6. head face
TRANSCRIPT
HEAD: CRANIUM(SCALP) AND FACE
THE HEAD
BOUNDARIES Lower border of mandible Angle of mandible Mastoid process Superior nuchal line External occipital protuberance
DIVISION Face Cranium(Supraorbital margin,
Zygomatic arch, Superior border of External acoustic meatus, Mastoid process)
THE CRANIAL PART
THE CRANIUM DIVISION THE VERTEX(CALVARIA)
Frontoparietoccipital regionTemporal region
BASE OF CRANIUM(BASE OF SKULL)
Internal surfaceExternal surface
CAVITY OF CRANIUM(CRANIAL CAVITY)BrainMeninges and blood vesselsCranial nerves
FRONTAL PARIETAL OCCIPITAL REGION
Boundaries Anterior -
supraorbital margin Posterior - external
occipital protuberance and superior nuchal line
Lateral - superior temporal line
SCALP
Soft tissue covering the cranial vault It is hair bearing area of the skull Extend from supra orbital margin anteriorly
to external occipital protuberance & superior nuchal line posteriorly
On each side to superior temporal line
SCALP S-Skin C-connective tissue (superficial fascia) A-aponeurosis (galea aponeurotica)/
Occipitofrontalis L-loose areolar tissue P-pericranium
SKIN Thick and hairy Firmly attached to the epicranial aponeurosis
through dense fascia Abundance sebaceous glands Sebaceous cyst are common
CONNECTIVE TISSUE Fibrous and dense containing blood vessels and
nerves Binds skin to subjacent aponeurosis Wounds bleed profusely as blood vessels are
prevented from retraction by fibrous tissue. Bleeding is stopped by applying pressure against the bone
Subcutaneous hemorrhage are not extensive since fascia is dense
Inflammation cause little swelling but are much painful
APONEUROSIS Anteriorly frontal belly and
posteriorly occipital belly of occipitofrontalis muscle
Frontal belly originate from skin of forehead and mingled with orbicularis oculi muscle
Occipital belly originate from lateral 2/3 of superior nuchal line
It gaps if cut transversely and should be stitched
LOOSE AREOLAR TISSUE
Extends anteriorly into the eyelids because frontalis has no bony attachment
Posteriorly to superior nuchal line On each side to superior temporal line Bleeding cause generalized swelling of scalp Called dangerous layer of scalp-emissary veins
open here and carry any infections inside the brain (venous sinus)
Bleeding lead to black eye Caput succedaneum in new born
PERICRANIUM
Is the periosteum of skull Loosely attached to surface of bone but is
firmly adherent to the sutures Injury deep to it take the shape of bone
(cephalhaematoma) Scalping injury- should be replaced and
stitched because healing is better
Caput succedaneum cephalhaematoma
TEMPORAL REGION
Boundaries Superior - superior
temporal line Inferior - superior
border of zygomatic arch
Anterior - the junction of frontal and zygomatic bones
Posterior - posterior portion of superior temporal line
TEMPORAL REGION
Layers consists of five layers:
Skin Superficial fascia Temporal fascia Temporalis Periosteum
BLOOD SUPPLY
Arteries Supratrochlear Supraorbital Superficial temporal Posterior auricular
artery Occipital artery
Veins-follows the artery
NERVE SUPPLY In front of auricle
Supratrochlear n. Supraorbital n. Zygomaticotemporal n. Auriculotemporal n. Temporal branch of
facial n. Behind auricle
Greater auricular n Lesser occipital n. Greater occipital n. Third occipital n. Post. Auricular branch of
facial n.
