hearing loss

Question 1

causes of exostosis

Answer 1

repeated exposure to cold water and wind

Question 2

what is exostosis

Answer 2

a benign bony growth in the external auditory canal, this is a form of conductive hearing loss

Question 3

what is a cochlear implany

Answer 3

rgically implanted device that provides people with severe to profound sensorineural deafness with a modified sense of sound.

Question 4

contradiction for cocnhlear implant

Answer 4

otitis media is a contraindication to a cochlear implant due to the risk of meningitis and tympanic membrane rupture.

Contraindications to consideration for cochlear implant:
Lesions of cranial nerve VIII or in the brain stem causing deafness
Chronic infective otitis media, mastoid cavity or tympanic membrane perforation
Cochlear aplasia

Relative contraindications:
Chronic infective otitis media or mastoid cavity infections
Tympanic membrane perforation
Patients that may be seen to demonstrate a lack of interest in using the implant to develop enhanced oral communication skills.

Question 5

how to assess suitability for cochlear implant

Answer 5

n children, audiological assessment and/or difficulty developing basic auditory skills.
In adults, patients should have completed a trial of appropriate hearing aids for at least 3 months which they have been objectively demonstrated to receive limited or no benefit from.

Question 6

causes if severe to profound hearing loss

Answer 6

In children
Genetic (accounts for up to 50% of cases).
Congenital e.g. following maternal cytomegalovirus, rubella or varicella infection.
idiopathic (accounts for up to 30% of childhood deafness).
Infectious e.g. post meningitis.

In adults
Viral-induced sudden hearing loss.
Ototoxicity e.g. following administration of aminoglycoside antibiotics or loop diuretics.
Otosclerosis
Ménière disease
Trauma

Question 7

prior to assess for the cochlear implant what should patients acheive

Answer 7

patients should have exhausted all medical therapies aimed at targeting any underlying pathological process contributing to the loss of hearing. In addition, they should have explored ‘conventional’ amplification strategies i.e. hearing aids and found the devices insufficient to allow functioning within daily life and/or support language development/maintenance.

Question 8

what should still be survivng for an implant

Answer 8

y the destruction or degeneration of the organ of Corti, it is essential that there are surviving spiral ganglion neurons to ensure the success of the implant. An assessment of the patient anatomy should be undertaken by an experienced otolaryngologist/skull base surgeon.

Question 9

complications of the implantation

Answer 9

infection, facial paralysis due to nerve injury intra-operatively, cerebrospinal fluid (CSF) leakage, and meningitis. To reduce the risk of meningitis as far as possible, it is recommended that all patients should have up-to-date vaccinations against Streptococcus and Haemophilus.

Question 10

post op what happens for implants

Answer 10

Patients are discharged for the post-operative physical recovery of the implantation site and generally return to outpatient clinic 3-5 weeks post-op for device stimulation.

Question 11

how does an implnat work

Answer 11

Externally, the microphone recognises the environmental sound and sends it to the sound processor. This, in turn, transforms the impulses received into a digital signal that which is then transferred to the transmitter coil. The transmitter coil conveys the signal to the internal components. Internally, a receiver, which magnetically connected to, and sits directly above the transmitter coil, and receives the impulses from the external apparatus which are then processed by a set of electrodes. The electrodes do the work that would be performed by the inner ear hair cells in a ‘normal’ ear. The brain can then process these signals to comprehend sound. Rechargeable batteries can be used to power the apparatus and life span depends upon usage and the individual device.

Question 12

risk of sudden-onset sensorineural hearing loss

Answer 12

permanent hearing impairment

Question 13

treatment of dden-onset sensorineural hearing loss

Answer 13

high-dose oral corticosteroids

Question 14

features sudden-onset sensorineural hearing loss

Answer 14

sudden
fullness
not painful no vertigo
normal otoscope

Question 15

what is presbycusis

Answer 15

Presbycusis describes age-related sensorineural hearing loss. Patients may describe difficulty following conversations

Audiometry shows bilateral high-frequency hearing loss

Question 16

what is otosclerosis

Answer 16

Autosomal dominant, replacement of normal bone by vascular spongy bone. Onset is usually at 20-40 years - features include:
conductive deafness
tinnitus
tympanic membrane - 10% of patients may have a ‘flamingo tinge’, caused by hyperaemia
positive family history

Question 17

drug ototxicity

Answer 17

Examples include aminoglycosides (e.g. Gentamicin), furosemide, aspirin and a number of cytotoxic agents

Question 18

acoustic neuroma/ vestibular schwannomas

Answer 18

Features can be predicted by the affected cranial nerves
cranial nerve VIII: hearing loss, vertigo, tinnitus
cranial nerve V: absent corneal reflex
cranial nerve VII: facial palsy

Bilateral acoustic neuromas are seen in neurofibromatosis type 2

Question 19

causes of perforated tympanic membrane

Answer 19

infection
barotrauma
direct trauma

Question 20

features of a perforated TM

Answer 20

hearing loss

mild pain

Question 21

management of perforated TM

Answer 21

no treatment is needed in the majority of cases as the tympanic membrane will usually heal after 6-8 weeks. It is advisable to avoid getting water in the ear during this time

it is common practice to prescribe antibiotics to perforations which occur following an episode of acute otitis media. NICE support this approach in the 2008 Respiratory tract infection guidelines

myringoplasty may be performed if the tympanic membrane does not heal by itself

Question 22

what is auricular haematoma

Answer 22

occur after direct trauma to the ear and is due to a build up of blood between the cartilage and perichondrium. This can restrict blood supply and lead to necrosis of the connective tissue.

Question 23

kicked in the ear
ear pain
persistent ringing
tender and swollen

Answer 23

auricular haematoma

Question 24

management of auricular haematoma

Answer 24

auricular haematomas need same-day assessment by ENT

incision and drainage has been shown to be superior to needle aspiration

Question 25

causes of tinnitus

Answer 25

meniere's 
otosclerosis
acoustic neuroma
hearing loss
drugs - Aspirin/NSAIDs
Aminoglycosides
Loop diuretics
Quinine

impacted ear wax
chronic suppurative otitis media

Question 26

which durgs cause tinnitus

Answer 26

quinine
aspirin
NSAIDs
aminoglycosides
loop diuretics

Question 27

when do you refer someone to ENT within 24 hours

Answer 27

Sudden onset (over 3 days or less) unilateral or bilateral hearing loss which has occurred within the past 30 days and cannot be explained by external or middle ear causes.

Unilateral hearing loss associated with focal neurology (such as altered sensation or facial droop).

Hearing loss associated with head or neck injury.

Hearing loss associated with severe infection such as necrotising otitis externa or Ramsay Hunt syndrome.

Question 28

what is vestibular schwannoma (acoustic neuroma)

Answer 28

intracranial tumors

cerebellopontine angle tumors

Question 29

history of vestibular schwannoma

Answer 29

vertigo
hearing loss
tinnitus
absent corneal reflex

Question 30

why are these features seen in vestibular schwanomma

Answer 30

1) cranial nerve VIII: vertigo, unilateral sensorineural hearing loss, unilateral tinnitus
2) cranial nerve V: absent corneal reflex
3) cranial nerve VII: facial palsy

Question 31

where are bilateral vestibular schwanommas seen

Answer 31

neurofibromatosis type 2

Question 32

Ix of choice for vestibular schwanomma/acoustic neuroma

Answer 32

MRI of the cerebellopontine angle

Question 33

what is exostosis

Answer 33

repeated exposure to cold water and wind which causes a benign bony growth in the external auditory canal, this is a form of conductive hearing loss