Flashcards in ear anatomy Deck (40):
what is the pterion?
thinnest part of skull, H shaped suture between frontal bone, temporoal bone and sphenoid
2 parts to temporal bone?
petrous and squamous
auricle to tympanic mambrane
tympanic membrane to oval window
oval window to internal acoustic meatus
amplifies and conducts sound
where are the ossicles
where is the eustachian tube
what type of cartilage in external ear?
what comes out of ceruminous glands?
what is the auricle?
the part of the ear wee see outside
what nerve gives sensory supple to the helix and lope and most of posterior auricle?
C2, C3 spinal nerves
what nerve supples the rest of the outer auricle?
what 2 nerves supply ther external canal?
CN X (vagus)
what nerve supplied the collecting bit of auricle before the sound enterss the canal?
vagus and also facial
lateral surface of superior half of auricle drain to what lymph nodes?
cranial surface of superior half drain to what nodes?
mastoid (and deep cervical)
rest of auricle and lobe drain to which nodes?
superficial cervical nodes
all lymph from auricle eventually drains to?
deep cervial nodes, thoracic duct and venous angle
what is an otoscopic examination?
looking at external acoustic meatus and tympanic membrane
children pull back and down
adults-pull back and up
most depressed part of tympanic membrane?
general sensory supply to external ear drum?
CN V3 (mostly)
general sensory supply to external ear drunm?
CN IX glossophyarngeal
general sensory supply to middle ear cavity, eustachian tube, nasopharynx, orophyarnx, tonsils
CN IX glossopharyngeal
connects middle ear to nasopharynx
name the 3 ossicles
what created the umbo?
handle of malleus
describe course of facial nerve?
connects to CNS at junction between pons and medulla.
travels in internal acoustic meatus in posterior cranila fossa. in base of skull in temporal bone (petrous part) in internal acoustic meatus and stylomastoid foramen
gives taste to anterior 2/3rd tongue and parasympathetcis supply to submandibular and sublingual and salivary glands
chorda tympani branch of facial nerve
thinnest skeletal muscle in body?
function of starpedius?
reduces stapes movement to pretect internal ear against excessive noise
what does tensor tympani do?
dampens the sound of chewing
muscle on forehead
muscled around eyes
2 parts of CN VIII
what does the otic capsule contain?
bony labyrinth which is fluid filled (perilymph)
what is suspended in the perilymph of the bony labryrinth?
membranous labyrinth, communicating sacs and ducts and endolymph
semiciruclar canals are part of the...?
snail looking thing