Physiological methods in audiology Flashcards
Name 3 types of physiological testing.
- ABR (auditory brainstem response)
- ASSR (auditory steady state response)
- OAE (otoacoustic emissions)
What are OAEs measuring?
The OHCs
Can OAEs be measuring if the 8th cranial nerve has been severed?
Yes
Can OAEs be measuring if there is a middle ear pathology?
No
When we get a pass result for OAEs, this indicates that the ______ and the _____ are functioning properly.
Middle ear and OHCs
Name the four types of OAEs
- SOAES (spontaneous)
- SFOAES (stimulus-frequency)
- TEAOE (transient-evoked)
- DPOAE (distortion-product)
Why don’t we use SOAES in clinic?
Because they are only able to measure up to 30 dB, which means they cannot identify hearing loss.
Name the two types of OAEs that are used in clinic?
- TEOAE
- DPOAE
Which OAE is used for hearing screenings? Why?
TEOAE, because they can detect hearing loss starting at 30-50 dB
Name 3 differences between TEOOAE and DPOAE
- TEOAE is quicker, DPOAE is slower
- TEOAE needs quiet, DPOAE can have a noisy environment
- TEOAE is most sensitive up to 2kHz where DPOAE is most sensitive above 4kHz
What is the difference between ABR and ASSR?
ABR is better for neurodiagnostics and ASSR is better for threshold search because ABR can only go up to 80 dB HL and ASSR can go up to 120 dB HL, so ASSR can detect more profound losses.
When would we refer someone to do an ABR? Name at least 5 examples.
- Asymmetrical hearing loss
- Unilateral tinnitus
- Vertigo
- Sudden hearing loss
- People who have a poor WRS with normal/mild thresholds
What are the 4 kinds of ABR?
- Short latency
- Middle latency
- Long latency
- Event related potentials
What area does short-latency ABR measure? Which waves are involved?
It measures the hindbrain, and uses the waves I, II, III, IV, V and V being most important
What area does middle-latency ABR measure? Which waves are involved?
It measures the midbrain, and uses Pa, Pb, Na, Nb
What area does long-latency ABR measure? Which waves are involved
Forebrain, and waves P1, N1, P2, N2
What wave is used for event-related potentials?
P3 or P300
Name 5 parameters important for ABR
- Latency
- Interlatency
- Amplitude
- Morphology
- Reproductibility
How many electrodes are used for ABR? Whats the name of the most important electrode?
4.
The ground
What filters are used for adult ABR and child ABR?
Adult: 100-3000 Hz
Child: 30 Hz
What is the benefit of using a two channel ABR?
When using two channels we are able to measure ipsi and contra
Name 4 things that can impact/interfere with ABR results.
- Age
- Sex
- Medication
- Temperature
Which ABR wave is most amplified for newborns?
Wave I
Is latency longer for adults or for children?
Children
How sensitive is ABR to retrocochlear disorders?
95%
Name the four disorders that are commonly seen on ABR
- Acoustic neuroma
- Multiple sclerosis
- Parkinsons
- ANSD
Which ear is abnormal and why?
The left ear because a normal ear would have an SNR of at least 6 dB or higher
Name the two types of stimuli used for ABR
- Click
- Tone-burst
Name at least 5 things we can see in an abnormal ABR
- Poor reproductibility
- Poor morphology
- Increased latency
- Reduced amplitude (esp. wave V)
- Increased interlatencies
What is P300? what does it involve?
At P3 or P300, a patient can have a response to a stimuli that causes this wave to peak.
We use the odd-ball procedure where we use a frequent signal and a rare signal.
