Clinical Anatomy of the Head PDF

CLINICAL ANATOMY OF THE HEAD PART 1 BY Jerzy Gielecki MD, PhD, DSc. Anna urada MD, PhD. Olsztyn 2010 1 This guide of Head is created for the students to understand the basic fundamentals concerning the morphology of the bones, muscles, nerves and vessels of the head. I would like to express great ap...

CLINICAL ANATOMY OF THE HEAD PART 1 BY Jerzy Gielecki MD, PhD, DSc. Anna urada MD, PhD. Olsztyn 2010 1 This guide of Head is created for the students to understand the basic fundamentals concerning the morphology of the bones, muscles, nerves and vessels of the head. I would like to express great appreciation to my colleagues for their insight and dedication towards the completion of this manual. I am indebt to the students, members of the Anatomical Research Group for their advice. Jerzy Gielecki M.D., Ph.D, D.Sc. CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 2 Lab. session 1 1. Regions of the head....................................................................... 3 2. The scalp......................................................................................... 4 3. Fascia of the head.......................................................................... 5 4. Muscles of the face........................................................................ 6 5. The Facial Nerve - CN VII............................................................. 11 6. Parotid gland................................................................................ 19 7. Clinical Notes............................................................................... 20 CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 3 1. Regions of the head 1. Forehead or frontal region (frons) 2. Parietal region (regio parietalis) 3. Occiput or occipital region (regio occipitalis) 4. Temple or temporal region (regio temporalis) 5. Ear or auricular region (auris) 6. Mastoid region (regio mastoidea) 7. Face or facial region (facies) Suprapalpebral groove (sulcus suprapalpebralis) Eye or orbital region (oculus) Infrapalpebral groove (sulcus infrapalpebralis) Infra-orbital region (regio infraorbitalis) Cheek or buccal region (bucca) Parotid region (regio parotideomasseterica) Zygomatic region (regio zygomatica) Nose or nasal region (nasus) Nasolabial groove (sulcus nasolabialis) Mouth or oral region (regio oralis) Mentolabial groove (sulcus mentolabialis) Chin or mental region (regio mentalis) CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 4 Fig. 1-1. Regions of the head & neck – lateral view. 2. The scalp The scalp is a soft tissue that covers the vault of the skull. The scalp consists of five layers (listed from the surface inwards): a. skin within the hair b. dense connective tissue – highly vascular c. epicranial aponeurosis with the occipitofrontal muscle d. loose connective tissue – this is tissue upon which the aponurosis glides e. pericranium (periosteum) – adherent to the bony part of the skull A good way to remember the five layers of the scalp is the following mnemonic: S - Skin C - Connective tissue A - Aponeurosis L – Loose connective tissue P - Periosteum CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 5 Fig. 1-2. Nerve supply of the scalp region. 3. Fascia of the head Fascia of the head (fascia capitis ) includes three elements: i. Buccopharyngeal fascia (fascia buccopharyngea) - covers the external surface of the buccinator muscle and pterygomandibular raphe. num ii. Temporal fascia (fascia temporalis) has two parts: a. num Superior part is attached to the m superior u temporal line. It is a strong, fibrous sheet for m the attachment of some fibres of the temporal muscle b. Inferior part has two layers: - mum Superficial layer (outer) attaches to the seemin lateral border of the zygomatic arch then continues below as the masseteric fascia - Deep layer ends by attaching to the medial surface of zygomatic arch. sur iii. mus Parotid-masseteric fascia (fascia parotideo-masseterica) covers thelateral surface of the masseter muscle and m splits to enclose the parotid gland. This fascia joins with the inin num investing layer of the deep cervical fascia. CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 6 4. Muscles of the face Muscles of the face are divided into three groups: 4.1. Muscles of the scalp Muscles of the scalp = epicranius (musculus epicranius) The epicranial aponeurosis (galea aponeurotica) is a continuous