6.1 The Ear Flashcards Preview

Semester 4- Head and Neck > 6.1 The Ear > Flashcards

Flashcards in 6.1 The Ear Deck (29):
1

What makes up the external ear?

Pinna
External auditory canal
Tympanic membrane

2

What makes up the middle ear?

Ossicles
Muscles
Eustachian tube
Mastoid air cells
Facial nerve (chorda tympani)

3

What makes up the inner ear?

Cochlear
Vestibular compartment

4

What is a pinna haematoma?

Haematoma between the cartilage and the perichondrium which prevents oxygenation of tissue resulting in avascular necrosis

5

What is cauliflower ear?

Ear collapses in and structure is lost after repeated injuries (eg rugby injuries)

6

Which glands form ear wax?

Serumium glands

7

What is the function of ear wax?

Cleans the ear

8

What is the tympanic membrane also known as?

Ear drum

9

Which way does the cone of light point on the tympanic membrane?

Inferiorly and anteriorly

10

Give 2 causes of tympanic membrane rupture

Trauma
Infection

11

Name the 3 bones of the middle ear

Malleus
Incus
Stapes

12

What type of joint joins the bones of the middle ear?

Synovial joint

13

What is the function of the eustachian tube?

Equalises the pressure between the ear and the GI tract

14

What is the function of the mastoid air cells?

Aerate the middle ear

15

Name the 2 muscles in the middle ear

Tensor tympani and the stapedius

16

What nerve innervates the tensor tympani?

CN V2 branch

17

What nerve innervates the stapedius muscle?

Facial nerve

18

Why are children more at risk of eustachian tube dysfunction?

Tube is shorter and wider and so more at risk of infections travelling up from the mouth

19

What is otitis media?

Inflammation of the middle ear leading to retraction of the ear drum.

20

What is glue ear?

Accumulation of thick effusions behind the ear drum

21

What is mastoiditis?

Inflammation of the mastoid air cells. Pus forms and increases the pressure in the ear

22

What is cholesteatoma?

Negative ear pressure causes retraction of the tympanic membrane. Dead cells accumulate as a necrotic mass (cholestoma). Lytic enzymes are released and erodes the middle ear

23

What bone surrounds the inner ear?

Temporal bone

24

Which part of the inner ear allows hearing?

Cochlear

25

How does the cochlear work?

Radial structure with sensory cells. The sensory cells have a given frequency at which they will resonate. This produces an electrical signal which the brain recognises as sound

26

Which part of the ear controls balance?

Vestibular compartment- utricle, saccule, 3 semi-circular canals

27

How does the vestibular compartment control balance?

Fluid in the semicircular canals and the saccule moves and hits the collagenous matrix. Depending on which area of the vestibular can detect the fluid, the brain can work out its orientation

28

What is BPPV?

Benign Positional Paroxysmal Vertigo
Extra sediment in the inner ear fluid moves slower than the fluid. Eg. When the head turns the fluid moves so the brain recognises the movement. However the sediment still moves even when the body has stopped. Person feels as if they are still moving even when they are not

29

What is Meniere's disease?

Too much fluid in the inner ear so everything is overstimulated