3. Vasculature & Lymphatics of the Head & Neck

Arteries of the Head & Neck: Overview & Arteria Subclavia

Fig. 3.1 Overview of the arteries of the head and neck

Left lateral view. The left arteria carotis communis arises from the arcus aortae; the right arteria carotis communis from the truncus brachiocephalicus. Each arteria carotis communis divides into an arteria carotis interna and an arteria carotis externa at the bifurcatio carotidis, which is at the approximate level of the fourth cervical vertebra. The glomus caroticum is located at the bifurcatio carotidis. It contains the chemoreceptors that respond to oxygen deficiency in the blood (hypoxia) and to changes in pH (both are important in the regulation of breathing). The arteria carotis interna does not branch further before entering the skull, where it mainly supplies blood to the brain. It also gives off branches that supply areas of the facial skeleton that emerge from the cranium.

Fig. 3.2 Arteria subclavia and its branches

Anterior view. The arteria subclavia distributes a number of branches to structures located at the base of the neck and in the region of the apertura thoracis superior. Note that the branches of the arteria subclavia may arise in a variable sequence. After emerging from the apertura thoracis superior, the arteria subclavia passes through the interscalene space (between the musculus scalenus anterior and musculus scalenus medius) and on into the axilla as the arteria axillaris. Each arteria vertebralis arises from the posterior aspect of the arteria subclavia on each side and ascends through the foramina in the processus transversi of the vertebrae cervicales (C6–C1). After entering the skull through the foramen magnum, the arteriae vertebrales unite to form the arteria basilaris and contribute to the formation of both the arteriae cerebri, forming anastomoses (circulus arteriosus cerebri) that have major clinical importance in supplying the blood to the brain.

Arteriae Carotides Externa & Interna: Overview

Fig. 3.3 Arteries of the head

Left lateral view. The arteria carotis communis divides into the arteria carotis interna (purple) and the arteria carotis externa (gray) at the bifurcatio carotidis (at the level of the C4 vertebra, between the cartilago thyroidea and os hyoideum). The arteria carotis externa divides into eight major branches that supply the scalp, face, and structures of the head and neck. These eight branches can be arranged into four groups: anterior (red), medial (blue), posterior (green), and terminal (yellow). The arteria carotis interna does not branch before entering the skull. It gives off branches within the cavitas cranii.

The arteria ophthalmica branch of the arteria carotis interna provides branches that will anastomose with branches of the arteria facialis on the face (see Fig. 3.12).

A carotid bruit is a noise (“swooshing” sound) caused by turbulent blood flow in the arteria carotis. It is suggestive of arteria carotis stenosis (narrowing) due to atherosclerosis (hardening of the arteries). It is best heard with the stethoscope placed over the bifurcatio carotidis (at the upper border of the cartilago thyroidea). Surgical intervention is necessary for those with >60% lumen stenosis, which is indicated by imaging.

Table 3.2 Branches of the arteriae carotides externa and interna

Artery	Branch	Regions supplied
Arteria carotis externa*(gray)	Arteria thyroidea superior (red)	Larynx, glandula thyroidea, pharynx, musculus sternocleidomastoideus
	Arteria pharyngea ascendens (blue)	Muscles of the pharyngeal wall, mucosa of the auris media, dura, fossa cranii posterior
	Arteria lingualis (red)	Floor of the cavitas oris, lingua, glandula sublingualis, epiglottis, musculi suprahyoidei
	Arteria facialis (red)	Superficial face, glandula submandibularis, pharyngeal wall, palatum molle, tonsillae palatinae, venter anterior musculi digastrici, musculus mylohyoideus, nose and septum nasi
	Arteria occipitalis (green)	Scalp in occipital region; posterior neck muscles
	Arteria auricularis posterior (green)	Cavitas tympanica, posterior auricula, glandula parotida, posterior scalp
	Arteria maxillaris (yellow)	Mandibular and maxillary dentition, muscles of mastication, posteromedial facial skeleton, cavitas nasi, face, and meninges
	Arteria temporalis superficialis (yellow)	Scalp of forehead and vertex, soft tissue below arcus zygomaticus, musculus masseter, glandula parotidea, external orbital wall, musculus orbicularis oculi
Arteria carotis interna (purple)	Arteriae caroticotympanicae	Tuba auditiva and anterior wall of cavitas tympani
	Arteriae caroticotympanicae	Anastomosis with arteria carotis externa
	Arteriae hypophysiales superior and inferior	Hypophysis
	Ramus sinus cavernosi	Anastomosis with arteria carotis externa
	Ramus meningeus	Meninges of the fossa cranii anterior
	Rami ganglionares trigeminales	Ganglion trigeminale
	Arteria ophthalmica	Nervus opticus, chiasma opticum, tractus opticus, retina, extraocular muscles, palpebrae, glandula lacrimalis, forehead, cellulae ethmoidales, sinus frontalis, lateral nasal wall, dorsum nasi, and meninges
	Arteria cerebri anterior	Medial aspect of lobi frontalis and parietalis, corpus callosum
	Arteria cerebri media	Lobi frontalis, parietalis, and temporalis
	Arteria communicans posterior	Anastomosis with arteria cerebri as part of circulus arteriosus cerebri
	Arteria communicans posterior	Plexus choroideus of the ventriculi lateralis and tertius, chiasma opticum and tractus opticus, capsula interna, corpus geniculatum laterale, globus pallidus, nucleus caudatus, hippocampus, amygdala, substantia nigra, nucleus ruber, crus cerebelli
* Anterior branches of arteria carotis externa are red; medial branches are blue; posterior branches are green; and terminal branches are yellow ** There is also an arteria canalis pterygoidei from the 3rd part of the arteria maxillaris.