musculomembraneous mu sheet which contains the occipitofrontal muscle. It extends from the external occipital protuberance and supreme nuchal line to the eyebrows. -use a. the occipitofrontal muscle (musculus occipito-frontalis) is a part of the scalp muscle with its: frontal belly - transverse wrinkles on the skin of the forehead occipital belly - assists the frontalis b. the temporoparietal muscle (musculus temporoparietalis). occipitationtal temporoparietal 4.2. Muscles of facial expression Muscles of the facial expression (musculi faciales) consist of the muscles of the face.m There is no deep fascia on the face. Muscles of the facial expression have attachment to the skin and mu ~ do not have fascia except fascia for the buccinator. The muscles of the facial expression are innervated by the facial nerve (CN VII). n a. Orbital group includes 3 muscles: 1. orbicularis oculi muscle (musculus orbicularis oculi) with three parts: orbital part palpebral part lacrimal part Function: s Sphincter of the palpebral fissure, closes the lid, and compresses the lacrimal sac. vo e rn e n m es 2. corrugator supercilii muscle (musculus corrugator supercilii) Function: Assists the frontalis and elevates the supercilii num 3. depressor supercilii muscle (musculus depressor supercilii) Function: Depresses the supercilii num b. Nasal group includes 3 muscles: 1. Procerus muscle (musculus procerus) which transverse folds of the skin across the root of ~ the nose 2. Nasal muscle (musculus nasalis) with two parts: transverse part = compressor naris muscle alar part = dilator naris muscle Function: m compresses and flares the naris 3. Depressor septi muscle (musculus depressor septi) which depresses the septal cartilages c. Circum-oral group includes 10 muscles which split into upper and lower group: Upper Gro up: CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 7 1. levator labii superioris alaeque nasi muscle (musculus levator labii superioris alaeque nasi) which m elevates the upper lip and dilates the nares um 2. levator labii superioris muscle (musculus levator labii superioris) which elevates the ~ upper lip 3. zygomaticus minor muscle (musculus zygomaticus minor) which forms the nasolabial depression umu ~ 4. zygomaticus major muscle (musculus zygomaticus maior) which musi acts during smiling 5. risorius muscle (musculus risorius) which ~ function is grining 6. levator anguli oris muscle (musculus levator anguli oris) 7. buccinator muscle (musculus buccinator) - - Fig. 1-3. Muscles of the face & their functions Lower Gro up: 8. depressor labii inferioris muscle (musculus depressor labii inferioris) 9. depressor anguli oris muscle (musculus depressor anguli oris) 10. mentalis muscle (musculus mentalis) CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 8 Fig. 1-4. Muscles of the head 4.1. Muscles of the mastication The muscles of mastication consist of four muscles: 1. masseter muscle (musculus masseter) which is thick, quadrangular muscle and it can be palpated as it lies superficial to the angle of the mandible. must It closes the jaw and elevates the mandible. ORIGIN: zygomatic arch ~ INSERTION: the masseteric tuberosities on the lateral surface of the i coronoid process n um and the ramus of the mandible to the angle u m ~ INNERVATION:nerve to masseter (a branch of CN V3 or mandibular nerve) which is reaches the muscle via the ~ mandibular notch m 2. temporalis muscle (musculus temporalis) is located in the temporal fossa between the superior temporal line and the zygomatic arch. minimum ORIGIN: from the m inferiorm temporal line, lining of the temporal fossa (note that its tendon m descends medial to the zygomatic arch) INSERTION: i coronoid process of the ramus of the mandible i n ~ FUNCTION: m closes and retracts the mandible (posterior fibers) usi INNERVATION: m deep temporal nerves (branches of CN V3) i ss i - CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 9 Fig. 1-5. Masticatory muscles 3. lateral pterygoid muscle (musculus pterygoideus lateralis) which has its attachments place for upper head into the infratemporal crest and infratemporal surface of greater wing of the sphenoid and for lower head into the lateral surface of the lateral pterygoid plate. INSERTION: mumummunu both heads to the neck of the mandible FUNCTION: mini opens the jaw and protrudes the mandible INNERVATION: branch of the mandibular nerve (CN V3) u mu ~ 4. medial pterygoid muscle (musculus pterygoideus medialis) which is short and thick muscle. It is found as a horizontally oriented structure that lies within the upper part of the infratemporal fossa. The muscle is found medially to the insertion of temporalis muscle and ramus of the mandible. The fibers of this muscle are directed exactly as those of the masseter muscle. The medial pterygoid muscle occupies the same position as does the masseter muscle. The pterygoid is located on the internal surface and masseter on the external surface of the angle of the mandible ORIGIN: from the mu pterygoid fossa INSERTION: the pterygoid tuberosities min FUNCTION: closes the jaw and also participates in the protrusion of the mandible aided by mumum the lateral pterygoid muscle and masseter muscle INNERVATION: nerve to the medial pterygoid muscle (a branch of the trunk of the CV3) numum CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 10 Fig. 1-10. Cranial Nerves (CN) & their fibres 1. Oh Once One Tries Taking Anatomy Finding Very Good Vacations Appear History 2. Some Say Marry Money But My Brother Says Big Brains Matters More CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 11 5. The Facial Nerve The facial nerve (nervus facialis) is divided into a proper (motor) part and an intermediate ~ m part (CN VII a taste and parasympathetic fibers). num The proper part includes: - Motor fiber s goes to the~ muscles of facial expression (this component innervates musculature derived from pharyngeal arch II). The motor root exits the brain (posterolateral border of the pons) in the cerebellopontine angle mini together with the CN VIIa and the CN VIII, medial to the CN VIII. i minine The intermediate part called as INTERMIDIATE NERVE -CN VIIa (nervus intermedius) m or ~ nerve of Wrisberg includes: - ~ Special Visceral Afferent (SVA) - taste fibers from the anterior two-thirds of tongue m mmun mmmmmmmm and palate m -~ General Somatic Afferent (GSA) sensory fibers that lead sensation frommini posterior region of external auditory canal and posterior part of pinna. mini ~ It goes to two parasympathetic ganglia: i pterygopalatine and submandibular ganglion that are s eem associated with the facial nerve. CN VIIa has secretion function for lacrimal, minor salivary glands, sublingual and submandibular glands. CN VIIa is called as intermedius nerve because it goes between the motor root of CN VII and CN VIII in the cerebellopontine angle. The CN VII has the following nuclei: Proper part: a. Motor Nucleus of Facial Nerve is located in the reticular formation of the lower pons and the upper medulla and its ~ Somatic Visceral Efferent (SVE) motor fibers are distribute to the muscles of the face. Fibers to the auricular and occipital muscles from the dorsomedial part of cell group, to the platysma from the ventromedial part. Fibers to stapedius, temporalis and zygomatic are sends main part. - Intermediate part: b. Solitary Tract Nucleus (gustatory nucleus) located in the medulla. Gustatory or Special Visceral Afferent (SVA) fibers from taste buds of anterior 2/3 part of the tongue are carried to geniculate ganglion via chorda tympani. Solitary tract nucleus also synapse fibers from pharynx, oral cavity and larynx goes by CN IX, CN X. c. Superior Salivatory Nucleus (secretomotor nucleus) ~ is a parasympathetic nucleus. It gives off a mini General Visceral Efferent (GVE) fibers which are going via CN VIIa d. Principal Sensory Nucleus of Trigeminal Nerve forms a sensory nucleus located in the pons. It takes a General Sensory Afferent (GSA) fibers from the mastoid region, lateral pinna vin ~ and the external auditory canal via the posterior auricular nerve and next via CN VIIa. ~ Geniculate Ganglion (GG) has cell bodies ofm SVA taste fibers of CN VIIa and m GSA somatic fibers. The preganglionic GVE and SVE pass throught GG without synapsing ~ CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 12 Fig. 1-11. The nuclei of CN VII and their fibres. Geniculate ganglion (1), stylomastoid foramen (2), , chorda tympani (3), submandibular ganglion (4), petrosus major nerve goes to pterygopalatine ganglion (5) Upper Motor Neuron (UMN) = Supranuclear Control: Cortical fibres for the upper face project to both side. It is the ipsi- and contralateral facial nucleus. The supranuclear fibres for the lower facial muscles foes only to the contrlateral facial nucleus. That’s way unilateral supranuclear lesions characteristically