Anatomy Tables - Ear & Nasal Cavity


Bone Structure Description
temporal petrous part (N9, TG7-07) contains tympanic cavity & bony labyrinth (Greek, petra = rock)
internal acoustic meatus (N8,N10, TG7-04, TG7-07) on posterior surface of petrous part; transmits facial nerve, vestibulocochlear nerve, & labyrinthine artery (Latin, meatus = a passage)
facial canal (N94, TG7-68) through petrous part; transmits facial nerve to stylomastoid foramen
carotid canal (N8, TG7-06) through petrous part; transmits internal carotid artery & internal carotid plexus of sympathetic nerves
mastoid process (N94, TG7-06, TG7-68) projects inferiorly from junction of petrous & squamous parts; contains mastoid air cells that open into tympanic cavity through mastoid antrum
tegmen tympani (N92, TG7-66) on anterior surface of petrous part superiorly; thin bony roof of tympanic cavity (Latin, tegman = a cover or roof; Greek, tympanum = a kettle drum)
jugular fossa (N8, TG7-06) on posterior surface of petrous part; forms anterior margin of jugular foramen
tympanic part (N8, TG7-67A, TG7-67B) consists primarily of external acoustic meatus & tympanic ring (Greek, tympanum = a kettle drum)
external acoustic meatus (N8,N10, TG7-04, TG7-07) opening which allows sound to reach tympanic membrane (Latin, meatus = a passage)
tympanic ring (TG7-04) attachment of tympanic membrane
  semicanal for tensor tympani m. (TG7-68A) consists of the superior surface of the cartilaginous part of the pharyngotympanic tube, the greater wing of the sphenoid, and the petrous part of the temporal bone
incus (N92,N93,N94, TG7-65, TG7-68, TG7-69A, TG7-69C) articulates with head of malleus and head of stapes (Latin, incus = anvil)
stapes (N92,N93,N94, TG7-65, TG7-68, TG7-69A, TG7-69D) articulates with long process of incus and base fills vestibular window (Latin, stapes = step or stirrup)
malleus (N92,N93,N94, TG7-65, TG7-68, TG7-69A, TG7-69B) manubrium is attached to inner aspect of tympanic membrane; head articulates with incus (Latin, malleus = hammer)
middle cranial fossa hiatus for greater petrosal nerve (N10, TG7-07) also houses petrosal branch of middle meningeal artery
pterygopalatine fossa (N4, TG7-32) pyramidal space inferior to apex of orbit lies between the pterygoid process of the sphenoid bone posteriorly and the posterior aspect of the maxilla anteriorly (Greek, pterygoid = wing-shaped)
sphenopalatine foramen (N4, TG7-32) communicates with the pterygopalatine fossa medially through the nasal cavity
vomer (N2,N6, TG7-03, TG7-41) thin, flat bone that forms the posteroinferior part of the nasal septum (Latin, vomer = a ploughshare, the latin word is said to have been derived from vomere, to vomit, because the plough "throws up" the earth)
maxilla (N2, TG7-03) upper jaw consitute the supporting bone for the maxillary teeth
sinus (N48,N49, TG7-44A, TG7-44BC) the largest of the paranasal sinuses; occupy the bodies of the maxillae
ethmoid (N6, TG7-08 air cells N48,N49, TG7-44A, TG7-44BC) pneumatized spaces (3-18 in number) within the ethmoid bone; located between the orbits; three groups may be identified: anterior (drain into the hiatus semilunaris in the middle nasal meatus), middle (drain onto the apex of the bulla ethmoidalis in the middle nasal meatus), posterior (drain into the superior nasal meatus) (Greek, ethmoid = resembles a sieve)
perpendicular plate (N6, TG7-41) superior part of the nasal septum that descends from the cribiform plate; superior to the cribiform plate it is the crista galli
cribriform plate (N6, TG7-41) perforated portion of ethmoid bone on either side of the crista galli; perforated for passage of the olfactory nerves
superior nasal concha (N6,N37, N38, TG7-08, TG7-42) medial projection of the ethmoid bone from the superolateral wall of the nasal cavity; forms the superior nasal meatus below it and the sphenoethmoidal recess above it
middle nasal concha (N6,N37, N38, TG7-08, TG7-42) portion of the ethmoid bone that projects inferomedially from the lateral wall of the nasal cavity; forms the superior nasal meatus above it and the middle nasal meatus (which overlies the bulla ethmoidalis and hiatus semilunaris) below it
bulla ethmoidalis (N37,N38, TG7-42, TG7-43) rounded elevation on the lateral wall of the nasal cavity; located under cover of the middle nasal concha; middle ethmoidal air cells drain at its apex
nasal septum (N2, N6, N39, TG7-03, TG7-41A, TG7-41B) divides the chamber of the nose into two nasal cavities, with three major components: perpendicular plate of the ethmoid, vomer, and septal cartilage
nasal conchae (N6,N37, N38, TG7-08, TG7-42) three curved bony plates on the lateral side of each nasal cavity; the superior and middle concha are part of the ethmoid bone, the inferior concha is a separate bone
sphenoid body (N6, TG7-07, TG7-08) central part, containing sinuses (Greek, sphenoid = wedge-shaped)
medial pterygoid plate (N6,N8, TG7-06, TG7-08) projects posteriorly from pterygoid process; attachment of superior pharyngeal constrictor & pharyngobasilar fascia (Greek, pterygoid = wing-shaped)
pterygoid hamulus (N6,N8, TG7-06, TG7-08) hook-like projection from the inferior end of the medial pterygoid plate; it acts as a pulley for the tendon of the tensor veli palatini m. (Greek, pterygoid = wing-shaped; Latin, hamus = hook)