Arteria Carotis Externa: Anterior & Medial Branches

Fig. 3.4 Arteriae thyroidea superior and pharyngea ascendens

Left lateral view. The arteria thyroidea superior is typically the first branch to arise from the arteria carotis externa. One of the anterior branches, it supplies the larynx (via the arteria laryngea superior) and glandula thyroidea. The arteria pharyngea ascendens springs from the medial side of the arteria carotis externa, usually arising above the level of the arteria thyroidea superior.

Fig. 3.5 Arteria lingualis and its branches

Left lateral view. The arteria lingualis is the second anterior branch of the arteria carotis externa. It has a relatively large caliber, providing the tongue and cavitas oris with its rich blood supply. It also gives off branches to the tonsillae palatinae.

Table 3.3 Branches of the arteriae thyroidea superior, lingualis, and pharyngea ascendens

Branch of arteria carotis externa	Further branches	Region supplied
Arteria thyroidea superior	Arteria laryngea superior	Larynx
	Rami glandulares	Glandula thyroidea
	Ramus sternocleidomastoideus	Musculus sternocleidomastoideus
	Muscular branches	Pharynx
	Ramus infrahyoideus	Region of membrana thyrohyoidea
	Ramus cricothyroideus	Region of the ligamentum cricothyroideum
Arteria lingualis	Ramus suprahyoideus	Musculi suprahyoidei
	Rami dorsales linguae	Base of lingua, epiglottis
	Arteria sublingualis	Glandula sublingualis, lingua, floor of the cavitas oris
	Arteria profunda linguae	Lingua
Arteria pharyngea ascendens	Rami pharyngeales	Muscles of the pharyngeal wall
	Arteria tympanica inferior	Mucosa of auris media
	Arteria meningea posterior	Dura; fossa cranii posterior

Fig. 3.6 Arteria facialis and its branches

Left lateral view. The arteria facialis has four cervical and four facial branches. The four cervical branches (arteria palatina ascendens, ramus tonsillaris, rami glandulares, and arteria submentalis) arise in the neck before the arteria facialis crosses the mandibula to reach the face. The four facial branches (arteriae labiales inferior and superior, ramus lateralis nasi, and arteria angularis) supply the superficial face. Branches of the arteria facialis anastomose with branches of the arteria carotis interna as well as other branches derived from the arteria carotis externa (see Fig 3.12, p. 59).

Table 3.4 Branches of the arteria facialis

Course: The arteria facialis arises from the arteria carotis externa in the trigonum caroticum of the neck. It then passes superiorly immediately deep to the venter posterior musculi digastrici and the musculus stylohyoideus. It runs along the glandula submandibularis then loops under and over the corpus mandibulae at the anterior border of the musculus masseter. It then runs anterosuperiorly across the cheek to the angulus oris and then continues superiorly along the side of the nose. It terminates as the arteria angularis along the medial aspect of the orbita. At its termination, the arteria angularis anastomoses with the arteria dorsalis nasi.
Branch	Region supplied
Cervical branches
Arteria palatina ascendens	Pharyngeal wall, palatum molle, tuba auditiva, tonsillae palatinae, pharynx
Ramus tonsillaris	Tonsillae palatinae and pars oralis pharyngis
Rami glandulares	Glandula submandibularis
Arteria submentalis	Venter anterior musculi digastrici, musculus mylohyoideus, glandula submandibularis
Facial branches
Arteria labialis inferior	Labium inferius
Arteria labialis superior	Labium superius; septum nasi (via ramus septi nasi)
Ramus lateralis nasi	Dorsum nasi
Arteria angularis	Radix nasi

Arteria Carotis Externa: Posterior Branches

Fig. 3.7 Branches of the arteria occipitalis

The arteria occipitalis generally arises from the arteria carotis externa, just opposite the origin of the arteria facialis and just inferior to the venter posterior musculi digastrici (not shown). The artery passes posteriorly and near its origin is crossed laterally by the nervus hypoglossus (not shown). In its course to the posterior of the occiput, the arteria occipitalis passes lateral to the arteria carotis interna (at the same time that it is passing lateral to both the vena jugularis interna and cranial nerves CN X and CN XI--not shown). At the base of the skull, the arteria occipitalis passes medial to the processus mastoideus, travelling in the sulcus arteria occipitalis. Branches of the arteria occipitalis anastomose with branches of both the arteriae auricularis posterior and temporalis superficialis. On the posterior aspect of the cranium, the artery converges with the nervus occipitalis major (not shown). The arteria occipitalis gives rise to eight named branches (see Table 3.5).

