ENT (A) pre-work

Question 1

Two main physiological functions of ear

Answer 1

• Hearing
• Balance

Question 2

What happens in terms of sound waves, vibrations and electrical energy for us to hear?

Answer 2

• Pinna, EAM and tympanic membrane collect sound waves and transmit them
• Ossicles - malleus, incus and stapes vibrate against eachother amplifying the sound waves
• Stapes vibrates at oval window
• This causes fluid called endolymph to move in cochlea
• Fluid movement moves sterocilia in cochlea organ of conti
• = transmits APs so electrical energy via VC nerve to brain to hear - primary auditory cortex in temporal lobe

Question 3

Symptoms of problems with ear

Answer 3

• Otorrhoea - discharge
• Otalgia
• Hearing loss - sensorineural or conductive
• Tinnitus
• Vertigo
• Facial nerve palsy - goes through petrous bone

Question 4

Clinical exam techniques for ear

Answer 4

• Inspect - external ear, EAM and tympanic membrane using otoscope. Also inspect mastoid - is ear pushed forwards?
• Palpate around ear and mastoid process - tenderness?, inc pre and post auricular lymph nodes, palpate tragus - otitis externa?
• Weber - vibrating tuning fork in centre of head - is it symmetrical? louder on one side?
• Rinne - place on mastoid process tell me when you can’t hear, then place it in front of ear - can you hear it now?

Question 5

Conductive vs sensorineural hearing loss

Answer 5

• Conductive - problem with external or middle ear
• Sensorineural - problem with inner ear - cochlea

Question 6

Weber and Rinne test results

Answer 6

Weber test:
* Normally sound should be midline
* In conductive loss, sound lateralises towards affected ear (eg if loss in R, sound would be more R sided) as there is loss of ambient noise
* In sensorineural, sound lateralises away from affected ear (so if R affected, sound sounds louder in L ear)

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Rinne
* AC normally better than BC
* In conductive BC is better than AC
* In sensorineural conduction is normal so AC is better than BC

Question 7

What is a pure tone threshold?

Answer 7

• Pure tones are sounds of single frequencies
• Pure tone threshold is the softest level (lowest volume) at which a person can hear a pure tone
• Threshold is usually measured in decibles
• Noises are played at different frequencies and decibles to establish which ones you can and cannot hear
• The lower the threshold in decibles the more sensitive your ears are to that frequency (so better at hearing it as it is lower volume but you can still hear it)

Question 8

How is air conduction measured?

Answer 8

• Presenting a pure tone to the ear through an earphone and measuring the lowest intensity in decibels (dB) at which this tone is perceived 50% of the time.
• It is measured at 250, 500, 1000, 2000, 4000 and 8000

Question 9

How is bone conduction measured?

Answer 9

• Bone vibrator on the mastoid process
• Tested at 500-4000Hz

Question 10

What is masking?

Answer 10

• Presenting a sound to the non-test ear
• Preventing it from detecting the sound given to the test ear
• Prevents cross hearing which occurs from bone conduction to contralateral cochlea

Question 11

How would high frequency hearing loss affect someone?

Answer 11

• May be unable to hear birds
• Some alarms
• Trees rustling
• Sounds like ‘th’ ‘f’ ‘s’ ‘ee’

Question 12

How would low frequency hearing loss affect someone?

Answer 12

• May not be able to hear running water/tap dripping
• Dog barks
• Certain sounds eg ‘v’, ‘z’, ‘j’

Question 13

How can deafness in childhood affect someone?

Answer 13

• Affect speech and language development
• Following directions in loud/noisy places - difficult
• Making friends and interacting with others - more difficult
• Learning to read
• Need specialist education or changes - eg sit at front of class, teacher not turn their back while talking etc

Question 14

Impacts of hearing loss with older age + dementia

Answer 14

• Increase risk of confusion
• Increases dementia risk itself
• Misdiagnosis of dementia
• Harder to communicate with loved ones

Question 15

Impacts of hearing loss and visual impairement

Answer 15

• Higher risk of dementia?
• Social isolation - difficulty comunicating
• Lack of public acceptance

Question 16

Red flags for ENT conditions

Answer 16

• Unilateral hearing loss/tinnitus that is persistent - routine referral
• Discharging ears esp in immunocompromised (malignant otitis externa)
• Facial nerve palsy
• Blood stained mucous from nose
• CSF leak
• Dysphagia - progressive
• Unilateral rhinorrhoea - foreign body - refer ENT
• Sudden hearing loss - acoustic neuroma?
• Pain unproportional to ear appearance - malignant otitis externa
• Recurrent ear infections - refer
• Boggy swelling behind ear and ear pished forward - mastoiditis - admit for IV abx
• Epistaxis that is not stopping -
• Swollen eyes during sinusitis - periorbital cellulitis - admit
• Tonsillits that cannot swallow - admit
• Unilateral jaw locking and painful tonsil, otalgia - Quinsy
• Unwell child sat up and forwards, stridot, drooling - Epiglottitis - DO NOT LOOK IN MOUTH, DO NOT UPSET CHILD
• Persistent hoarseness voice >3 weeks = larynx cancer
• Pulsatile tinnitus
• Any neurological symptoms
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