The superficial temporal artery is one of the two terminal branches of the external carotid artery, the other being the maxillary artery. It is responsible for supplying blood to the scalp and portions of the face and temporal region. This artery plays a vital role in the vascular network of the head and face.
Location
The superficial temporal artery arises from the external carotid artery in the parotid gland region, near the neck of the mandible. It ascends through the parotid gland, passes in front of the ear, and travels upward along the side of the head. It runs superficially over the temporalis muscle and beneath the skin of the temporal region, giving off several branches that supply the scalp, forehead, and portions of the face.
Structure and Anatomy
Origin
The superficial temporal artery is one of the two terminal branches of the external carotid artery, with the other being the maxillary artery. It arises within the parotid gland, at the level of the neck of the mandible, near the posterior aspect of the jaw. This location, just deep to the parotid gland, marks the beginning of the artery’s course.
Course
After its origin, the superficial temporal artery ascends vertically, traveling through the parotid gland and emerging at the anterior border of the external acoustic meatus (the ear canal). It runs anterior to the tragus of the ear, where it becomes more superficial, lying just beneath the skin. From here, the artery continues upward along the temporal region of the head, superficially over the temporalis muscle. It can be easily palpated in the temple area due to its superficial position.
Branches
As it ascends, the superficial temporal artery gives off several important branches, each contributing to the vascular supply of the head and face. The key branches include:
- Transverse Facial Artery: This branch originates from the superficial temporal artery as it crosses the zygomatic arch and runs horizontally across the face, supplying the parotid gland, facial muscles, and skin of the lateral face.
- Frontal Branch: This is one of the terminal branches of the superficial temporal artery. It ascends toward the forehead, supplying the scalp in the frontal region, as well as the forehead and upper face.
- Parietal Branch: Another terminal branch, the parietal branch ascends toward the parietal region of the skull, supplying the scalp in the upper, lateral portion of the head.
- Zygomatico-orbital Artery: This branch runs along the lateral part of the orbit and supplies the tissues around the zygomatic bone and the lateral aspect of the eye.
- Middle Temporal Artery: This artery branches off near the root of the superficial temporal artery and pierces the temporalis fascia to supply the temporalis muscle.
Anastomoses
The superficial temporal artery forms important anastomoses with other arteries in the head and face. Notable anastomoses include those with the supraorbital and supratrochlear arteries (branches of the ophthalmic artery), which contribute to the vascular supply of the scalp and forehead. These connections help form a robust vascular network in the face and scalp, allowing for efficient blood flow even if one branch is compromised.
Termination
The superficial temporal artery terminates by dividing into two main branches: the frontal branch and the parietal branch. The frontal branch continues toward the forehead, while the parietal branch supplies the upper portion of the scalp. Both terminal branches contribute to the blood supply of the scalp and form further anastomoses with other vessels in the region, ensuring a continuous blood supply to the tissues of the head.
Surrounding Structures
As it travels through the parotid gland and ascends in front of the ear, the superficial temporal artery is closely related to several important anatomical structures, including:
- Parotid Gland: The artery passes through this large salivary gland near its origin.
- Auriculotemporal Nerve: This nerve runs alongside the artery in the temple area and provides sensory innervation to parts of the scalp and ear.
- Temporalis Muscle: The artery runs over this muscle, supplying its outer surface via the middle temporal artery.
Function
Blood Supply to the Scalp
One of the primary functions of the superficial temporal artery is to provide blood to the scalp, particularly in the temporal, parietal, and frontal regions. The artery’s terminal branches—the frontal and parietal branches—extend over the lateral and anterior aspects of the scalp, ensuring that the skin, hair follicles, and subcutaneous tissues receive an adequate supply of oxygen and nutrients. This blood supply is essential for maintaining healthy scalp tissue and promoting hair growth.
Nourishment of the Temporalis Muscle
The superficial temporal artery also plays a key role in nourishing the temporalis muscle, a large, fan-shaped muscle involved in mastication (chewing). Through its middle temporal branch, the artery delivers oxygenated blood to this muscle, allowing it to function effectively during jaw movements. Proper blood flow is necessary for muscle contraction and recovery after exertion, such as chewing or clenching the teeth.
