Facial artery

The facial artery is a major branch of the external carotid artery that supplies blood to the structures of the face, including the lips, nose, and facial muscles. It plays a crucial role in vascularizing the superficial areas of the face.

Location

The facial artery arises from the external carotid artery, just above the lingual artery, near the angle of the mandible. It ascends obliquely, curving over the lower margin of the mandible at the anterior edge of the masseter muscle. From there, it travels upward and medially across the face, running beneath the platysma and zygomaticus muscles. The artery then winds its way toward the side of the nose and terminates near the medial angle of the eye as the angular artery. Along its course, the facial artery gives off several branches to supply the lips, nose, and cheeks.

Structure and Anatomy

Origin

The facial artery arises from the external carotid artery, typically at a point just superior to the origin of the lingual artery. It originates near the angle of the mandible, deep to the submandibular gland. The artery is usually the fourth branch of the external carotid artery, after the superior thyroid, lingual, and ascending pharyngeal arteries.

Course

The facial artery follows a tortuous path to accommodate facial movements and provide flexibility as it supplies the face with blood. It runs obliquely from its origin, passing deep to the digastric and stylohyoid muscles and then beneath the submandibular gland, which it supplies. After emerging from beneath the gland, the facial artery loops around the inferior border of the mandible, near the anterior edge of the masseter muscle. At this point, it becomes superficial and is palpable as it crosses the mandible.

From here, the artery ascends obliquely across the face, traveling beneath the platysma and zygomaticus muscles. It moves medially across the cheek toward the angle of the mouth, and from there, it continues toward the side of the nose. As it ascends, the facial artery sends off several branches to supply the lips, nose, and facial muscles. Finally, it terminates near the medial angle of the eye as the angular artery, the terminal branch of the facial artery.

Branches

Along its course, the facial artery gives off several important branches that supply various structures of the face and surrounding areas:

Cervical Branches:

• Ascending Palatine Artery: This branch runs upward along the pharynx and supplies blood to the soft palate, tonsils, and pharyngeal wall. It anastomoses with branches of the ascending pharyngeal and maxillary arteries.
• Tonsillar Branch: This small branch supplies the palatine tonsil and the surrounding region of the pharynx.
• Glandular Branches: These supply the submandibular gland, ensuring its proper vascularization.
• Submental Artery: This branch runs forward along the inferior surface of the mandible, supplying the mylohyoid muscle, chin, and the overlying skin and soft tissues. It also anastomoses with the inferior alveolar artery.

Facial Branches:

• Inferior Labial Artery: This artery arises near the lower lip and supplies blood to the lower lip and orbicularis oris muscle. It anastomoses with the superior labial artery on the opposite side.
• Superior Labial Artery: This artery arises near the upper lip and supplies the upper lip, nasal septum, and orbicularis oris muscle. It also gives small branches to the nasal ala and the nasal septum.
• Lateral Nasal Artery: This branch runs along the side of the nose, supplying the nasal ala, nasal septum, and surrounding tissues.
• Angular Artery: The terminal branch of the facial artery, the angular artery supplies the medial canthus (corner) of the eye, the upper part of the nose, and the surrounding facial tissues. It forms anastomoses with branches of the ophthalmic artery, a branch of the internal carotid artery, ensuring collateral circulation between the external and internal carotid systems.

Termination

The facial artery terminates as the angular artery, which supplies the region of the medial canthus of the eye and the lateral aspect of the nose. The angular artery also forms anastomoses with the dorsal nasal branch of the ophthalmic artery, contributing to the vascular supply of the nose and upper face.

Relationship with Surrounding Structures

As it courses through the neck and face, the facial artery is closely related to several important anatomical structures:

• Submandibular Gland: The facial artery passes deep to the submandibular gland, where it gives off glandular branches to supply the gland itself. This close relationship makes the artery vulnerable during procedures involving the gland, such as submandibular gland excision.
• Mandible: After emerging from beneath the submandibular gland, the facial artery crosses the inferior border of the mandible, near the anterior edge of the masseter muscle. This region is one of the places where the artery can be palpated for a pulse.
• Facial Muscles: The facial artery runs beneath several facial muscles, including the platysma, zygomaticus major and minor, levator labii superioris, and orbicularis oris muscles. It provides branches that supply these muscles, which are responsible for facial expressions.
• Facial Nerve (CN VII): The facial artery runs in close proximity to branches of the facial nerve, which innervates the muscles of facial expression. The relationship between the artery and nerve is particularly important during facial surgeries, where care must be taken to avoid damaging either structure.

