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Amplification > Final 712 > Flashcards

Final 712 Flashcards

1
Q

What does a test box measure?

A

The performance of a hearing device in a controlled simulated environment

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2
Q

When are test box measures done? (4)

A

Before the hearing aid leaves the manufacturer
Before fitting a device in the clinic
Troubleshooting a patient complaint
After a hearing aid has been returned from a manufacturer repair

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3
Q

What can a test box do? (3)

A

Produces sounds of specific SPL
Attenuates ambient noise
Minimizes reflected sounds reaching the HA

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4
Q

What are the two HA couplers and what type of HA’s use each?

A

HA1 uses customs and RICs
HA2 is only for BTEs

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5
Q

When do we use putty?

A

Helps to seal sound in to make sure measurements of the HA is accurate is EAA
Usually used with customs because they are not standardized (it would cover the sound bore and vent)

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6
Q

Basic test box procedure

A
  1. couple the HA to the test box (ensure it is oriented the correct way, the front mic should be facing the front speaker)
  2. Paly specific types of measurement signals through the test box speakers (pure tone, broadband, speech)
  3. record the HA response to the signals
  4. compare the final measurement to a standard
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7
Q

Which ANSI standard defines HA performance?

A

ANSI S3

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8
Q

Why do we use ANSI standards?

A

Used as a quality check to determine HA performance
Provides equal ground with which to tell all HA (standardized measurement)

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9
Q

What is IEC?

A

International electrotechnical commission
Europe’s equivalent to ANSI

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10
Q

Full on Gain (FOG)

A

Gain control of HA is set to maximum output, this will generate a curve

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11
Q

High frequency average (HFA)

A

Average gain or SPL in decibels at 1000, 1600 and 2500

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12
Q

OSPL 90 curve

A

Reflects how the HA responds to a 90 dB SPL input when the HA is set to max gain
OSPL is the maximum output level if the hearing aid measured with a 90 dB SPL input signal (how loud is the HA capable of being)

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13
Q

Why is 90 dB used for the OSPL 90 curve?

A

Nearly always enough to saturate the HA

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14
Q

Reference test gain

A

HFA gain for an input of 60 dB when set to reference test position

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15
Q

Acoustic gain

A

At each frequency, the result obtained by subtracting the input SPL from the SPL coupler
What went in compared to what went out
This will have two gain values

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16
Q

Attack time

A

Time between the abrupt increase from 55 to 90 dB SPL and the point where the levels have stabilized within 3 dB of the steady state value for 90 dB input
How quickly does compression start after the onset of a loud sound

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17
Q

Equivalent input noise level (EIN)

A

Measurement of the internal noise (comparison between no sound and 50 dB input)

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18
Q

Reference test setting of the gain control (RTS)

A

Reduces volume to a position that will not saturate the hearing for mid-level input signals
Battery drain is measured at RTS

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19
Q

EAA steps with verifit 2

A

Calibrate, position HA in test box with correct coupler, connect HA to manufacturer software and begin test settings, FOG, RTS/gain, return HA to user settings, analyze measurements according to published spec sheet and ANSI tolerances

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20
Q

How do you calibrate the test box?

A

Under the test box test options, select calibration
No couplers are attached during this

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21
Q

Why do we need to calibrate?

A

Need to make sure that all measurements run in the test box are standardized and can be compared to each other and ensures that equipment is working

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22
Q

Positioning the HA in the test box with the correct coupler

A

EAA is always completed using blue coupler set
TRIC adapter attaches to HA1 coupler, otherwise would have to use putty- receiver should be pulled through but maintaining a tight seal
HA is centered over the “x” with front mic of the HA facing the front test box speaker
Reference mic is bent around to point at the front mic of HA
All HA run on the blue left coupler mic

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23
Q

How to run FOG?

A

Connect HA to manufacturer software using correct programming device and locate “test settings”
Some software do not have test settings, requiring the audiologist to put the HA into FOG and RTS manually (turn off all automatic features like feedback and noise management then max out programming bands for FOG, adjust gain down for RTS
On the verifit, under test box tests can select ANSI/IEC and follow directions

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24
Q

How to run RTS/gain?

A

Once FOG measurements are complete a green triangle will appear with the directions to “set VC to RTS”
The triangle with all but disappear once the HA has been programmed correctly

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25
Q

EAA with verifit 1

A
  1. test box measures
  2. HA1 coupler (RICs and customs require putty and attach to HA1 coupler, sound bore should be as close to the entrance of the coupler as possible, all couplers are silver)
  3. positioning (verifit 1 speakers are labeled left and right instead of front and back so have to orient HA mic to face the left speaker)
  4. attack and release (attack and release are rarely measures any more, seen in verifit 1 AGC seen, best to run attack/release with compression settings at maximum)
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26
Q

What are the differences between EAA with verifit 1 compared to 2?

