Head-Neck Anatomy Handout - Dr. Malanog - PDF

EXPERTMD MEDICINE BOARD REVIEW ANATOMY – HEAD & NECK Lecturer: John Paulo Malanog, OTRP, MD HEAD, NECK & VERTEBRAL COLUMN OUTLINE A. Scalp B. Skull C. Vertebrae D. Face E. Neck F. Blood Vessels of the Head & Neck...

EXPERTMD MEDICINE BOARD REVIEW ANATOMY – HEAD & NECK Lecturer: John Paulo Malanog, OTRP, MD HEAD, NECK & VERTEBRAL COLUMN OUTLINE A. Scalp B. Skull C. Vertebrae D. Face E. Neck F. Blood Vessels of the Head & Neck CRANIAL SUTURE Coronal suture Between frontal bone and two parietal A. SCALP bones Sagittal suture Between two parietal bones Squamous/ Between parietal bone and squamous Squamoparietal part of temporal bone suture Lambdoid Between two parietal bones and suture occipital bones JUNCTIONS OF CRANIAL SUTURES Intersection of the sagittal and coronal sutures Bregma In infants, this structure was the anterior fontanel which closed at 18 months Intersection of the lambdoid and sagittal sutures LAYERS OF THE SCALP Lambda In infants, this structure was the Thick posterior fontanel which closed at first Skin few months Contains sebaceous glands Insertion of muscles Intersection frontal, parietal, temporal, Pterion and the greater wing of sphenoid Connective Dense subcutaneous tissue Injury at this area may rupture the Tissue Contains blood vessels and nerves, sweat middle meningeal artery glands and hair follicles A craniometric point at the junction of Galea aponeurotica/ Asterion the parietal, occipital, and temporal Epicranial aponeurosis (mastoid part) bones Tendinous sheet that covers the vault of Aponeurosis Nasion Intersection of the frontal and two nasal the skull bones Unites the occipital and frontal bellies of Inion Most prominent point of the external the occipitofrontal muscles occipital protuberance Forms the loose and scanty Used as a fixed point in craniometry subaponeurotic spaces Loose Contains the emissary veins Connective Termed as the dangerous area because Tissue infection can easily spready in it or from the scalp to the intracranial sinuses by way of the emissary veins Pericranium/ Hematoma may form underneath but Periosteum limited to each bone Innervation: supratrochlear, supraorbital, zygomaticotemporal, auriculotemporal, lesser occipital, greater occipital, and third occipital nerves Blood supply: o supratrochlear and supraorbital branches of the internal carotid artery o superficial temporal, posterior auricular, and occipital branches of the external carotid artery B. SKULL/ CRANIUM SKULL FRACTURE SKULL BASE FRACTURE Battle sign (postauricular ecchymosis) Halo sign (CSF discharge from rhinorrhea, otorrhea) Racoon eyes (periorbital edema and ecchymosis) LE FORT FRACTURES Le Fort I: horizontal fracture superior to maxillary alveolar process Le Fort II: posterolateral parts of the maxillary sinuses; central part of the face separated from cranium Le Fort III: horizontal fracture that passes through the PAIRED UNPAIRED superior orbital fissures, ethmoid and nasal extending to FACIAL BONES (14) greater wing of sphenoid; maxillae and zygomatic Lacrimal separated from cranium Nasal Palatine Mandible Maxillary Vomer Zygomatic Inferior Nasal Concha CRANIAL BONES (8) Frontal Parietal 📌 Occipital Temporal Ethmoid Sphenoid MVPT 1  BONE OF TRANSMITTED FORAMENA IN FRONT OF THE SKULL SKULL STRUCTURES Supraorbital nerve, artery, vein ANTERIOR CRANIAL FOSSA Supraorbital Branch of the Frontal nerve from the Cribriform Ethmoid Olfactory nerve bundles foramen Ophthalmic division of Trigeminal plate nerve (V1) Foramen Emissary veins from nasal mucosa to superior sagittal Infraorbital Infraorbital branch of the Maxillary cecum foramen Nerve (V2) sinus Crista galli Ethmoid Provides attachment for falx Branches of the Inferior Alveolar nerve cerebri Mental foramen (mental nerve) and vessels MIDDLE CRANIAL FOSSA Found adjacent to the root of the Optic nerve (CN II) mandibular 2nd premolar tooth Optic canal Lesser wing Ophthalmic artery Mandibular branch of the Trigeminal of sphenoid Central artery/vein of the Mandibular nerve (CN V3) retina foramen Inferior alveolar nerve and Oculomotor nerve (CN III) Inferior alveolar artery/vein Between Trochlear nerve (CN IV) Zygomaticofacial Zygomaticofacial nerve Superior lesser and Lacrimal, Frontal and foramen orbital greater wing Nasociliary branches of fissure of sphenoid Ophthalmic nerve (CN V1) FORAMENA IN THE BASE OF THE SKULL Abducens Nerve (CN VI) Petrotympanic Chorda tympani Superior Ophthalmic Vein fissure Anterior tympanic artery Foramen Greater wing Maxillary nerve (CN V2) Facial nerve rotundum of sphenoid Stylomastoid artery (Posterior Mandibular nerve (CN V3) Stylomastoid Auricular from External Carotid Artery) Foramen Greater wing Accessory Meningeal artery foramen Found between the styloid and ovale of sphenoid Lesser petrosal nerve mastoid processes of the temporal (occasionally) bone Foramen Greater wing Middle Meningeal artery/vein Nasopalatine nerve spinosum of sphenoid Meningeal branch of Incisive canal Terminal part of sphenopalatine or mandibular nerve greater palatine vessels Between Traversed by ICA, greater Greater palatine Greater palatine nerve and vessels Foramen petrous part and deep petrosal nerves foramen lacerum of temporal Lesser palatine Lesser palatine nerve and vessels and foramen sphenoid Internal Carotid Artery Palatine canal Descending palatine vessels Carotid Greater and lesser palatine nerves Canal Sympathetic nerves (carotid plexus) Runs from the anterior wall of the Hiatus of Greater petrosal nerve foramen lacerum to the facial canal Pterygoid canal pterygopalatine fossa POSTERIOR CRANIAL FOSSA Nerve of the pterygoid canal (Vidian Facial nerve (CN VII) nerve) Internal acoustic Petrous part Vestibulocochlear nerve (CN Sphenopalatine Sphenopalatine vessels of temporal VIII) foramen Nasopalatine nerve meatus Labyrinthine artery Inferior petrosal sinus C. VERTEBRAE Glossopharyngeal nerve (CN Consists of 33 vertebral bones (7 cervical, 12 thoracic, 5 Between IX) lumbar, 5 fused sacral, 4 fused coccygeal) Jugular petrous part Vagus nerve (CN X) Separated by intervertebral discs foramen of