Hearing Loss Flashcards
(27 cards)
Different categories of hearing loss
- Conductive
- Sensorineural
- Mixed
The 2 tuning fork tests to help distinguish a conductive from a sensorineural hearing loss
Rinne & Weber
How is the Rinne test performed?
- Strike prongs of fork & place it on mastoid process behind ear
- Ask can they hear the fork
- If vibrations are inaudible, suggests sensorineural hearing loss
- If vibrations are audible, ask patient to let you know when they can no longer hear the sound
Which should be better - air conduction or bone conduction?
Air conduction
Frequency of tuning fork for Rinne & Weber tests
512 Hz
What is a Rinne positive result?
Normal - can still hear the sound when held near the ear
What is a Rinne negative result?
When they cannot hear the sound when held near the ear - suggests that air conduction is abnormal (conductive hearing loss?)
How is the Weber test performed?
- Apply fork to hear in midline of forehead & ask where the sound is loudest - midline or one ear in particular
- The tone is heard centrally with normal hearing
Patient complains of left-sided hearing loss & sound lateralises to left - what does this indicate?
Conductive hearing loss - sound being conducted through bones of skull to inner ear
Patient complains of left-sided hearing loss & sound lateralises to right - what does this indicate?
Left-sided sensorineural hearing loss - auditory nerve not conducting impulses regardless of where sound is coming from
Factors that impair hearing
- Age
- Noise-induced hearing loss
- Trauma/injury to head or ear
- Ototoxic drugs (e.g. gentamicin) & chemicals
Genetic conditions e.g. Meniere’s disease, otosclerosis - Infections e.g. otitis externa (Swimmer’s ear), otitis media, mastoiditis
- Autoimmune diseases e.g. MS
- Obstruction e.g. wax, foreign body
- Ear conditions e.g. acoustic neuroma, cholesteatoma, perforated eardrum
Different types of tests in an audiometry exam
- Tuning fork tests (Rinne & Weber) - distinguish type of hearing loss
- Pure tone testing (audiogram) - minimum volume required to hear each tone is graphed
- Speech audiometry
- Immittance audiometry - function of eardrum & flow of sound through middle ear
- Tympanometry - vibration of eardrum & middle ear pressure
What does a steady line connecting threshold levels at top of audiogram indicate?
Normal hearing
What trend on an audiogram is common in age-related hearing loss?
A line that slopes downward for higher frequencies
Term for age-related hearing loss
Presbycusis
Characteristics of age-related hearing loss
- Reduced hearing sensitivity & speech understanding in noisy environment
- Slowed central processing of acoustic environments
- High tone hearing loss
Why does age-related hearing loss happen?
Could be genetic or due to changes in inner ear & cochlear nerve - gradual
How does noise induce hearing loss?
With excessive shearing force of stereocilia, this can lead to cellular metabolic overload, cell damage & death of hair cells in Organ of Corti
What is noise-induced hearing loss?
Sensorineural hearing impairment that begins at higher frequencies due to chronic exposure to excessive sound levels
Psychological effects of hearing impairment
Anxiety, frustration, embarrassment, shame, sadness
Psychosocial effects of hearing loss
Affects communication, occupation, social interactions, quality of life
What is tinnitus?
The perception of sound that does not have an external source, so other people cannot hear it
Some causes of tinnitus
ARHL, NIHL, build-up of earwax, otitis media, Meniere’s disease, certain medications, head or neck injuries, acoustic neuroma
Treatment strategies for hearing impairment
- Removal of earwax
- Surgery
- Hearing aids
- Cochlear implant
