FACE AND SCALP

Dr. Lubna NazliAssociate Professor Anatomy

Objectives

Face:• Boundaries• Muscles • Blood supply• Nerve supply• Applied anatomy

Scalp:• Extent• Structure• Blood supply• Nerve supply• Applied anatomy

Facial muscles• Epicranius

(occipitofrontalis) – Frontal belly – Occipital belly– Galea aponeurotica

• Orbicularis oculi • Buccinator • Orbicularis oris • Nasalis Platysma

• The skin of face is very thin and connected to the facial bones by loose connective tissue.

• There is no deep fascia. • The facial muscles lie in this connective tissue.

Arteries of headFacial artery

• Branch of external carotid artery.

• Loops around mandible (where it is palpable), at anterior border of masseter, to enter the face

• Follows a tortuous course to medial angle of eye

• Lies deep to most facial muscles

Superficial temporal artery

• Terminal branch of external carotid artery.

• Ascends in front of ear (where it is palpable) to supply temporal and anterior portion of scalp

• Transverse facial artery runs above parotid duct to supply the cheek region

Maxillary artery• Branch of external carotid .• Enters into infratemporal fossa medial to neck of

mandible• Branches

– Inferior alveolar a. – Middle meningeal a.

• enters the skull through foramen spinosum• Supplies cranium and dura mater

– Posterior superior alveolar a.

Veins of head Facial vein• Begins at medial angle of eye

(angular vein)• Runs downward and backward

through the face, posterior to the facial artery

• Below angle of mandible, joins anterior branch of retromandibular vein to form common facial vein, which drains into internal jugular vein

• Connections with cavernous sinus through the ophthalmic vein.

Retromandibular vein • Formed by union of superficial temporal and maxillary

veins• Divides into an anterior branch that unites with facial

vein and a posterior branch that joins posterior auricular vein to become external jugular vein

• “Dangerous area” － lies between root of nose and two angles of mouth; in this area the facial vein has no valves

Nerves of head Facial nerve ( ) Ⅶ Leaves

skull through internal acoustic meatus, facial canal and comes out through the stylomastoid foramen

• Enters parotid gland and divides into its five terminal branches for muscles of facial expression– Temporal – Zygomatic – Buccal – Marginal mandibular

– Cervical

Trigeminal nerve ( )Ⅴ

• Ophthalmic nerve (V1)• Maxillary nerve (V 2) • Mandibular nerve (V 3)

• Supplies sensory innervation to the face.

SCALP

Boundaries• Anterior－ supraorbital

margin• Posterior－ external

occipital protuberance and superior nuchal line

• Lateral－ superior temporal line

Layers • consists of five layers:

– Skin – Superficial fascia – Galea aponeurotica and

occipitofrontalis – Subaponeurotic space

(loose connective tissue)– Pericranium

• The superficial 3 layer are closely knit together, called scalp

• The skin has the greatest concentration of hair and sebaceous glands

• The superficial fascia is dense

connective tissue that binds the skin strongly to the underlying galea aponeurotica – It is richly supplied by

blood vessels. – Wounds of the scalp bleed

profusely but heal well.

• Galea aponeurotica– It is interposed between

the frontalis and occipitalis portions of the occipitofrontalis muscle.

– These muscles place the aponeurosis under tension so that deep transverse lacerations of the scalp gape widely .

• Subaponeurotic space (loose connective tissue)– Extracranial hematoma, the result

of bleeding in the subaponeurotic space, can extend over the cranium. lt can extend posteriorly, to the superior nuchal line; anteriorly, into the eyelids to produce the “black eye”; and laterally, to the temporal line.

– Contains a rich network of deep arteries and veins. Therefore, this layer has been called the “dangerous area”.

– Infection may spread to the substance of the bones, to venous channels within the cranial cavity, or to the brain.

• Pericranium Fuses firmly with bone at

the sutures and with the periosteum of the adjacent bone, thus limiting the sub periosteal space.

Nerve supply

APPLIED ANATOMY

• Facial lacerations• Scalp injuries, infections, cysts.• Paralysis of facial muscles• Trigeminal neuralgia: sensory disorder

• What is the lymphatic drainage of the face and scalp?