temporal Accessory nerve (CN XI, and occipital Primary curvature: cranial root) o thoracic and sacral regions Sigmoid sinus o concave ventrally Posterior Meningeal artery Secondary curvature: Hypoglossal Occipital Hypoglossal nerve (CN XII) o cervical and lumbar regions canal o convex ventrally Accessory Nerve (CN XI, spinal root) Medulla oblongata Meninges Foramen Occipital Spinal cord magnum Vertebral arteries Venous plexus of vertebral canal Anterior/posterior spinal arteries Condyloid Condyloid emissary veins foramen Branch of occipital artery to Mastoid dura mater and mastoid Foramen emissary vein ABNORMAL CURVATURES KYPHOSIS Abnormal increased thoracic (forward) curvature resulting from osteoporosis LORDOSIS Abnormally increased lumbar (backward) curvature resulting from trunk muscle weakness or osteomalacia SCOLIOSIS Lateral deviation resulting from unequal growth of the vertebral column, pathologic erosion of vertebral bodies, or asymmetric paralysis or weakness of vertebral muscles 2  Thoracic and lumbar roots exit BELOW the vertebra of ANATOMIC LANDMARKS the corresponding number (L4 nerve root exits between VERTEBRAL ANATOMIC STRUCTURES L4-L5 vertebra) LEVEL In posterolateral herniation* (paracentral), the nerve C3 – C4 Hyoid bone root compressed is the level below Bifurcation of common carotid artery o Example: If there is a posterolateral herniation of C5 Thyroid cartilage the disk at L4 to L5, the nerve root compressed is Carotid pulse palpated L5. C6 Cricoid cartilage In lateral herniation, the nerve root compressed is the Start of trachea level above Start of esophagus o Example: If there is a posterolateral herniation of the disk at L4 to L5, the nerve root compressed is T2 Sternal notch L5. Superior angle of scapula Arch of aorta T4 Sternal angle Junction of superior & inferior mediastinum Bifurcation of trachea T5 – T7 Pulmonary hilum T8 Inferior vena cava hiatus T9 Xiphisternal joint T10 Esophageal hiatus Tip of xiphoid process T12 Aortic hiatus Celiac artery Upper pole of left kidney T12 – L1 Duodenum L1 Superior mesenteric artery Upper pole of right kidney TYPICAL VERTEBRA End of spinal cord in adult (conus medullaris) and pia mater L2 Renal artery L3 End of spinal cord in newborn Inferior mesenteric artery Umbilicus L4 Iliac crest Bifurcation of aorta S1 Sacral promontory S2 End of dural sac, dura, arachnoid, subarachnoid space and CSF S3 End of sigmoid colon INTERVERTEBRAL DISC Acts as shock-absorbing mechanism by equalizing pressure Avascular, except for their peripheries Allows movement between vertebrae A. BODY It is a short cylinder that supports weight A. NUCLEUS PULPOSUS Separated and bound together by intervertebral disks Remnant of the notochord ⋆ Costal facets/processes of the thoracic vertebrae: Situated in the central portion of the IV disc located anterior to the pedicles which articulate with May herniate through the annulus fibrosus, commonly the heads of the corresponding ribs and the ribs just occurring posterolaterally below B. ANNULUS FIBROSUS B. VERTEBRAL ARCH Binds the vertebral column together Consists of paired pedicles laterally and paired Retains the nucleus pulposus laminae posteriorly Permits limited movement Forms the vertebral foramen with the vertebral body and protects the spinal cord and associated structures C. PROCESSES ASSOCIATED WITH VERTEBRAL ARCH 1. Spinous Process Projects posteriorly from the junction of 2 laminae of the vertebral arch 2. Transverse Processes Projects laterally on each side from the junction of the pedicle and the lamina Articulates with the tubercles of ribs 1 to 10 in the thoracic region INTERVERTEBRAL DISC HERNIATION In the cervical region, (+) transverse foramina 3. Articular Processes (Facets) CERVICAL DISC HERNIATION Two superior and two inferior projections from Most commonly affected: C5-C6 or C6-C7 the junction of the laminae and pedicles Cervical roots exit ABOVE the vertebra of the Articulates with other articular processes of the corresponding number (C6 exits between C5-C6 arch above or below, forming a plane synovial vertebra) joint Exemption: Between C7-T1 vertebra, the nerve root 4. Mamillary Processes that exits is C8 (not T1) Tubercles on the superior articular processes of the lumbar vertebrae LUMBAR DISC HERNIATION 5. Accessory Processes Most commonly affected: L4-L5, L5-S1 Project backward from the base of the transverse process and lateral and inferior to the mamillary process of a lumbar vertebra 3 D. FORAMINA ASSOCIATED WITH VERTEBRAL ARCH 1. Vertebral foramina Vertebral bodies + vertebral arches = v. canal Transmit the spinal cord & associated structures 2. Intervertebral foramina Between the inferior and superior surfaces of the pedicles of adjacent vertebrae Transmit the spinal nerves and accompanying vessels as they exit the vertebral canal 3. Transverse foramina Present in the transverse processes of the CERVICAL VERTEBRAE cervical vertebrae Atypical cervical vertebrae Transmit the vertebral artery (except for C7), Supports the skill vertebral veins and autonomic nerves Widest Consists of anterior & posterior arches and First paired transverse processes VERTEBRAL COLUMN PATHOLOGIES Cervical No body, no spine (Atlas) Articulate with occipital condyles of skull to SPONDYLITIS Inflammation of the vertebra form atlantooccipital joint Ankylosis Spondylitis is a form of rheumatoid arthritis Articular with axis of C2 to form atlantoaxial that affects the vertebral joints, especially lower back. joints for neck flexion-extension ⋆ Produces pain stiffness, swelling and limited motion. Jefferson fracture: burst fracture of the atlas The affected vertebrae fuse or grow together, resulting Atypical cervical vertebrae in a rigid spine (bamboo spine deformity), poor posture Smallest transverse processes and deformities. Second Odontoid process/ Dens: articulates Cervical superiorly with the anterior arch of the atlas SPONDYLOSIS (Axis) that forms the pivot atlantoaxial joint, which Ankylosis of the vertebra allows rotatory movement ⋆ Degenerative osteoarthritis of the vertebral joints Hangman’s Fracture: fracture of the Causes pressure on