Fig. 3.8 Branches of the arteria auricularis posterior

The arteria auricularis posterior arises from the arteria carotis externa as the last branch before the origin of its two terminal branches (arteriae maxillaris and temporalis superficialis). It arises superior to the venter posterior musculi digastrici. In its course the arteria auricularis posterior travels deep to the glandula parotidea and ascends along the lateral aspect of the processus styloideus of the os temporale. The artery then passes superiorly between the processus mastoideus and the posterior aspect of the auricula. It gives rise to 5 named branches (see Table 3.5).

Table 3.5 Branches of the arteriae occipitalis and auricularis posterior

Branch	Further branches	Region supplied
Arteria occipitalis	Muscular branch	Regional muscles including venter posterior musculi digastrici and musculus stylohyoideus
	Rami sternocleidomastoidei	Musculus sternocleidomastoideus
	Ramus descendens	Posterior neck muscles
	Ramus meningeus	Structures internal and external to foramen jugulare
	Rami mastoidei	Cellulae mastoideae and dura
	Ramus auricularis	Auricula (medial side)
	Ramus occipitalis	Scalp of occipital region
	Arteria stylomastoidea*	Nervus facialis in canalis nervi facialis; cavitas tympani
Arteria auricularis posterior	Arteria stylomastoidea*	Nervus facialis in canalis nervi facialis; cavitas tympani
	Ramus occipitalis	Occiput
	Muscular branches	Venter posterior musculi digastrici and musculus stylohyoideus
	Ramus parotideus	Glandula parotidea
	Ramus auricularis	Posterior side of auricula
* The arteria stylomastoidea has a variable origin; it arises from the arteria occipitalis two thirds of the time and the arteria auricularis posterior one third of the time.

Arteria Carotis Externa: Terminal Branches (I)

The two terminal branches of the arteria carotis externa are the arteria maxillaris and the arteria temporalis superficialis. They divide within the substance of the glandula parotidea. The arteria maxillaris is the largest of the two terminal branches. It supplies the maxilla and mandibula (including the teeth), the muscles of mastication, the palatum, the nose, and the dura covering the brain.

Fig. 3.9 Arteria maxillaris

Left lateral view. A Schematic. B Course of the arteria maxillaris. The maxillaris can be divided into three parts: mandibular (blue), pterygoid (green), and pterygopalatine (yellow). See Table 3.6.

Fig. 3.10 Arteria meningea media

Medial view of right arteria meningea media. The arteria meningea media arises from the mandibular portion of the arteria maxillaris. It passes through the foramen spinosum into the fossa cranii media. Despite its name, it supplies blood not just to the meninges, but also to the overlying calvaria. Rupture of the arteria meningea media by head trauma results in an epidural hematoma (see Fig. 4.58, p. 103).

Table 3.6 Branches of the arteria maxillaris

Branch	Course	Distribution
Mandibular part (blue): Also known as the bony part or 1st part, this portion runs medial to the collum mandibulae and gives off 5 major branches, all of which enter bone.
Arteria alveolaris inferior	Gives off a lingual and a ramus mylohyoideus before entering the foramen mandibulae to travel along the canalis mandibulae; it splits into 2 terminal branches (incisive and ramus mentalis)	Dentes molares and premolares mandibulares with associated gingiva, mandibula
	• Lingual branch	Lingual mucous membrane
	• Ramus mylohyoideus	Musculus mylohyoideus
	• Incisive branch	Dentes incisivi mandibulares
	• Ramus mentalis	Chin
Arteria tympanica anterior	Runs through the Fissura petrotympanica along with the chorda tympani	Auris media
Arteria auricularis profunda	Travels through the wall of the meatus acusticus externalis	Lateral membrana tympanica, skin of meatus acusticus externus
	• Branch to articulatio temporomandibularis	Articulatio temporomandibularis
Arteria meningea media	Runs through the foramen spinosum to the fossa cranii media	Bones of the cranial vault, dura of fossae cranii anterior and mediae
Ramus accessorius arteriae meningeae mediae	Runs through the foramen ovale to the fossa cranii media	Musculi pterygoidei medialis and laterales, tensor veli palatini, sphenoid bone, dura, ganglion trigeminale
Pterygoid part (green): Also known as the muscular part or 2nd part, this portion runs between the musculi temporalis and musculi. It gives off 5 major branches, all of which supply muscle.
Arteria masseterica	Runs through the incisura mandibulae (notch)	Musculus masseter, articulatio temporomandibularis
Rami temporales profundae	Consist of anterior, middle, and posterior branches, which course deep to the musculus temporalis	Musculus temporalis
Rami pterygoidei (lateral part)	Runs directly to the musculus pterygoideus lateralis	Musculus pterygoideus lateralis
Rami pterygoidei (medial part)	Runs directly to the musculus pterygoideus medialis	Musculus pterygoideus medialis
Arteria buccalis	Accompanies the nervus buccalis	Buccal mucosa and skin, musculus buccinator
Pterygopalatine part or 3rd part (yellow): This portion runs through the fissura pterygomaxillaris to enter the fossa pterygopalatinum. It gives off 6 major branches, which accompany the branches of the nervus maxillaris (CN V2).*
Arteria alveolaris superior posterior	Runs through the fissura pterygomaxillaris; may arise from the arteria infraorbitalis	Dentes molares and premolares maxillares, with associated gingiva; sinus maxillaris
Arteria infraorbitalis	Runs through the fissura orbitalis inferior into the orbita, where it runs along the sulcus infraorbitalis and canalis infraorbitalis, exiting onto the face via the foramen infraorbitale	Cheek, upper lip, nose, lower eyelid
	• Arteriae alveolares superior anterior and middle superior alveolar aa.	Dentes maxillares and sinus maxillaris
Arteria palatina descendens	• Arteria palatina major: runs via the canalis palatinus major; in the canal it gives off several arteriae palatinae minores; continues through foramen palatinum majus onto palatum durum	Roof of palatum durum, cavitas nasi (meatus inferior), maxillary gingiva
	• Arteriae palatinae minores: runs via the foramen palatinum minus	Palatum molle
	• Anastomosing branch: runs via the canalis incisivus; joins with the arteria sphenopalatina	Septum nasi
Arteria sphenopalatina	Runs via the foramen sphenopalatinum to the cavitas nasi; gives off arteriae nasales posteriores laterales, then travels to the septum nasi, where it terminates as rami septales posteriores
	• Arteriae nasales posteriores laterales: anastomose with the arteriae ethmoidales and nasal branches of the arteria palatina major	Nasal air sinuses (sinus frontalis, sinus maxillaris, cellulae ethmoidales, and sinus sphenoidalis)
	• Rami septales posteriores: anastomose with the arteriae ethmoidales on the septum nasi	Conchae nasi and septum nasi
Arteria canalis pterygoidei	Runs through the canalis pterygoideus	Tuba auditiva, cavitas tympani, upper pharynx
Rami pharyngei	Runs through the canalis palatovaginalis	Pars nasalis pharyngis, sinus sphenoidalis, and tuba auditiva; mucosa of cavitas nasi
*All branches are named for the nerve they travel with except for the arteria sphenopalatina, which travels with the nervus nasopalatinus.

