What are the 5 layers of the scalp?
Skin Connective tissue Aponeurosis Loose areolar connective tissue Pericranium
Skin of the scalp
Thick, with hair and sebaceous glands
Connective tissue of the scalp
Fibrous, fatty connective tissue with septa that’s connect the skin to the aponeurosis
Aponeurosis of the scalp
- epicranial
- a thin, tendinous sheet that connects the bellies of the occipitofrontalis
Loose aereolar connective tissue of the scalp
Located in the subaponeurotic space
Pericranium of the scalp
The periosteum covering the outer surface of the skull bones
Infections of the superior Sagittal sinus
Can spread to all the veins of the brain
Muscles of the scalp
Occipitofrontalis with 2 bellies
- occipital belly
- frontal belly
What muscle originates from the nuchal line of the occipital bone and inserts into the epicranial aponeurosis?
Occipital belly of the occipitofrontalis muscle
Occipital belly of the occipitofrontalis muscle of the scalp
Originates from the nuchal line of the occipital bone and inserts into the epicranial aponeurosis
What originates from skin and superficial fascia of the eyebrow area and inserts into the epicranial aponeurosis?
The frontal belly of the occipitofrontalis muscle of the scalp
Frontal belly of the occipitofrontalis muscle of the scalp
Originates from the skin and superficial fascia of the eyebrow area and inserts into the epicranial aponeurosis
What is the action of the occipitofrontalis muscle?
Move the scalp on the skull and raise the eyebrows
What is the occipitofrontalis muscle innervated by?
Facial nerve
CN XII
What branch does the supratrochlear and supraorbital come from
Branches of the ophthalmic artery
Where do the nerves lie in the scalp?
Superficial fascia
What is the sensory nerve supply to the scalp?
- supratrochlear nerve
- supraorbital nerve
- zygomaticaotemporal nerve
- auriculotemporal nerve
- lesser occipital nerve
- greater occipital nerve
Supratrochlear nerve
- sensory nerve supply to scalp
- branch of the ophthalmic division of the trigeminal nerve (CNV)
Supraorbital nerve
- sensory nerve supply to the scalp
- branch of the ophthalmic division of the trigeminal nerve (CNV)
Zygomaticotemporal nerve
- sensory supply to the scalp
- a branch of the maxillary division of the trigeminal nerve (CNV)
- cheekbone
Auriculotemporal nerve
- sensory innervation to scalp
- branch of the mandible are division of the trigeminal nerve (CNV)
Lesser occipital nerve
- sensory innervation of scalp
- branch of the cervical plexus (C2)
Greater occipital nerve
-sensory innervation to scalp
Branch of the dorsal ramus of C2
Blood supply to scalp
Extensive supply
What happens if the scalp gets cut?
Profuse bleeding because of extensive blood supply
Arteries of the scalp
- supratrochlear and supraorbital arteries
- superficial temporal artery
- posterior auricular artery
- occipital artery
Supratrochlear and supraorbital arteries
- arterial supply of the scalp
- branches of the ophthalmic artery
- ascend over the forehead
Superficial temporal artery
- arterial supply of scalp
- terminal branch of the external carotid
- ascends in front of the ear
Posterior auricular artery
- arterial supply of the scalp
- branch of the external carotid artery
- ascends behind the ear
Occipital artery
- arterial supply of the scalp
- branch of the external carotid artery
- supplies the skin over the back of the skull
Veins of the scalp
Supratrochlear and supraorbital veins -facial vein Superficial temporal vein Maxillary vein -retromandibular vein External jugular vein Occipital vein
Features of the veins of scalp
Veins of the scalp freely anastomose with each other and are connected to the diploic veins of the skull bones and the intracranial venous sinuses via emissary veins
What forms the facial veins?
The supretrochlear and supraorbital veins unite at the medial margin of the orbit to form this
Where is the facial vein formed?
Memorial margin of the orbit
What forms the retromandibular vein
Superficial temporal vein and the maxillary vein
What forms the external jugular vein
Posterior auricular vein unites with the posterior division of the retromandibular vein
What forms the internal jugular vein
The occipital vein drains into the suboccipital venous plexus, which in turn drains into the vertebral veins or the internal jugular vein
What are the veins of the scalp connected to?
Diploic veins of the skull bones and the intracranial venous sinuses via emissary veins
Where do the lymph vessels in the anterior part of the scalp and forehead drain into?