nerve roots à pain and weakness pedicles of C2 Third to Typical cervical vertebrae: short bifid spinous SPONDYLOLYSIS Sixth processes and transverse processes with Stress fracture through the pars interarticularis of the Cervical anterior and posterior tubercles and lumbar vertebra transverse foramina (+) transverse foramina: transmit vertebral SPONDYLOLISTHESIS artery Forward displacement of one vertebra over another Atypical cervical vertebrae Usually, L5 over the body of the sacrum, or L4 over L5 Seventh Long spinous process but not bifid, nearly Cervical horizontal POTT’S DISEASE Attachment side for ligamentum nuchae, TB of the spine or vertebra that results from softening supraspinous ligaments and back muscles and collapse of the vertebrae, often causing kyphosis THORACIC VERTEBRAE Most commonly localized in the thoracic area Medium (heart-shaped) bodies Symptoms: paravertebral swelling or abscess (causing ⋆ Superior costal facet articulates with head of the spinal cord compression), paraplegia, back pain, fever, corresponding rib cough, sweats, anorexia and weight loss. ⋆ Inferior costal facet articulates with head of rib below ⋆ Transverse process articulates with tubercles of REGIONAL CHARACTERISTICS OF corresponding rib VERTEBRAE Long spinous processes LUMBAR VERTEBRAE Large (kidney-shaped) bodies and transverse process, sturdy laminae, absent costal facets, presence of mamillary and accessory processes Long spinous processes 5th lumbar vertebrae: largest body SACRUM large, triangular, wedge-shaped Four pairs of foramina for exit of the ventral and dorsal primary rami of the 1st four sacral nerves Forms part of the pelvis posteriorly for pelvic strength and stability Features: promontory (S1), ala, median sacral crest, sacral hiatus, sacral cornu COCCYX Wedge-shaped bone Attachment for coccygeus and levator ani muscles LIGAMENTS OF VERTEBRAL COLUMN A. Anterior Longitudinal Ligament Occipital bone à sacrum on the anterior surface of vertebral bodies and IV disks Limits extension of vertebral column B. Posterior Longitudinal Ligament Supports posterior aspect of vertebral bodies Runs anterior to the spinal cord within the vertebral canal Limits flexion C. Ligamentum Flavum Maintains upright posture Connects laminae of two adjacent vertebrae Forms posterior wall of vertebral canal between the vertebrae 4 D. Ligamentum Nuchae Triangular-shaped medial fibrous septum between the muscles on the two sides of the posterior aspect of neck E. Other Ligaments: 1. Interspinous: between 2 adjacent spinous processes 2. Intertransverse: between 2 adjacent transverse processes 3. Supraspinous: between tips of 2 adjacent spinous processes LUMBAR PUNCTURE Within an imaginary line between the highest points of the iliac crest Done above or below L4 LAYERS TRAVERSED Skin Superficial fascia Supraspinous ligament Interspinous ligament Ligamentum flavum Epidural space Dura mater Arachnoid mater MUSCLES OF MASTICATION Subarachnoid space (+) CSF From the 1st branchial arch Innervation: Mandibular Branch of CN V D. FACE OPENS JAW CLOSES JAW MUSCLES OF FACIAL EXPRESSION (ELEVATES) (DEPRESSES) Mesoderm in origin in the 2nd pharyngeal arches Temporalis Muscles are attached to bone or fascia Masseter Lateral Pterygoid Innervation: Facial Nerve (CN VII) Medial Pterygoid Occipitofrontalis Surprise Elevates eyebrows, wrinkles forehead Corrugator supercilli Anger, frowning Draws eyebrows downward, medially Orbicularis oculi Wink Closes eyelid Procerus Sadness Wrinkles skin over bones Nasalis Compress nostril (transverse part) NERVE SUPPLY TO THE FACE Dilates nostril (alar part) Depressor Septi Constricts nares TRIGEMINAL NERVE Orbicularis oris Kissing Anterior division is motor, posterior division is sensory Closes lips or purse SENSORY: Skin of the face; Anterior 2/3 of tongue (common sensation) Levator anguli oris Disgust MOTOR: Muscles of mastication Elevates angle of mouth medially Muscles of floor of the mouth (anterior belly of Levator labii Disgust digastric, mylohyoid, tensor veli palatini, tensor superioris Elevates upper lip; dilates nares tymani) Levator labii superioris alaeque Elevates ala of nose and upper lip Exits through the superior orbital fissure nasi Sensory: above the upper eyelid and tip Zygomaticus major Smile of the nose Draws angle of mouth backward, V1: Branches: supraorbital, supratrochlear, upward OPHTHALMIC infratrochlear, external nasal, lacrimal Zygomaticus minor Elevates upper lip nerves Depressor labii Depresses lower lip Exits through the foramen rotundum inferioris V2: Sensory: below the level of the eyes and Depressor anguli Frowning MAXILLARY above the upper lip oris Depresses angle of mouth Branches: zygomaticofacial, zygomaticotemporal, infraorbital nerves Risorius Grimace Exits through the foramen ovale Retracts angle of mouth V3: Sensory: below the level of lower lip; Buccinator/ Blowing, Sucking MANDIBULAR somatic innervation from anterior 2/3 of Trumpeter’s Muscle Compresses check to keep it taut tongue Mentalis Doubt Branches: auriculotemporal, buccal, Elevates and protrudes lower lip mental nerves Auricular anterior, Retract and elevates ear superior, posterior 5 FACIAL NERVE MUSCLES OF EYE MOVEMENT SENSORY: Anterior 2/3 of tongue (taste sensation); MUSCLE ORIGIN INSERTION NERVE ACTION External ear (common sensation) Superior Elevates MOTOR: Muscles of facial expression; stylohyoid and rectus Intorts Inferior Common Sclera just CN III Depress posterior belly of digastic rectus tendinous behind Extort Secretomotor to lacrimal ⋆, submandibular and sublingual Medial ring ⋆ cornea Adduct glands rectus Efferent limb of the corneal blink reflex (afferent is CN V1) Lateral CN VI Abduct Exits from the stylomastoid foramen and enters the parotid rectus gland to give rise to fiver terminal branches that radiate Body of Sclera forward in the face Superior sphenoid beneath Intort oblique above superior CN IV Depress, optic rectus Abduct Greater Secretomotor: lacrimal gland canal Petrosal Arise from geniculate ganglion Floor of Nerve to Prevents hyperacusis (dampens vibrations of Inferior orbit Sclera Extort Stapedius the