A

Screen interface, but the list of options are mostly the same
Only 1 set of couplers for 1
Positioning in the test box is at an angle instead of front and back speakers
Additional test measurements require no change of position or equipment while verifit 2 does

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27
Q

What does it mean when a HA has no “test settings”?

A

Need to place HA in FOG and RTS manually using the programming bands
Turn off as many automatic features as possible (feedback, whistle block, noise suppression, frequency lowering)
FOG (max out all gain and MPO settings)
RTS (reduce programming band until green triangle disappears)

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28
Q

Measurement tolerances

A

Max OSPL 90- plus/minus 3
HFA OSPL 90- plus/minus 4
HFA FOG- plus/minus 5
RTG- HCC uses plus/minus 2
Total harmonic distortion- 3%
EIN- HCC uses less than 30

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29
Q

What do you do if the HA fails EAA?

A

Check coupling and placement in the test box
Can any part of the HA be repaired in the office? (may be able to replace the receiver for a RIC, an earhook for a BTE and clean the mic/wax traps for a custom
Once you have ruled out other causes of failure you will need to send the HA to the manufacturer for repair because internal electronic parts can only be replaced by the manufacturer

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30
Q

Why may you not complete EAA?

A

Trust in the manufacturer- companies often include test box runs with many of the repair invoices
Time
Uncertainty of the test procedures
Cost of test equipment

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31
Q

What are three questions that can be asked about EAA?

A

Is EAA warranted?
Is EAA efficient?
Is EAA cost effective?

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32
Q

Cost/benefit of EAA

A

HA with faulty electronics can often fly under the radar for a while
Having an objective way to test a HA takes all the guesswork out
Lots of repeat troubleshooting appointments waste time and money
Fitting a brand new HA with electronic problems greatly decreases the patient confidence in the whole process
Add value to your practice

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33
Q

When might you use a test box measure?

A

New HA from manufacturer
Repaired aid back from manufacturer
Check for excessive intermodulation distortion
Check for directional microphone response
Patient complaint not resolved by cleaning or simple repairs

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34
Q

Define DSP

A

How the hearing aid converts acoustic sound into digitized codes

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35
Q

Define sampling rate

A

Number of times per second that the hearing aid analyzes incoming sound at regular intervals
This is what differs between tiers

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36
Q

DSP helps make what possible

A

Frequency channels, compression, noise reduction, feedback suppression, directionality of microphones

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37
Q

Advantages of DSP

A

No noise in the digital conversion process
Sound can be modified with simple arithmetic
More flexibility
Better customization

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38
Q

What is the disadvantages of DSP?

A

Increased battery consumption

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39
Q

What are the two primary concepts involving DSP and what is the difference?

A

Sampling is about time information
Binary code/bits is about amplitude information

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40
Q

How does DSP work?

A

Acoustic signal is filtered through the analog anti-aliasing dilter and picked up by A/D converter
Acoustic signal is sampled periodically
Samples are converted to numbers via the electrical signal
Processing takes place through mathematical calculations to manipulate the digitized output
The numbers/digitized output is converted back to an acoustic signal

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41
Q

Sampling

A

This is how the A/D converter measures the signal amplitude at discrete points in time
The number of times per second a signal is sampled
If this is too low, information will be lost and a very low rate may add information that was not in the original waveform

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42
Q

Nyquist-Shannon theory

A

Sampling rate must be two times the highest frequency (Nyquist frequency) of the incoming signal

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43
Q

Aliasing

A

This is when false frequencies are represented and there is an incorrect processing of the signal
More low frequencies will be included then what was in. the input due to a low sampling rate
To find the aliased signal frequency = signal - sampling rate

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44
Q

Anti-aliasing filter

A

Placed before the analog-digital converter, input passes through a low pass filter
Frequencies above half the sampling rate are removed

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45
Q

Over-sampling

A

The sampling rate is at a frequency that is more than twice the Nyquist
Advantages- increases dynamic range and reduced noise
Disadvantages- greater power consumption and delays

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46
Q

Bits

A

The greater number of bits will result in better digital approximation of the signal
Too few bits may result in a rounding of the signal which equals noise (quantization error)

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47
Q

Quantization error

A

Difference between the actual analog signal and the digital representation resulting from rounding off numbers
In HA, this may be random noise, harmonic distortion and high frequency splatter
To avoid this use a higher bit rate

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48
Q

Quantization

A

Process of mapping input values in smaller set, often with a finite number of elements
Assigning binary values to analog signal
This is what gives a representation of an analog signal