Muscles of Ear

Muscle Origin Insertion Action Innervation Notes Image
stapedius (N93,N94, TG7-66, TG7-68) walls of pyramidal eminence neck of stapes dampens vibration of stapes facial nerve (VII) entirely enclosed in bone, except for its tendon
tensor tympani (N93,N94, TG7-66, TG7-68) cartilagenous auditory tube & greater wing of sphenoid adjacent to it manubrium of malleus dampens vibrations of the tympanic membrane medial pterygoid branch of mandibular division of the trigeminal nerve (V) V3 innervates both tensor muscles (tympani and veli palatini)
levator veli palatini (N64,N65,N68, TG7-20, TG7-24) apex of the petrous part of the temporal bone and the medial surface of the auditory tube cartilage muscles and fascia of the soft palate; palatine aponeurosis elevates the soft palate vagus nerve (X) via the pharyngeal plexus a derivative of the fourth pharyngeal arch (Latin, levator = to lift)
tensor veli palatini (N64,N65,N68, TG7-20, TG7-24) scaphoid fossa, lateral wall of the auditory tube cartilage palatine aponeurosis opens the auditory tube; tenses the soft palate mandibular division of the trigeminal nerve (V) remember: V3 innervates both tensor muscles (tympani and veli palatini); ALL other palatal muscles are innervated by vagus


