AC Hearing aids

Question 1

Who is a candidate for hearing aids?

Answer 1

Anyone with a hearing loss that is impacting communication and/or daily activities.

Question 2

Patient Centered Orientation

Answer 2

“Providing care that is respectful of and responsive to individual patient preferences, needs and values, and ensuring that patient values guide all clinical decisions”

Needs of each patient may be different
Don’t have to start with a blank slate for every patient
Audiologist is expert on hearing loss/hearing aids, but patient is an expert on their life and experience with hearing loss
Encourage open dialog
Top-down and Bottom up

Question 3

What makes a good hearing aid candidate?

Answer 3

Someone who is motivated
Someone who needs help
A person with good word recognition
Useable hearing that can be aided
Limitations on profound hearing losses
Poor word recognition
Difficulties only under adverse listening conditions

Question 4

Listening Devices and Related Technology

Answer 4

Assistive Listening Devices
Hearing Assistive Technology Systems (HATS)
Goals (of the technology):
Make speech audible
Restore range of loudness
Augment communication through nonauditory means
Enhance personal safety and environmental awareness

Usually used in conjunction with HAs

Question 5

Hearing aids: Major trends

Answer 5

Miniaturization
Enhanced signal processing
Different kinds of signal processing and microphones
Noise reduction
A radio link connection between the left and right HA
Wireless technology
Smartphone interfacing

Question 6

Hearing aid styles

Answer 6

Air conduction hearing aids
Bone conduction hearing aids
Used when patient’s can’t wear traditional amplification
Uses bone conduction

Implants

Question 7

Digital Hearing aid components

Answer 7

Digital signal processing
Acoustic signal is converted to binary numbers and processed using algorithms
3 Main parts of a hearing aid
Microphone: picks up the acoustic signal -Converts it to an electrical signal
Amplifier: makes sound louder among other things
Receiver (speaker): Converts the processed electrical signal back to acoustic signal and passes it on to your ear

Question 8

five key components

Answer 8

Microphone
Microchip
Amplifier
Battery
Reciever

Question 9

Batteries

Answer 9

Batteries
Last for a few days to a few weeks
Disposable and rechargeable (newer)
Sizes: 10, 312, 13, 675

Question 10

Microphones

Answer 10

Omnidirectional vs directional
Directional mics: enhance signal to noise ratio
Automatic directional systems: switch on their own based on environment
Improvement in hearing in background noise

Question 11

Omnidirectional

Answer 11

As mentioned above, this microphone type has no directionality. “Omni” mics are used to pick up all or wide range audio. For example, they are used for choirs, when many instruments are played at once, or to pick up all audio on the stage.

Omnidirectional
All around you

Question 12

Microphone directionality

Answer 12

Microphones have directionality that indicates from which direction they best pick up sound. Microphones that do not have any specific directionality (called “omnidirectional” microphones) will pick up sounds from all directions, thus sounds other than those of the intended instruments will go into the microphone. Particularly with PA systems, many instruments will often be played together on a stage, so it is necessary to have a good understanding of directionality. Some microphones have switches to select the preferred directional pattern.

Question 13

Unidirectional

Answer 13

This type of microphone features directionality to the front only and is also known as “cardioid” (because of its heart shaped directional pattern). Cardioid mics are most often used with PA systems for vocals, instruments, etc. In the diagram, 0°indicates the front of the microphone.

Question 14

Directional

Answer 14

Directional
Only in front of you, perceiving the things directly in front of you
Biggest jump in improvement over the last twenty years has been in Microphones
Used to have omnidirectional microphones – 360 degree microphones
Directional microphones – two microphones, they can figure out by timing and intensity differences what sound is coming from the front and the back
For directionality purposes you need to have the space to put two microphones

Question 15

Bidirectional

Answer 15

This type of microphone features directionality to the front and rear. Because bidirectional microphones will also pick up audio to the rear, they are rarely used with PA systems. They are often used to record audio between two people who are face to face, such as during radio interviews.

Question 16

Amplifier

Answer 16

Gain: Amount of amplification provided

Noise reduction

Wind reduction

Wide dynamic range compression

Question 17

Peak-clipping

Answer 17

A DISTORTION caused when the GAIN of an amplifier is increased to a point where the high points, orpeaks, of the SIGNAL or WAVEFORM are cut off at a level where the amplifying circuits are driven beyond their overload point.
Gain saturates at a certain level
Peak-clips which limits level of audio signal
Introduces distortion

Question 18

Compression

Answer 18

Goals:
Limit the maximum output of hearing aid so patient is never uncomfortable
Provide a range of sounds within a persons dynamic range (soft, average, loud sounds)
Provide a varying amount of gain as a function of the input level (if someone is whispering add more gain, if sound is too loud compress)
May be linear up until a certain point (kneepoint) then change into compression
Kneepoint (point where linear amplification changes to compression)
Attack and release times

Question 19

Receivers

Answer 19

Creates an enhanced soundwave.
Convert the signal sent from the processor to audible acoustic sounds.
It is placed directly in the ear canal or connect to a small tube that’s inserted into the ear.

