The transverse facial artery arises from the superficial temporal artery within the substance of the parotid gland, passes through the gland, and crosses the face in a transverse direction. Lying on the superficial surface of the masseter muscle, it is between the zygomatic arch and the parotid duct.
Branches of the maxillary artery
The maxillary artery, the larger of the two terminal branches of the external carotid artery, gives off several small branches which contribute to the arterial supply to the face:
The infra-orbital artery enters the face through the infra-orbital foramen and supplies the lower eyelid, upper lip, and the area between these structures.
The buccal artery enters the face on the superficial surface of the buccinator muscle and supplies structures in this area.
The mental artery enters the face through the mental foramen and supplies the chin.
Branches of the ophthalmic artery
Three small arteries from the internal carotid artery also contribute to the arterial supply of the face. These vessels arise from the ophthalmic artery, a branch of the internal carotid artery, after the ophthalmic artery enters the orbit:
The zygomaticofacial and zygomaticotemporal arteries come from the lacrimal branch of the ophthalmic artery (Fig. 8.67), enter the face through the zygomaticofacial and zygomaticotemporal foramina, and supply the area of the face over the zygomatic bone.
The dorsal nasal artery, a terminal branch of the ophthalmic artery, exits the orbit in the medial corner, and supplies the dorsum of the nose.
The supraorbital and supratrochlear arteries supply the anterior scalp.
The facial vein is the major vein draining the face (Fig. 8.67). Its point of origin is near the medial corner of the orbit as the supratrochlear and supra-orbital veins come together to form the angular vein. This vein becomes the facial vein as it proceeds inferiorly and assumes a position just posterior to the facial artery. The facial vein descends across the face with the facial artery until it reaches the inferior border of the mandible. Here the artery and vein part company and the facial vein passes superficial to the submandibular gland to enter the internal jugular vein.
Throughout its course the facial vein receives tributaries from veins draining the eyelids, external nose, lips, cheek, and chin that accompany the various branches of the facial artery.
The transverse facial vein is a small vein that accompanies the transverse facial artery in its journey across the face (Fig. 8.67). It empties into the superficial temporal vein within the substance of the parotid gland.
As it crosses the face, the facial vein has numerous connections with venous channels passing into deeper regions of the head (Fig. 8.68): near the medial corner of the orbit, it communicates with ophthalmic veins; in the area of the cheek it communicates with veins passing into the infra-orbital foramen; it also communicates with veins passing into deeper regions of the face (i.e., the deep facial vein connecting with the pterygoid plexus of veins).
All these venous channels have interconnections with the intracranial cavernous sinus through emissary veins that connect intracranial with extracranial veins. There are no valves in the facial vein or any other venous channels in the head, so blood can move in any direction. Because of the interconnections between the veins, infections of the face, primarily above the mouth (i.e., the “danger area”) should be handled with great care to prevent the dissemination of infectious material in an intracranial direction.