Ear and Nose Anatomy Flashcards
what is the arterial supply to the cranial cavity?
internal carotid and vertebral
arterial supply to the face?
ECA and ICA
arterial supply to the neck
ICA and subclavian
branches of the external carotid
Superior thyroid ascending pharyngeal artery lingual artery facial artery occipital artery posterior auricular artery maxillary artery superficial temporal artery
describe head and neck venous drainage
cranial cavity drains to the dural venous sinuses
all ultimately drain to IJV
what is the ganglion for oculomotor III
ciliary
what is the ganglion for facial VII
pterygopalatine
submandibular
geniculate
what is the ganglion for the glossopharyngeal IX
otic
what nerves supply somatic sensory to the face
trigeminal V1,2,3
IX
X
special sensory to head?
smell
vision
taste
hearing and balance
ganglion for CN VIII
spiral and vestibular
components of the lateral wall of nasal septum
superior, middle concha inferior concha palatine bone sphenopalatine foramen lateral cartilage maxilla
components of medial wall of nasal septum
perpendicular plate of ethmoid
septal cartilage
vomer
5 arteries contributing to littles area?
anterior ethmoidal artery posterior ethmoidal artery sphenopalatine artery greater palatine artery septal branch of superior labial artery
branches of ophthalmic artery contributing to nasal cavity, what do they pass through and where does it come from
anterior and posterior bilateral arteries
pass through anterior and posterior ethmoidal foramen
branch of ICA
branches of maxillary artery contributing to nasal cavity, what do they pass through and where does it come from
sphenopalatine, through sphenopalatine foramen
greater palatine artery - through incisive foramen superiorly
from ECA
branches of facial artery contributing to nasal cavity
septal branch of superior labial artery
lateral nasal artery
epithelia of nasal vestibule
stratified squamous
ketatinised and then becomes non-keratinised on entering cavity
epithelia of the nasal cavity
respiratory on middle and inferior concha
olfactory on superior
describe the process of olfaction
air enters nasal cavity and is made turbulent by nasal conchae
these reach receptor cells (olfactory cells) and pass along cribiform plate to synapse with olfactory bulb, pass along tract and into temporal lobe
describe somatic sensation to anterosuperior nasal cavity
CN V1 by anterior ethmoidal nerve
sensation is carried through sup orbital fissure to trigeminal ganglion to pons
describe somatic sensation to posteroinferior nasal cavity
CN V2 by nasopalatine nerve
axons pass from foramen rotundum, to trigeminal ganglion and pons
bones of the skull?
frontal zygomatic maxilla mandible nasal palatine sphenoid ethmoid vomer inferior concha temporal occipital parietal lacrimal
foramina of anterior cranial fossa?
cribiform plate
anteiror and posterior ethmoidal foramen
foramina of middle cranial fossa?
optic canal foramen ovale foramen rotundum superior orbital fissure foramen spinosum internal acoustic meatus
foramina of posterior cranial fossa
foramen magnum
hypoglossal canal
carotid canal
jugular foramen
what bones do the nasal conchae belong to and their meatuses?