LYMPHATICS Anterior part
Preauricular (parotid) gr. of lymph node Posterior part
Posterior (mastoid) gr. of lymph node &occipital gr. of lymph node
FACE
Boundaries Extends superiorly to the hair line, inferiorly
to the chin and base of mandible, and on each side to auricle
Forehead is common to both scalp and face
SKIN Very vascular Due to rich vascularity face blush and
blanch Wounds of face bleed profusely but heal
rapidly Results of plastic surgery are excellent on
face Facial skin is rich in sebaceous gland and
sweat gland Sebaceous gland keep the skin oily but
also cause acne in adult Sweat gland regulate body temperature
FACIAL MUSCLE Called muscle of facial expression and
lie in superficial fascia Embryologically they develop from
mesoderm of 2nd branchial arch, therefore supplied by facial nerve
ORBICULARIS OCULI
3 parts- Orbital part
Originate from medial part of medial palpebral ligament and form concentric rings, return to point of origin
Action –closes the lids tightly Palpebral part
Originate from lateral part of medial palpebral ligament Insert into lateral palpebral raphe
Action-closes the lids gently Lacrimal part
Originate from lacrimal fascia& lacrimal bone Insert into upper &lower tarsi
Action-dilate lacrimal sac
ORBICULARIS ORIS
Originate from maxilla above incisor teeth and insert into skin of lip.
Action –closes the mouth
BUCCINATOR Upper fibers
Origin- from maxilla opposite molar teeth
Insertion-upper lip Lower fibers
Origin-from mandible opposite molar teeth
Insertion-lower lip Middle fibers
Origin –from pterigomandibular raphe
Insertion-decussate before passing to lips
Action- prevent accumulation of food in vestibule of mouth
PLATYSMA Origin– upper part of
pectoral and deltoid fascia
Insertion– base of mandible, skin of lower face and lip
Action– releases pressure of skin on the subjacent veins, depress mandible, pulls angle of mouth downwards
MASTICATORY MUSCLES Masseter
Origin - inferior border and medial surface of zygomatic arch
Insertion - lateral surface of ramus of mandible and angle of mandible
Action - elevates mandible
Temporalis Origin - temporal
fossa Insertion - coronoid
process of mandible Action - elevates and
retracts mandible lateral pterygoid Medial pterygoid
NERVE SUPPLY OF FACE
Motor supply Facial nerve\
Leaves skull through internal acoustic meatus, facial canal and stylomastoid foramen
Divided three parts First part - between
stylomastoid foramen and parotid gland
Second part - within parotid gland
Third part - outside of parotid gland
SENSORY SUPPLY TRIGEMINAL NERVE Ophthalmic division
Supratrochlear Supraorbital Lacrimal Infratrochlear External nasal
Maxillary nerve Infraorbital Zygomaticofacial and
zygomaticotemporal Mandibular nerve
Auriculotemporal Buccal nerve Mental
Skin over the mandibular angle is supplied by ant. Div. Of greater auricular n.
BLOOD SUPPLY OF FACE
Arterial supply- Facial artery Superficial temporal
artery Ophthalmic artery
Supraorbital and Supratrochlear
VENOUS DRAINAGE Vein follow the arteries
and drain into common facial vein and retromandibular vein
Deep connections of facial vein-
Communication between supraorbital &superior ophthalmic vein
With pterigoid plexus of vein through deep facial vein.
Superior ophthalmic vein & ptergoid plexus of vein communicate with cavernous sinus
LYMPHATIC DRAINAGE 3 territories- Upper territories- greater
part of forehead, lateral ½ of eye lid, conjunctiva, lateral part of cheek and parotid area– preauricular lymph node (parotid)
Middle territories- median part of forehead, external nose, upper lip, lateral part of lower lip, medial ½ of eye lid, medial part of cheek, greater part of lower jaw– submandibular lymph node
Lower territories- central part of lower lip, chin– sub mental lymph node
APPLIED
Trigeminal neuralgia Maxillary and mandibular nerve are involved Excruciating pain in the region of distribution of
these nerve In infranuclear lesions of facial nerve (eg,
bell’s palsy)- whole face is paralyzed c/f
Affected side is motionless Loss of wrinkles Eye cannot be closed In smiling the mouth is drawn to normal side During mastication food accumulates in vestibule of
mouth In supranuclear lesions of facial nerve only
the lower part of face is paralyzed. The upper part (frontalis &part of orbicularis oculi) escapes due to its bilateral innervation
Dangerous area of face- infections from face mainly from upper lip & nose can go to cavernous sinus through ophthalmic vein and deep facial vein