Ear & Auditory Tube

Question 1

Lateral 1/3 is?

Medial 2/3 is?

Answer 1

1. cartilagenous

2. bony

Question 2

external accoustic meatus contains what?

Answer 2

hairy skin and Cerumen glands: prevent maceration with water

Question 3

What 2 nerves innervate the ear?

Answer 3

Vagus

V3 auriculotemporal nerve

Question 4

V3 auriculotemporal nerve innervates what in the ear?

Answer 4

anteriosuperior

external surface of tympanic membrane

Question 5

Vagus innervates what in the ear?

Answer 5

posterioinferior inner ear

Question 6

what’s the implication of V3 auriculotemporal nerve?

Answer 6

since part of trigeminal nerve, can have reerred pain from other areas like tooth to ear etc.

Question 7

what’s the imprint on the tympanic membrane lateral surface?

Answer 7

handle of malleus

Question 8

what shape is the tympanic membrane ?

Answer 8

concave externally

convex internally

Question 9

why is the cone of light in the tympanic membrane important where should it be?

Answer 9

Antero-Inferior

shows the concavity, clinical sign

Question 10

2 areas of middle ear are?

Answer 10

1. epitympanic recess (to mastoid air cells)

2. tympanic cavity proper

Question 11

what’s bad about infections in the middle ear?

Answer 11

can get into epitympanic recess, hard to drain, get into mastoid air cells. cause problems

Question 12

differences in infant and adult Eustachian tube?

Answer 12

infant more horizontal = less drainage = more otitis media

Question 13

cleft palate more likely to cause?

Answer 13

more eustuchian tube problems/otitis media

Question 14

which ossicles is attached to tympanic membrane?

Answer 14

handle of malleus

Question 15

which ossicle is attached to oval window?

Answer 15

stapes

Question 16

what two muscles dampen sound? innervations?

Answer 16

Stapedius: Seventh nerve (Facial)

Tensor Tympani: Trigeminal (trigeminal)

Question 17

what conditions don’t allow dampening of sound, why?

Answer 17

acoustic neuromas that compress trigeminal/facial nerve palsies

Question 18

Chorda tympani part of?

Answer 18

facial nerve

Question 19

what is the promontory?

Answer 19

basal turn of the cochlea

Question 20

facial nerve emerges where?

Answer 20

stylomastoid foramen

Question 21

what vital vessel is close to middle ear?

Answer 21

internal carotid

Question 22

what are the two labyrinths in the inner ear what fluid do they contain?

Answer 22

Bony Labyrinth: perilymph

Membranous labyrinth: endolymph

Question 23

bony labyrinth is located?

Answer 23

petrous part of temporal bone

Question 24

what contains the sensory receptros for hearing?

Answer 24

cochlear duct

Question 25

what senses static equilibrium?

Answer 25

utricle

saccule

Question 26

what senses dynamic equilibrium?

Answer 26

ampulla of the semicircular ducts

Question 27

utricle

saccule senses what?

Answer 27

static equilibrium

Question 28

ampulla of the semicircular ducts senses?

Answer 28

dynamic equilibrium

Question 29

where in the cochlea are high and low frequencies detected?

Answer 29

High Freq: base

Low Freq: apex of cochlea

Question 30

Saccule is vertical or horizontal?

Answer 30

Vertical

Question 31

Utricle more vertical or horizontal?

Answer 31

Horizontal