Arteria Carotis Externa: Terminal Branches (II) & Anastomoses

Fig. 3.11 Arteria temporalis superficialis

Left lateral view. The arteria temporalis super-ficialis is the second of the two terminal branches of the arteria carotis externa. Particularly in elderly or cachectic patients, the often tortuous course of the frontal branch of this vessel can be easily traced across the temple. Temporal arteritis (giant cell arteritis, cranial arteritis) is an inflammatory condition affecting the medium-sized arteries that supply the temple region, scalp, eyes, and nervi optici. The average age of onset of this condition is 70 years and it affects women twice as commonly as men. Symptoms may begin as general malaise and progress rapidly to headaches, tenderness of the scalp, severe pain in the temple region, transient blurred vision, diplopia (double vision), ptosis (drooping eyelid), neck pain, and jaw claudication (pain on jaw manipulation, e.g., during eating, due to ischemia of the musculus masseter). It is diagnosed by blood tests that indicate an inflammatory process is ongoing and by biopsy of the arteria temporalis superficialis (definitive test). If not treated promptly (usually before biopsy results confirm the condition), then it may cause painless loss of vision in the affected eye that is usually permanent. Having temporal arteritis also increases the risk of stroke and aortic aneurysm. Treatment is with corticosteroids, often long-term.

Table 3.7 Branches of the arteria temporalis superficialis

Branch	Further branches	Region supplied
Arteria temporalis superficialis	Arteria transversa faciei	Soft tissues below arcus zygomaticus, glandula parotidea, musculus masseter
	Rami auriculares anteriores	Meatus acusticus externa, anterior area of auricula
	Arteria temporalis media	Musculus temporalis
	Arteria zygomaticoorbitalis	Lateral external orbital wall and musculus orbicularis oculi
	Rami frontales	Scalp of forehead
	Rami parietales	Scalp of vertex

Fig. 3.12 Anastomoses of the arteriae carotides externa and interna

Branches of the arteria carotis externa (e.g., arteria facialis [red], arteria temporalis superficialis [yellow], and arteriae infraorbitales [yellow]) and the arteria carotis interna (e.g., arteriae dorsalis nasi and supraorbitalis [purple]) anastomose in certain facial regions to ensure blood flow to the face and head. Anastomoses occur between the arteria angularis and arteria dorsalis nasi and between the arteria temporalis superficialis and arteria supraorbitalis. Due to the extensive arterial anastomoses, facial injuries tend to bleed profusely but also heal quickly.

Fig. 3.13 Arteria infraorbitalis

Left lateral view. The arteria infraorbitalis arises from the pterygopalatine part of the arteria maxillaris (a terminal branch of the arteria carotis externa), and the arteria supraorbitalis (not shown) arises from the arteria carotis interna (via the arteria ophthalmica). These vessels therefore provide a path for potential anastomosis between the arteriae carotides interna and externa on the face.

Fig. 3.14 Arteria sphenopalatina

Medial view of right nasal wall and right arteria sphenopalatina. The arteria sphenopalatina enters the cavitas nasi through the foramen sphenopalatinum. The anterior portion of the septum nasi contains a highly vascularized region (Kiesselbach’s area), which is supplied by both the rami septales posteriores of the arteria sphenopalatina (arteria carotis externa) and the rami septales anteriores of the arteria ethmoidalis anterior (arteria carotis interna via arteria ophthalmica). When severe nasopharyngeal bleeding occurs, it may be necessary to ligate the arteria maxillaris in the fossa pterygopalatina.

