2. Mohamed el fiky
Blood supply of the SCALP
Arteries supplying the scalp are branches of either the external carotid artery or
the ophthalmic artery, which is a branch of the internal carotid artery.
Branches from the ophthalmic artery ( internal carotid )
• The supratrochlear and supra-orbital arteries supply the anterior and
superior aspects of the scalp. They branch from the ophthalmic artery while
it is in the orbit, continue through the orbit, and exit onto the forehead in
association with the supratrochlear and supra-orbital nerves. Like the
nerves, the arteries ascend across the forehead to supply the scalp as far
posteriorly as the vertex of the head.
supratrochlear
supra-orbital
3. Blood supply of the SCALP
Branches from the external carotid artery
Three branches of the external carotid artery supply the largest part of the scalp-
the superficial temporal, posterior auricular, and occipital arteries supply the
lateral and posterior aspects of the scalp
• the posterior auricular artery : leaves the posterior aspect of the external
carotid artery , supply an area of the scalp posterior to the ear.
• occipital artery, which ascends in a posterior direction, supply a large part of
the posterior aspect of the scalp.
• The superficial temporal artery, a terminal branch of the external carotid
artery that passes superiorly, just anterior to the ear, divides into anterior and
posterior branches, and supplies almost the entire lateral aspect of the scalp.
posterior auricular
occipital
superficial temporal
5. Venous drainage of scalp and Face
Superficial venous drainage
The external jugular and anterior jugular veins are the primary
venous channels for superficial venous drainage of the neck
External jugular veins
The external jugular : vein is formed posterior to the angle of the mandible as the posterior auricular vein and the
retromandibular vein join:
• The posterior auricular vein drains the scalp behind and above the ear.
• The retromandibular vein is formed when the superficial temporal and maxillary veins join in the substance of the parotid
gland and it descends to the angle of mandible, where it divides into an anterior and a posterior division-the posterior division
joins the posterior auricular vein to form the external jugular vein, and the anterior division joins the facial vein to form the
common facial vein, which passes deep and becomes a tributary to the internal jugular vein
Mohamed el fiky
6. Veins of the SCALP and face
Supra-trochlear
Supra-orbital
Anterior facial
Deep facial
Common facial
Internal jugular vein
Cavernous sinus
Sup. Ophtalmic vein
Superficial temporal vein
Maxillary vein
Posterior facial vein
External jugular vein
Subclavian vein
Pterygoid plexus
Emissary veins
Mohamed el fiky
7. Superficial venous drainage
The external jugular and anterior jugular veins are the primary venous channels for superficial venous drainage of the neck
External jugular veins
The external jugular : vein is formed posterior to the angle of the mandible as the posterior auricular vein and the
retromandibular vein join:
• The posterior auricular vein drains the scalp behind and above the ear.
• The retromandibular vein is formed when the superficial temporal and maxillary veins join in the substance of the parotid
gland and it descends to the angle of mandible, where it divides into an anterior and a posterior division (Fig. 8.160)-the
posterior division joins the posterior auricular vein to form the external jugular vein, and the anterior division joins the facial
vein to form the common facial vein, which passes deep and becomes a tributary to the internal jugular vein
Venous drainage of scalp and Face
Mohamed el fiky
8. Once formed, the external jugular vein passes
straight down the neck in the superficial fascia and is
superficial to the sternocleidomastoid muscle
throughout its course, crossing it diagonally as it
descends. Reaching the lower part of the neck, just
superior to the clavicle and immediately posterior to
the sternocleidomastoid muscle, the external jugular
vein pierces the investing layer of cervical fascia,
passes deep to the clavicle, and enters the
subclavian vein. Tributaries received by the external
jugular vein along its course include the posterior
external jugular vein (draining superficial areas of
the back of the neck) and the transverse cervical and
suprascapular veins (draining the posterior scapular
region). Mohamed el fiky
9. Dangerous Area of the Face
This includes the upper lip and the lower part of
the nose. It is drained by the facial vein, which
communicates with the cavernous sinus. Infections
of this area can therefore, spread in retrograde
direction and cause thrombosis of the cavernous
sinus.
