Inner Ear

Question 1

Briefly describe the mechanism of hearing.

Answer 1

Sound enters ear, through the auditory canal, hits the tympanic membrane which vibrates and creates pressure which is transmitted through the ossicles.

Question 2

Which part of the ear collects sound?

Answer 2

Outer ear

Question 3

Which part of the ear amplifies sound?

Answer 3

Middle ear- transforms acoustic energy from medium of air into medium of fluid

Question 4

What is conductive hearing loss?

Answer 4

Hearing loss due to issues with the outer or middle ear

Question 5

What would be the maximum level of hearing loss if the sensoneural function is maintained?

Answer 5

60dB

Question 6

Which part of the inner ear responds to the change of pressure due to hearing?

Answer 6

Cochlea

Question 7

How does the middle ear amplify sound?

Answer 7

Area effect of the tympanic membrane as go from wide surface area of the membrane to a much smaller area of the stapes footpath.

Question 8

What is the ratio of surface area from the tympanic membrane to the stapes footpath?

Answer 8

17:1

Question 9

What is the job of the pinna?

Answer 9

Part of the external ear which collects soundwaves

Question 10

Which group of bones can be found in the middle ear?

Answer 10

Ossicles- malleus, incus and stapes

Question 11

What do the ossicles found in the middle ear do?

Answer 11

Pass the vibrations from the outer ear to the inner ear by increasing/amplfying pressure.

Question 12

Why does there need to be an increase in pressure before the vibrations go into the inner ear?

Answer 12

Inner ear contains liquid rather than aid so high pressure is required to move vibrations

Question 13

Describe briefly what the cochlea of the inner ear does.

Answer 13

Converts vibrations into electrical signals which go to the brain via cochlear nerves

Question 14

Which cells activate the afferent nerves of the cochlea?

Answer 14

Inner hair cells

Question 15

How does volume of sound affect the number of inner hair cells which will be activated?

Answer 15

Quieter the sound, the more inner hair cells will be activated

Question 16

What is meant by the tonotopic arrangement of hair cells on the basolateral membrane?

Answer 16

Every frequency of sound has a place on the basolateral membrane which is sensitive to that particular frequency

Question 17

Tuning forks can be used to test levels of hearing.
What can tuning forks help to differentiate between?

Answer 17

Conductive hearing loss and sensorineural hearing loss

Question 18

Which tuning fork test can test both ears?

Answer 18

Weber test- a test used to diagnose unilateral hearing loss and distinguish between conductive and sensorineural hearing loss

Question 19

Which tuning fork test is used to determine hearing loss in one ear

Answer 19

Rinne

tests one ear ag a time but doesn’t test unilateral hearing loss

Question 20

Describe how Weber’s test can determine which side of hearing loss is worst.

Answer 20

Tuning fork gets hit central to the patient, the side they hear the ding lounder on is the side with better hearing in cases of conductive hearing loss.

Question 21

If there is sensorineural hearing loss, will the patient hear noises louder or quieter in the affected ear?

Answer 21

Louder

->practice humming and then blocking one ear, blocked ear is louder

Question 22

In those with conductive hearing loss, will the patient hear noises louder or quieter in the affected ear?

Answer 22

Quieter

Question 23

What physical properties of sound would be useful in the assessment of hearing ability?

Answer 23

Frequency
Volume

Question 24

Describe what puretone audiometry measures.

Answer 24

Determines the tones a person can hear at selected pitches/frequencies.
Earphones are worn so info can be obtained for each ear.

Question 25

What is greater- air conduction perception or bone conduction perception?

Answer 25

Bone conduction perception

Question 26

Which type of audiometry might be done with young children who cannot communicate or those with learning disabilities?

Answer 26

Play audiometry ->this involves the child putting a toy in a certain place whenever they hear a sound e.g. dropping a counter in connect four

Question 27

Which type of audiometry is used for very young children who cannot understand or communicate?

Answer 27

Visual reinforcement audiometry ->monitors a child's reaction to hearing noise e.g. turning to see where the noise is coming from

Question 28

What are otoacoustic emissions?

Answer 28

Sounds given off by the ear when the cochlea is stimulated by sound.

Question 29

What happens when sound stimulates the cochlea?

Answer 29

Outer hair cells vibrate which produces an echo back to the middle ear

Question 30

What is doe is Emissions Testing?

Answer 30

A small probe is used to test the vibrations given at the back of the ear

Question 31

People with normal hearing produce emissions. At which levels of hearing loss are emissions not produced?

Answer 31

Hearing loss greater than 25-30dBs

Question 32

When may an OAE test (otoacoustic emissions test) be carried out?

Answer 32

As a part of new-born hearing screening programme

Question 33

What does Tympanometry help with?

Answer 33

Detects: -fluid in the middle ear -perforation of eardrum -wax blocking ear canal

Question 34

How does Tympanometry allow for the detection of wax, fluid or perforation?

Answer 34

Pushes air pressure into the ear canal making the eardrum move back and forth. Test measures pressure and mobility of the middle ear to create a tympanogram.

Question 35

What are some of the ways to manage hearing loss?

Answer 35

Surgery Sound amplification Direct stimulus of cochlea nerve cells

Question 36

What may be worn to help with the amplification of sound?

Answer 36

A hearing aid

Question 37

What would be used for people with difficulties hearing low and mid frequencies?

