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Structures: Part Deux > LEC65: Our Ears > Flashcards

Flashcards in LEC65: Our Ears Deck (68)
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1
Q

greek, latin, olde english, pinna for ear?

A

greek: oto (otic)
latin: auris (auricular)

olde english: eare

pinna: from latin, feather, wing, fin

2
Q

identify the temporal bone

A
3
Q

parts of the temporal bone?

A

squamosal

zygomatic

mastoid

tympanic

4
Q

what is within temporal bone?

A

sensory organs for balance and hearing

5
Q

what connects to styloid process of temporal bone?

A

stylyhyoid ligament

stylomandibular ligament

styloglossus m (XII)

stylohyoid m (VII)

stylopharyngeus m (IX)

6
Q

what is different about a baby’s temporal bone?

A

no mastoid process - it’s a developmental feature

7
Q

where does internal acoustic meatus open?

A

into petrous part of temporal bone

8
Q

which region of skull is temporal bone in?

A

middle cranial fossa

9
Q

what is within the mastoid process here?

A

mastoid air cells

neumatized bone in the mastoid process

bone lessens with aging there - normal - air circulates. but can have infection spread here.

10
Q

what provides sensory innervation to inner ear canal? nerve and fiber type

what other nerves do you find in the inner ear canal?

A

GSA of CN VII, facial n

also see vestibular nerve, cochlear nerve - balance

11
Q

if facial nerve is knocked out when exits internal acoustic meatus, what is lost?

A

all function of VII

12
Q

if VII is knocked out distal to greater petrosal nerve, what remains / is lost?

A

retain lacrimal gland GVE

lose sublingual/submandibular gland GVE

lose taste to anterior 2/3 tongue SVA

lose facial expression SVE

13
Q

if VII is knocked out distal to chorda tympani, what is retained/lost?

A

retain:

lacrimal GVE (greater petrosal n)

sensation of inner ear GSA (n to stapedius)

taste to anterior 2/3 tongue SVA submandibular, sublingual glands’ GVE (chorda tympani)

lose:

facial expression SVE

14
Q

sensory ganglion of facial n?

A

geniculate ganglion

15
Q

where do motor branches of facial n traverse?

A

across parotid gland

then span out, do mm of facial expression

16
Q

what are our 6 ears?

A

external, middle, inner on each side of the head

17
Q

boundaries of each part of ear?

A

external: pinna - canal - tympanic membrane
middle: tympanic membrane - oval window
inner: deep w/in crevices of petrous

18
Q

parts of external ear?

A

1) auricle aka pinna - what we see on outside
2) external acoustic meatus - external ear canal, leads to tympanic membrane

19
Q

ID: helix, anti-helix, tragus, concha, pinna

A
20
Q

first arch syndrome re: ear? what might result?

A

poor developed meckel’s cartilage

poorly developed pinna

mandible underdeveloped

21
Q

functions of external ear?

A

capture, direct, amplify sound

dissipate heat

communicate / mood signaling

22
Q

what provides auricular sensation?

A

V - auriculotemporal branch

VII - posteiror canal wall

IX - medial, inner part of tympanic membrane (via tympanic n)

X - most of ear canal, part of outer surface of tympanic membrane (auricular br)

C2, C3 - greater auricular n

C2 - lesser occipital n

23
Q

where is sexual stimulation on ear? sexual suppression?

A
24
Q

what causes cauliflower ear?

A

blows, damage that separate cartilage of pinna from surrounding tissue

tissue fills with fluid so difficult for blood or other serous fluid to escape

25
Q

wax function in ears?

A

catches things coming in

works w/ sebaceous gland, keeps tympanic membrane moist, lubricated

26
Q
A

hairs sticking in to sebaceous glands

ceruminous glands v important to give moistening

27
Q

what is otitis externa

A

common, inflammation with external ear

28
Q

why might you cough when inserting something into the ear?

A

because major innervation is from a branch of X, vagus

this is vagal response

29
Q

what is otomorphology

A

study of the appearnce of the external ear

every person’s is different

can be used as a fingerprint substitute

30
Q

where is middle ear? what is its main property?

A

air-filled space

from tympanicmembrane laterally to lateral wall of inner ear medially

communicates w/ mastoid air cells & pharyngotympanic (eustachian) tube

31
Q

identify: pinna, ear canal, eardrum, middle ear, inner ear, eustachian tube

A
32
Q

ossicles of middle ear?

