Hearing loss Flashcards
Conductive hearing loss & its mechanisms
Mechanical disruption of the external
auditory canal or middle ear
Mechanisms:
1. Obstruction
2. Mass loading
3. Non-compliant structures
4. Discontinuity of structures
Sensorineural hearing loss & its mechanisms
Deficit in the inner ear (sense) or central nervous system auditory pathway (neural)
Mechanisms:
1. Deterioration of cochlea – usually loss
of hair cells in Organ of Corti
> ____% of childhood hearing impairment is thought to be hereditary
50
Nonsyndromic vs. Syndromic hearing loss
- Nonsyndromic hearing loss: hearing loss is the only clinical abnormality
- Syndromic hearing loss: in which hearing loss is associated with anomalies in other organ systems
_____: retinitis pigmentosa & hearing
loss
Usher syndrome
______: pigmentary
abnormality (hair, skin, & nails) & hearing loss
Waardenburg syndrome
____ → thyroid organification
defect & hearing loss
Pendred syndrome
____ → renal disease & hearing loss
Alport syndrome
_____ → prolonged
QT interval & hearing loss
Jervell & Lange Nielson syndrome
Ototoxic Medications
- Aminoglycoside antibiotics: Gentamicin, Amikacin, Neomycin, Streptomycin
- Other antibiotics: Vancomycin, Erythromycin
- Antimalarials: Chloroquine, Quinine
- Platinum-based chemotherapy agents: Cisplatin, Carboplatin
- Loop diuretics: Furosemide, Torsemide
- Nonsteroidal anti-inflammatory drugs: Aspirin, Ketorolac, Ibuprofen
Hearing Loss presentation
- Sudden, unexplained hearing loss
- Gradual painless hearing loss
- Bilateral or unilateral
- Deficits affecting high, low, or all
frequencies - Distorted sound (like “blown”
loudspeaker) - Ear fullness or pressure
- Ear feels numb or blocked
- May be associated with ear pain
- May also have Tinnitus or Vertigo
T/F Remove impacted cerumen prior to
making a Dx of hearing loss
T
Conductive hearing loss structures
- Involves auditory canal, tympanic membrane, & the ossicles
- Lesions in the auricle, external auditory canal, or middle ear
can cause conductive hearing loss - Often reversible
Sensorineural hearing loss structures
- Involves cochlea and CN VIII
- Often permanent
Weber test
- A 256 or 512 Hz tuning fork is placed on the mid forehead
- Sound should be perceived equally bilaterally
- Lateralization of sound = + test
Rinne test
- Place the tuning fork against the mastoid process & count
- When the patient no longer hears the sound, note the number of seconds & rapidly
reposition the tuning fork 1-2 cm from the auditory canal, & count - The patient should indicate when sound is no longer heard
Review weber/rinne results
:)
Audiometry
- Most widely accepted diagnostic test for
hearing loss or concerns - Usually obtained in a sound-proof
environment - Demonstrates how loud sounds need to be at
different frequencies for you to hear them - “Audible threshold”
Most widely accepted diagnostic test for hearing loss or concerns
Audiometry
Tympanometry
Graph
* Relationship between air pressure in the canal and movement of
the tympanic membrane (TM)
* Provides volume measurement and pressure measurement