, providing a clear and comprehensive overview.

Major Arteries of the Head and Neck: An Overview

The primary source of arterial blood to the head and neck originates from the aortic arch. Branching off the aortic arch are the brachiocephalic trunk (on the right side) and the left common carotid artery and left subclavian artery (on the left side). The brachiocephalic trunk quickly bifurcates into the right common carotid artery and the right subclavian artery. From these main arteries, a series of branching vessels supply blood to various regions of the head and neck. We'll explore these in detail.

The Common Carotid Arteries

The common carotid arteries (CCA) are major vessels that ascend through the neck, providing the primary blood supply to the anterior part of the head and neck. There is a right and left common carotid artery.

• Origin: The right common carotid artery originates from the brachiocephalic trunk, while the left common carotid artery arises directly from the aortic arch.
• Course: Each common carotid artery ascends within the carotid sheath, alongside the internal jugular vein and vagus nerve.
• Bifurcation: At the level of the upper border of the thyroid cartilage (approximately at the C3-C4 vertebral level), the common carotid artery bifurcates into the internal carotid artery (ICA) and the external carotid artery (ECA). This bifurcation point contains the carotid sinus and carotid body, which are important in blood pressure regulation.

The Internal Carotid Artery

The internal carotid artery (ICA) is one of the two major branches of the common carotid artery. It primarily supplies blood to the brain, eyes, and forehead.

• Course: After branching from the common carotid, the internal carotid artery ascends superiorly, entering the skull through the carotid canal in the petrous part of the temporal bone. It then traverses the cavernous sinus before entering the cranial cavity.
• Branches: The internal carotid artery gives off several important branches:
  • Ophthalmic Artery: Supplies the eye and surrounding structures.
  • Posterior Communicating Artery: Connects the internal carotid artery to the posterior cerebral artery, forming part of the Circle of Willis.
  • Anterior Cerebral Artery (ACA): Supplies the medial surface of the cerebral hemispheres.
  • Middle Cerebral Artery (MCA): The largest branch of the internal carotid artery, supplying the lateral surface of the cerebral hemispheres.
  • Anterior Choroidal Artery: Supplies the choroid plexus of the lateral ventricle, as well as parts of the internal capsule, hippocampus, and optic tract.

The External Carotid Artery

The external carotid artery (ECA) is the other major branch of the common carotid artery. It supplies blood to the face, scalp, tongue, pharynx, and other external structures of the head and neck. The external carotid artery has eight major branches:

• Superior Thyroid Artery: Supplies the thyroid gland and larynx.
• Ascending Pharyngeal Artery: Supplies the pharynx, prevertebral muscles, middle ear, and cranial meninges.
• Lingual Artery: Supplies the tongue and floor of the mouth.
• Facial Artery: Supplies the face, including the lips, nose, and cheeks.
• Occipital Artery: Supplies the posterior scalp and neck muscles.
• Posterior Auricular Artery: Supplies the scalp behind the ear and the parotid gland.
• Maxillary Artery: A large and complex artery that supplies the deep structures of the face, including the teeth, palate, and nasal cavity.
• Superficial Temporal Artery: The terminal branch of the external carotid artery, supplying the scalp and temporal region.

Let's delve into each of these branches of the external carotid artery in more detail:

Superior Thyroid Artery

The superior thyroid artery arises from the external carotid artery near its origin and descends to supply the thyroid gland.

• Course: It runs inferiorly and medially, reaching the superior pole of the thyroid gland.
• Branches:
  • Infrahyoid Artery: Supplies the infrahyoid muscles.
  • Superior Laryngeal Artery: Pierces the thyrohyoid membrane to supply the larynx.
  • Sternocleidomastoid Branch: Supplies the sternocleidomastoid muscle.
  • Glandular Branches: Supply the thyroid gland, anastomosing with branches of the inferior thyroid artery.

Ascending Pharyngeal Artery

The ascending pharyngeal artery is the smallest branch of the external carotid artery and ascends along the pharynx.

• Course: It ascends deep to the internal carotid artery, supplying the pharynx and surrounding structures.
• Branches:
  • Pharyngeal Branches: Supply the pharyngeal muscles and mucous membrane.
  • Prevertebral Branches: Supply the prevertebral muscles.
  • Inferior Tympanic Artery: Supplies the middle ear.
  • Meningeal Branches: Supply the cranial meninges.

Lingual Artery

The lingual artery supplies the tongue and floor of the mouth.

• Course: It runs deep to the hyoglossus muscle, then ascends towards the tongue.
• Branches:
  • Dorsal Lingual Arteries: Supply the posterior part of the tongue.
  • Sublingual Artery: Supplies the sublingual gland and floor of the mouth.
  • Deep Lingual Artery: Runs along the underside of the tongue to its tip.

Facial Artery

The facial artery is a major artery that supplies the face.

• Course: It arises from the external carotid artery and courses anteriorly and superiorly, crossing the mandible and ascending towards the angle of the mouth.
• Branches:
  • Ascending Palatine Artery: Supplies the palate and tonsil.
  • Tonsillar Artery: Supplies the tonsil.
  • Submental Artery: Supplies the submental region.
  • Inferior Labial Artery: Supplies the lower lip.
  • Superior Labial Artery: Supplies the upper lip.
  • Lateral Nasal Artery: Supplies the side of the nose.
  • Angular Artery: The terminal branch of the facial artery, supplying the medial corner of the eye.

Occipital Artery

The occipital artery supplies the posterior scalp and neck muscles.

