Hearing Loss

Question 1

Causes of conductive hearing loss (5)

Answer 1

obstruction

perforation

problems with ossicular chain: otosclerosis

impaired eustachian tube ventilation e.g. effusion from nasopharyngeal ca.

petrous temporal bone fracture

Question 2

Pathology of sensorineural hearing loss (3)

Answer 2

defects to:

• oval window of cochlea (sensory)
• cochlear nerve (neural)
• central pathways

Question 3

Causes of sensorineural hearing loss (6)

Answer 3

ototoxic drugs:

• gent, vanco, streptomycin
• chloroquine/hydroxychloroquine
• furoesmide, cisplatin

post-infection:

• meningitis, measles, mumps, flu
• herpes, syphilis

meniere’s

acoustic neuroma

presbyacusis

cochlear vascular disease

Question 4

Auditory neuropathy spectrum disorder

Answer 4

disorder in transmission of sound from inner hair cells to brainstem resulting in impaired discrimination of speech beyond what is expected.

Question 5

Auditory processing disorder

Answer 5

disorder of central auditory pathways resulting in impaired COMPREHENSION; hearing is technically intact

Question 6

Neonatal deafness screening

Answer 6

ALL children screened either via otoacoustic emissions or via audiological brainstem responses.

Question 7

Congenital causes of central hearing loss (3)

Answer 7

hyperbilirubinaemia/kernicterus
hypoxia
ventricular haemorrhage

Question 8

Congenital causes of conductive hearing loss (4)

Answer 8

physical anomalies

congenital cholesteatoma

Treacher-Collins:

• downward slanting eyes
• drooping lower eyelid
• micrognathia
• malformed ears

Pierre-Robin>congenital facial abnormalities

Question 9

Congenital causes of sensorineural hearing loss (5)

Answer 9

AD:

• Waardenburg: heterochromia, widely spaced eyes, white tuft of hair and white patch on forehead
• Klippel-Feil

AR:

• Pendred:goitre
• Usher’s: retinitis pigmentosa
• Jevell-Lange-Nielson: QTc

X-linked:

• Alports: GN
• Turner’s

congenital infection: rubella, syphillis, toxoplasmosis GBS, CMV

ototoxic drugs

Question 10

Peri/post-natal causes of hearing loss (8)

Answer 10

anoxia
birth trauma
cerebral palsy
kernicterus
ototoxic drugs
lead
skull fracture
meningitis

Question 11

Mx of childhood deafness (2)

Answer 11

Cochlear implant:

• under GA
• directly stimulates acoustic nerve
• better if language already established
• requires post-op rehab as noises perceived differently
• need pneumococcal vaccine beforehand to prevent meningitis

Bone-anchored hearing aid:

• augments bone conduction
• better for conductive or unilateral hearing loss or for those who don’t like in-ear hearing aids

Question 12

causes of conductive hearing loss in children (3)

Answer 12

wax:

• olive oil 1st line
• suctioning 2nd line

otitis media

otitis media w. effusion (glue ear):

• Hx of recurrent otitis media
• otoscopy can be normal
• tympanometry shows flattened curve due to non-compliant membrane

Question 13

Mx of deafness in adults (3)

Answer 13

exclude dangerous cause:

• acoustic neuroma
• cholesteatoma
• effusion from nasopharyngeal ca.

palliatve: hearing aid
definitive: NB cochlear implants can be fitted up to 70yrs

Question 14

Causes of sudden sensorineural hearing loss in adults (8)

Answer 14

noise exposure
gentamicin toxicity
acoustic neuroma
vasculopathy
mumps
MS
TB
rarer: stroke, sarcoid, takayusu's, Chlamydia, pneumonia, immune complexes/Abs

Question 15

Mx of sudden sensorineural hearing loss in adults (5)

Answer 15

get ENT help

find cause:cultures, Abs, TSH, glucose, cholesterol, ESR, FBC, LFT, viral titres, audiology, evoked response audiometry

MRI/CT

audiometry and brainstem evoked response

Steroids may help if given immediately

Question 16

-ve prognostic factors for sudden sensorineural hearing loss (4)

Answer 16

<15/>65yrs
raised ESR
vertigo
hearing loss in opposite ear

Question 17

Common causes of conductive hearing loss in adults (3)

Answer 17

wax

otitis media

otitis externa

Question 18

Other causes of deafness in adults (6)

Answer 18

otosclerosis

pesbyacusis

post ear surgery

trauma-fractured petrous temporal bone/dislocated ossicles

tumours

cholesteatoma

Question 19

Features and pathology of otosclerosis (3)

Answer 19

AD w. incomplete penetrance

more common in women

abnormal growth of vascular, spongy bone

Question 20

Sx of otosclerosis (4)

Answer 20

onset at 20-40yrs

progressive conductive hearing loss made worse by PREGNANCY, menstruation and menopause

tinnitus

vertigo

Question 21

Mx of otosclerosis (4)

Answer 21

fenestration

fluoride may inhibit progression

hearing aids

surgery to replace middle ear (can dmg VIIth nerve)

Question 22

Pathology and Rx of presbyacusis (4)

Answer 22

progressive, age-related, sensorineural hearing loss due to noise toxicity.

due to loss of hair cells

Sx worse in presence of background noise

Rx w. hearing aids