Answer 37

Full exclusive hearing aid

Question 38

What would be used for people with difficulty hearing higher pitched sounds?

Answer 38

Open fit hearing aid

Question 39

Describe what is used for hearing if someone does not have an ear canal.

Answer 39

Bone anchored hearing aid may be used. Hearing via bone conduction as sound conducts through the skull to the cochlea.

Question 40

What might be given to someone with severe sensorineural hearing loss?

Answer 40

Cochlear implant (essentially a very strong hearing aid).

Question 41

What is the name of the part of the inner ear responsible for balance?

Answer 41

Vestibule

Question 42

What does the vestibule contain?

Answer 42

2 otolith organs

Question 43

Name the two otolith organs found in the vestibule.

Answer 43

Utricle Saccule

Question 44

What is the endolymphatic sac?

Answer 44

Sac filled with endolymph

Question 45

Name the sensory epithelium of the utricle and saccule.

Answer 45

Macula

Question 46

How is the macula orientated in the utricle compared to the saccule.

Answer 46

Horizontally orientated in the utricle Vertically orientated in the saccule.

Question 47

Which membrane are the cilia of hair cells of the ear embedded in?

Answer 47

Otolithic membrane

Question 48

What is the function of the otolith organs?

Answer 48

Sense gravity and linear acceleration

Question 49

What are otoliths?

Answer 49

Calcium carbonate crystals

Question 50

What is the role of the cristra in the ear?

Answer 50

Sensory organ of rotation

Question 51

What is the name of the extended area at the end of each semi-circular canal of the ear?

Answer 51

Ampullae

Question 52

What do the ampullae contain?

Answer 52

Crista

Question 53

Why is the movement of kinocilia, crista and ampullae important?

Answer 53

Sets up the vestibulo-ocular reflex.

Question 54

What is the vestibulo-ocular reflex?

Answer 54

Allows us to maintain a stable image of the world as we engage in movements such as walking

Question 55

Name the three systems which help to maintain balance.

Answer 55

Visual Vestibular Proprioceptive

Question 56

Name three clinical conditions of the inner ear which can affect balance.

Answer 56

Benign Paroxysmal Positional Vertigo Vestibular Neuritis Meniere's Disease

Question 57

What is the most common cause of the utricles (which are set in the otoliths/calcium carbonate crystals) breaking off?

Answer 57

Old age

Question 58

List some other reasons the utricles can break off.

Answer 58

Trauma Meniere's disease Vestibular neuritis

Question 59

Which semi-circular canal is most commonly affected by getting otoliths in there when they shouldn't be?

Answer 59

Posterior semi-circular canal

Question 60

What can happen with there is otoliths where there shouldn't be?

Answer 60

Vertigo

Question 61

What is vertigo?

Answer 61

The sensation of spinning when staying still

Question 62

What happens to the eyes in vertigo?

Answer 62

Involuntary movement of the eyes

Question 63

How does the involuntary eye movement differ in vertigo?

Answer 63

The eyes will move differently depending which canal has the otoliths.

Question 64

What happens if the otoliths is in the horizontal canal?

Answer 64

Horizontal nystagmus- eyes move side to side

Question 65

What happens if the otoliths is in the posterior canal?

Answer 65

Vertical nystagmus- eyes move vertically and twists

Question 66

What is the name of the procedure that can help get rid of a loose body in the ear?

Answer 66

Epley manoeuvre

Question 67

Describe the Epley manoeuvre.

Answer 67

Turning head in a series of movements using gravity to dislodge otoliths (calcium carbonate crystals).

Question 68

Which manoeuvre can help to identify vertigo the type of vertigo?

Answer 68

Dix-Hallpike maneouvre ->gal you saw this on work experience at LGP...remember there was a calcium stone in a women's ear so they did this to try and see if she got dizzy???

Question 69

Describe the Dix-Hallpike manoeuvre

Answer 69

Patient sits on examination bed w extended legs and the head slightly turned towards affected ear. Then the clinician swiftly lies the patient down w their head hanging off the table to check for vertigo.

Question 70

Is BBPV (benign paroxysmal positional vertigo) long or short lasting?

Answer 70

Short lasting, as long as otolith is removed

Question 71

Describe what someone with vestibular neuritis may experience.

Answer 71

Severe vertigo for hours, can cause nausea and vomiting q

Question 72

Is there hearing loss with vestibular neuritis?

Answer 72

Rarely

Question 73

What happens to nystagmus with time?

Answer 73

It fades For example, only seen in those with vestibular neuritis in the early stages.

Question 74

Is vestibular neuritis a one off or long term thing?

Answer 74

One off

Question 75

If hearing loss is present with the severe vertigo, nausea and vomiting, what may be the cause?

Answer 75

Mumps, measles, infectious mononucleosis ('mono')

Question 76

Describe the classic triad seen in those with Meniere's disease.

Answer 76

Vertigo Unilateral hearing loss Tinnitus

Question 77

Does Meniere's Disease come on in episodes or is it continuous?

Answer 77

Episodes which can come in clusters. Can last 30 mins up to 24hrs

Question 78

What causes Meniere's Disease?

Answer 78

Not fully known ->histology suggests increase of endolymph, known as endolymphatic hydrops

Question 79

Which common condition can give people intermittent vertigo?

Answer 79

Migraines