• Course: It arises from the external carotid artery and courses posteriorly, passing deep to the posterior belly of the digastric muscle and the sternocleidomastoid muscle.
• Branches:
  • Sternocleidomastoid Branches: Supply the sternocleidomastoid muscle.
  • Auricular Branch: Supplies the back of the ear.
  • Meningeal Branch: Supplies the dura mater in the posterior cranial fossa.
  • Descending Branch: Supplies the neck muscles.

Posterior Auricular Artery

The posterior auricular artery supplies the scalp behind the ear and the parotid gland.

• Course: It arises from the external carotid artery superior to the stylohyoid and digastric muscles and ascends posterior to the auricle.
• Branches:
  • Stylomastoid Artery: Supplies the middle ear.
  • Auricular Branches: Supply the auricle.
  • Occipital Branch: Supplies the scalp behind the ear.

Maxillary Artery

The maxillary artery is a large and complex artery that supplies the deep structures of the face. It is the larger of the two terminal branches of the external carotid artery.

• Course: It passes deep to the mandible and enters the infratemporal fossa. It then travels through the pterygopalatine fossa to supply the deep structures of the face.
• Branches: The maxillary artery has numerous branches, which are often divided into three parts based on their location relative to the lateral pterygoid muscle:
  • First Part (Mandibular Part):
    • Inferior Alveolar Artery: Supplies the lower teeth and chin.
    • Middle Meningeal Artery: Supplies the dura mater.
    • Accessory Meningeal Artery: Supplies the dura mater and the trigeminal ganglion.
  • Second Part (Pterygoid Part):
    • Deep Temporal Arteries: Supply the temporalis muscle.
    • Masseteric Artery: Supplies the masseter muscle.
    • Pterygoid Branches: Supply the pterygoid muscles.
    • Buccal Artery: Supplies the buccinator muscle and the buccal mucosa.
  • Third Part (Pterygopalatine Part):
    • Posterior Superior Alveolar Artery: Supplies the upper molar teeth and the maxillary sinus.
    • Infraorbital Artery: Supplies the lower eyelid, upper lip, and side of the nose.
    • Descending Palatine Artery: Supplies the palate.
    • Sphenopalatine Artery: The terminal branch of the maxillary artery, supplying the nasal cavity.

Superficial Temporal Artery

The superficial temporal artery is one of the two terminal branches of the external carotid artery (the other being the maxillary artery). It supplies the scalp and temporal region.

• Course: It ascends superficially in the temporal region, passing anterior to the ear.
• Branches:
  • Transverse Facial Artery: Supplies the parotid gland and the masseter muscle.
  • Anterior Auricular Branches: Supply the auricle.
  • Frontal Branch: Supplies the forehead.
  • Parietal Branch: Supplies the parietal region of the scalp.

The Vertebral Arteries

The vertebral arteries are another pair of major arteries that contribute to the blood supply of the brain.

• Origin: The vertebral arteries arise from the subclavian arteries.
• Course: They ascend through the transverse foramina of the cervical vertebrae (C6-C1) and enter the skull through the foramen magnum.
• Branches:
  • Spinal Branches: Supply the spinal cord.
  • Posterior Inferior Cerebellar Artery (PICA): Supplies the cerebellum and medulla oblongata.
• Basilar Artery: The two vertebral arteries join to form the basilar artery on the ventral surface of the pons.

The Basilar Artery

The basilar artery is formed by the union of the two vertebral arteries. It is a major artery that supplies the brainstem and cerebellum.

• Course: It ascends along the ventral surface of the pons.
• Branches:
  • Anterior Inferior Cerebellar Artery (AICA): Supplies the cerebellum and pons.
  • Pontine Arteries: Supply the pons.
  • Superior Cerebellar Artery: Supplies the cerebellum.
  • Posterior Cerebral Artery (PCA): Supplies the occipital lobe and the inferior temporal lobe.

The Circle of Willis

The Circle of Willis is a crucial arterial anastomosis located at the base of the brain. It connects the internal carotid and vertebrobasilar systems, providing collateral circulation in case of arterial occlusion. The Circle of Willis is formed by the following arteries:

• Anterior Cerebral Arteries (ACA)
• Anterior Communicating Artery: Connects the two anterior cerebral arteries.
• Internal Carotid Arteries (ICA)
• Posterior Cerebral Arteries (PCA)
• Posterior Communicating Arteries: Connect the internal carotid arteries to the posterior cerebral arteries.

Clinical Significance

Understanding the arterial anatomy of the head and neck is crucial for diagnosing and treating various medical conditions, including:

• Stroke: Occlusion or rupture of arteries in the head and neck can lead to stroke, resulting in neurological deficits.
• Transient Ischemic Attack (TIA): A brief interruption of blood flow to the brain, often a warning sign of a potential stroke.
• Carotid Artery Stenosis: Narrowing of the carotid arteries, increasing the risk of stroke.
• Temporal Arteritis: Inflammation of the temporal artery, causing headache and visual disturbances.
• Head and Neck Tumors: Knowledge of arterial supply is essential for surgical planning and embolization of tumors.
• Trauma: Injuries to the head and neck can damage arteries, leading to hemorrhage and ischemia.

Summary Table of Arteries and their Supply Areas

Conclusion

The arteries of the head and neck form a complex and interconnected network that is essential for supplying blood to the brain, face, and other vital structures. A thorough understanding of the anatomy and function of these arteries is crucial for medical professionals and anyone interested in human anatomy. This guide has provided a comprehensive overview of the major arteries of the head and neck, their branches, and their clinical significance. By mastering this knowledge, you can gain a deeper appreciation for the intricate workings of the human body and its vascular system.