Hearing Loss

Question 1

What type of hearing loss is described?

Impaired sound transmission via external canal and middle ear ossicles to the foot of the stapes.

Answer 1

Conductive hearing loss

Question 2

What type of hearing loss is described?

Defects central to the oval window in the cochlea, cochlear nerve, or rarely more central causes.

Answer 2

Sensorineural hearing loss (sensory = cochlea, neural = cochlear nerve)

Question 3

What are the causes of conductive hearing loss?

Answer 3

1. External canal obstruction - wax, pus, debris, foreign body, congenital abnormality
2. Drum perforation - trauma, barotrauma, infection
3. Ossicular chain problems - otosclerosis, infection, trauma

Question 4

What are the causes of sensorineural hearing loss?

Answer 4

1. Ototoxic drugs - streptomycin, vancomycin, gentamicin, chloroquine, furosemide
2. Post-infective - meningitis, measles, mumps, flu, herpes, syphilis
3. Cochlear vascular disease - Meniere’s disease, presbycusis
4. Rare - acoustic neuroma, B12 deficiency, MS, brain metastases

Question 5

What is this describing?
Sudden loss of >30dB in 3 continuous pure tone frequencies over 3 days. Sudden/rapidly progressive. Usually unilateral. Partial/complete recovery in 30-65% of cases.

Answer 5

Sensorineural hearing loss

Question 6

What work-up investigations are done for any sudden sensorineural hearing loss?

Answer 6

1. Full history
2. Examine external auditory canal and tympanic membrane
3. Tuning fork tests
4. FBC, ESR/CRP, U&Es, LFTs, TSH, autoimmune profile, clotting, fasting glucose, cholesterol.
5. Audiometry +/- audiological brainstem responses

Question 7

What is the diagnosis in sudden sensorineural hearing loss with no cause found?

Answer 7

Idiopathic sudden sensorineural hearing loss (ISSNHL)

Question 8

What treatment is commonly given in sudden sensorineural hearing loss?

Answer 8

1. Prednisolone 80mg PO for 4 days tapered over 8 days.

2. Intratympanic dexamethasone rescue therapy in treatment failure.

Question 9

What is this a presentation of?
Early adult life, worse during pregnancy and menstruation, conductive deafness (better with background noise), tinnitus, mild transient vertigo.

Answer 9

Otosclerosis

Question 10

What is the pathophysiology of otosclerosis?

Answer 10

Autosomal dominant.

New bone forms around stapes footplate, leads to fixation and conductive hearing loss.

Question 11

What is the treatment for otosclerosis?

Answer 11

Hearing aid or surgical stapedectomy

Question 12

What is this a presentation of?
Older age, bilateral, high frequency sensorineural hearing loss, gradual loss. Hearing most affected with background noise.

Answer 12

Presbycusis - diagnose on pure tone audiogram

Question 13

What is the treatment for presbycusis?

Answer 13

Hearing aids