Question 20

Other features

Answer 20

ON/OFF
Typically just battery door open vs battery door closed
May be an on/off switch
May be on VC wheel

Question 21

Telecoil

Answer 21

Induction coil within hearing aid
Used for telephone (land lines) or public loop systems
Electromagnetic: bypasses HA microphone
Not on all hearing aids
Minimize feedback
Can be automatic t-coil on some newer HA’s

Question 22

Volume Control

Answer 22

User can adjust level of amplification
Can be a wheel, a toggle switch, or done on a remote or smart phone
Audiologist can disable this feature or limit the range

Question 23

Program button

Answer 23

Multiple memories
Customize programs
Small button on hearing aid
Can be disabled/enabled by audiologist on the software

Question 24

Remote Control

Answer 24

Can change programs
Change volume

Question 25

Hearing assistive technology: Accessories

Answer 25

Remote microphones
Roger
FM
TV Links
BLUE TOOTH STREAMERS!!!!!

Question 26

Audiologist’s Favorite Feature

Answer 26

DATALOGGING!!!!!
Can show use time, environments, program use, VC use, volume levels, etc.

Question 27

Frequency Compression

Answer 27

Compresses high frequencies in hopes of improving detection of high frequency consonants

Question 28

Earmolds

Answer 28

Some HA’s use earmolds from silicon or acrylic material
Deliver sound to the ear and may hold hearing aid in place
Custom-made

Soft silicon material
Most of the time it doesn’t have any technology in it
If you don’t have a good seal the sound will leak out and get reamplified by the microphone making a squealing noise

Pic on right utilizes a dome
Not custom

Question 29

Hearing aid Styles

Answer 29

CROS or BiCROS
Used when there’s only one “hearing ear”
Can be used with 1 normal hearing ear or an ear with any degree of hearing loss

CROS When your better ear hears normally (CROS)
The transmitter placed behind or inside your poorer ear, picks up sound and transmits it wirelessly to the normal hearing ear. The hearing in your good ear will remain natural and completely unaffected.
ted States)
÷ Notes
BiCROS When you have a hearing loss in your better
ear (BiCROS)
The transmitter placed behind or inside your poorer ear, picks up sound and transmits it wirelessly to the better hearing ear. At the same time, the receiving hearing aid also serves as an amplifier improving hearing in that ear.

Question 30

Hearing aid Styles

Answer 30

Behind the ear (BTE)
Mild to profound hearing losses
Earmolds or open fits
Most flexible type of amplification
Safety and comfort
Less feedback
Fewer repairs
Easy to clean/maintain

Question 31

Receiver in Ear/Canal (RIC, RIE)

Answer 31

Most popular style right now!
Comfortable
Cosmetically appealing
May be difficult for some older adults
Anything that completely fills up the canal a patient with normal low frequencies will hate
It will distort what they are hearing

Question 32

ITE AND ITC

Answer 32

IN-the-ear and In-the-canal
Custom
ITE fills concha, ITC does not
All components are housed in your ear
Advantages: microphone placement, easier insertion and removal
Disadvantages:
Degree of hearing loss
Harder to clean and cerumen issues
Occlusion affect
Harder to maintain and fix

Question 33

IIC/CIC

Answer 33

Completely in canal
Pinna effect
Small
Not many options available
No directional mics, no buttons, etc
Difficulty removing them, subject to cerumen buildup
Maximize Pinna Effect
Localize up and down in elevation
CIC’s
Nothing is occluding the pinna

Question 34

Hearing aid styles

Answer 34

CROS or BiCROS
Used when there’s only one “hearing ear”
Can be used with 1 normal hearing ear or an ear with any degree of hearing loss
CROS – Contralater Routing of Signal
For patients that have a unilateral HL and shift to the good hearing ear
BiCROS
Does same thing, but takes the sound from the HL ear but shifts it to the better ear but even that ear is not perfect and will need further amplification

Question 35

HA Selection

Answer 35

Cognitive abilities

Dexterity

Price

Degree of hearing loss
Ex profound HL- no CIC
User preference
If patient won’t wear it, it’s not the best choice
Something is better than nothing
Costs
Levels of technology
Lifestyle
Ex physician uses stethoscope
Person who works in noise, etc
Physical Status
Ear infections/draining ears
Frequent cerumen build up
Malformed ears

Question 36

Hearing aid orientation

Answer 36

Provided at fitting and subsequent visits
Function of hearing aids
Insertion/removal
Maintenance and cleaning procedures
Batteries use and disposal
Telephone use
Realistic Expectations
Troubleshoot
Warranty information
Printed info about hearing aid

Question 37

Programming

Answer 37

The National Acoustic Laboratories (NAL) procedures and the Desired Sensation Level (DSL) procedures have been used widely to prescribe hearing aid gain.
+Proprietary software- Each hearing aid manufacture has its software
The different procedures are based on different principles and formulae.
The target gain-frequency responses for many hearing losses differ markedly between prescriptions

Question 38

Verification

Answer 38

Real-ear measurements
Gold standard
Conducted in order to verify correct programing
Only ~30% of healthcare professionals do it
Speech mapping

Question 39

Validation

Answer 39

Validation  is the patient receiving benefit from the HA

Ensure patient’s hearing related disability has been improved
Speech testing with and without hearing aids
Questionnaire or Inventory
Benefit: change in hearing related disability from amplification use
Satisfaction: overview of physical, social, psychological and financial changes as a result of amplification

Question 40

Validation (cont)

Answer 40

Use Time
Residual activity limitations
Residual participation restrictions
Impact on others
Quality of life