Nerve Source Branches Motor Sensory Notes
facial (N92, N94, N97,N104,N123, TG7-47, TG7-65, TG7-68, TG7-87) pons & medulla: nucleus solitarius of medulla via nervus intermedius (SVA sensory root) from geniculate ganglion; superior salivatory nucleus (GVE preganglionic parasympathetic) of pons via nervus intermedius, facial motor nucleus of pons via motor root greater petrosal (preganglionic parasympathetic to pterygopalatine ganglion, postganglionic parasympathetic travels with brs. of maxillary div. of V), chorda tympani (SVA taste from anterior 2/3rds of tongue; preganglionic parasympathetic to submandibular ganglion, postganglionic parasympathetic to submandibular & sublingual glands), n. to stapedius, posterior auricular, intraparotid plexus with temporal, zygomatic, buccal, marginal mandibular & cervical brs. stapedius, stylohyoid, posterior belly of digastric, muscles of facial expression; secretomotor to lacrimal, submandibular, sublingual, and mucous glands of nasal & oral cavities taste (SVA) from anterior 2/3rds of tongue; part of skin of external auditory meatus also known as: CN VII, 7th cranial nerve; passes into internal acoustic meatus, goes through facial canal, exits at stylomastoid foramen
ganglion, geniculate (N92, N94, N97, N123, TG7-67B, TG7-68B) chorda tympani, from facial n. (VII) nucleus solitarius of medulla via nervus intermedius (SVA sensory root of facial n.) taste (SVA) from ant. 2/3rds of tongue a sensory ganglion equivalent in structure and function to a dorsal root ganglion; some taste from palate travels through greater petrosal n. to geniculate ganglion; located in facial canal of petrous temporal bone (Latin, geniculate = to bend)
petrosal, greater (N104,N123, TG7-67B, TG7-68B) facial (VII) joins deep petrosal n. to form n. of pterygoid canal secretomotor (preganglionic parasympathetic) to lacrimal gland & mucous glands of lower nasal cavity, maxillary sinus, palate contains: preganglionic parasympathetic axons bound for the pterygopalatine ganglion where they will synapse; passes through hiatus of canal of greater petrosal n. in petrous part of temporal bone
chorda tympani (N94, N123, TG7-67B, TG7-68A) facial (VII) secretomotor to submandibular & sublingual glands (preganglionic parasympathetic to submandibular ganglion) taste to anterior 2/3rds of tongue joins lingual nerve in infratemporal fossa and continues with it to the tongue (Latin, chorda = a cord; Greek, tympanum = a kettle drum)
vestibulocochlear (N92, N97, N104,N124, TG7-65, TG7-67B, TG7-89C) pons & medulla: vestibular nuclei from vestibular ganglion of semicircular ducts; cochlear nuclei in inferior cerebellar peduncle from spiral ganglion of cochlea divides within the temporal bone into vestibular and cochlear parts vestibular: balance/proprioception (SSA); cochlear: hearing (SSA) also known as: CN VIII, 8th cranial nerve; auditory nerve; passes into internal auditory meatus
cochlear (N92, N97, TG7-89C) vestibulocochlear n., cochlear nuclei in inferior cerebellar peduncle from spiral ganglion of cochlea hearing (SSA) passes into internal acoustic meatus
vestibular (N92, TG7-89C) pons & medulla: vestibular nuclei from vestibular ganglion of semicircular ducts balance/proprioception (SSA) part of vestibulocochlear n., CN VIII; passes into internal auditory meatus
glossopharyngeal (N104, TG7-90C) medulla: spinal trigeminal nucleus from superior ganglion (GVA); nucleus solitarius from inferior ganglion (SVA); nucleus ambiguus (GVA); inferior salivatory nucleus (GVE preganglionic parasympathetic) tympanic nerve to tympanic plexus & lesser petrosal n., carotid sinus n., stylopharyngeus brs., pharyngeal brs. GSE: stylopharyngeus; GVE: secretomotor to parotid gland (preganglionic parasympathetic via tympanic n. to lesser petrosal n. to otic ganglion, postganglionic parasympathetic via auriculotemporal n.) GVA: carotid body & sinus, pharynx, middle ear; GSA: skin of external ear; SVA: taste from posterior 1/3rd of tongue also known as: CN IX, 9th cranial nerve; passes through jugular foramen; may penetrate the stylopharyngeus m.
tympanic (TG7-90C) glossopharyngeal tympanic plexus, which gives rise to lesser petrosal n. secretomotor (pregang. parasymp., synapsing in otic gang.) to parotid gland mucous lining of middle ear cavity passes from inferior ganglion of CN IX through tympanic canaliculus to middle ear (Greek, tympanum = a kettle drum)
ganglion, spiral fibers of cochlear hair cells cochlear n. of vestibulocochlear n. to cochlear nuclei in inferior cerebellar peduncle hearing (SSA) sensory ganglion of cochlear part of CN VIII
olfactory nn. (N42,N43, TG7-41 TG7-77AB TG7-77C) the filaments of the bipolar olfactory epithelial cells constitute the olfactory nerves second order olfactory nerve cell bodies located in the olfactory bulb none smell (SVA) also known as CN I, 1st cranial n.; multiple olfactory filaments pass through the cribriform plate to enter the anterior cranial fossa and synapse in the olfactory bulb; the olfactory tract carries the signal from the bulb to olfactory cortex of the forebrain