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49
Q

Digital-to-digital converter

A

Takes many bits for a specified sample and changes it to a series of single bits
This has a higher sampling rare than an analog to digital converter
Smooths the output waveform for the receiver to process the voltage back into an acoustic signal
This is part of the digital-to-analog converter
A DAC may smooth by removing harmonics above the Nyquist

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50
Q

Two types of converters

A

Traditional- usually use the minimum sampling frequency which reduces power consumption
Modern- allows for improved dynamic range and increased frequency response

51
Q

Overview of the fitting process

A

Testing
Communication/lifestyle assessment
HA selection
HA fitting
Verification
Patient orientation
Follow up appointment and validation

52
Q

Is your fitting effective?

A

Provided audibility of speech and environmental sounds
Not over-amplified sounds to the point of patient discomfort
Tailored the programming according to the patients age, listening experience, length of auditory deprivation, loudness tolerance

53
Q

Verification methods

A

Soundfield measures (functional gain/aided audiogram, aided speech testing)- subjective
Real ear measures- objective
Test box/coupler measures- objective
Asking the patient (subjective)

54
Q

Functional gain- aided audiogram

A

An attempt to verify the response of the hearing aid in a frequency specific fashion
Most common form of verification
Will show up on an audio as an A
Limitation of this is that it is aided so it is the absolute threshold when gain is in place
Difference measure between soundfield thresholds in the aided and unaided condition
Want aided thresholds to be as normal as possible

55
Q

How is functional gain of an aided audio measured?

A

Obtain soundfield threshold in a booth at the frequencies of interest without HA in place
500, 1000, 2000, 3000, 4000, maybe 6000
Obtain sound field measures in identical environment with HA in place and active and use a warble tone as it is better than pure

56
Q

Benefits of functional gain aided audio

A

Involves the entire auditory system
Relies on behavioral responses
Intuitive for patients to understand
Easy to administer for clinician
Cheap- no special equipment
Only option for CI, ME implants and BAHA

57
Q

Limitations of functional gain aided audio

A

Typically only performed at one input level
Frequency/amplitude resolution is fairly broad compared to probe-microphone measures
Aided thresholds are often invalid for normal and near normal thresholds
Aided thresholds are often binaural (will not be able to tell which ear is responding unless masking is present)

58
Q

Differences between amplification and gain

A

Amplification- sound was made louder
Gain- a comparison of the input versus the output; difference between what comes in and what went out

59
Q

Aided speech testing

A

Complete speech discrimination testing with the hearing aids in place using a soundfield speaker
Can also compare a speech measurement in the unaided condition to an aided condition (recommended using soft or conversational speech levels)
Aided speech testing is very intuitive for the patient

60
Q

Overview of a proper fitting

A

Calibrate verification system
Otoscopy and probe mic placement
HA placed over probe mic (inside the ear)
Select prescriptive formula/rationale on verification system
Run specific types of stimuli and record what the HA is doing in the ear
Adjust gain in the manufacturer software
Re-run stimuli and keep adjusting until the targets are met

61
Q

Real ear measures

A

Measuring sound rom inside the ear canal
Requires a probe mic at the level of the eardrum
Provide accurate, real-time response of sound in the ear
Frequency and gain specific with good resolution

62
Q

Types of real ear measures

A

Response- a measure of absolute SPL in the ear canal
Gain- a difference/comparison measure (an output response expressed relative to the input signal or a reference response)

63
Q

Real ear aided response (REAR)

A

Measuring sound from inside the ear canal with the hearing aid in the ear and turned on

64
Q

Real ear aided gain (REAG)

A

REAR minus the input signal as measured at the reference mic; difference between an aided sound measured in the ear canal versus a sound measured at the reference mic

65
Q

REIG

A

SLP at eardrum when aided minus SPL at eardrum when unaided
Takes into account natural amplification from the ear canal
Involves measuring the REAG and REUG, or REAR and REUR

66
Q

Why do probe tubes need to be calibrated?

A

The tubes resonate and since they have their own resonance properties it needs to be taken into account

67
Q

Visually assisted positioning

A

Use otoscope to check depth
Probe tube should be 4-6mm from the TM

68
Q

Acoustically assisted positioning

A

Use REUG measures on the verification system to monitor placement
This is a more advanced technique where you need to know the normal resonance values

69
Q

Average length method

A

Move collar to average length based on gender and age
28-30 for males, 26-28 for females, 20-25 for children

70
Q

Geometric positioning

A

Measure alongside earmold/dome and add 5mm, move collar to match, and insert probe until the marker is at the inter-tragal notch

71
Q

Bump and pull

A

extend the probe tube into the ear gently and slowly until the end touches the erdrum and then back it up slightly

72
Q

Audioscan probe guide

A

Once the probe mic has been placed, can cross check the depth using an automated guide within the Verifit 2

73
Q

What happens when the probe tube is not deep enough?