Anastomoses

The facial artery forms numerous anastomoses with other arteries, providing a robust blood supply to the face. These include:

• Ophthalmic Artery: The angular artery, the terminal branch of the facial artery, anastomoses with the dorsal nasal branch of the ophthalmic artery, which arises from the internal carotid artery. This anastomosis creates a connection between the internal and external carotid artery systems.
• Submental and Inferior Alveolar Arteries: The submental artery anastomoses with the inferior alveolar artery (a branch of the maxillary artery), providing collateral circulation to the lower jaw and chin.
• Labial Anastomoses: The inferior labial artery anastomoses with its counterpart from the opposite side of the face, forming a rich blood supply for the lower lip. Similarly, the superior labial artery anastomoses with the artery on the opposite side to supply the upper lip and nasal region.

Variations

Anatomical variations in the facial artery are common, particularly in its course and branching patterns. In some individuals, the artery may follow a more superficial or deeper path in the face. The point at which the artery crosses the mandible and its tortuosity can also vary between individuals. Additionally, the facial artery may arise from a common trunk with the lingual artery, known as the linguofacial trunk. These variations are important considerations in surgical procedures involving the face and neck.

Surrounding Vascular Structures

The facial artery is located near several other important vascular structures, including:

• External Carotid Artery: The facial artery arises from the external carotid artery, along with several other branches, such as the lingual and superior thyroid arteries.
• Maxillary Artery: The facial artery shares a close relationship with the maxillary artery, another major branch of the external carotid artery that supplies deeper structures of the face, including the maxilla and mandible.
• Inferior Alveolar Artery: The submental branch of the facial artery anastomoses with the inferior alveolar artery, a branch of the maxillary artery, in the region of the lower jaw and chin.

Relations with the Face and Oral Cavity

As the facial artery ascends across the face, it supplies vital structures such as the lips, cheeks, nose, and muscles of facial expression. The artery’s tortuous course allows it to move with the skin and facial muscles, ensuring that it can continue to supply blood to the face even during movement or stretching of the tissues.

Function

Blood Supply to the Superficial Structures of the Face

The primary function of the facial artery is to provide oxygenated blood to the superficial structures of the face, including the skin, muscles, and tissues involved in facial expression. By delivering oxygen and nutrients to the facial muscles, such as the zygomaticus major, orbicularis oris, and buccinator, the artery ensures that these muscles function properly during activities like smiling, speaking, and eating. The artery also nourishes the overlying skin, contributing to the health, elasticity, and appearance of the face.

Blood Supply to the Lips

The facial artery supplies the upper and lower lips through its superior labial and inferior labial arteries, respectively. These branches play a crucial role in maintaining the integrity and function of the lips, which are essential for articulation (speech), eating, and facial expressions. The superior labial artery also contributes to the blood supply of the nasal septum and nasal ala, supporting the structure of the nose. By supplying the orbicularis oris muscle and surrounding tissues, the facial artery ensures that the lips can move and function effectively.

Blood Supply to the Submandibular Gland

The facial artery provides essential blood flow to the submandibular gland through its glandular branches. The submandibular gland is a major salivary gland, responsible for producing saliva, which aids in digestion and maintains oral hygiene. By delivering oxygen and nutrients to the gland, the facial artery ensures that the gland can function properly in producing and secreting saliva. This blood supply is critical for the health of the gland and its ability to support normal digestive and oral functions.

Blood Supply to the Palate and Pharynx

The ascending palatine artery, a branch of the facial artery, supplies blood to the soft palate, tonsils, and pharynx. These areas are involved in key functions such as swallowing, speaking, and respiration. The tonsillar branch of the facial artery further supplies the palatine tonsil, an important structure in the immune system that helps protect against infection. By supplying these regions, the facial artery contributes to the proper function of the oropharynx and its associated structures.

Blood Supply to the Nose and Nasal Septum

The lateral nasal artery and superior labial artery, both branches of the facial artery, supply the nasal septum and the nasal ala. These arteries help maintain the structural integrity of the nose, providing blood flow to support the cartilage, skin, and mucous membranes. Adequate blood supply to the nasal region is essential for respiration and for maintaining the health of the nasal tissues. The angular artery, the terminal branch of the facial artery, further supplies the medial canthus of the eye and the upper part of the nose, contributing to both cosmetic and functional aspects of the nose.

Collateral Circulation and Anastomoses

The facial artery plays a vital role in providing collateral circulation to the face. It forms important anastomoses with branches of the ophthalmic artery (which arises from the internal carotid artery), the inferior alveolar artery, and other facial arteries. These anastomoses ensure that the face receives a continuous supply of blood, even if one of the main arteries becomes blocked or compromised. The angular artery anastomoses with the dorsal nasal artery (a branch of the ophthalmic artery), providing an additional pathway for blood flow to the face, nose, and eyes.