Mohamed el fiky
10. The anterior jugular veins, although variable and inconsistent,
are usually described as draining the anterior aspect of the neck .
These paired venous channels, which begin as small veins, come
together at or just superior to the hyoid bone. Once formed,
each anterior jugular vein descends on either side of the midline
of the neck. Inferiorly, each anterior jugular vein pierces the
investing layer of cervical fascia to enter the subclavian vein.
Occasionally, the anterior jugular vein may enter the external
jugular vein immediately before the external jugular vein enters
the subclavian vein. Often, the right and left anterior jugular
veins communicate with each other, being connected by a
jugular venous arch in the area of the suprasternal notch.
Anterior jugular veins
Mohamed el fiky
11. External jugular vein
Course and relations :
• Begins behind the angle of mandible by the union of :
• Posterior auricular
• Posterior division of posterior facial vein.
• It descends obliquely backwards across the sternomastoid
• About 1 inch above the middle of the clavicle it pierces the
deep fascia to end in the subclavian vein.
Tributaries
• Posterior auricular vein.
• Posterior division of the posterior facial vein
• Posterior external jugular vein.
• Transverse cervical vein.
• Suprascapular vein.
• Anterior jugular veins.
Mohamed el fiky
12. NERVE supply of the SCALP
Sensory innervation of the scalp is from two major sources, cranial nerves or
cervical nerves, depending on whether it is anterior or posterior to the ears
and the vertex of the head .
The occipitofrontalis muscle is innervated by branches of the facial nerve [VII].
Anterior to the ears and the vertex
Branches of the trigeminal nerve [V] supply the scalp anterior to the ears and the vertex of the head .
These branches are:
1. Supratrochlear, (Ophthalmic )
2. Supra-orbital, (Ophthalmic )
3. Zygomaticotemporal, ( Maxillary )
4. Auriculotemporal ( Mandibular)
Mohamed el fiky
13. Nerve supply of the Face
During development a cranial nerve becomes associated with each of the pharyngeal arches. Because the face is
primarily derived from the first and second pharyngeal arches, innervation of neighboring facial structures is as
follows:
• The trigeminal nerve [V] innervates facial structures derived from the first arch.
• The facial nerve [VII] innervates facial structures derived from the second arch.
Sensory innervation
Because the face is derived developmentally from a number of structures originating from the first pharyngeal
arch, cutaneous innervation of the face is by branches of the trigeminal nerve [V]. The trigeminal nerve [V] divides
into three major divisions-the ophthalmic [V1], maxillary [V2], and mandibular [V 3] nerves-before leaving the
middle cranial fossa (Fig. 8.61). Each of these divisions passes out of the cranial cavity to innervate a part of the
face, so most of the skin covering the face is innervated solely by branches of the trigeminal nerve [V]. The
exception is a small area covering the angle and lower border of the ramus of the mandible and parts of the ear,
where the facial [VII], vagus [X], and cervical nerves contribute to the innervation. Mohamed el fiky
14. Nerve supply of the Face
Sensory innervation
The trigeminal nerve [V] divides into three major divisions-the ophthalmic [V1], maxillary [V2], and
mandibular [V 3] to innervate the face, so most of the skin covering the face is innervated solely by branches
of the trigeminal nerve [V]. The exception is a small area covering the angle and lower border of the ramus
of the mandible and parts of the ear, where the facial [VII], vagus [X], and cervical nerves contribute to the
innervation.
Mohamed el fiky
16. The ophthalmic nerve [V 1] exits the skull through the
superior orbital fissure and enters the orbit. Its branches
(Fig. 8.61) that innervate the face include:
• the supra-orbital and supratrochlear nerves, which leave
the orbit superiorly and innervate the upper eyelid,
forehead, and scalp
• the infratrochlear nerve, which exits the orbit in the
medial angle to innervate the medial half of the upper
eyelid, the skin in the area of the medial angle, and the side
of the nose;
• the lacrimal nerve, which exits the orbit in the lateral
angle to innervate the lateral half of the upper eyelid and
the skin in the area of the lateral angle; and
• the external nasal nerve, which supplies the anterior part
of the nose .