Vascularization of the Parotid Gland
As the superficial temporal artery courses through the parotid gland at its origin, it contributes to the gland’s vascular supply. The parotid gland, the largest of the salivary glands, produces and secretes saliva into the mouth, aiding in digestion. A healthy blood supply provided by the superficial temporal artery helps the parotid gland maintain its function and ensures the integrity of the surrounding tissues.
Supply to Facial Structures
The transverse facial artery, a key branch of the superficial temporal artery, supplies blood to facial structures including the skin, muscles, and soft tissues of the lateral face. By nourishing the parotid gland, masseter muscle, and overlying facial skin, the artery supports the overall health and function of the face. Additionally, this artery plays a role in facial aesthetics, as it contributes to skin health and elasticity by delivering necessary nutrients.
Maintenance of Forehead and Temporal Skin Health
The superficial temporal artery’s frontal branch supplies the skin of the forehead and upper face. This ensures that the skin in these areas remains well-nourished, promoting healthy skin function, regeneration, and healing. It also contributes to the overall integrity and appearance of the forehead, helping to maintain the elasticity and vitality of the skin.
Collateral Circulation
The superficial temporal artery participates in anastomotic connections with other arteries of the face and scalp, including the supraorbital, supratrochlear, and occipital arteries. These connections form an extensive collateral circulation network that is crucial for maintaining blood flow in cases of vessel occlusion or injury. Collateral circulation ensures that the scalp and facial tissues continue to receive an adequate blood supply, even if the primary arterial route is compromised. This redundancy in the vascular system helps protect against ischemia and tissue damage.
Role in Thermoregulation
As part of its blood supply to the scalp and face, the superficial temporal artery plays a role in thermoregulation. The scalp has a rich vascular network that helps dissipate heat from the body. By adjusting blood flow to the surface of the scalp, the superficial temporal artery aids in regulating body temperature. Increased blood flow allows for heat to be released through the skin, while reduced flow conserves heat, making this function essential in maintaining homeostasis.
Support for Facial Movements and Expression
The blood supply provided by the superficial temporal artery and its branches supports the muscles involved in facial expression, such as the zygomatic muscles and others in the lateral face. By delivering oxygen and nutrients to these muscles, the artery ensures they can function properly in creating expressions such as smiling, frowning, or raising the eyebrows. The artery also supports the function of the skin and soft tissues involved in these expressions.
Clinical Significance
The superficial temporal artery has significant clinical relevance due to its location and role in vascularizing the scalp, face, and parotid region.
Temporal Arteritis (Giant Cell Arteritis)
One of the most important conditions associated with the superficial temporal artery is temporal arteritis, or giant cell arteritis. This is an inflammatory disease of large and medium-sized arteries, commonly affecting the superficial temporal artery. Symptoms include severe headaches, scalp tenderness, jaw claudication, and vision disturbances. Early diagnosis and treatment are crucial to prevent complications such as vision loss.
Scalp Surgery and Cosmetic Procedures
The superficial temporal artery is often encountered in cosmetic and reconstructive surgeries, particularly those involving the scalp, forehead, and temporal region. Surgeons must take care to avoid damaging the artery to prevent excessive bleeding and ensure proper healing. Its superficial course also makes it accessible for flap procedures in reconstructive surgery.
Headaches and Migraine
The superficial temporal artery is sometimes implicated in certain types of headaches, including migraines and tension headaches. Pulsation or tenderness of the artery can occur during these conditions, and in some cases, procedures like artery ligation or injections near the artery are considered for treatment.
Trauma and Vascular Surgery
Due to its superficial location, the superficial temporal artery is susceptible to trauma, such as lacerations or blunt injury. In cases of injury, bleeding from this artery may require surgical intervention or ligation to prevent hemorrhage. It is also commonly used as an access point for diagnostic angiography and in bypass procedures for vascular conditions affecting the brain.