stapes) oblique lateral to beneath CN III Elevate, Secretomotor: submandibular and sublingual lacrimal lateral rectus Abduct Chorda groove glands Lesser Tympani TASTE sensation: anterior 2/3 of tongue and wing of floor of mouth Levator sphenoid Tarsal plate CN III, Elevates Auricle, external auditory meatus, tympanic palpebrae above and skin of sympathetic upper Posterior superioris and upper eyelid eyelid membrane, posterior belly of digastric, Auricular anterior to stylohyoid optic Temporal, zygomatic, buccal, mandibular, canal Terminal and cervical branches Branches Located between the superficial and deep lobes of the parotid gland EYES BONY ORBIT MARGINS OF THE ORBIT Superior Frontal Lateral Frontal, zygomatic Inferior Zygomatic, maxilla Medial Maxilla, frontal LACRIMAL APPARATUS WALLS OF THE ORBIT A. LACRIMAL GLAND Superior wall/ Orbital part of frontal bone Lies in upper lateral region of the orbit on the lateral Roof Lesser wing of sphenoid rectus and levator palpebrae superioris Lateral wall Frontal process of zygomatic bone Tears à drained by 12 lacrimal ducts à superior Greater wing of sphenoid conjunctival fornix Inferior wall/ Floor Orbital surface of maxilla, zygomatic B. LACRIMAL CANALICULI and palatine bones Two curved canals that begin as a lacrimal Medial wall Orbital plate of ethmoid, frontal, punctum/pore in the margin of the eyelid and opens lacrimal and sphenoid bones into the lacrimal sac OPENINGS OF THE ORBIT C. LACRIMAL SAC Optic canal Optic nerve The upper dilated end of the nasolacrimal duct, which Ophthalmic artery opens into the inferior meatus of the nasal cavity Supraorbital notch Supraorbital nerve and vessels Infraorbital notch Infraorbital nerve and vessels D. TEARS Nasolacrimal Nasolacrimal duct Pass through excretory ductules à superior canal conjunctival fornix, spread evenly over the eyeball by Superior orbital Lacrimal, nasociliary & frontal blinking and accumulate in the area of the lacrimal fissure nerves lake Trochlear, oculomotor, abducens Lacrimal canaliculi through puncta à lacrimal sac à nerve nasolacrimal duct à inferior nasal meatus Superior ophthalmic vein Inferior orbital Maxillary nerve and branches fissure Inferior ophthalmic vein Sympathetic nerves EYEBALL EXTERNAL WHITE FIBROUS COAT Sclera White fibrous tunic enveloping the posterior 5/6 of the eye Cornea Transparent structure forming the anterior 1/6 of the external coat ⋆ Layers: o Anterior Epithelium o Bowman’s membrane o Corneal stroma o Descemet’s membrane o Endothelium 6 MIDDLE VASCULAR PIGMENTED COAT Choroid Outer pigment layer, highly vascular VISUAL FIELD DEFECTS ⋆ Invests the posterior 5/6 of eyeball Nourishes the retina and darkens the eye Ciliary Body Thickened portion Found between the choroid and iris (+) ciliary ring, ciliary processes, ciliary muscle Iris Thin, contractile, circular, pigmented diaphragm with a central aperture (pupil) Circular muscle fibers (parasympathetic) and radial muscle fibers/dilator pupillae (sympathetic innervation) INTERNAL NERVOUS COAT Retina Layers: o Inner limiting membrane o Nerve fiber layer o Ganglion cell layer o Inner plexiform layer o Inner nuclear layer o Outer plexiform layer Pituitary gland by tumors expanding superiorly can o Outer nuclear layer compress the optic chiasm and cause bitemporal o External limiting membrane hemianpsia ⋆ o Photoreceptor layer Perimetry: measurement of visual field function ⋆ o Retinal pigment epithelium Optic Disk Optic nerve fibers formed by axons of the ganglion cells connected to the rods and cones by bipolar neurons ORAL CAVITY Located nasal/medial to the fovea Anterior and lateral boundary: teeth & gums centralis Roof: palate Insensitive to light; no receptors Floor: tongue and mucosa Macula Yellow spot/ Macula Lutea Supported by geniohyoid and mylohyoid Near the center of the retina on the Communicates posteriorly with the oropharynx temporal side of the optic disk Most distinct vision; contains the fovea ORAL VESTIBULE centralis bounded by lips and cheeks externally, teeth and gums Fovea Central depression in the macula internally Centralis Avascular Has cones only and functions in detailed vision Rods Most numerous Dim light Cones Most numerous in the foveal region Visual acuity and color vision REFRACTIVE MEDIA Cornea Aqueous Formed by the ciliary processes Humor Provides nutrients for the avascular cornea and lens Posterior chamber à anterior chamber à canal of Schlemm à scleral venous plexus at the iridocorneal angle Lens Transparent avascular biconvex Held in position radially by zonular fibers PALATE to the ciliary processes forms the roof of the mouth and floor of the nasal cavity Flattens to focus on distant objects by pulling zonular fibers A. HARD PALATE Becomes globular to accommodate the Consists of palatine process of maxillae and eye for near objects by contracting the horizontal plates of palatine bones ciliary muscles and relaxing zonular fibers Anterior 4/5 of the palate Vitreous Transparent gel that fills the eyeball Forms a bony framework covered with mucous Body posterior to the lens membrane between nasal and oral cavities Hold retina in place and provides support Innervation: greater palatine nerves and nasopalatine for the lens nerves Blood supply: greater palatine artery B. SOFT PALATE Posterior 1/5 of the palate Fibromuscular fold extending from the posterior border of hard palate In swallowing or speaking, it moves posteriorly against the pharyngeal wall to close the oropharyngeal isthmus Continuous with palatoglossal and palatopharyngeal folds Innervation: lesser palatine nerves and vagus nerves Blood supply: greater and lesser palatine arteries of descending palatine artery (maxillary artery), ascending palatine arteries (facial artery), and palatine branch of ascending pharyngeal artery 7  MUSCLES OF THE SOFT PALATE MUSCLES OF THE TONGUE Tensor veli CN V3 Tenses soft palate EXTRINSIC MUSCLES – alters the position of the tongue palatini Palatoglossus CN X Elevation Levator veli Elevates soft palate Genioglossus Protrusion palatini CN X via CN XII Bulk of tongue Palatoglossus pharyngeal Elevates tongue Hyoglossus