Arteria Carotis Interna

Fig. 3.15 Overview of the arteria carotis interna

The arteria carotis interna branches from the arteria carotis communis at the level of the bifurcatio carotidis (C4 vertebral level). Its extracranial part gives off no branches. The internal part has four anatomical parts that supply blood to the truncus encephali and encephalon (see Fig 3.16).

Fig. 3.16 Subdivisions of the arteria carotis interna

Anatomical segments of the arteria carotis interna and their branches. The Arteria carotis interna is distributed chiefly to the brain but also supplies extracerebral regions of the head. It consists of four parts (listed from bottom to top):

• Pars cervicalis

• Pars petrosa

• Pars cavernosa

• Pars cerebralis

The pars petrosa of the arteria carotis interna (traversing the canalis caroticus) and the pars cavernosa (traversing the sinus cavernosus) have a role in supplying extracerebral structures of the head. They give off additional small branches that supply local structures and are usually named for the areas they supply. Of the branches not supplying the encephalon, of special importance is the arteria ophthalmica, which arises from the pars cerebralis of the arteria carotis interna. Note: The arteria ophthalmica forms an anastomosis with the arteria canalis pterygoidei derived from the arteria maxillaris.

Fig. 3.17 Blood supply to the encephalon

A Schematic of circulus arteriosus cerebri in situ. B Schematic of isolated circulus arteriosus cerebri.

The encephalon is supplied by four arteries that leave the root of the neck separately, the left and right arteria carotis interna and the left and right arteriae vertebrales. However, the arteriae vertebrales converge to form the arteria basilaris and so only three arteries reach the base of the brain, where they form the circulus arteriosus cerebri. The circulus arteriosus cerebri is a means by which the encephalon can receive blood when one or more of its major arterial contributors becomes narrowed or blocked, for example, by an embolus, possibly preventing ischemic stroke.

Table 3.8 Contribution of the arteria carotis interna to the blood supply of the eye, nose, face, and surrounding areas

Course: The arteria ophthalmica branches from the arteria carotis interna (ICA) just after the ICA passes through the sinus cavernosus. It runs along the medial side of the processus clinoideus anterior passing anteriorly through the canalis opticus with the nervus opticus. It then courses in the medial wall of the orbita. The two terminal branches of the arteria ophthalmica are the arteria dorsalis nasi and supratrochlearis.
Origin	Artery	Region supplied
Arteria ophthalmica (branch of arteria carotis interna)	Ocular branches
	Arteria centralis retinae	Retina
	Arteriae ciliares anteriores	Bulbus oculi
	Arteriae ciliares posteriores longae and breves	Bulbus oculi
	Orbital branches
	Arteria lacrimalis	Glandulae lacrimales, palpebrae, and conjunctiva
	Arteriae musculares	Extraocular muscles
	Arteriae palpebrales mediales	Palpebrae
	Arteria ethmoidalis posterior	Cellulae ethmoidales, posterosuperior septum nasi, part of sinus sphenoidalis and meninges
	Arteria ethmoidalis posterior	Cellulae ethmoidales, anterosuperior septum nasi, lateral nasal wall, and fossa cranii anterior
	Arteria supratrochlearis	Muscles and skin of the medial forehead, and sinus frontalis
	Arteria supraorbitalis	Muscles and skin of the forehead, and sinus frontalis
	Ramus meningeus	Fossa cranii media
	Arteria dorsalis nasi	Region along the bridge of the nose

Veins of the Head and Neck: Overview

Fig. 3.18 Veins of the head and neck

Left lateral view. The principal vein of the head and neck is the vena jugularis interna. This drains blood from both the exterior and the interior of the skull (including the brain) in addition to receiving venous blood from the neck. It receives blood from the common facial vein (formed by the union of the vena facialis and the anterior division of the vena retromandibularis), the venae lingualis, thyroidea superior, and thyroideae mediae, and the sinus petrosus inferior. Enclosed in the vagina carotica, the vena jugularis interna descends from the foramen jugulare to its union with the vena subclavia to form the vena brachiocephalica. The vena jugularis externa receives blood from the posterior division of the vena retromandibularis and the vena auricularis posterior. The vena occipitalis normally drains to the vena cervicalis profunda. The vena subclavia in the thorax can be catheterized in acutely ill or chronically ill patients to provide a fast and stable route for administering medication, fluids, and nutrition, and for measuring central oxygen saturation and central venous pressure (to quantify their fluid status). This is called central venous catheterization or a “central line.” Other large veins in the neck (e.g., the vena jugularis interna), thorax (e.g., the vena axillaris), or the groin (e.g., the vena femoralis) can also be catheterized in this way.

Fig. 3.19 Veins of the head: overview

The superficial veins of the head communicate with each other and with the sinus durae matris via the deep veins of the head (plexus pterygoideus and sinus cavernosus). The plexus pterygoideus connects the vena facialis and the vena retromandibularis (via the vena profunda faciei and vena maxillaris, respectively). The sinus cavernosus connects the vena facialis to the sinus sigmoideus (via the venae ophthalmicae and the sinus petrosi, respectively).