Submandibular lymph nodes
Where does drainage from the lateral part of the scalp above the ear drain into? (Lymph)
Superficial parotid (preauricular) nodes (before ear)
Lymph vessels in the part of the scalp above and behind the ear drain into…
Mastoid nodes behind the ear
Lymph vessels in the back of the scalp drain into the…
Occipital nodes
Why does the scalp have such abundant blood supply?
The nourish the hair follicles
Small laceration in scalp
Can cause severe blood loss
Why is bleeding of the scalp so hard to stop?
Because the arterial walls are attached to fibrous septa in the subcutaneous tissue
Attachment of the arterial walls to the fibrous septa
Makes the wall unable to contrast or retract to allow blood clotting to take place
What is the only effective way to stop the bleeding?
Local pressure
What is an important factor in deep wounds of the scalp?
The tension of the epicranial aponeurosis, which is produces by the tone of the occipitofrontalis muscle
What is the tension of the epicranial aponeurosis produced by?
The tone of the occipitofrontalis muscle
What happens if the epicranial aponeurosis has been divided?
The scalp wound will gape open
For healing of a scalp laceration..
The cut in the aponeurosis must be sutured
What does the skin of the face posses?
Many sweat and sebaceous glands
What is the skin of the face connected to the underlying bones by?
Loose connective tissue
Where are the muscles of facial expression?
Embedded in the connective tissue
Deep fascia of the face
There is none
Why does the face bruise so easily and movement of the bruise?
Because there is no deep fascia to keep it in one place
What causes wrinkles of the face>
- Repeated folding of the skin perpendicular to the long axis of the underlying muscles
- aging skin loses its elasticity too
Surgical scars on the face
Less conspicuous if they follow the wrinkle lines
What is the sensory nerve supply to the skin of the face?
Three divisions of the trigeminal nerve, except for a small area over the angle of the mandible and the parotid gland, which is supplied by the great auricular nerve (C2 and 3)
What sensory nerve supples the small area over the angle of the mandible and the parotid gland?
Great auricular nerve (C2 and 3)
What else does the trigeminal nerve branches supply?
Sensory information to the mouth, teeth, nasal cavities, and paranasal air sinuses
What are the branches of the trigeminal nerve?
- ophthalmic
- maxillary
- mandibular
Ophthalmic division of the trigeminal nerve supplies what
- skin of the forehead
- upper eyelid
- conjunctiva
- side of the nose down to and including the tip
What are the 5 branches of the ophthalmic division of the trigeminal nerve?
- lacrimal nerve
- supraorbital nerve
- supratrochlear nerve
- infratrochlear nerve
- external nasal nerve
Maxillary division of the trigeminal nerve supplies what
- skin on the posterior part of the side of the nose
- lower eyelid
- cheek
- upper lip
- lateral side of the orbital opening
What are the 3 cutaneous branches of the maxillary division of the trigeminal nerve?
- infraorbital nerve
- zygomaticofacial nerve
- sygomaticaotemporal nerve
Mandibular division of the trigeminal nerve supplies what
- skin of the lower lip
- lower part of the face
- the temporal region
- part of the ear
What are the cutaneous branches of the mandibular division of the trigeminal nerve?
- mental nerve
- buccal nerve
- auriculotemporal nerve
What are the two sources that the face receives its arterial supply from?
- facial artery
- superficial temporal artery
The blood supply of the face is supplemented by…
Small arteries that accompany the sensory nerves of the face
How does the facial artery course?>
Upward and over the submandibular salivary glands
What does the facial artery curve around
The inferior border of the mandible at the anterior border of the masseter muscle
Where can the pulse of the facial artery be felt?
Where it crosses the mandible
What is the facial artery covered by?
Platysma and risorious muscles
Where does the tortuous course of the facial artery go?
From the angle of the mouth to the medial angle of the eye
What happens at the medial angle of the eye to the facial artery?
Anastomoses with branches of the ophthalmic artery
Branches of the facial artery
- submental artery
- inferior labial artery
- superior labial artery
- lateral nasal artery
Superficial temporal artery
- arterial supply of the face
- transverse facial artery (a branch of the superficial artery)
Supraorbital and supratrochlear arteries
- arterial supply of face
- branches of the ophthalmic artery
- supply the skin of the forehead
What are the main arterial supply of the face?
- facial artery (4 branches)
- superficial temporal artery
- supraorbital and supratrochlear arteries (branches of the ophthalmic artery
Where is the facial vein formed ?
