ENT - Deafness

Question 1

Congenital causes

Answer 1

• Maternal rubella or cytomegalovirus infection during pregnancy
• Genetic deafness (autosomal recessive or autosomal dominant)
• Down’s syndrome

Question 2

Perinatal causes

Answer 2

Prematurity
Hypoxia during or after birth

Question 3

After birth

Answer 3

Jaundice
Meningitis and encephalitis
Otitis media or glue ear
Chemotherapy

Question 4

Signs

Answer 4

Parental concerns about hearing or with behavioural changes associated with not being able to hear:
- Ignoring calls or sounds
- Frustration or bad behaviour
- Poor speech and language development
- Poor school performance

Question 5

Screening test

Answer 5

The UK newborn hearing screening programme (NHSP) tests hearing in all neonates
- This can identify congenital hearing problems early

Question 6

Investigations

Answer 6

Audiometry
- Under 3: tested by looking for a basic response to sound
- Older children can be tested properly with headphones and specific tones and volumes
- Hearing is tested in both ears separately. Both air and bone conduction are tested separately. The following symbols are used to mark each of these separate measurements:
X – Left sided air conduction
] – Left sided bone conduction
O – Right sided air conduction
[ – Right sided bone conduction

Results recorded on audiogram which can help identify and differentiate conductive and sensorineural hearing loss.

Question 7

Sensorineural hearing loss

Answer 7

Where there is problems with the sensory system or verstibuar cochlear nerve. The sound is reaching the inner ear but cannot be sensed properly or transmitted to the ear properly.
Both air and bone conduction readings will be more than 20 dB.
This may only affect one side, one side more than the other or both sides equally

Question 8

Conductive hearing loss

Answer 8

In conductive hearing loss, sound can travel through bones but is not conducted through air due to pathology along the route into the air.
Bone conduction readings will be normal (between 0 and 20 dB), however air conduction readings will be greater than 20 dB on the chart.

Question 9

Mixed hearing loss

Answer 9

Both air and bone conduction readings will be more than 20 dB, however there will be a difference of more than 15 dB between the two (bone conduction > air conduction)

Question 10

Management

Answer 10

Multidisciplinary team is required for support with hearing, speech, language and learning:
Speech and language therapy
Educational psychology
ENT specialist
Hearing aids for children who retain some hearing
Sign language