Ophthalmic nerve [V1,]
Mohamed el fiky
17. The maxillary nerve [V 2] exits the skull through the
foramen rotundum. Branches that innervate the face
include:
• Zygomaticotemporal branch, which exits the
zygomatic bone and supplies a small area of the anterior
temple above the zygomatic arch;
• Zygomaticofacial branch, which exits the zygomatic
bone and supplies a small area of skin over the
zygomatic bone; and
• infra-orbital nerve, which exits the maxilla through the
infra-orbital foramen and immediately divides into
multiple branches to supply the lower eyelid, cheek, side
of the nose, and upper lip .
Maxillary nerve [V2]
Mohamed el fiky
18. The mandibular nerve [V 3] exits the skull through the
foramen ovale. Branches (Fig. 8.62) innervating the face
include:
• the auriculotemporal nerve, which enters the face just
posterior to the temporomandibular joint, passes through
the parotid gland, and ascends just anterior to the ear to
supply the external acoustic meatus, the surface of the
tympanic membrane (eardrum), and a large area of the
temple;
• the buccal nerve, which is on the surface of the
buccinator muscle supplying the cheek; and
• the mental nerve, which exits the mandible through the
mental foramen and immediately divides into multiple
branches to supply the skin and mucous membrane of the
lower lip and skin of the chin
Mandibular nerve [V3]
Mohamed el fiky
19. Motor Nerves of the Face ( facial nerve )
• Orgin : from the pons Type : mixed nerve motor , sensory and
containing parasympathetic .
• Course in the face : after the facial nerve comes out from the
stylomastoid foramen it inter the parotid gland superficial to external
carotid artery and posterior facial vein and with in the parotid gland
the nerve gives five terminal branches .
• Branches :
• A- before it inter the parotid gland ( distal to the stylomastoid foramen
1- posterior auricular to the occiptal belly of occiptofrontalis muscle
and muscles around ear
• 2- Branch to posterior belly of digasteric and stylohyoid muscle
Mohamed el fiky
20. Course and relations of facial nerve
Intracranial (intrapetrosal) course
The nerve passes laterally with the vestibulocochlear nerve (CN VIII) to
the internal auditary meatus. At the bottom of the meatus the nerve
enters the facial bony canal where it runs laterally above the vestibule
of inner ear.
Reaching the medial wall of the middle ear, it bends sharply
backwards above the promontory (forming its genu) where the
genicular ganglion is found
It then arches downwards in the medial wall of the middle ear to reach
the stylomastoid foramen. Mohamed el fiky
I- Intracranial (intrapetrosal) course II- Extracranial course
21. Branches of facial nerve in the middle ear :
1. Greater petrosal nerve 2. Nerve to stapaedius 3. Chorda tympan
Mohamed el fiky
22. II- Extracranial course
Branches befor it enter the parotid gland
1. Posterior Auricular Nerve 2. Digastric nerve 3. Stylohyoid nerve
The five terminal branches
1. Temporal branch
2. Zygomatic branch
3. Buccal branch
4. Marginal mandibular branch
5. Cervical branch
Mohamed el fiky
Course of extracranial part of facial nerve :
1. It leaves the skull through the stylomastoid foramen
2. It curves forwards around the lateral side of the base of the styloid process
3. Then it pierce the posteromedial surface of the parotid gland .
4. It ends inside the gland by dividing into the 5 terminal branches
24. Within the facial canal:
1- Nerve to stapedius: supplies the stapedius muscle.