Sinus cavernosus thrombosis is the formation of a thrombus (blood clot) in the sinus cavernosi. It usually occurs secondary to an infection in the nasal sinuses, teeth, ears, eyes, or the skin of the face. The infective organism is typically staphylococcus aureus, but it can also be caused by streptococci, pneumococci, and fungi. Signs and symptoms include headache, eye pain, exophthalmos (bulging eyeball), ptosis (drooping eyelid), vision loss, sluggish pupillary responses, and limitation of movement of the eye due to paralysis of the nervi oculomotorius, trochlearis and abducens. It may progress to meningitis or sepsis.

Superficial Veins of the Head

Fig. 3.20 Venous drainage to the vena facialis communis

The vena facialis communis is formed by the union of the vena facialis and the anterior division of the vena retromandibularis. These tributaries combine to drain much of the face, eye, and cavitas oris (see Table 3.10). The vena facialis communis empties into the vena jugularis interna. Note: The course of veins is highly variable.

Table 3.10 Tributaries of the vena facialis communis

Course: tributaries of the vena facialis communis course parallel to the branches of the arteria maxillaris
Tributary	Further tributaries	Region drained
Vena facialis	Vena angularis*	Anterior scalp, forehead, upper and lower palpebrae, conjunctiva, root of the nose, sinus cavernosus (via communication with vena ophthalmica)
	Vena nasalis externa	External nose
	Vena labialis superior	Labium superius
	Vena labialis inferior	Labium inferius
	Vena profunda faciei (from plexus pterygoideus)	Contributes to drainage from plexus pterygoideus (see vena maxillaris below)
	Venae parotideae	Parotid region
	Vena palatina externa	Palatum molle and tonsillae
	Vena submentalis	Mylohyoid region
Vena retromandibularis, anterior division	Vena maxillaris (from plexus pterygoideus)	Orbita and oculus, muscles of mastication, musculi faciei, buccal mucosa and skin, palatum durum, palatum molle, teeth and their associated gingivae, glandulae submandibulares, sublinguales, and parotideae, articulatio temporomandibularis, chin, sinus paranasales (frontalis, maxillaris, ethmoidalis, and sphenoidalis), conchae nasi, septum nasi, meatus acusticus externus, membrana tympanica
	Vena temporalis superficialis	Anterior auricula, temple region, and scalp
* The vena angularis is formed by the confluence of the venae supratrochlearis and subraorbitalis

Fig. 3.21 Venous drainage to the vena jugularis externa

The vena jugularis externa receives blood from the vena auricularis posterior, the posterior division of the vena retromandibularis, the posterior vena jugularis externa, the vena transversa cervicis, and the vena suprascapularis. These tributaries combine to drain the face and superficial neck (see Table 3.11). The vena jugularis externa drains into the vena subclavia.

Table 3.11 Tributaries of the vena jugularis externa

Course: Arises at the confluence of vena auricularis posterior and the posterior division of the vena retromandibularis within the substance of the glandula parotidea, at the level of the angulus mandibulae. It travels inferiorly within superficial fascia cervicalis to drain into the vena subclavia.
Tributary	Further tributaries	Region drained
Vena auricularis posterior		Posterior auricula, meatus acusticus externus, membrana tympanica, posterior scalp, glandula parotidea
Vena retromandibularis, posterior division	Vena maxillaris	Orbita and oculus, muscles of mastication, musculi faciei, buccal mucosa and skin, palatum durum, palatum molle, teeth and their associated gingivae, glandulae submandibularis, sublingualis, and parotidea, articulatio temporomandibularis, chin, sinus paranasales (frontalis, maxillaris, ethmoidalis, and sphenoidalis), conchae nasi, septum nasi, meatus acusticus internus, membrana tympanica
	Vena temporalis superficialis	Anterior auricula, superficial face
Posterior vena jugularis externa		Skin and superficial muscles in the upper and back part of the neck
Vena transversa cervicis		Musculus trapezius and surrounding tissue
Vena suprascapularis		Musculi supraspinatus and infraspinatus; shoulder joint
Vena jugularis anterior		Superficial parts of the anterior neck

Deep Veins of the Head

Fig. 3.22 Venous drainage of the head

The superficial veins of the head have extensive connections with the deep veins of the head and the sinus durae matris. The meninges and encephalon are drained by the sinus durae matris, which lie within the skull. Venae emissariae connect the superficial veins of the skull directly to the sinus durae matris. In addition, the deep veins of the head (e.g., plexus pterygoideus) are intermediaries between the superficial veins of the face and the sinus venosi durae matris.

