Auditory

Question 1

Conductive deafness

Answer 1

Due to disease in the middle ear interfering with transmission of sound to the cochlea
Deaf to ordinary air conduction but not bone conduction

Question 2

Sensorineural deafness

Answer 2

Due to injury or degeneration of the nerve elements on the cochlea or auditory nerve
Deaf to both air and bone conduction

Question 3

Bone conduction

Answer 3

Base of a tuning fork held firmly to subject’s skull, the sound can reach the cochlea independently of the middle ear

Question 4

Rinne’s test

Answer 4

Sound travels through the mastoid process after being lost at pinna in a BLOCKED ear but not in an unblocked ear

Question 5

Weber’s test

Answer 5

If ear is one ear is blocked, the sound of resonating tuning fork will be much LOUDER in the BLOCKED ear
Ambient noise (air conduction) masks bone conducted sound in unblocked ear

Question 6

Causes of sensorineural hearing loss

Answer 6

Damage to inner ear (congenital, infection)
Loss of or damage to hair cells due to toxins (furosemide)
Brainstem/nerve damage - neural pathways (processing)
Peripheral damage - presents as monaural hearing loss
Central damage - often presents as binaural hearing loss due to bilateral pathways

Question 7

Presbycusis

Answer 7

Age related hearing loss
Usually very gradually
Affects both ears equally

Question 8

Causes of conductive hearing loss

Answer 8

Physical damage to, or blockage of outer and/or middle ear
Infection/fluid in middle ear
Damage to tympanic membrane (ruptured eardrum)
Otosclerosis - excessive bone growth/deposition around ossicles