ENT: Hearing, deafness and tinnitus Flashcards
what is conductive deafness?
Disease of external or middle ear prevents sound wave from getting to cochlea.
e. g.
- ear wax
- Osteomata
- Congenital absence of external ear canal
- fluid in middle ear e.g. blood (Haemotympanum)
- problems with ossicles
what is sensorineural deafness?
Due to damage / abnormality of cochlea, cochlear nerve or central centres of hearing
e. g.
- Presbycusis (acing)
- Death of hair cell’s reduces sensitivity of cochlea.
- congenital (cochlear implant)
which type of deafness is treated with hearing aids?
sensorineural deafness
why type of deafness can be accelerated by by chronic excessive noise exposure?
sensorineural deafness
The loss of hair cells can be accelerated by chronic excessive noise exposure
what investigations can you conduct to diagnose deafness?
- audiogram
- rinnes and webers test (You need a 512hz tuning fork)
describe Rinne’s test for hearing?
the tuning fork is placed on the mastoid bone (bone conduction) and then placed next to the external ear (air conduction).
Usually air conduction is heard louder than bone conduction and this is a positive Rinne’s test.
If bone conduction is louder than air conduction, this is a negative Rinne’s test and indicates conductive hearing loss in that ear.
describe Weber’s test for hearing?
the tuning fork is placed on the forehead. The patient is asked in which ear the sound is louder. If the patient hears the sound equally in each ear or cannot localise, this is normal and is termed a mid-line Weber’s.
if the patient hears the sound louder in the right ear, then this indicates either a right conductive or a left sensorineural hearing loss.
what is tinnitus?
Tinnitus is the perception of sounds in the absence of external auditory stimulus. It is a symptom, not a diagnosis.
what is the management for tinnitus?
- treat underlying cause (e.g. hearing loss)
- education and counselling
- cognitive behavioural therapy
- “masking” devices