Depression plexus Narrows oropharyngeal Styloglossus Retraction isthmus⋆ INTRINSIC MUSCLES Palatopharyngeus Elevates pharynx Superior, inferior, Closes nasopharynx longitudinal, CN XII Alters the shape Musculus uvulae Elevates uvula transverse & of the tongue vertical MAJOR SALIVARY GLANDS TONGUE Attached by muscles to hyoid bone, mandible, styloid process, palate and pharynx Divided by a V-shaped sulcus terminalis into an anterior A. PAROTID GLAND 2/3 and posterior 1/3 Largest, purely serous acini Foramen cecum: located at the apex of sulcus terminalis; Occupies retromandibular space between the ramus indicates site of origin of the thyroglossal duct of mandible in front, and mastoid process and SCM Lingual tonsils: located at the posterior 1/3 of the dorsum behind of tongue Facial nerve (CN VII) crosses the substance of the Innervation: gland, and serves as a landmark in dividing the gland o Hypoglossal nerve: extrinsic and intrinsic muscles of into superficial and deep lobes the tongue, except for palatoglossus (CN X) o Marginal mandibular branch is the branch of o Lingual nerve (CN V): general common sensation of CN VII most at risk for injury during anterior 2/3 of tongue parotidectomy o Chorda typmani (CN VII): taste sensation of anterior Parotid sheath: dense fibrous capsule from investing 2/3 of tongue layer of deep cervical fascia o Glossopharyngeal nerve: general and taste Parotid (Stensen’s) duct: crosses masseter à sensation of posterior 1/3 of tongue buccinator à opens into vestibule of oral cavity o Internal laryngeal branch of CN X: general and taste opposite 2nd upper molar tooth sensation of epiglottic region of tongue and epiglottis Secretomotor innervation: CN IX Blood supply: o Lingual artery, which arises from the external carotid B. SUBMANDIBULAR GLAND artery at the level of the tip of the greater horn of hyoid Produces most of saliva bone in the carotid triangle Mixed gland (predominantly serous) Ensheathed by investing layer of deep cervical fascia Lies in submandibular triangle Superficial portion: superficial to mylohyoid Deep portion: between hyoglossus and styloglossus medially, mylohyoid laterally, and between the lingual nerve above and hypoglossal nerve below Wharton’s duct: empties at the summit of the sublingual papilla at the side of the tongue frenulum Secretomotor innervation: CN VII C. SUBLINGUAL GLAND Smallest, Mixed gland (predominantly mucous) Located in the floor of mouth between mucous membrane above and mylohyoid below Duct of Rivinus (smaller) and Duct of Bartholin (larger): where the gland empties into the floor of the mouth along the sublingual fold LINGUAL PAPILLAE Secretomotor innervation: fibers from submandibular Vallate Form a “V” in front of the sulcus terminalis ganglion either directly or through the lingual nerve Numerous taste buds of CN V3 Fungiform Mushroom-shaped with red heads Scattered on the sides on the apex of the FREY SYNDROME tongue Complicating following a penetrating wound to the Filiform Numerous, slender, conical parotid gland Arranged in rows parallel to sulcus Produces sweat secretion, instead of saliva production terminalis Postganglionic parasympathetic secretomotor fibers Only papillae with no taste buds traveling in the auriculotemporal nerve (CN V branch) Foliate Rudimentary in humans grow out and joint the distal end of the great auricular nerve, which supplies the sweat glands of the overlying facial skin. TONSILS Masses of lymphoid tissue at the posterior wall of pharynx Traps bacteria and viruses, and produces antibodies Waldeyer’s Tonsillar Ring: o ring of lymphoid tissue at the oropharyngeal isthmus o LATERAL: palatine & tubal tonsils o UPPER: pharyngeal tonsil/ adenoids o LOWER: lingual tonsil 8  Pharyngeal At the posterior wall and roof of the (1) nasopharynx Called as adenoid, when enlarged At each side of oropharynx between the palatoglossal and palatopharyngeal folds Highly vascular, supplied by branches of Palatine facial, maxillary, pharyngeal and lingual (2) arteries Innervation: branches of CN IX and the lesser palatine branches of maxillary nerve Tubal aka Eustachian tonsil (2) At the pharyngeal opening of auditory tubes Innervation: Lingual At the posterior portion of the dorsum of the o SVA (smell) sensation: olfactory nerve (1) tongue o GSA sensation: branches of the ophthalmic nerve, maxillary nerve and infraorbital nerve Blood supply (Little’s Area/ Kiesselbachs Plexus⋆): o Anterior and posterior ethmoidal arteries (from ophthalmic artery) o Sphenopalatine artery (from maxillary artery) o Greater palatine branch of descending palatine artery (of maxillary artery) o Superior labial artery and lateral nasal branch of facial artery NOSE Opens on the face through the anterior nasal apertures (nares/ nostrils) and communicates with the nasopharynx PARANASAL SINUSES through the choanae Functions in voice resonance, reduction of weight, Vestibule: a slight dilatation inside the aperture of each produces mucus nostril; lined with skin containing hair, sebaceous glands and sweat glands Warms, cleans, humidifies, filters inhaled air for respiration; helps in smell and test NASAL MEATUS SINUS OPENING INTO IT Superior meatus Posterior ethmoidal sinus Middle meatus Anterior ethmoidal sinus Middle ethmoidal sinus Maxillary sinus Frontal sinus Inferior meatus Nasolacrimal duct Roof Nasal, frontal, ethmoid (cribriform plate) and sphenoid (body) bones Floor Palatine process of maxilla and horizontal plate of palatine bone Nasal septum = perpendicular plate of ethmoid Medial bone, vomer and septal cartilage wall Also formed by processes of palatine, maxillary, frontal, sphenoid and nasal bones Superior and middle conchae of ethmoid bone, and inferior concha Also formed by nasal bone, frontal process and REACHES FIRST nasal surface of maxilla, lacrimal bone, SINUSES LOCATION ADULT SIZE RADIOLOGICAL AFTER BIRTH EVIDENCE perpendicular plate of palatine bone, and Each side of medial pterygoid plate of sphenoid bone maxilla, lateral Lateral to the lateral RELATED STRUCTURES: wall Maxillary wall of nasal 15 years 4-5 months SPHENOETHMOIDAL RECESS cavity and