Face Anatomy PDF

FACE  Skin & fascia Muscles Development Sensory nerves & its innervation Arterial supply Venous drainage Lymphatic drainage  Development of face Begins with development of FRONTONASAL PROCESS & PHARYNGEAL ARCHES Pharyngeal...

FACE  Skin & fascia Muscles Development Sensory nerves & its innervation Arterial supply Venous drainage Lymphatic drainage  Development of face Begins with development of FRONTONASAL PROCESS & PHARYNGEAL ARCHES Pharyngeal arches  Form at 4 - 5th week of development  Give rise to muscles & skeletal structures of face & neck Pharyngeal Skeleton Muscles Nerve arch 1st Mandible, maxilla, Mastication, mylohyoid, CN V2,3 (maxillary zygomatic, anterior belly of digastric, & mandibular) part of temporal, tensor palatine, tensor incus & malleus. tympani 2nd Stapes, styloid process, Facial expression, CN VII (facial) lesser horn & upper part of posterior belly of digastric, body of hyoid stylohyoid, stapedius Facial processes End of 4th week of development >> d/ment of facial processes (frontonasal, maxillary & mandibular) Developed from 1st pharyngeal arch Process Structure formed Nerve supply Frontonasal p. Forehead, nose, philtrum Ophthalmic CN V1 of upper lip, frontal bone Maxillary p. Upper cheek region, lat. Maxillary CN V2 (of 1st pharyngeal arch) portion of upper lip, maxilla Mandibular p. Lower lip, chin, lower Mandibular CN V3 (of 1st pharyngeal arch) cheek region, mandible Skin & Fascia of face  Skin - Contains numerous sweat & sebaceous gland (acne & sebaceous cysts) - Thin on the eyelids  Fascia - Superficial fascia encloses: muscles of facial expression / bld vessels / nn. - NO deep fascia EXCEPT around parotid gland Sensory nerves of face  Branches of trigeminal nerve (CN V) *Ophthalmic nerve  supplies frontonasal process *Maxillary nerve  maxillary process of 1st pharyngeal arch *Mandibular nerve  mandibular process of 1st pharyngeal arch  Great auricular nerve (C2,3)  Angle of mand. & parotid gland Little overlap in innervation Ophthalmic nerve CN V1 – Branches:  Lacrimal nerve - Skin & conjunctiva of lat. part of upper eyelid  Supraorbital nerve - Skin & conjunctiva of central part of upper eyelid, skin of forehead  Supratrochlear nerve - Skin & conjunctiva of med. part of upper eyelid, skin of lower part of forehead  Infratrochlear nerve - Skin & conjunctiva of medial part of upper eyelid, skin at side of nose  External nasal nerve - Skin of nose Maxillary nerve CN V2– Branches:  Zygomaticotemporal nerve - Skin over the temple  Zygomaticofacial nerve - Skin over prominence of cheek  Infraorbital nerve - Direct continuation of CN V2 - Skin of cheek, lower eyelid, side of nose & upper lip Mandibular nerve CN V 3– Branches:  Auriculotemporal nerve - Skin of auricle, ext. auditory meatus, outer surface of tympanic membrane, skin of scalp above auricle  Buccal nerve - Skin over small area of cheek  Mental nerve - Skin of the lower lip & chin  Branches of trigeminal nerves also supply: * Sensory of mouth, tongue, teeth, nasal cavity & paranasal sinuses Mm of mastication * Motor (CN V3) to muscles of mastication, mylohyoid, anterior belly of digastric, tensor veli palatini & tensor tympani.  