Audiological Management Flashcards
What is a CROS hearing aid?
Contralateral routing of signals.
Used with those with unilateral hearing losses where any sound coming from the dead ear will be sent over to the hearing ear
When would we resort to a BAHA?
When traditional hearing aids are not possible (ex. Middle ear pathologies that are permanent or external ear pathologies)
What are the four types of custom hearing aids?
ITE (in the ear)
ITC (in the canal)
CIC (completely in canal)
IIC (invisible in the ear)
When selecting a hearing aid, what are things we need to consider?
- Type of hearing loss
- Degree of hearing loss
- Personal limitations: ex. Dexterity, vision impairment, etc.
- Comfort/personal preference
- Type of dome or mold
What is the difference between CROS and BICROS?
CROS = one ear is normal hearing and the other has non functional hearing
BICROS = the better ear has some hearing loss and the other has non functional hearing
Explain binaural vs monaural
Monaural is hearing with one ear, binaural is hearing with two ears.
Binaural is always better because :
- Improves localization
- Binaural summation
- Better SNR
What is the importance of real ear measurements?
To evaluate how the hearing aid is working in regards to the patients hearing loss
What is REUR/REUG?
REUR = real ear unaided response
REUG = real ear unaided gain
- It is how much the ear can amplify without the hearing aid.
What is REAR?
Real ear aided response.
- This is the response when the hearing aid is turned on and amplified in the clients ear.
What is RECD?
Real ear to coupler difference
- It is used to see the difference between a real ear and a 2cc coupler
What is OSPL90, or MPO?
It is the maximum level the hearing aid can reach in terms of volume
What is the formula for insertion gain?
REAR - REUR
It is the difference between how much volume the hearing aid is providing with how much volume the ear is without the hearing aid.
What is attack time for hearing aids?
It is a response to a sudden change in volume levels.
Attack time reduces gain in response to a sudden increase (ex. Door slamming)
What is a release time for hearing aids?
It is a response to a sudden change in volume levels.
Release times is when there is a delay before gain returns to the original. (Ex. Door slams, attack time kicks in, goes back to normal = release time)
What is full on gain?
The amount of gain provided by the HA when the volume is at the highest level
What is the frequency response curve for HAs?
The frequency response at 55, 65, and 75 dB SPL across speech frequencies of the HA
What is the difference between compression and expansion?
- Compression = type of automatic gain control where there is a smaller increase in output
- Expansion = type of automatic gain control that reduces amplification for very soft sounds such as ventilators for example.
What is peak-clipping?
When the hearing aid reaches a certain level where the hearing aid cannot produce a louder signal, it results in peak clipping, which can make sounds distorted
What are three benefits of compression in hearing aids?
- Soft sounds are audible
- Moderate sounds are comfortable
- Intense sounds are loud but not uncomfortable
What is the ideal compression ratio and why?
Anything under a 3.0, because it improves audibility of softer sounds and speech
When would we use NAL-NL2 VS NAL-NL1?
NAL-NL2 is the standard to make speech intelligible and overall loudness comfortable but NAL-NL1 is a louder more powerful prescription that is good for those who want to hear better and louder in general
What is the one main issue with WDRC? What is one solution?
It amplifies soft sounds such as the fridge, floors, etc.
- It allows soft sounds to be heard in an audible range and can be overwhelming to the auditory system.
One solution is expansion which helps silent the hearing aid for those sounds like a noise reduction.
What are the three types of domes and who are they used for?
- Open domes = used for good low-frequency hearing to allow for natural hearing and more ventilation.
- Vented/closed domes = used for more significant losses, allows for more gain
- power domes = used for the most significant losses, helps to eliminate feedback,
Name the four components of a hearing aid
- Microphone
- Amplifier
- Receiver
- Battery
What are the main differences between ITE/ITC and CIC/IIC?
- Directional microphones (ITE/ITC)
- Bluetooth connectivity (ITE/ITC)
- Longer battery life (ITE/ITC)
- Almost invisible (CIC/IIC)
What is the most popular type of hearing aid and why?
RIC/RITE (receiver in the canal or receiver in the ear).
COMFORT! These are the most comfortable hearing aids compared to customs.
They have a longer lifespan and better reliability (Bluetooth)
The patient says; there is an echo in my voice, my voice is too loud. What is the problem? What are the solutions?
Occlusion.
Switch to a more ventilated ear piece or increase size of vent on the mold
The patient says that they hear whistling coming from the hearing aid, what is the problem? What is the solution?
Feedback.
1. Check for wax
2. Make sure hearing aid is fitting properly
3. Make sure gain is not exceeding MPO
4. Reduce venting if possible
5. Re-run feedback test
6. Decrease HF gain >3kHz
Patient reports that peoples voices sound robotic or artificial? What do you do?
Decrease HF gain >3kHz by 2 steps and decrease CR (increase MPO)
Patient reports that all sounds are too loud, what do you do?
Lower all gain by 2 steps
Patient reports they aren’t able to hear soft sounds well, or people are mumbling. What do you do?
Increase g50 by 2 steps
Patient says they hear too much ambient noise, like fridge running, ACs, etc. What do you do?
Lower g50 <1kHz by 2 steps
Patient reports they feel like speech is unclear, what do you do?
ALWAYS check what the WRS was and make link between the results.
Increase HF gain >3kHz by 2 steps
Patient reports the sh and s sounds are too harsh and tinny, what do you do?
Enable frequency lowering and decrease HF gain by 2 steps
Patient reports they cannot hear well in noisy environments, what do you do?
Compare QSIN and WRS results first !!!
Add noise program or speech in noise program
Patient reports they cannot hear well in noisy environments, what do you do?
Compare QSIN and WRS results first !!!
Add noise program or speech in noise program