Opening of sphenoid sinus inferior to the SUPERIOR MEATUS orbital floor Opening of posterior ethmoidal air cells Within MIDDLE MEATUS ethmoidal Opening of frontal sinus into the infundibulum Ethmoid labyrinth 12 years 1 year Opening of middle ethmoidal air cells on the between orbit ethmoidal bulla & nasal cavity Openings of anterior ethmoidal air cells and Sphenoid Body of 15 years to 4 years maxillary sinus in the hiatus semilunaris sphenoid adult age INFERIOR MEATUS 📌 Frontal Frontal bone Teens 6 years Opening of nasolacrimal duct SPHENOPALATINE FORAMEN Present at birth: maxillary and ethmoid ( ME!) Opening into pterygopalatine fossa (transmits Largest: Maxillary sphenopalatine artery and nerve) 9  EARS o Round Window (⋆ Fenestra Cochlea or Tympani): accommodates pressure waves transmitted to the perilymph of the scala tymapani A. EXTERNAL EAR Receives sound waves BOUNDARIES 1. Auricle: Roof Tegmen tympani o a cartilage covered by skin that funnel sound Floor Jugular fossa waves into the external auditory meatus (w/ internal jugular vein) o Sensory innervation: auricular branch of CN V, Carotid canal CN VII and greater auricular nerve, Anterior (w/ internal carotid artery) auriculotemporal branch of CN V, and lesser Auditory tube occipital nerves Canal for tensor tympani o Blood supply: superficial temporal and posterior Mastoid air cells & mastoid auricular arteries antrum through the aditus ad o Features: helix, antihelix, concha, tragus, lobule Posterior antrum Pyramidal eminence (from whose 2. External Auditory (Acoustic) Meatus apex emerges the tendon of the o Approximately 2.5 cm long stapedius) (concha à tympanic membrane) Lateral Tympanic membrane o External 1/3: cartilage, internal 2/3: bone Lateral wall of inner ear, o Sensory innervation: Auriculotemporal branch of presenting the promontory formed CN V and auricular branch of CN X, which is Medial by the basal turn of the cochlea, joined by a branch of CN VII and CN IX oval window, round window and o Blood supply: superficial temporal, posterior prominence of the facial canal auricular and maxillary arteries 2. Stapedius Muscle 3. Tympanic Membrane (Eardrum) o Inserts to the neck of the stapes o Thickened fibrocartilaginous ring at the greater o Innervation: CN VII part of its circumference, which is fixed in the o Prevents excessive oscillation of the stapes; tympanic sulcus at the inner end of the meatus protects the inner ear from injury from loud noise o Conducts sound waves to the middle ear o Paralysis results in hyperacusis o Layers: outer cutaneous, intermediate fibrous, inner mucous 3. Tensor Tympani Muscle o Cone of light seen at anterior-inferior quadrant o Inserts to the hand of the malleus o External/lateral concave surface: o Innervation: CN V3 § Covered by skin o In response to loud noises, it draws the eardrum § Innervation: auriculotemporal branch of CN medially and tightens it to increase the tension V, auricular branch of CN X which is joined and reduce the vibration of the eardrums by branches of CN IX and CN VII § Blood supply: deep auricular artery of the 4. Auditory Ossicles maxillary artery o Transmit sonic vibration from the tympanic o Internal/medial surface: membrane to the inner ear; amplify the force § Covered by mucous membrane o Malleus (Hammer) § Serves as attachment for the hand of the § Largest malleus § Attachment for tensor tympani § Innervation: tympanic branch of CN IX o Incus (Anvil) § Blood supply: auricular branch of occipital o Stapes (Stirrup) artery and the anterior tympanic artery § attachment for stapedius at the neck § attached by the annular ligament to the B. MIDDLE EAR margin of the oval window Within the petrous portion of temporal bone Transmits sound waves from air to auditory ossicles, 5. Auditory (Eustachian/ Pharyngotympanic) Tube and then to the inner ear o Connects middle ear to nasopharynx Innervation: tympanic branch of CN IX, which forms o Balances pressure in the middle ear with the tympanic plexus with caroticotympanic nerve from atmospheric pressure the internal carotid plexus of sympathetic fibers o Remains closed except during swallowing or Blood supply: stylomastoid branch of the posterior yawning; opened by contraction of tensor veli auricular artery; anterior tympanic branch of maxillary palatini and salpingopharyngeus artery C. INNER EAR 1. Tympanic Cavity Acoustic apparatus: cochlea (cochlear duct) o Includes the tympanic cavity proper and Vestibular apparatus: vestibule (utricle & saccule) epitympanic recess and the semicircular canals (semicircular ducts) o Anterior communication with eustachian tube Where vibrations are transduced to specific nerve o Posterior communication with mastoid air cells impulses that are transmitted through the acoustic and mastoid antrum through the aditus ad nerve to the CNS antrum o Traversed by chorda tympani and lesser petrosal 1. Bony labyrinth nerve o Vestibule, cochlea, 3 semicircular canals (SSC) o Oval Window (⋆ Fenestra Vestibuli): transmits o Filled with perilymph sonic vibrations of the ossicles into the perilymph o Houses the membranous labyrinth of the scala vestibuli o Vestibule: a cavity communicating with the cochlea anteriorly and the SSC posteriorly 10  o Cochlea: consists of scala vestibuli and scala Roof Platysma and investing layer of the deep tympani cervical fascia § The upper scala vestibuli begins in the Subdivisions Submental Triangle/ Suprahyoid vestibule and received vibration transmitted Triangle to the perilymph at the oval window Digastric Triangle/ Submandibular § The lower scala tympani communicates Triangle with the scala vestibuli through the Carotid Triangle helicotrema at the apex of the cochlea and Muscular Triangle/ Inferior Carotid/ ends at the round window, where the sound Omotracheal Triangle pressure waves are dissipated 2. Membranous labyrinth TRIANGLE CONTENTS o Filled with endolymph ANTERIOR TRIANGLES o Contains sensory organs o Utricle and saccule: dilated membranous sacs Submental Submental lymph nodes in the vestibule and contain the macula, which Submandibular gland detects linear acceleration of the head Submandibular