Skull and Face Boonsirm Withyachumnarnkul, M.D., Ph.D. Department of Anatomy, Faculty of Science Mahidol University

Bony Landmarks of Skull and Face Vertex Superciliary arch Zygoma Mental symphysis Entrance to orbit Anterior nasal aperture

Three foramina vertically alligned Supraorbital foramen … for supraorbital nerve Infraorbital foramen … for infraorbital nerve Mental foramen ... for mental nerve

Muscles of Facial Expression Develop from the 2nd branchial arch, thus all are supplied by CN VII. Most are thin, originate from facial bones to insert on facial skin, except platysma, and are intermingled at their insertions.

Muscles of Facial Expression Muscle of the forehead … frontalis, as part of the occipitofrontalis Muscles of the mouth Muscle of the eyelids Muscle of the nose Platysma

Muscles of the Mouth Orbicularis oris Zygomaticus major Zygomaticus minor Levator labii superioris Levator labii superioris alaque nasi Buccinator Depressor anguli oris Depressor labii inferioris Mentalis Risorius Platysma

Muscles of the Mouth

Muscle of the Eyelids Orbicularis oculi Orbital part Palpebral part

Buccal Pad Fat Between masseter and buccinator muscles Brown fat … for heat generation, especially for children

Parotid Duct One finger-breadth below zygomatic arch Open into the mouth cavity (vestibule) at the level of the 2nd molar tooth (crown)

Facial Nerve Comes out from stylomastoid foramen Five branches Temporal Zygomatic Buccal Mandibular Cervical

Facial Palcy No wrinkle of forehead Angle of mouth drops Sagging lower eyelid Other signs relating to malfunctions of structures innervated by facial nerve

Trigeminal Nerve Sensory Ophthalmic division Maxillary division Mandibular division Motor .. To 1st branchial arch Muscles of mastication Messeter Temporalis Medial pterygoid Lateral pterygoid

Arteries of the Face (rich, tortuous and highly anastomosed) From external carotid artery Facial artery Superficial temporal artery Transverse facial artery From internal carotid artery supraorbital artery supratrochlear artery

Veins of the Face Two important veins Facial veins have no valves Retromandibular vein Facial veins have no valves Connection of facial veins, pterygoid plexus and cavernous sinus

Lymph Drainage of the Face Submental lymph nodes Submandibular lymph nodes Parotid lymph nodes

Scalp, Cranial Cavity and Venous Sinuses Boonsirm Withyachumnarnkul, M.D., Ph.D. Department of Anatomy, Faculty of Science Mahidol University Head2.ppt in C (Mahidol)

Scalp Five layers of scalp skin dense subcutaneous tissue epicranial aponeurosis loose areolar connective tissue periosteum

Scalp Clinical relevance infection spreading from loose areolar connective tissue, via emissary veins, to meninges-meningitis hematoma

Skull Cap or Calvaria Suture coronal (frontoparietal) anterior fontanelle sagittal (interparietal) lambdoid (occipitoparietal) posterior fontanelle

Skull Cap or Calvaria Three layers of skull cap outer table diploe inner table

Cranial Fossae Anterior cranial fossa Middle cranial fossa Posterior cranial fossa Boundaries lesser wing of sphenoid superior border of petrous bone

Anterior Cranial Fossa important landmarks crista galli & cribriform plate of ethmoid sella turcica tuberculum sellae hypophyseal fossa dorsum sellae

Middle Cranial Fossa important landmarks foramina groove for middle superior orbital fissure foramen rotundum foramen ovale foramne spinosum groove for middle meningeal artery

Posterior Cranial Fossa important landmarks grooves for transverse & sigmoid sinuses foramen magnum

Dura Mater Outer and inner layers position of the middle meningeal artery

Dura Mater Falx cerebri Falx cerebelli Tentorial cerebelli and notch Diaphragmatic sellae

Intradural Venous Sinuses Superior and inferior sagittal sinuses Straight sinus Transverse and sigmoid sinuses

Intradural Venous Sinuses Cavernous sinus relationship among internal carotid artery, CN III, CN IV, CN V1 and CN VI venous connections clinical relevance thrombophlebitis

Orbit and Eye Boonsirm Withyachumnarnkul, M.D., Ph.D. Department of Anatomy, Faculty of Science Mahidol University

Eye From the Outside eyelids palpebral fissure plica semilunaris caruncle lacrimal puncta cornea sclera conjunctiva bulbar palpebral Sty pterygium

Bony Parts of the Orbit Entrance of the Orbit frontal bone zygomatic bone maxillary bone More Bones Inside ethmoid bone greater and lesser wing of sphenoid lacrimal bone

Foramina of the Orbit optic foramen (canal) optic n. ophthalmic a. superior orbital fissure all other nerves superior ophthalmic vein inferior orbital fissure infraorbital n. & a. inferior ophthalmic v. infraorbital groove & foramen zygomatic & infraorbital n. supraorbital notch & foramen supraorbital n.