A

malleus

incus

stapes

33
Q

what is tympanic membrane a remnant of?

A

pharyngeal pouch of 1st branchial arch

34
Q

identify chorda tympani, incus, handle of malleus

A
35
Q

identify malleus

A
36
Q

what is the difference

A
37
Q

what is otitis media

A

build up of pressure in the middle ear, causes ear infection

very painful

38
Q

what might chronic otitis media cause?

A

tear in the tympanic membrane (ear drum)

may effect malleus, may effect entire hearing mechanism, may have scaring on tympanic membrane

39
Q

muscles of inner ear, their innervation, branchial arch derivation, function?

A

1) tensor tympani - V - arch 1 - dampen sounds, such as those produced from chewing
2) stapedius - VII - arch 2 - stabilize the stapes

40
Q

how does sound move from outside > inside?

A

sound through ear canal > hits tympanic membrane

tympanic membrane vibrates, virbation > malleus

malleus passes vibration to incus, passes virbation to stapes > voal window

> inner ear fluids

41
Q

what is smallest bone in human body?

A

stapes!

42
Q

branchial arch of upper portion of malleus and incus?

A

branchial arch I

43
Q

branchial arch of lower part of malleus and incus?

A

branchial arch II

44
Q

branchial arch of arcus of stapes?

A

arch II

45
Q

nerve of branchial arch II?

A

chorda tympani

46
Q

what are the joints between the ossicles called? what type of joints?

A

synovial joints:

1) incudomaller (malleus-incus)
2) incudostapedeal (incus-stapes)

47
Q

what is otosclerosis? what’s result?

A

if footplate of stapes becomes fused to oval window

lose hearing

48
Q

what part of eustachian tube enters middle ear?

A

bony portion of eustachian tube > middle ear, at nasopharynx, at rear of nasal cavity

49
Q

components of eustachian tube?

A

bony and cartilagenous portions

50
Q

function of eustachian tube?

A

does aeration- equilibration of pressure in middle ear

51
Q

describe difference between child/adult eustachian tube

A

child’s tube is horizontal, so children get infection easily

adults have more vertical tubes, so less likely to get otisis media

52
Q

most common childhood ailment in the US?

A

middle ear disease, otitis media

53
Q

areas of inner ear?

A

1) bony cavities (bony labyrinth)
2) membranous ducts & sacs (membranous labyrinth)

54
Q

what does bony labyrinth contain?

A

vestibule, semicircular canals, cochlea

cavities lined w/ periosteum, contain perilymph

55
Q

what does membranous labyrinth contain?

A

semicircular ducts, cochlear duct, utricle, saccule

spaces lined w/ endolymph

56
Q

where is inner ear lodged?

A

deep within petrous bone

57
Q

interaction btwn oval and round windows?

A

foot of stapes pushe in on oval window > helps push fluid around

round window pushes out, opposes action

58
Q

functional elements of inner ear?

A

hair cells

59
Q

what is on top of hair cells of inner ear? fxn?

A

stereocilia

highly sensitive, so pick up pressurs and convey info back to brain

have these in semicircular canal, cochlea

60
Q

how many semicircular canals?

A

3 on each side of head

61
Q

types of hearing loss

A

1) conductive hearing loss
2) sensorineural hearing loss

62
Q

what is conductive hearing loss caused by, how does it present?

A

caused by piercing, related activities

failure in efficient conduction of sound waves thru outer ear, tympanic membrane, or middle ear

63
Q

what is sensorineural hearing loss caused by, what does it damage?

A

caused by damage to hair cells - ie rock concerts - or diseas or brain trauma

damages: cochlear n, inner ear hair cells, and/or brain

64
Q

nerves > inner ear?

A

VII, facial

VIII, vestibulocochlear

65
Q

presbycusis?

A

major presentaiton of sensorineural hearing loss

age-related hearing loss

extremely common

66
Q

how do cochlear implants work?

A

insert into cochlea

stimulates damaged hair cells > stimulates back to nerves

67
Q

vestibular system diseases examples? what do we know about them?

A

balance disorder such as meniere’s disease, labyrinthitis, vertigo

know fluid compositions in perilymph and endolymph are problematic but don’t understand disease process

68
Q

what is our oldest evolutionary sense?

A

balance