At the medial angle of the eye by the union of the supraorbital and supratrochlear veins
What is the facial vein connected to?
The superior ophthalmic vein directly through the supraorbital vein
What is the facial vein connected to by way of the superior ophthalmic vein?
The cavernous sinus
Why is the facial vein connection to the cavernous sinus important?
Because it provides a path for infection to spread from the face to the cavernous sinus
Where does the facial vein descend?
Behind the facial artery to the lower margin of the mandible
Where does the facial vein cross?
Superficially to the submandibular salivary gland and is joined by the anterior division of the retromandibular vein
What does the facial vein drain into?
The internal jugular vein
What does the facial vein receive >
Tributaries that correspond to the branches of the facial artery
What is the facial vein joined to by the deep facial vein?
The pterygoid venous plexus
What is the facial vein joined to the pterygoid venous plexus by?
The deep facial vein
What is the facial vein joined to the cavernous sinus by?
The superior ophthalmic vein
What does the superior ophthalmic vein and facial vein join together to drain to?
Cavernous sinus
What does the transverse facial vein join?
The superficial temporal vein in the parotid gland
What is the main lymph node of the face?
The submandibular lymph nodes
Lymph from the forehead and the anterior part of the face drains into the
Submandibular lymph nodes
Buccal lymph nodes
May be a few of these along the course of the lymph vessels coming from the forehead and the anterior part of the face to the submandibular lymph nodes
What drains into the parotid lymph nodes (in front of ear)?
The lateral part of the face, including the lateral parts of the eyelid is drained by lymph vessels that terminate here
What drains into the submental lymph nodes? (Under the chin)
The central part of the lower lip and the skin of the chin
Where are the muscles of the face embedded?
In the superficial fascia
Where do most of the muscles of facial expression originate>
From the bones of the skull
Where do most muscles of facial expression insert?
Into the skin
What kind of muscles are the facial orifices (orbit, nose, mouth) surrounded by?
Sphincter or dilators
What are all facial muscles innervated by?
Facial nerve (CN VII)
What is the sphincter muscles of the eyelid?
Orbicularis oculi
What are the dilator muscles of the eyelid?
- Lavatory palpebrae superioris
- Occipitofrontalis
Sphincter muscles of the nose
Compressor nares
What is the dilator muscle of the nose?
Dilator naris
Sphincter muscle of the mouth
Orbicularis oris
Dilator muscles of the mouth
Consist of a series of small muscles that radiate out from the lips
-innervated by the buccal nerve
Sphincter muscles of the lips
Orbicularis oris
What is the orbicularis oris innervated by?
Buccal and mandibular branches of the facial nerve
What is the action of the orbicularis oris?
Compress the lips together
Dilator muscles of the lips
Radiate out from the lips
Action of the dilator muscles of the lips
Separate the lips
What are the dilator muscles of the lips?
- lavator labii superioris alaeque nasi
- lavatory labii superioris
- zygomaticus major and minor
- elevator anguli oris
- risorious
- depressor anguli oris
- depressor labii inferioris
- mentalis
What are the dilator muscles of the lips innervated by?
Buccal and mandibular branches of the facial nerve
Where does the buccinator originate from?
The outer surface of the alveolar margins of the mandible and maxilla, opposite the molars; it also originates from the pterygomandibular ligament
What pierces the buccinator?
Parotid duct (salivary gland)
What happens to the buccinator muscle at the angle of the mouth?
Muscle fibers decussate (cross) and then blend with and forms part of the orbicularis oris
What is the buccinator muscle innervated by?
Buccal branch of the facial nerve
What is the action of the buccinator muscle ?
Compress the cheeks and lips against the teeth (trumpeters muscle)
Facial nerve direction
Runs forward in the substance of the parotid gland, where it divides into its five terminal branches
What kind of innervation does the facial nerve have
Motor
What are the five branches of the facial nerve?
- temporal branch
- zygomatic branch
- buccal branch
- mandibular branch
- cervical branch
Temporal branch of the facial nerve
Supplies the anterior and superior auricular muscles, frontal belly of occipitofrontalis, orbicularis oculi, and corrugator supercilii
Zygomatic branch of the facial nerve
Supplies the orbicularis oculi
Buccal branch of the facial nerve
Supplies the buccinator, muscles of the upper lip and nostril
Mandibular branch of the facial nerve
Supplies the muscles of the lower lip
Cervical branch of the facial never
Supplies the platysma muscle