Eyeball

Eyeball Muscles Extrinsic (Extra-ocular) Intrinsic

Levator Palpebrae Superioris Supplied by CN III insert on the upper lid if paralyzed ptosis

Extra-Ocular Muscles Superior Rectus Inferior Rectus Lateral Rectus Medial Rectus Superior Oblique Inferior Oblique

Actions of the Extra-Ocular Muscles Around vertical axis medial or adduction lateral or abduction Around horizontal axis upward or elevation downward or depression Around antero-posterior axis medial rotation lateral rotation

Superior Rectus Make a 10-15 o with an AP axis adduct medial rotate elevate

Inferior Rectus depress adduct lateral rotate

Medial and Lateral Recti Medial Rectus adduction Lateral Rectus abduction

Superior Oblique depress abduction medial rotate

Inferior Oblique elevate abduction lateral rotate

Periorbita and Orbital Fat

Insertions of the Extra-Ocular Muscles

Nerves of the Extra-Ocular Muscles Oculomotor Nerve (CN III) supplies all except lateral rectus and superior oblique Trochlear Nerve (CN IV) superior oblique Abducens Nerve (CN VI) lateral rectus

Oculomotor nerve (CN III) Superior Division levator palpebrae superioris* superior rectus Inferior Division inferior rectus inferior oblique medial rectus *not an extra-ocular muscle

Functional Tests of the Extra-Ocular Muscle Principle align the muscle axis with the eyeball AP axis contract the muscle e.g., for Superior Rectus abduct, first then, elevate Therefore, test for the superior rectus function is to abduct and elevate

Parts of the Eyeball Three layers sclera choroid retina anterior chamber posterior chamber cornea iris ciliary muscle suspensory ligament lens hyaloid canal vitreous body aqueous humor

Clinical Relevance lenticular cataract glaucoma Schlemn’s canal Myopia (near sightedness) hyperopia (far sightedness) presbiopia (old-aged sightedness)

Blood Vessels of the Orbit & Eyeball Ophthalmic Frontal anterior & posterior ethmoidal supraorbital supratrochlear lacrimal central retinal in the choroid layer

Ophthalmoscopic Examination optic disc macula lutea & fovea centralis retinal vessels in DM & hypertension

Veins of the Eyeball superior & inferior ophthalmic veins drained to cavernous sinus connection to pterygoid plexus connection to facial veins

Sensory Nerves of the Eyeball and Orbit frontal supraorbital supratrochlear lacrimal nerve nasociliary nerve anterior ethmoidal posterior ethmoidal infratrochlear

Autonomic Nerves of the Eyeball and Orbit Sympathetic post-ganglionic sympathetic fibers artery (ophthalmic a) long ciliary n. eyeball iris (radial fibers) Parasympathetic pre-ganglionic parasympathetic fibers (in the nerve to inferior oblique) ciliary ganglion short ciliary n. Eyeball ciliary muscle & iris (circular fibers)

Ciliary Ganglion

Lacrimal Gland and Lacrimal Apparatus Lacrimal puncta lacrimal canaliculi lacrimal sac nasolacrimal duct opening into the inferior meatus of nasal cavity

Parasympathetic Supply to the Lacrimal Gland Preganglionic parasympathetic fibers pterygopalatine ganglion maxillary n zygomatic branch zygomatico-temporal branch lacrimal n lacrimal gland

Eyelid upper & lower eyelids conjunctiva palpebral fissure & palpebral sac tarsal plates (superior & inferior) tarsal muscle & nerve (sympathetic n) tarsal gland & ciliary gland; Meibomitis & sty attachment of levator palpebrae superioris

Orbital Septum, Medial & Lateral Palpebral Ligament

Submandibular Region, Nasal Region and Oral Cavity Boonsirm Withyachumnarnkul, M.D., Ph.D. Department of Anatomy, Faculty of Science Mahidol University Head 6. ppt in C (Mahidol)

Submandibular Region Inferior border of mandible Suprahyoid muscles Including submandibular triangle Submandibular gland Nerves lingual hypoglossal mandibular branch of CN VII Blood vessels facial Lymph nodes, submandibular lymph nodes

Submandibular Triangle Anterior belly of digastric muscle Origin, digastric fossa of mandible Nerve, nerve to mylohyoid (CN V) Posterior belly of digastric muscle Origin, mastoid notch Nerve, CN VII Inferior border of mandible

Actions of Digastric Muscle Elevate hyoid bone Open jaw Raising floor of mouth for swallowing reflex

Suprahyoid Muscles Digastric Mylohyoid Geniohyoid Hyoglossus Stylohyoid

Mylohyoid Muscle Origin, mylohyoid line of mandible Insertion Body of hyoid bone Median fibrous raphe Nerve, nerve to mylohyoid (CN V)