2- Greater superfacial petrosal nerve (GSPN) : arises from the genicular ganglion
The greater superficial petrosal nerve joins the deep petrosal nerve from the sympathetic
plexus on the internal carotid artery in carotid canal to form the nerve of the pterygoid canal
(vidian nerve) which passes through the pterygoid canal to the pterygopalatine fossa and
ends in the pterygopalatine ganglion
3- Chorda tympani nerve: It arises from the facial nerve 6 mm above the stylomastoid
foramen and runs upwards to perforate the posterior bony wall of the tympanic cavity. It
then passes forwards on the medial surface of the tympanic membrane between its fibrous
and mucous layers crossing the handle of the malleus. Mohamed el fiky
25. âť‘ It comes out of the tympanic cavity through the petrotympanic fissure to the infratemporal
fossa where it joins the lingual nerve.
âť‘ Through the lingual nerve, it supplies both the submandibular and sublingual salivary glands
by secretomotor fibres and taste fibers from the anterior 2/3 of the tongue
II- At the exit from the stylomastoid foramen
1- Posterior auricular nerve: to the auricularis posterior and the occipital belly of the
occipitofrontalis muscle.
2- Digastric branch: to the posterior belly of digastric muscle
3- Stylohyoid branch: to the stylohyoid muscle
Mohamed el fiky
26. TERMINAL BRANCHES
The temporal branches : (frontal branch of the facial nerve) crosses the zygomatic arch to the temporal
region, supplying the auricularis anterior and superior, and joining with the zygomaticotemporal branch
of the maxillary nerve, and with the auriculotemporal branch of the mandibular nerve. The more
anterior branches supply the frontalis, the orbicularis oculi, and corrugator supercilii, and join the
supraorbital and lacrimal branches of the ophthalmic . The temporal branch acts as the efferent limb
of the corneal reflex.
The zygomatic branches : run across the zygomatic bone to the lateral angle of the orbit. Here they supply
the Orbicularis oculi, and join with filaments from the lacrimal nerve and the zygomaticofacial branch of the
maxillary nerve.
The Buccal Branches : (infraorbital branches), of larger size than the rest of the branches, pass
horizontally forward to be distributed below the orbit and around the mouth.
Mohamed el fiky
27. The buccal branch supplies these muscles
The marginal mandibular branch: of the facial nerve passes forward beneath the platysma and depressor
anguli oris. It supplies the muscles of the lower lip and chin, and communicating with the mental branch of
the inferior alveolar nerve Mohamed el fiky
28. The cervical branch of the facial nerve : runs forward It forms
a series of arches across the side of the neck over the
suprahyoid region. One branch descends to join the cervical
cutaneous nerve from the cervical plexus; others supply the
Platysma. Also supplies the depressor anguli oris
Mohamed el fiky
29. Injury at stylomastoid foramen Bell’s Palsy
Race: slightly higher in persons of Japanese descent.
Sex: No difference exists
Age: highest in persons aged 15-45 years. Bell palsy is less common in those younger than 15
years and in those older than 60 years.
Main cause of Bell's palsy is latent herpes viruses (herpes simplex virus type 1 and herpes
zoster virus), which are reactivated from cranial nerve ganglia Polymerase chain reaction
techniques have isolated herpes virus DNA from the facial nerve during acute palsy
• Inflammation of the nerve initially results in a reversible neurapraxia Herpes zoster virus
shows more aggressive biological behaviour than herpes simplex virus
• Type1 Bell's phenomenon is the upward diversion of the eye ball on attempted closure of
the lid is seen when eye closure is incomplete. Mohamed el fiky
31. Clinical correlation: Features of Bell’s Palsy
I. Unilateral involvement
II. Inability to smile, close eye or raise eyebrow
III. Whistling impossible
IV. Drooping of corner of the mouth
V. Inability to close eyelid (Bell’s sign)
VI. Inability to wrinkle forehead
VII. Loss of blinking reflex
VIII.Slurred speech
IX. Mask like appearance of face
X. Loss/ alteration of taste
Mohamed el fiky
Mohamed el fiky