spare the function of the upper face. CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 13 Lower Motor Neuron (LMN) = peripheral route of CN VII CN VII axons pass through the transverse fibers of the middle cerebellar peduncle within the subarachnoid space of cerebellopontine angle. CN VII is joined by CN VII which is going inferior and lateral to CN VII. CN VIIa runs between CN VIII and motor root of CN VII (its name). Hemiparesis: - ipsilateral to facial paralysis suggest a cortical or subcortical lesion - contralateral suggest a pontion lesions near the motor nucleus of facial nerve Loss of sensation to peripheral to prinpich temperature, light touch or vibration of the face or body contre- or ipsilateral suggest lateral braistem involvement or cerebellopontine angle lesion. Central (supranuclear) facial palsy (paresis) only the lower face is paralyzed especially muscles Nuclear or pontine lesions – lesions near the facial nucleus an ipsilateral facial palsy is seen with a contralateral hemiplegia (corticospinal tract has not crossed yet). Course of the CN VII: The beginning of both parts of the facial nerve (proper and intermediate) is similar. The smaller part of the CN VII is formed by the intermediate part (CN VIIa) and lager part is formed by the proper part. The rootlets of the facial nerve emerge from the lower lateral surface of the pons and pass laterally with the vestibulocochlear nerve through the internal auditory meatus to an enlargement called the geniculate ganglion (L. genu = knee-like). The intermediate nerve can be located at the internal acoustic meatus as a small filament positioned between the motor part of CN VII (above CN VIIa) and CN VIII (below CN VIIa). After emerging through the internal acoustic meatus, the facial nerve turns abruptly in the posterior direction. It passes through the bony canal on the medial wall of the middle ear and proceeds downward where it emerges from the temporal bone through the stylomastoid foramen. The nerve then continues forward to enter the parotid gland where it divides into a number of branches. - lower lateral - surface of pons "branches" internal auditory > - geniculate meatus M & E ① parotid gland [ ganglion - > - posterior direction stylomastoid foramen ( I bony Canal of middle ear CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 14 Superior salivary nucleus para-symph - secretomotor Motor nucleus of facial Internal auditory meatus Geniculate ganglion Greater petrosal nerve to nn. of pterygoid canal to pterygopalatie ganglion Nerve to stapedius m. Taste fibres of CN VII run with branches of lingual n. to tongue Nucleus of tractus solitarius ( taste) Stylomastoid foramen Chorda tympani nerve joining lingual Secretomotor fibres of facial to submandibular and sublingual salivary glands via relay in submandibular ganglion Fig. 1-12. Relations of the facial nerve B. The branches of the proper part of facial nerve are as follow: - nerve to stapedius (nervus stapedius) to the stapedius muscle - digastric branch (ramus digastricus) to the posterior belly of digastric - stylohyoid branch (ramus stylohyoideus) to the stylohyoid - posterior auricular nerve (nervus auricularis posterior) arises just below the stylomastoid foramen to supply the occipitalis and the auricular muscles. Within the parotid gland, the facial nerve forms the parotid plexus (plexus intraparotideus) and gives several branches. TO ZOO BY MOTOR CAR (mnemonic to remember the branches) 1. 2. 3. 4. 5. TEMPORAL BRANCH -- Frontal Muscles ZYGOMATIC BRANCH -- Orbicularis Oculi BUCCAL BRANCH -- Buccinator, Orbicularis Oris, Zygomaticus MANDIBULAR BRANCH -- Orbicularis Oris, Depressor Labii Inferiores CERVICAL BRANCH -- Platysma CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 15 Fig. 1-12. The motor branches of CN VII & supplying muscles C. Branches of the CN VIIa are as follow: - Greater petrosal nerve (nervus petrosus major) leaves the facial nerve at the geniculate ganglion and passes through the petrosus part of the temporal bone (hiatus for the greater petrosal nerve) into the middle cranial fossa. It traverses the fossa to reach the foramen lacerum and joins the deep petrosal nerve (a sympathetic branch from the internal carotid plexus) to form the nerve of the pterygoid canal. The nerve passes through the pterygoid canal of the sphenoid bone to reach the pterygopalatine ganglion in the pterygopalatine fossa. It