Geniohyoid Muscle Origin, mental spine Insertion, hyoid bone Nerve, C1 spinal nerve

Hyoglossus Muscle From hyoid bone to side of the tongue Nerve, hypoglossal nerve

Stylohyoid Muscle Origin, styloid process Insertion, hyoid bone (two slips) Nerve, CN VII

Concerted Action of Suprahyoid Muscles Elevate floor of mouth for swallowing reflex

Submandibular Gland superficial part deep part the two parts are separated by mylohyoid muscle mixed serous and mucous gland submandibular duct from deep part open at sublingual caruncle

Anatomical Relationship Hypoglossal and lingual nerves are between mylohyoid and hyoglossus muscles Closed relationship between lingual nerve and submandibular duct

Chorda tympani special sense (taste) from anterior 2/3 of tongue preganglionic parasympathetic fibers to submandibular and sublingual gland, via submandibular ganglion

The Nasal Region Nostrils Vestibule Nasal cavity Choanae Nasal septum Cartilage, septal cartilage Bone perpendicular plate of ethmoid vomer maxillary & palatine

Lateral Wall of the Nasal Cavity Chonchae superior, part of ethmoid middle, part of ethmoid inferior, separate bone

Lateral Wall of the Nasal Cavity Meatuses sphenoethmoidal recess, opening of sphenoidal sinus superior, opening of posterior ethmoidal air cells middle bulla ethmoidalis, opening of middle ethmoidal air cells hiatus semilunaris, opening of maxillary sinus anterior ethmoidal air cells frontal sinus, infundibulum inferior, opening of nasolacrimal duct common meatus

Nerves of the Nasal Cavity Special sense, olfactory n. "olfactory mucosa" General sense, "respiratory mucosa" branch of nasociliary n. anterior ethmoidal n. branches of maxillary n. nasopalatine n. posterior superior lateral nasal n. posterior inferior lateral nasal n. Test of olfactory function

Third Part of the Maxillary Artery superior alveolar a. posterior anterior, from infraorbital a. infraorbital a. descending palatine a. greater palatine a. lesser palatine a. sphenopalatine a.

Blood Supply of the Nasal Cavity from sphenopalatine a. posterior lateral nasal br. posterior septal br. from ophthalmic a. anterior and posterior ethmoidal a

Paranasal Air Sinuses Locations frontal sinuses ethmoidal air cells posterior middle anterior sphenoidal sinuses maxilary sinus Functions warm and humidify air resonance

Maxillary Nerve out of the skull through foramen rotundum branches zygomatic n. zygomaticotemporal n. zygomaticofacial n. infraorbital n., out from the infraorbital foramen superior alveolar n.; anterior, middle, posterior two small br. to pterygopalatine ganglion

Pterygopalatine Ganglion pterygopalatine br. from maxillary n., general sense nerve of pterygoid canal parasympathetic sympathetic Out pterygopalatine br. to maxillary n., parasympathetic fibers to lacrimal gland pharyngeal n. greater and lesser palatine n. superior and inferior lateral nasal n. nasopalatine n

Pterygopalatine Ganglion All the "out" branches supply submucosal gland, parasympathetic general sense lacrimal gland, parasympathetic

Mouth & Lips vestibule oral cavity proper nasolabial sulcus philtrum labial gland frenulum palatoglossal arch palatopharyngeal arch opening of parotid duct opening of submandibular & sublingual ducts

The Teeth Types incisor, 2 canine, 1 premolar, 2 molar, 3 Nerves and vessels (to teeth and gingivae) alveolar superior (maxillary n. and a.) anterior middle posterior inferior (mandibular n., maxillary a.) nasopalatine (maxillary n. and a.) greater palatine (maxillary n. and a.)

The Tongue sulcus terminalis foramen caecum papillae circumvallate fungiform filiform foliform lingual tonsil

Muscles of the Tongue Intrinsic longitudinal transverse vertical Extrinsic hyoglossus genioglossus (movement of tongue) styloglossus palatoglossus

Artery & Nerves of the Tongue lingual a. Nerves motor, hypoglossal n., except palatoglossus (vagus n.) sensory general, CN V, IX & X special, CN VII (anterior 2/3) & CN IX (posterior 1/3), CN X

The Palate Hard palate Soft palate, muscles Clinical relevant tensor veli palatini (CN V) levator veli palatini (CN X) musculus uvulae (CN X) palatoglossus (CN X) palatopharyngeus (CN X) Clinical relevant openning of auditory tube test of CN X

Blood Supply of Palatine Tonsil (important for tonsillectomy) from lingual a. dorsal lingual a. from facial a. tonsillar br. ascending palatine a. from ascending pharyngeal a. palatine br. lesser palatine a.