sup and middle are ethmoid inf is its own bone post to sup concha is sphenoethmoidal recess sup-mid concha is superior meatus mid-inf is middle meatus inferior to inf concha is inf meatus
name the bilateral nasal sinuses
ethmoidal air cells
frontal sinus
maxillary sinus
sphenoid sinus
where does the sphenoid sinus drain
sphenoethmoidal recess
what does the superior meatus drain
posterior ethmoidal air cells
what does the middle meatus drain
semilunar hiatus - frontal sinus, maxillary sinus, ant ethmoidal air cells
ethmoidal bulla - middle ethmoidal air cells
what does the inferior meatus drain
nasolacrimal duct
border and contents of nasopharynx
posterior nasal cavity to soft palate choanae torus tuberalis pharyngeal recess salpingopharyngeal fold opening for the eustachian tube
border and contents of oropharynx
soft palate to superior epiglottis palatine tonsil palatoglossal arch palatopharyngeal arch lingual tonsil
what makes up the supraglottis
ventricle and vestibule
components of laryngeal skeleton
hyoid epiglottis thyroid cartilage cricoarytenoid joint cricoid cartilage 1st tracheal cartilage arytenoid cartilage ligaments
ligaments of larynx
conus elasticus
quadrangular membrane
vestibular ligament
vocal ligament
components of the thyroid cartilage
superior horn
inferior horn - for cricothyroid joint
laryngeal prominence
what is the oral vestibule
internal lips to external teeth
what is the oral cavity proper
internal surface of teeth to oropharynx
features of the oral cavity proper
upper and lower dental arch gingivae palatine tonsils uvula arches of soft palate oropharynx deep lingual vein lingual frenulum with caruncle sublingual fold
osteological features of oral cavity
incisive foramen palatine process median palatine suture palatine bones and maxilla lesser and greater palatine foramen lateral and medial pterygoid plate of sphenoid bone
during laryngoscopy, where should the macintosh blade be placed and describe this site
vallecula
mucosal lined space between base of tongue and anterior epiglottis
what are the modalities of the pterygopalatine ganglion?
parasympathetic
special sensory
somatic motor
general sensation
describe facial nerve innervation to the pterygopalatine ganglion
facial nerve synapses at the geniculate ganglion and passes via the greater petrosal nerve in combination with deep petrosal nerve to form vidian
this combines to synapse at the pterygopalatine junction
where is the pterygopalatine junction located and by what nerve is it suspended
pterygopalatine fossa, located between sphenoid bone and maxilla
CN V2
describe parasympathetic outflow from pterygopalatine ganglion to innervating structures
passes out to innervate pharynx, palate and nasal cavityby greater petrosal nerve
branch crosses V2 to join CN V1, as zygomatic nerve and supplies lacrimal gland
describe somatic sensory outflow from pterygopalatine ganglion
pass through but do not synapse
pass through by CN V2
to palate, nasal cavity and pharynx
describe sympathetic outflow from pterygopalatine ganglion
doesnt synapse
passes through by deep petrosal nerve and outflow to palate, pharynx and nasal cavity
surface anatomy of the external ear
tragus anti tragus helix anti helix ear lobe external acoustic meatus
what supplies posterior superior pinna
lesser occipital nerve of C2,3
what supplies posterior inferior pinna
greater auricular nerve of C2,3
nerve supply to auditory canal?
auriculotemporal - V3 to ant sup canal
vagus supplies inf post
facial in minute somatic of concha
what drains lymoh of external ear
pre/post auricular lymph nodes
besides the auditory canal, what else does the auriculotemporal nerve supply
temporalis muscle
describe bone conduction in the middle ear
handle of malleus conducts from tympanic membrane to head and transfers on to incus and then to stapes
amplify sound and controlled by muscles and synovial joints
what supports the head of malleus
ligaments suspended from tegmen tympani
attachments and innervation of tensor tympani
cartilagenous part of eustachian tube to handle of malleus
CN V3
attachments and innervation of stapedius
pyramidal eminence to neck of stapes
facial nerve
functions of stapedius and tensor tympani
dampen sound by reducing vibration of tympanic memebrane (TT) or stapes on oval window (S)
true/false - tympanic air pressure is greater than atmospheric and is regulated by nasal muscles pulling the eustachian tube open
false- tympanic pressure should be equal as imbalance causes reduced ossicle vibration
the eustachian tube is opened by palate muscles
describe the general nervous innervation to the tympanic cavity
by tympanic plexus, CN IX
supplies pharynx first then forms tympanic plexus over promontory
comes with lesser petrosal to form autonomics to parotid
modalities of the tympanic plexus?
parasympathetic and general sensory
what is the mastoid antrum and why is it clinically relevant
opening between mastoid air cells and tympanic cavity
opening is posterior wall of epitympanic recess and is the aditus
can provide surgical access, infection or inflammation can lead to osteomyelitis
sensory nerve supply to the eustachian tube?