Blood Supply to the Chin and Floor of the Mouth

The submental artery, a branch of the facial artery, supplies blood to the chin, the mylohyoid muscle, and the floor of the mouth. This is important for supporting the musculature and soft tissues involved in chewing, swallowing, and stabilizing the lower jaw. The submental artery also anastomoses with the inferior alveolar artery, ensuring a robust blood supply to the chin and lower jaw region.

Blood Supply to the Medial Canthus and Periorbital Region

The terminal branch of the facial artery, the angular artery, supplies blood to the medial canthus (corner) of the eye, the periorbital region, and the upper nose. The angular artery’s anastomosis with the ophthalmic artery allows it to provide a supplementary blood supply to the area around the eye and the nose. This is important for maintaining the health of the skin, muscles, and connective tissues in the periorbital region, particularly around the medial canthus, which plays a role in eye movement and tear drainage.

Nutrient Delivery and Waste Removal

Like all arteries, the facial artery ensures the delivery of oxygen, glucose, and other nutrients to the tissues it supplies. It plays a vital role in supporting the metabolism and function of the facial muscles, glands, and skin. In addition, the blood flow provided by the facial artery helps to remove metabolic waste products, such as carbon dioxide and lactic acid, from the tissues. Efficient circulation is crucial for maintaining healthy, functioning facial structures and supporting the skin’s natural regenerative processes.

Support for Facial Expression

The facial artery’s extensive branching allows it to supply the muscles of facial expression, including the zygomaticus major, buccinator, and levator labii superioris muscles. These muscles are responsible for creating expressions such as smiling, frowning, and other movements that are essential for communication and social interaction. By providing a constant blood supply, the facial artery ensures that these muscles receive the oxygen and nutrients they need to contract and function effectively during facial expressions.

Support for Tissue Repair and Healing

The facial artery plays a critical role in tissue repair and wound healing in the face. In cases of injury or trauma to the face, the artery supplies the necessary blood flow to support tissue regeneration and repair. Adequate blood flow is essential for the delivery of growth factors and immune cells to the site of injury, which helps to facilitate healing and prevent infection. The facial artery’s ability to provide blood to injured tissues makes it vital for facial surgeries and recovery from facial trauma.

Contribution to Thermoregulation

The facial artery contributes to thermoregulation in the face by adjusting blood flow in response to temperature changes. Increased blood flow to the superficial facial tissues allows heat to be dissipated through the skin, helping to cool the body during periods of physical exertion or exposure to warm environments. Conversely, when blood flow is reduced, it helps to conserve heat in colder conditions. This thermoregulatory function ensures that the face and superficial tissues maintain a stable temperature, even in changing environmental conditions.

Blood Supply to the Palatine and Tonsillar Regions

The facial artery, through its ascending palatine artery and tonsillar branch, supplies the soft palate, tonsils, and surrounding pharyngeal regions. These areas are involved in critical functions such as swallowing, speaking, and immune defense. By ensuring adequate blood flow to these areas, the facial artery supports their functional and immune roles in maintaining oral and respiratory health. The tonsils, in particular, benefit from the blood supply provided by the facial artery, as they are lymphoid tissues that play a role in protecting the body from pathogens.

Clinical Significance

The facial artery is of major clinical importance due to its role in supplying blood to the face, lips, nose, and surrounding structures. It is commonly encountered in various medical and surgical contexts.

Facial Trauma and Surgery

The facial artery’s superficial course makes it vulnerable to injury during facial trauma or surgical procedures such as facelifts, rhinoplasty, or tumor excisions. Damage to the artery can result in significant bleeding, and surgeons must carefully manage it to avoid complications. The artery is also a key landmark in reconstructive surgeries, particularly when performing flap procedures.

Pulse Point and Diagnostics

The facial artery can be palpated where it crosses the mandible, providing a useful site for assessing the pulse in clinical exams. This location is often used to assess circulation in the face and to detect abnormalities in blood flow, such as vascular occlusion or stenosis.

Cosmetic Procedures

In cosmetic procedures, such as dermal filler injections, knowledge of the facial artery’s course is critical to avoid inadvertent injection into the artery, which could lead to complications like vascular occlusion or skin necrosis. Careful planning around the artery’s path is necessary for safe aesthetic treatments.

Vascular Complications

In rare cases, the facial artery can be involved in arterial aneurysms, arteriovenous malformations (AVMs), or hemangiomas, requiring careful diagnostic and therapeutic approaches.