Table 3.12 Venous anastomoses as portals of infection

The extracranial veins of the head are connected to the deep veins and sinus durae matris. Patients who sustain midfacial fractures may bleed profusely due to the extensive venous anastomoses. Because the veins are generally valveless, extracranial bacteria may migrate to the deep veins, causing infections (e.g., bacteria from boils on the upper lip or nose may enter the vena angularis and travel to the sinus cavernosus). Bacteria in the sinus cavernosus may cause thrombosis.
Extracranial vein	Connecting vein	Venous sinus
Vena angularis	Vena ophthalmica superior	Sinus cavernosus
Venae of tonsilla palatina	Plexus pterygoideus, vena ophthalmica inferior
Vena temporalis superficialis	Vena emissaria parietalis	Sinus sagittalis superior
Vena occipitalis	Vena emissaria occipitalis	Sinus transversus, confluens sinuum
Vena auricularis posterior	Vena emissaria mastoidea	Sinus sigmoideus
Plexus venosus vertebralis externus	Vena emissaria mastoidea

Fig. 3.23 Deep veins of the head

Left lateral view. The plexus pterygoideus is a venous network situated behind the ramus mandibulae and embedded in the musculi pterygoidei. Because the veins of the face have no valves (small valves may be present but are generally nonfunctional), the movement of the musculi pterygoidei forces blood from the plexus pterygoideus into the venae jugulares. The plexus pterygoideus is linked to the vena facialis via the vena profunda faciei and to the vena retromandibularis via the vena maxillaris. The plexus is also linked to the sinus cavernosus via the vena emissaria. The sinus cavernosus receives blood from the venae ophthalmicae superior and inferior.

Fig. 3.24 Veins of the occiput

Posterior view. The sinus durae matris are the series of venous channels that drain the encephalon. The superficial veins of the occiput communicate with the sinus durae matris by way of the venae emissariae. The venae emissariae enter a similarly named foramen to communicate with the sinus durae matris.

Lymphatics of the Head & Neck (I)

A distinction is made between regional lymph nodes, which are associated with a particular organ or region and constitute their primary filtering stations, and collecting lymph nodes, which usually receive lymph from multiple regional lymph node groups. Lymph from the head and neck region, gathered in scattered regional nodes, flows through its system of deep cervical collecting lymph nodes into the right and left trunci jugulares, each closely associated with its corresponding vena jugularis interna. The truncus jugularis on the right side drains into the ductus lymphaticus dexter, which terminates at the right jugulosubclavian junction. The truncus jugularis on the left side terminates at the ductus thoracicus, which empties into the left jugulosubclavian junction (see Fig. 12.16).

Fig. 3.25 Nodi lymphoidei cervicales superficiales

Right lateral view. Enlarged nodi lymphoidei cervicales are a common finding at physical examination. The enlargement of nodi lymphoidei cervicales may be caused by inflammation (usually a painful enlargement) or neoplasia (usually a painless enlargement) in the area drained by the nodes. The nodi lymphoidei cervicales superficiales are primary drainage locations for lymph from adjacent areas or organs.

Fig. 3.26 Nodi lymphoidei cervicales profundi

Right lateral view. The deep lymph nodes in the neck consist mainly of collecting nodes. They have major clinical importance as potential sites of metastasis from head and neck tumors. Affected nodi lymphoidei cervicales profundi may be surgically removed (neck dissection) or may be treated by regional irradiation. For this purpose, the American Academy of Otolaryngology—Head and Neck Surgery has grouped the deep cervical lymph nodes into six levels (Robbins 1991):

I	Nodi lymphoidei submentales and submandibulares
II‒IV	Deep cervical lymph nodes along the vena jugularis interna (lateral jugular lymph nodes):
	– II	Nodi lymphoidei cervicales laterales profundi superiores
	– III	Deep cervical lymph nodes (middle lateral group)
	– IV	Nodi lymphoidei cervicales laterales profundi inferiores
V	Lymph nodes in the posterior cervical triangle
VI	Nodi lymphoidei cervicales anteriores

Fig. 3.27 Directions of lymphatic drainage in the neck

Right lateral view. Understanding this pattern of lymphatic flow is critical to identifying the location of a potential cause of enlarged nodi lymphoidei cervicales. There are two main sites in the neck where the lymphatic pathways intersect:

• Jugulofacial venous junction: Lymphatics from the head pass obliquely downward to this site, where the lymph is redirected vertically downward in the neck.

• Jugulosubclavian venous junction: The main lymphatic trunk, the ductus thoracicus, terminates at this central location, where lymph collected from the left side of the head and neck region is combined with lymph draining from the rest of the body.

If only peripheral nodal groups are affected, this suggests a localized disease process. If the central groups (e.g., those at the venous junctions) are affected, this usually signifies an extensive disease process. Central lymph nodes can be obtained for diagnostic evaluation by prescalene biopsy.

Fig. 3.28 Relationship of the nodi lymphoidei cervicales to the systemic lymphatic circulation

Anterior view. The nodi lymphoidei cervicales may be involved by diseases that are not primary to the head and neck region, because lymph from the entire body is channeled to the left and right jugulosubclavian junctions (red circles). This can lead to retrograde involvement of the nodi cervicales. The ductus lymphaticus dexter terminates at the right jugulosubclavian junction, the ductus thoracicus at the left jugulosubclavian junction. Besides cranial and cervical tributaries, the lymph from nodi lymphoidei thoracis (mediastinal and tracheobronchiales) and from nodi lymphoidei abdominis and caudal lymph nodes may reach the cervical nodes by way of the ductus thoracicus. As a result, diseases in those organs may lead to cervical lymph node enlargement. For example, gastric carcinoma may metastasize to the left nodi lymphoidei supraclaviculares, producing an enlarged sentinel node that suggests an abdominal tumor. Systemic lymphomas may also spread to the nodi lymphoidei cervicales by this pathway.