CN IX
describe how the eustachian tibe can contribute to middle ear infection
bacteria or viruses can be spread from the pharynx/tonsils to middle ear, esp children as they have a shorter tube
attachments of the eustachian tube
anterior wall of tympanic cavity to nasopharynx
location of inner ear
otic capsule, temporal bone
what is the bony labyrinth filled with
perilymph
what is the membranous labyrinth filled with
endolymph
what is the modiolus
bony ridge permitting perilymph vibration to nervous AP transmission
describe hearing within the inner ear
sound waves make TM vibrate
conducted across ossicles to footplate of stapes in the oval window
pressure vibration within perilymph
hair cells in cochlea are moved and AP is stimulated along cochlear nerve
dampened at round windown
what is conductive hearing loss
hearing loss due to failed conduction of external/middle ear
what is sensorineural hearing loss
hearing loss due to failed nervous transmission or inner ear
describe the semicircular ducts
3 semicircular canals at right angles
anterior- sagittal
posterior - coronal
lateral - axial
describe balance with respect to the inner ear
ampullae of canals have crests with hair cell clusters
head movement causes movement of hair cells due to endolymph
generates AP carried to vestibular ganglion and then to vestibular nerve
what is carried through the IAM
CN VII and VIII
laryrinthine artery and veins
modalities of the facial nerve
special sensory
somatic sensory
somatic motor
parasympathetic secretomotor
describe the course of the facial nerve
leaves brainstem at cerebellopalatine junction to enter IAM
travels through temporal bone and exits stylomastoid foramen
gives off the geniculate ganglion and courses to the parotid
gives off chorda tympani in canal
what does the facial nerve act on?
lacrimal glands
ant 2/3 tongue
muscles of facial expression
mouth and nasal cavity
temporal branches of the facial nerve?
nerve to stapedius
greater petrosal
chorda tympani
descrive the fucntion and course of chorda tympani
taste to 2/3 tongue and parasympathetic fibres to submandibular and sublingual gland
courses between incus and malleus and leaves tympanic cavity at petrotympanic fissure to join CN V3
taste and general sensation to ant 2/3 tongue
Sensation CN V3
taste by VII
taste and general sensation to post 1/3 tongue
IX
features of the temporal bone
petrous squamous styloid process external/internal AM mastoid process stylomastoid foramen glenoid fossa external carotid canal zygomatic process
what is EAM made up of
2/3 internal bone and outer 1/3 cartilage
features of tympanic membrane via otoscope
para flaccida
umbo
pars tenda
cone of light
true/false- the ear ossciles are fully developed at birth
true
true/false - ear ossicles are joined by fibrous joints
false - synovial
what is tympanic cavity proper and epitympanic recess
make up total tympanic cavity
tympanic caivty proper is floor to top of tymopanic membrane
epitympanic recess is superior to tympanic membrane
features of posterior wall of tympanic cavity
mastoid aditus
features of roof of tympanic cavity
tegmen tympani is thin bone to seperate from middle cranial fossa
features of floor of tympanic cavity
closely related to IJV
features of medial wall of tympanic cavity
oval window
round window
promontary
facial canal
features of anterior wall of tympanic cavity
carotid canal relation
chorda tympani
eustachian tube
describe structure of eutachian tuibe and function
post 1/3 bone and rest cartiolage
cartilage typically collapsed and pulled by palate muscles
equalise air pressure
torus tuberalis is feature caused by cartilagenous opening in nasopharynx
what is the vestibule
oval shaped chamber with utricle and saccule and oval window
where are cochlear hair cells located
organ of corti
cell bodies collect AP and convey to spiral ganglion, then onto cochlear nerve
