Ear Disease and Hearing Loss Flashcards
The tymphatic membrane/middle ear gives you a ____dB increase in sound pressure
30dB
Why, due to their eustachian tubes, are kids more likely to get OMEs and middle ear infections?
Smaller, more horizontal, doesn’t work as well
What does E COLI stand for?
Ear
Cochlear nerve
Olivary complexes
Laternal lemnisces
Inferior colliculus
What types of Hearing Loss are there?
- Conductive; pinna, outer/middle ear
- Sensorineural; start from nerve component (cochlea)
- Mixed
- Central Disorders; usually with age
What do we use to stage severity of a hearing loss?
An audiogram
Horizontal axis: different frequecies. The normal range of hearing 20Hz - 20kHz,
Vertical Axis: Measures the sound pressure. a 10dB increase = 100x the sound level. Therefore your sound pressure doubles every ~3dB. Normal is 0-20dB
- *Mild** 20-40dB
- *Moderate** 40-70dB
- *Severe** 70-90dB
- *Profound** >90dB
0 is a reference point, what 95% of healthy kid could hear.
What are the levels of hearing loss in NZ?
>10.3% degree of hearing loss
>6.6% report disability by hearing loss
>0.7% report diability due to deafness
What are the social consequences of hearing loss?
- speech and language deficits
- Learning difficulties
- auditory processing difficulties
- Academic achievement
- Low self-esteem and confidence
- social isolation
- reduced employment oppurtunities
- Safety: alarms etc
What are medical consequences of Hearing Loss?
- Middle ear disease and it’s complications
Cholesteatoma: skin inthe middle ear
WHat do you take during a history?
Age
Duration (>10 years loss of CNS stimulation. Also if born with you need to work quickly to not lose language)
Severity (life and audiometer)
Onset: rapid/gradual, constant/fluctuating
Precipitating Factors; noise (temporary or perm), trauma, drugs
Past medical and family history
Ass. Symptoms: tinnitus, vertigo, aural fullness, headaches
What is tinnitus?
Buzzing, whoosing, ringing sound of the ears, that isn’t organised and isn’t assoctiated with other psychosis issues.
What do we use to exam the ears?
- Otoscopy: to see the inner anatomy
- Clinical test of hearing: whisper test
- Tuning for testing: Webber and Rinne tests
Neurological Examination: cranial nerves, cerebellar function
General exam
What investigations do we do of the ear?
- Audiogram: usually a pure tone (frq test). Anything below 20dB is normal
- Otoacoustic emissions: ability of OHC to make their own sound
- ABR (auditory brainstem response): measures E COLI
- CT(conductive HL), MRI (Central HL)
- ENG: eye movements
- Blood tests: physillis
- Genetic testing
- Cardiac, renal and opthamology consult
Whats a few types of conductive hearing loss that you can get?
Exostoses: “surfers ear” Bony growths in the ear due to cold water exposure
What are the common findings of otitis media with effusion?
- Common in 1-4 year olds; only an issue of for >some weeks
- Eustachian tube dysfunction
- Infection/inflammation
- Negative pressure: like a thick silicone glue
- Effusion
What is mastoiditis?
Complication of otitis media, infects mastoid ear cells → abcyss
- Medial emergency: as abcyss is mm away from the brain, can break into the brain
- Hearing loss secondary
- Red lump behind the ear, ears pushed forward from the pressure.