Fig. 3.29 Systematic palpation of the nodi lymphoidei cervicales

The nodi lymphoidei cervicales are systematically palpated during the physical examination to ensure the detection of any enlarged nodes. Panel A shows the sequence in which the various nodal groups are successively palpated. The examiner usually palpates the nodi lymphoidei submentales and submandibulares first (B), including the angulus mandibulae (C), then proceeds along the anterior border of the musculus sternocleidomastoideus (D). The nodi lymphoidei supraclaviculares are palpated next (E), followed by the nodi lymphoidei accessorii and the nuchal group of nodes (F).

If lymph nodes are palpable, the following characteristics should be noted and described: size (<1 cm in diameter is normal), pain/tenderness (suggestive of inflammation), consistency (soft nodes suggest inflammation; firm, rubbery nodes suggest lymphoma; stony-hard nodes may be a sign of cancer), location of lymphadenopathy, and whether it is localized or generalized as this may help aid diagnosis.

Lymphatics of the Head & Neck (II)

Fig. 3.30 Auricula and meatus acusticus externus: lymphatic drainage

Right ear, oblique lateral view. The lymphatic drainage of the ear is divided into three zones, all of which drain directly or indirectly into the nodi lymphoidei cervicales profundi along the vena jugularis interna. The lower zone drains directly into the nodi lymphoidei cervicales profundi. The anterior zone first drains into the nodi lymphoidei parotidei, the posterior zone into the nodi lymphoidei mastoidei.

Fig. 3.31 Lymphatic drainage of the tongue and oral floor

A Left lateral view. B Anterior view.

The lymphatic drainage of the tongue and oral floor is mediated by nodi lymphoidei submentales and submandibulares that ultimately drain into the lymph nodes along the vena jugularis interna (A, nodi lymphoidei jugulares). Because the lymph nodes receive drainage from both the ipsilateral and contralateral sides (B), tumor cells may become widely disseminated in this region (e.g., metastatic squamous cell carcinoma, especially on the lateral border of the tongue, frequently metastasizes to the opposite side).

Table 3.13 Lymphatic drainage of the head and neck

Note: Lymphatic drainage of the cavitas oris is in bold.
Region	Node(s)	Secondary node(s)
Occipital region of the scalp and upper neck	Nodi occipitales	Nodi lymphoidei cervicales superficiales
Scalp in temporoparietal region, posterior surface of the ear, and skin in mastoid region	Nodi lymphoidei mastoidei (retroauricular)	Nodi lymphoidei cervicales superficiales and profundi
Anterior parietal region of the scalp, anterior surface of the ear, meatus acusticus externa, face, and buccal mucosa	Nodi parotidei superficiales (preauricular)	Nodi parotidei profundi and cervicales profundi
Meatus acusticus externa, tuba auditiva, auris media	Nodi parotidei profundi	Nodi cervicales profundi
Cavitas nasi, sinus paranasales, palatum durum (rarely), palatum molle, pars nasalis pharyngis, pars oralis pharyngis, and tubae auditivae	Nodi retropharyngeales	Nodi cervicales profundi
Superficial face and cheek	Buccal nodes	Nodi submandibulares
labium superius, lateral part of the labium inferius, cheek, vestibulum nasi, anterior cavitas nasi, gingivae, dentes, medial canthus, palatum durum, palatum molle, anterior pillar, anterior part of the tongue, glandulae submandibulares and sublinguales, and floor of mouth	Nodi submandibulares	Nodi cervicales profundi
Chin, middle part of the labium inferius, anterior gingivae, apex linguae, and anterior floor of mouth	Nodi submentales	Nodi submandibulares and cervicales profundi
Cavitas oris, pars oralis pharyngis, pars nasalis pharyngis, pars laryngea pharyngis, larynx, and glandula parotidea	Nodi jugulodigastrici	Nodi cervicales profundi
Submental region, head and neck above this level	Nodi juguloomohyoidei	Nodi cervicales profundi
Oesophagus, larynx, trachea, and glandula thyroidea	Juxtavisceral nodes (nodi prelaryngei, pretracheales, and paratracheales)	Nodi cervicales profundi
Skin and muscles of the anterior infrahyoid region of the neck	Nodi jugulares anteriores	Nodi cervicales profundi
Inferior part of the ear and parotid region	External jugular nodes Nodi tracheales	Nodi cervicales profundi
Lungs, upper oesophagus, part of the larynx below the plicae vocales	Nodi tracheales	Truncus bronchomediastinalis
Lateral part of the neck, anterior thoracic wall, glandula mammaria	Transverse cervical nodes	Truncus jugularis, or ductus lymphaticus dexter, or ductus thoracicus
Most of the lymph from the head and neck ultimately drains to the nodi cervicales superficiales or profundi then into the truncus jugularis. Some lymph also drains into the truncus bronchomediastinalis. These trunks both empty into either the ductus thoracicus or ductus lymphaticus dexter and into the venous system.