Lesions of trigeminal nerve  Widespread anaesthesia of - Corresponding anterior half of scalp - Face, except angle of the mandible - Mucous membrane of nose, mouth & anterior part of tongue  Paralysis of muscles of mastication Testing the integrity of CN V  Trigeminal neuralgia  Sudden attack of excruciating pain in distribution of CN V2 & V3  Causes ? - Abn blood vessels/ tumor – compressing at the root of CN5 - Demyelination of axons (Multiple sclerosis) - Injury to the nerve a.r.o infection / surgical procedure Muscles of face & its innervation  1) Muscles of facial expression  Embedded in superficial fascia - Arises from bones of skull  inserted into skin  Function: - Sphincter & dilator of face orifice (eye, nose, mouth) - Modify expression of face Category of facial Muscles muscle Muscle of forehead Frontal belly of occipitofrontalis Muscles of eyelids Orbicularis oculi, levator palpebrae superioris, corrugator supercilii Muscles of nostrils Nasalis, procerus Muscles of lips Orbicularis oris, Levator labii superioris (LLS), LLS alaeque nasi, Zygomaticus major & minor, Levator anguli oris, Depresor anguli oris, Depressor labii inferioris, Mentalis, Risorius Muscle of cheek Buccinator Nasalis 1a) Muscle of forehead 1b) Muscles of eyelids Orbital portion tightly Contraction of palpebral part closes (ie winking) 1c) Muscles of nostrils Nasalis (Compressor naris & dilator naris), 1d) Muscle of lips 1d) Muscle of cheek Nerve supply to mm of facial expression:  Motor innervation by facial nerve (Nerve of 2nd pharyngeal arch)  Proprioceptive impulses conveyed by trigeminal nerve Terminal branches (*Supply mm of facial expression): CN VII branches Auricularis anteror & superior, frontal belly of occipitofrontalis, superior part of orbicularis oculi Branches before entering parotid gland: Inferior part of orbicularis oculi, facial Auricularis posterior, muscles inferior to orbit occipital belly of occipitofrontalis Buccinator, muscles of upper lip Muscular branch Posterior belly of Muscles of lower lip digastric, stylohyoid Platysma  Facial muscle paralysis/ Bell’s palsy  Injury to facial nerve & its branches - Paralysis of some/ all facial muscles on the affected side No transverse wrinkles Unable to close the eye Drooping of lower eye lid - Lacrimal fluid not spread  ulceration of cornea Drooping of angle of mouth -Not drawn up while smiling -Food accumulate in vestibule -Saliva trickles down 2) Muscles of mastication  Developed from 1st pharyngeal arch - Masseter, temporalis, lateral & medial pterygoid  Motor innervation by mandibular nerve CN V3 Student task: Find origin / insertion / action muscles of mastication.  Arterial supply of the face  From external carotid artery - Facial artery - Transverse facial artery (branch of superficial temporal artery) - Maxillary artery  From internal carotid artery - Supraorbital & supratrochlear arteries (branches of ophthalmic artery)  : branches of ECA Superficial Transverse facial a. temporal a. Sup. labial a Maxillary a. Inf. labial a. Facial a.  Anastomosis between branches of ICA (ophthalmic a via supratrochlear / supraorbital aa) & branch of ECA (sup. temp. a) - Prevent cerebral ischemia (artherosclerosis of internal carotid artery)  Pulse of facial artery - Inferior border of mandible - In front of anterior border of masseter  Venous drainage of the face  Accompany arteries of the face - Supratrochlear & supraorbital veins  facial vein + ant. branch of r/mand v.  IJV - Superficial temporal v & maxillary v  retromandibular vein Ant. branch of retomand vein  Deep venous anastomoses  Facial vein (valveless) - Joined to carvenous sinus by superior ophthalmic vein - Joined to pterygoid venous plexus by deep facial vein  Danger area of the face  Connection of facial vein - Cavernous sinus - Pterygoid venous plexus  Infection of face may spread to dural venous sinuses - Squeezing of pimples on the side of nose & upper lips  Lymphatic drainage of the face  NO lymph nodes in the face - Except in the parotid/ buccal region - Lymph from parotid / buccal lymph nodes  submand, submental lymph nodes  deep cervical lymph nodes THANK YOU The end