gives of preganglionic parasympathetic fibres to the lacrimal gland, palatine, and nasal glands. PATHWAY OF GREATER PETROSAL Middle Ear ------> Out the Greater Petrosal Hiatus ------> back in through the foramen lacerum ------> Join with sympathetics from Deep Petrosal Nerve to form the Nerve of Pterygoid Canal ------> Pterygopalatine Ganglion, where it synapses ------> Nasal mucosa and Lacrimal Glands. - Chorda tympani (chorda tympani) contains taste fibers that pass as preganglionic fibers from the anterior two-thirds of the tongue and are situate in the geniculate ganglion. It also contains parasympathetic preganlionic fibres that pass to the submandibular, sublingual, and lingual ganglions. This nerve enters the lingual nerve where both fibers travel together. The preganglionic fibres emerge from the main trunk of the lingual nerve to supply the submandibular ganglion. The submandibular ganglion sends postganglionic fibres (glandular branches) to supply the submandibular gland. The remaining postganglionic parasympathetic efferent fibres (secretomotor) renter the lingual nerve by which they are distributed to supply the sublingual and the anterior lingual glands. CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 16 PATHWAY OF CHORDA TYMPANI Through Middle Ear ------> Out the Petrotympanic Fissure ------> Joins up with the Lingual Nerve ------> Submandibular Ganglion, where it synapses ------> Sublingual and Submandibular Salivary Glands Fig. 1-13. Parotid gland and facial nerve Course of the chorda tympani: It arises just above the stylomastoid foramen and enters the tympanic cavity by a small posterior canaliculus. It passes forward through the middle ear and is covers by the mucous lining of the tympanic membrane. The handle of the malleus is located laterally and the incus medially. It leaves the tympanic cavity by a small anterior canaliculus through the petrotympanic fissure (locate this fissure within the medial wall of the mandibular fossa). After receiving a small communicating branch from the submandibular ganglion, the chorda tympani joins the sensory filaments of the lingual nerve to reach the structures of the tongue. D. Pathways of CN VII: Motor fibres: The motor nucleus of the facial nerve is located in transition between the pons and the medulla. It enters the facial canal through the internal acoustic meatus to reach the geniculate ganglion. It exits the facial canal through the stylomastoid foramen and suddenly splits into terminal branches inside the parotid gland CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 17 Fig. 1-14. Distribution of terminal part of facial nerve Sensory fibres: (taste fibres) from the anterior 2/3 of the tongue course along the lingual nerve to: Chorda tympani nerve Through petrotympanic fissure Through tympanic cavity Enters facial nerve Geniculate ganglion Intermedial part of CN VII Solitary tract nucleus in medulla Parasympathetic fibres - Secretomotor fibres (part I): Originates in the superior salivary nucleus Intermedial part of CN VII Geniculate ganglion Facial nerve Chorda tympani Submandibular ganglion Pathway divides into A. and B. Parasympathetic fibres - Secretomotor fibres (part II): Originates in the superior salivary nucleus Intermediate part of facial nerve (CN VIIa) Geniculate ganglion Greater petrosal nerve Pterygopalatine ganglion Pathway divides into A. and B. CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 18 - ~ P ~ V Fig. 1-15. Branches of CN VII Arterial supplay of facial nerve: a. facial canal part: superficial petrosal branch of middle meningeal artery stylomastoid branch b. extratemporal part: stylomastoid artery posterior auricular artery superficial temporal artery transverse facial artery CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 19 6. Parotid gland Parotid gland (glandula parotidea) is the use largest salivary gland. The parotid gland occupies a depression between the mastoid process, the sternocleidomastoid muscle, and the ramus of num the mandible. It has two processes: m a. super ficia l facial process (accessory parotid) surrounds the proximal part of the parotid duct. b. deep process also called the retromandibular process which is roughly quadrilateral in shape. Parotid duct (ductus parotideus) - 5 cm long, 5 mm in diameter -nummm emerges from the facial process to continue across the masseter muscle, it passes through the suctorial fat pad (corpus us