Submandibular lymph nodes § Macula of utricle: horizontal orientation CN XII, Mylohyoid nerve § Macula of saccule: vertical orientation Parts of facial artery and vein o Semicircular ducts: anterior (superior), lateral, Carotid sheath posterior External carotid artery § With dilated ends called ampullae, detects CN XI, XII rotational/angular acceleration Carotid Superior root of ansa cervicalis o Cochlear duct (scala media): Thyroid gland, larynx, pharynx § Located between scala media & tympani Deep cervical lymph nodes § Contains endolymph and the spiral Organ Branches of cervical plexus of Corti, for auditory stimuli Muscular Sternothyroid, sternohyoid § Thyroid and parathyroid glands POSTERIOR TRIANGLES External jugular vein CN XI Occipital Branches of cervical plexus Trunks of brachial plexus Cervicodorsal trunk Cervical lymph node Subclavian artery (3rd part) and vein Subclavian Suprascapular artery Supraclavicular lymph nodes E. NECK HYOID TRIANGLES OF THE NECK HYOID BONE U-shaped bone: a body, a pair of greater horns and a pair BOUNDARIES of lesser horn Superior Lower border of the mandible Horseshoe-shaped bone situated in the anterior midline of Inferior Clavicle the neck that lie at the base of the mandible ⋆ Anterior Anterior midline of the neck At the level of C3 Posterior Trapezius The only bone with no bony articulations ⋆, but serves a movable base for the tongue HYOID MUSCLES Subdivided in to suprahyoid and infrahyoid group of muscles POSTERIOR TRIANGLE BOUNDARIES Anterior Posterior border of SCM Posterior Anterior border of trapezius Inferior Superior border of clavicle Roof Platysma and investing (superficial) layer of the deep cervical fascia` Floor Splenius capitis, levator scapulae, anterior SUPRAHYOID scalene, middle scalene, posterior scalene Mylohyoid Mylohyoid Elevates hyoid muscles nerve of CN V Elevates floor of mouth Subdivisions Occipital Triangle Depresses mandible Subclavian Triangle/ Supraclavicular Digastric – Mylohyoid Elevates hyoid Triangle/ Omoclavicular Triangle Anterior Belly nerve of CN V Elevates floor of mouth Depresses mandible ANTERIOR TRIANGLE Digastric – CN VII Elevates hyoid BOUNDARIES Posterior Elevates floor of mouth Belly Depresses mandible Anterior Anterior midline of the neck Posterior Anterior border of SCM Stylohyoid CN VII Elevates hyoid (Sternocleidomastoid) Geniohyoid C1 via CN XII Elevates hyoid Superior Inferior border of mandible Elevates floor of mouth 11  SUPERFICIAL CERVICAL LYMPH NODES ↓ Deep cervical lymph nodes Lie along the external jugular vein in the posterior triangle and along the anterior jugular vein in the anterior triangle DEEP CERVICAL LYMPH NODES A. SUPERIOR DCLN Receives afferent lymphatics from: back of the head and nek, tongue, palate, nasal cavity, larynx, pharynx, trachea, thyroid gland, esophagus INFRAAHYOID ↓ SUPERFICIAL GROUP Efferent vessels join with the inferior DCLN Omohyoid Ansa cervicalis Depresses and retracts B. INFERIOR DCLN (C1-C3) hyoid and larynx Receives afferent lymphatics from: Sternohyoid Ansa cervicalis Depresses hyoid and anterior jugular, transverse cervical and apical axillary nodes larynx ↓ DEEP GROUP Efferent vessels join with the superior DCLN Sternothyroid Ansa cervicalis Depresses hyoid and ↓ larynx Jugular trunk Thyrohyoid C1 via CN XII Depresses hyoid ↓ Elevates larynx Thoracic duct Junction of the internal (LEFT SIDE) jugular and subclavian veins (RIGHT SIDE) STYLOID PROCESS A slender projection of variable length and extends down Superior DCLN: lie along the internal jugular vein in the and forward from the temporal bone carotid triangle of the neck Serves as origin for the ff: Inferior DCLN: lie along the internal jugular vein near o Stylohyoid, Styloglossus, Stylopharyngeus the subclavian vein o Stylohyoid and stylomandibular ligaments LYMPH NODES LEVEL OF THE NECK Level IA Submental nodes Level IB Submandibular nodes Level IIA Jugulo-digastric nodes Level IIB Submuscular nodes Level III Middle Jugular nodes Level IV Lower Jugular nodes Level VA/B Posterior Triangle nodes Level VI Anterior Compartment nodes Level VII Paratracheal nodes LYMPHATICS CERVICAL PLEXUS Formed by ventral primary rami of C1 to C4 SUPERFICIAL LYMPH NODES OF THE HEAD Branches to the neck: cutaneous and motor Lymph vessels from face, scalp and ear ↓ CUTANEOUS BRANCHES INNERVATION Occipital, retroauricular, parotid, buccal (facial), Lesser Occipital Nerve Lateral part of occipital submandibular, submental and superficial cervical nodes (C2) region and medial surface of ↓ auricle Deep cervical nodes Greater Auricular Nerve Skin behind the auricle and (C2-C3) on the parotid gland DEEP LYMPH NODES OF THE HEAD Transverse Cervical Nerve Skin of the anterior cervical Middle Ear → Retropharyngeal & upper deep (C2-C3) triangle cervical nodes Supraclavicular Nerve Skin over the clavicle and Nasal cavity, Submandibular, retropharyngeal & (C3-C4) shoulder Paranasal → upper deep cervical nodes sinuses MOTOR BRANCHES INNERVATION Tongue → Submental, submandibular & upper Ansa Cervicalis Infrahyoid muscles, except and lower cervical nodes (C1-C3) the thyrohyoid Larynx → Upper and lower deep cervical nodes Phrenic Nerve Motor to the diaphragm Pharynx → Retropharyngeal & upper and lower (C3-C5) Sensation to its central part deep cervical nodes Twigs from the plexus Longus capitis and cervicis, Thyroid Gland → Lower deep cervical, prelaryngeal, SCM, trapezius, levator pretracheal & paratracheal nodes scapulae, scalene muscles Accessory Phrenic Nerve Diaphragm (C5) 12  o Extends from the skill base to the level of 7th cervical vertebra, where it merges with the pretracheal fascia 7. CAROTID SHEATH o Contains the common & internal carotid arteries, internal jugular vein and vagus nerve o Blends with the prevertebral, pretracheal, and investing layers o Attaches to the base of the skill 8. BUCCOPHARYNGEAL FASCIA o Covers the buccinator muscles and pharynx o Blends with the pretracheal fascia o Attached to the pharyngeal tubercle and the pterygomandibular raphe 9. PHARYNGOBASILAR FASCIA o A fibrous coat in the wall of the pharynx o Located between the mucous membrane