face and scalp dr. lubna nazli associate professor anatomy
TRANSCRIPT
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?