nu mmmun adiposum of the cheek) and pierces the buccinator muscle. It terms inside thevestibule of the mun mouth opposite to the upper 2nd molar tooth. mission The parotid capsule Two layers of the parotid fascia form the parotid capsule (camera glandulae parotis). It is an su extension of the superficial (subcutaneous) layerof the cervical fascia into the face that m provides a superficial and a deep layer (lamina) on the parotid gland. The superficial layer covers the subcutaneous surface of the parotid gland and extending superiorly, m it attaches to u the zygomatic arch. mu The superficial layer (lamina superficialis) of parotid fasciam blends with the masseteric fascia and with the platysma muscle along the anterior border of the gland. mu The deep layer (lamina profunda) of the parotid fasciamission fuses with the fascial cover of the posterior belly of the digastric muscle and attaches to the styloid process. Posteriorly, the ~ ~ deep layer splits to enclose the sternocleidomastoid muscle. num RELATIONS OF THE PAROTID GLAND The parotid gland is located: anterio rly : medial pterygoid and masseter muscles and the ramus of the mandible poste rio rly: mastoid process, sternocleidomastoid, and the post. belly of the digastric muscle medially: styloid process, stylohyoid, styloglossus and stylopharyngeus muscles, and the stylo-mandibular ligament latera lly: parotid fascia above: the zygomatic arch and the external auditory meatus below: parotid fascia Through the parotid gland pass the following structures started from lateral to medial: a. CN VII. It splits into its temporofacial and cervicofacial divisions within the gland and the mu buccal branches of both divisions anastomose roughly anteriorly to the isthmus of the gland (parotid plexus). b. retromandibular vein (formed by the union of the superficial temporal and maxillary veins) ~ descends through the gland slightly superficial to the external carotid artery. c.ECA (external carotid artery) which is located deep to the gland. 1. posterior auricular artery 2. superficial temporal artery 3. maxillary artery and also: d. transverse facial artery (branch of superficial temporal) use CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd 20 e. auriculotemporal nerve is find und deep to the posterior aspect of the parotid gland, between the external acoustic meatus and the condyle of the mandible. f. superficial and deep parotid lymphatic lymph nodes Innervation of the parotid gland The parotid gland is supplying by the: 1. auriculotemporal branch of CN V3, which provides sensory filaments to the parotid gland directly and general visceral efferent motor (postganglionic parasympathetic) fibres from the otic ganglion of CN IX to the gland 2. external carotid plexus (fibres travelling with the blood vessels) provides sympathetic postganglionic (vasoconstrictor) fibres to the gland. The cell bodies of these fibres are located in the superior cervical ganglion. Blood supply and lymphatic drainage Blood supply, venous drainage, and the lymphatic drainage of the parotid gland includes following vessels: a. Arteries from the external carotid artery via three major branches: 1. posterior auricular artery 2. superficial temporal artery 3. transverse facial artery b. Veins: drain primarily into the retromandibular system of veins. c. Lymphatic: the superficial and deep parotid nodes drain into the superficial and deep cervical nodes. 7. Clinical Notes SCALP LESION: A cut on the scalp bleeds more than elsewhere in the body due to the LCT holding the tissue open. This is normally fixed with stitches BELL'S PALSY: Paralysis of the Facial Nerve 1. Commonly occurs if the nerve is damaged or inflamed at the stylomastoid foramen. 1. Facial paralysis results on the side affected. Patients will be unable to close eyelids, they will drool, and they will have a contorted face 2. Loss of buccinator muscle can lead to difficulty eating and also restricts the closing of the eye causing drying and ulceration. The facial nerve weakness gives the: fattering of nasolabial groove slower blinking loss of facial wrinkles Damage of the: Temporal branch – raise the eyebrows, wrinkle the brow Zygomatic – close the eyes closed while examinated atteps to open them Buccal – smile, show teeth, puff out the cheeks Mandibular – pout, purse the lips Cervical - sneer CLINICAL ANATOMY OF THE HEAD - J. Gielecki and A. urada Copyright © 2010 MedRadEd