ear quick study Flashcards
blood supply to auricle
superficial temporal, posterior auricular, occipital
nerve supply to auricle 5
great auricular n, auriculo-temporal, lesser occipital, auricular branch of vagus, facial (motor to auricular mucles)
external acoustic meatus lat 1/3 is what and medial 2/3 is what
lat 1/2 is cartilage
med 2/3 is bony
blood supply to external acoustic meatus
posterior auricular (branch of eca), deep auricular (branch of max), auricular branch of superficial temp a
nerve to external acoustic meatus 2
auriculotemporal nerve of V3, and auricular branch of vagus
central depression of tympanic membrane called
umbo
cone of light radiates
anteroinferiorly
where find cone of light for diff ears
right ear: 5 o clock
left ear: 7
what find in anterior superior of tymp membrane
anterior malleolar fold and parts of pars flaccida
what find in posterior superior of tymp memb
posterior malleolar fold and parts of pars flaccida
what find anterior inferior tymp membe
cone of light
what find post inf tymp memb
safest site for paracentesis: drain
myringotomy: put tube in ear
blood to tymp memb
deep auricular (branch of max): external surface internal: stylomastoid branch of post aur a and tympanic branch of max
nerve to tymp mem
externally: auriculotemporal nerve and auricular branch of vagus
internally: glossopharyngeal n
the middle ear/tymp cavity communicates with the nasopharynx through the
auditory tube
the middle ear/tmp cav communicates with mastoid air cells and mastoid antrum though the
aditus
roof of middle ear
tegmen tympani
floor of middle ear
roof of jugular fossa
anterior wall middle ear
incomplete wall, 2 openings: auditory tube and tensor tympani muscle
posterior wall middle ear
mastoid wall that has aditus,
opening of facial canal, and pyramid process in it
medial wall of middle ear is also the
lateral wall of the inner ear
whats in medial wall of mid ear
promontory
oval window
round window
oval window aka
fenestra vestibuli
round window aka
fenestra cochleae
lateral wall mid ear
tympanic membrane
what is the function of the pyramid process
attachment for stapedius muscle
facial nerve enters petreous portion of temp bone through the () and exits facial canal through the ()
internal acoustic meatus
stylomastoid foramen
if you have a lesion of facial nerve b/f it enters auditory meatus s&s
intracranial
paralysis of muscles of facial expression
hyperacusis (cause of paralysis of stapedius muscle)
loss of taste of anterior 2/3 of tongue: hypoageusia
if lesion of facial nerve after stylomatoid foramen see what
extracranial
paralysis of muscles of facial expression
incus-mallear jt is a () jt
saddle
incus stapes jt is a () jt
ball and socket jt
nerve to tensory tympani muscle
nerve to medial pterygoid
action of tensor tympani
draws tympanic membrane medially increasing its tension thus lessening sound transmission
stapedius muscle nerve
facial nerve
action of stapedius
damps down vibratiosn by pulling the head of stapes posteriorly (protective mechanism)
how long is auditory tube/pharygotympanic/eustachian
3.5-4cm long
function of auditory tube
equalize pressure on both sides
what do if in plane and try to equalize pressure
as go up atmosphere pressure goes down so yawn or chew gum cause our pressure in ear is higher
when go scuba do what to eqaulise pressure
blow nose
herpes zoster auticus affects what
opthlamic divison of trigeminal or auricuotemporal so get lesions on face or ear
where is inner ear
petrous portionof temporal bone
what is suspended in the bony labrinth
membranous labryinth
what is the membranouse labyrinth fileld with
endolymph
what separates the membranous from the bony labyrinth
perilymph
what is bony labyrinth made of
cochlea, vestibule semicircular canals
what is the membranous labyrinth made of
utricle, saccule, semicircular ducts (in canals) and cochlear duct (in cochlea)
what is in the vestibule
utricle and saccule
what contains the sensory e.t cells for hearing
organ of corti/spiral organ
how many turns does cochlea make
2 1/2
the bony core of cochlea
modiolus
modiolus contains
spiral gangli
the thread of bone around modiolus
osseous spiral lamina
what divides the cochlea into 3 division
basilar and vestibular membranes
what are the 3 divisions of the cochlea
upper: scala vestibule
lower: sacala tympani
middle: coclear duct
what are both the scala vestibule and tympani filled wtih
perilymph
the scala vest and tymp connect at the apex through the ()
helicotrema
the scala vest ends at the () and the scala tymp ends at ()
oval window (closed by stapes base)
tymp: round window closed by 2nd tymp membrane
cochlear duct is filled wtih
endolymph
what is ontop of basilar membrane
organ of corti
what is on top of organ of corti
tectorial membrane
what is imbedded in tectorial emmbrane
cilia (hair)
what forms cochlear nere
axons of the bipolar nerve cells from organ of corti
the vestibule is contiunsous anteriorly by the () and posteriorly by the () and posterior cranial fossa through the ()
cochlea
post: semicircular canals
fossa : aquadeuct of vestibule
spot of modified sensory e.t. in utricle called
macula utriculi
spot of modified sensory e.t in saccule
macula sacculi
otoliths
calcium crystals for when go up and down bend cilia to get action potential
function of macula sacculi and utriculi
and innervation of htem
detect acceleration and deceleration, static equilibrium and head in space
vestibular division of cranial 8 vestibulocochlear
sensory organ found in ampulla of circular ducts
crista ampullaris (innervated nerve 8)
function of cristae
kinetic equilibrium, and rotational acceleratioand nd deceleration
what passes through internal acoustic meatus
facial, vestibulocochlear
internal acoustic a. (branch of basilar)
where is primary auditory cortext
superior temporal gyrus
conductive deafness
problem from outer ear to ossicles (like artirist of bones or blockage from earwax)
presbycusis
loss of hearing secondary to old age
sensory neural deafness
damage of spiral oran