and the pharyngeal constrictor muscles CERVICAL FASCIA 10. RETROPHARYNGEAL SPACE o A potential space between the prevertebral fascia and Superficial Cervical Fascia buccopharyngeal fascia Deep Cervical Fascia/ Fascia Colli o Extends from the skull base into the posterior o Superficial (Investing) Layer of the Deep Cervical mediastinum Fascia o Retropharyngeal space extends from the skill base to o Pretracheal Layer the superior mediastinum, limited inferiorly by the o Carotid Sheath fusion of alar fascia to the visceral layer o Prevertebral Layer o The alar fascia forms further subdivisions of the Alar Fascia retropharyngeal space. Between the alar fascia and Buccopharyngeal Fascia the prevertebral fascia is the DANGER SPACE, which Pharyngobasilar Fascia extends down from the skull base to the posterior Retropharyngeal Space mediastinum 1. SUPERFICIAL CERVICAL FASCIA o Encloses the platysma 2. SUPERFICIAL/INVESTING LAYER OF THE DEEP CERVICAL FASCIA o Encloses the SCM and trapezius o Attached superiorly along the mandible, mastoid process, external occipital protuberance and superior nuchal line of the occipital bone o Attached inferiorly along the acromion and spine of the scapula, clavicle, and manubrium sterni o Suprasternal Space of Burns § A space formed as superficial layer of the deep cervical fascia divides into anterior and posterior parts attached to the borders of the sternal notch § Contains: sternal head of SCM, loose areolar tissue, jugular venous arch, interclavicular ligament 3. PREVERTEBRAL LAYER OF DEEP CERVICAL FASCIA o Encloses the vertebral column and its associated muscles o Covers the scalene muscles and the deep back muscles; forms the facial floor of the posterior triangle o Extends laterally over the first rib into the axilla to form the axillary sheath o Attached to the external occipital protuberance and the basilar part of the occipital bone o Becomes continuous with the endothoracic fascia and the anterior longitudinal ligament of the bodies of the vertebrae in the thorax 4. PRETRACHEAL LAYER OF THE DEEP CERVICAL FASCIA o Invests the larynx and trachea o Encloses the thyroid and parathyroid glands o Continuous with the buccopharyngeal fascia o Attached superiorly to the thyroid and cricoid cartilage o Attached inferiorly to the pericardium 5. CAROTID SHEATH o Contains the common & internal carotid arteries (medial), internal jugular vein (lateral) and vagus nerve (posterior) o Blends with the prevertebral, pretracheal, and investing layers o Attaches to the base of the skill 6. ALAR FASCIA o Ancillary layer of the deep cervical fascia between the pretracheal and prevertebral fasciae, and forms a subdivision of the retropharyngeal space o Blends with the carotid sheath laterally 13  ROOT OF THE NECK 3. LARYNGOPHARYNX/ HYPOPHARYNX Between the upper border of the epiglottis to the lower border of the cricoid cartilage The piriform recesses are located on each side of the opening of the larynx, in which swallowed foreign bodies may be lodged Opens in the larynx and esophagus Area of the neck immediately above the inlet of the thorax The key muscle is the SCALENUS ANTERIOR, deeply placed and descends vertically from the vertebral column to the 1st rib PHARYNGEAL PLEXUS RELATIONS: Pharyngeal branches of the glossopharyngeal and vagus o ANTERIOR: carotid arteries, vagus nerve, IJV, deep nerves + sympathetic branches from the superior cervical cervical lymph nodes ganglion o POSTERIOR: pleura, origin of the brachial plexus, 2nd Vagal branch innervates all the muscles of the pharynx part of subclavian artery EXCEPT for stylopharyngeus, which is supplied by CN IX o MEDIAL: vertebral vessels, thoracic duct Glossopharyngeal component supplies sensory fibers to o LATERAL: branches of cervical plexus, 3rd part of the pharyngeal mucosa subclavian artery Thoracic outlet: where the thoracic cavity communicates ARTERIES OF THE PHARYNX with the roof of the neck Ascending pharyngeal artery o “Thoracic outlet” – clinical term ⋆ Ascending palatine branch of Facial Artery o “Thoracic inlet” – anatomical term Descending palatine arteries Pharyngeal branches of the maxillary artery ZONES OF PENETRATING NECK TRAUMA Branches of the superior and inferior thyroid arteries Location Structures Involved Cervical pleura, lung PHARYHEAL MUSCLES/ MUSCLES OF DEGLUTITION From the clavicles apex, thyroid and CIRCULAR MUSCLES and manubrium to parathyroid glands, Superior constrictor Constrict upper pharynx ZONE I the inferior border trachea, esophagus, Middle constrictor CN X Constrict lower pharynx of the cricoid common carotid Inferior Constrictor Constrict lower pharynx cartilage arteries, jugular veins, LONGITUDINAL MUSLCES cervical vertebra Stylopharyngeus CN IX Elevates pharynx & Superior poles of thyroid larynx From the cricoid gland, thyroid and Palatopharyngeus Elevates pharynx & CN X cartilage to the cricoid cartilages, larynx, larynx ZONE II level of the angle of carotid arteries, jugular Closes nasopharynx the mandible veins, esophagus, Salphingopharyngeus Elevates pharynx hypopharynx, cervical Opens auditory tube vertebra Above the level of Salivary glands, oral and ZONE III the angle of the nasal cavities, mandible oropharynx, nasopharynx PHARYNX Funnel-shaped fibromuscular tube Upper, wider ending lies under the skull and its lower, narrower ending is at the inferior border of the cricoid cartilage and is continuous with the esophagus at the level of C6 vertebra Openings: 2 auditory tubes, 2 posterior nares, larynx, esophagus Tonsils: pharyngeal, palatine, lingual, tubal SUBDIVISIONS 1. NASOPHARYNX Behind nasal cavity above the soft palate Contains the pharyngeal tonsils Connected with the tympanic cavity through the eustachian tube for air pressure equalization 2. OROPHARYNX Between the soft palate and superior border of the epiglottis Contains the palatine tonsils in the tonsillar fossae and are bounded by the palatoglossal and palatopharyngeal folds 14 PHARYNGEAL (BRANCHIAL APPARATUS) Arytenoid Paired elastic and hyaline cartilage; Cartilage pyramid-shape ARCH POUCH GROOVE MEMBRANE Its bases articulate with and rotate on the