Organ Location/Description Notes
torus tubarius (TG7-23) mucosal fold covering the anteromedial end of the auditory tube cartilage torus tubarius projects toward the midline from the lateral wall of the nasopharynx (Latin, torus = knot)
arcuate eminence (anterior semicircular canal) (TG7-67) communicate with the vestibule of the bony labyrinth the canals lie posterosuperior to the vestibule into which they open and at right angles to each other (Latin, arucuate = bowed)
auditory (pharyngotympanic) tube (TG7-65, TG7-67) joins the middle ear to the nasopharynx  
epitympanic recess (TG7-68) space superior to the tympanic membrane in the middle ear  
oval window (TG7-70) an oval opening on the medial wall of the tympanic cavity leading to the vestibule of the internal ear (bony labyrinth)  
promontory of the cochlea (TG7-70) bulging of the medial wall of the tympanic cavity produced by the large basal turn of the cochlea  
round window (TG7-70) an opening in the medial wall of the middle ear leading into the cochlea  
outer ear (N92, TG7-65) comprises the auricle, which collects sound, and the external acoustic meatus  
middle ear (N92, TG7-65) located in the temporal bone, it consists of the tympanic cavity and the epitympanic recess  
inner ear (N92, TG7-65) contains the vestibulocochlear organ and the sacs and ducts of the membranous labyrinth  
choanae (N37, N66, TG7-22, TG7-43) posterior opening of the nasal cavities into the nasopharynx (Latin/Greek, choanae = a funnel-shaped hollow in the brain)
soft palate (TG7-24, TG7-43) the movable posterior third of the palate, which is suspended from the posterior border of the hard palate
uvula (TG7-41) conical process that is the posteroinferior extension of the soft palate (Latin, uva/uvula = a grape)


Structure Location Afferents from Efferents to Regions drained Notes
tonsil, pharyngeal (TG7-43) roof and posterior wall of the nasopharynx lymphatic vessels of the wall of the pharynx superior deep cervical nodes "guards" the entrance to the nasopharynx part of the tonsillar ring (of Waldeyer); known as adenoids when inflamed
tonsil, palatine (TG7-38, TG7-39) lateral wall of the oropharynx between the palatoglossal and palatopharyngeal arches lymphatic vessels of the posterior tongue and palatoglossal/palatopharyngeal arch region superior deep cervical nodes, especially the jugulodigastric node "guards" the entrance of the oropharynx part of the tonsillar ring (of Waldeyer); often referred to as "the" tonsils
tonsil, lingual (TG7-39) superior surface of root of tongue lymphatic vessels of the root of tongue and valleculae epiglottica superior deep cervical nodes "guards" entrance of oropharynx part of tonsillar ring (of Waldeyer)

Clinical Terms

Term Definition
otitis media infection or inflammation of the middle ear space and eardrum
myringotomy removal of fluid from the middle ear space by creating an incision in the eardrum. In chronic cases of otitis media, a tube may be left in place to drain the fluid (tympanostomy tube).
otitis externa infection or inflammation of the external ear canal.
mastoiditis inflammation of any part of the mastoid process and the cells.
otosclerosis A pathological condition of the bony labyrinth of the ear, in which there is formation of spongy bone (otospongiosis), especially in front of and posterior to the footplate of the stapes, it may cause bony ankylosis of the stapes, resulting in conductive hearing loss. Cochlear otosclerosis may also develop, resulting in sensorineural hearing loss.
epistaxis nosebleed, hemorrhage from the nose. Usually from superficial vessels in the anterior part of the nasal septum (cartilaginous portion). Bleeding from more posterior vessels is more serious and can be life-threatening requiring prompt care and deep packing.
Kiesselbach's area an area on the anterior portion of the nasal septum where nosebleeds often occur
sinusitis inflammation of a sinus. The condition may be purulent or nonpurulent, acute or chronic. Depending on the site of involvement it is known as ethmoid, frontal, maxillary or sphenoid sinusitis.
deviated septum a common condition in which the nasal septum bows to one or the other side of the nasal cavity rather than being in the midline
cleft palate a congenital fissure in the roof of the mouth forming a communication between the nasal passages and the oral cavity. More common in males. Due to the failure of the maxillary prominence to fuse with the medial nasal prominence (tongue fails to move out of the groove between these two plates). Repair is usually done in the second year of life.
tonsillitis inflammation of the palatine tonsil
tonsillectomy surgical removal of the palatine tonsils. Lingual tonsils are also taken. Indications include airway obstruction or recurrent tonsillitis. Complete recovery is in two weeks. Adults have a significantly longer period of recovery and a much higher complication rate than children.
adenoidectomy surgical removal of adenoids or inflamed pharyngeal tonsils. Indications include airway obstruction, nasal obstruction, sleep apnea and chronic ear infections

The material presented in these tables is contained in the book:
MedCharts Anatomy by Thomas R. Gest & Jaye Schlesinger
Published by ILOC, Inc., New York
Copyright © 1995, unauthorized use prohibited.
The excellent editorial assistance of
Dr. Pat Tank, UAMS
is gratefully acknowledged.