A

As the tube gets farther from the TM, will get weird standing waves and will impact high frequencies

74
Q

Real ear unaided gain (REUG)

A

The difference between a sound measured in the unoccluded ear canal versus the sound measured at the reference mic

75
Q

What is RECD?

A

Real ear dial difference
Correction factor for ear canal resonance
Difference between the intensity setting in HL on the audiometer dial and the output in the ear canal
Very common in pediatrics and sometimes for adults
RETSPL + RECD - REDD
Get a threshold in HL, need to convert this to SPL so use the RETSPL conversion then use a 2-cc coupler for the RECD conversion then you will have dB SPL in the ear canal
2-cc coupler was created to mimic the resonance of an empty ear canal, so that the hearing aid fitting could be stimulated in the test box
Usually a positive number- the output of the true ear canal is greater than the output of the coupler (the smaller the ear canal the larger the RECD)
RECD measured with foam tip is not the same as RECD measured with an earmold (earmold tubing is longer resulting in high frequency roll off)

76
Q

Speechmapping

A

Verifit automatically converts the dB HL to dB SPL using average REDD
If a measured RECD is not provided, the system also uses an average RECD
Measuring RECDs will recalculate the thresholds and also the associated prescriptive targets

77
Q

How to measure RECD?

A
  1. calibrate the RECD transducer (verifit 1- RECD transducer attached to HA2 coupler; verifit 2- WRECD transducer attached to TRIC adaptor and silver 0.4cc coupler)
  2. on verifit, select the coupling that will be used for the on-ear RECD measurement: either foam tip or earmold (need to use the same coupler from original hearing test)
  3. position patient in front of verifit and place probe tube
  4. attach RECD transducer to foam tip or earmold and place in ear canal over the probe tube (select foam tip that fully expands in ear and fits deeply)
  5. Measure the RECDD/WRECD (two pairs of curves will be generated; top pair will be response of RECD transducer in the coupler (1) and response in the real ear (2), bottom pair is the difference between the upper curves (3) and age-appropriate average for reference (4))
  6. adjust gain in manufacturer software to meet prescriptive targets (verifit will incorporate the RECD and recalculate the displayed thresholds in dB SPL and then recalculate the targets generated from those thresholds)
78
Q

What will happen if there is shallow probe tube placement?

A

Negative high frequency RECD
Rolloff

79
Q

What will happen if the probe tube is blocked or crimped?

A

Significant negative RECD values across the spectrum

80
Q

RECDs with PE tubes/perfs

A

Extra volume will alter the resonance of low frequencies
Negative RECD values because the ME space is being included

81
Q

RECD with verifit 1 versus 2

A

1- uses a 2cc coupler (HA1 for mold and HA2 for BTE), uses old ANSI standards
2- uses 0.4cc coupler, WRECD to reflect expanded bandwidth of modern hearing aids

82
Q

What about open fits?

A

RECDs assume little to no venting (will lose venting if using a test box)
Stimulated REM for an open fit will be inaccurate so use the persons ear to account for loss of the low frequencies

83
Q

Why aren’t RECDs standard for adults?

A

Less likely to be using simulated for adults
Adult ears do not vary as much as children when compared to a 2-cc coupler standard
Some clinicians recommend RECDs to ensure proper correction of the LDLs thresholds during speechmapping not just the pure tone threshold
Remote fitting of devices and pandemic measures would make adult RECDs more useful, as patient contact is limited

84
Q

When not to use RECDs

A

RECD not applied to audiometric thresholds measured with TDH or soundfield
S-REM (simulated REM) with very open venting
For adults, prioritize REAR/speechmapping in all cases if time is limited

85
Q

Stimuli considerations for speechmapping

A

Test stimuli used should be compatible with the hearing aid it is testing
If it is a pure tone: a linear HA should produce similar results to noise signals, applied amount of gain is the same; non-linear HA results may differ depending on the stimulus signal; not recommended for REM as they are very suscpetible to reflections
Speech (excellent for WDRC): most important input signal, interacts with multi-band compressors in a more realistic way than tones, should interact appropriately with signal processing featuring such as feedback management and noise reduction
Broad-band stimuli: may differ greatly in spectrum, amplitude (overall level), bandwidth and spectrum, measurement time windows and other aspects of analysis also affect the results
Narrow-band stimuli: may not be accurate for non-linear HA
Speech-like noise: similar to white noise but includes speech frequencies
International speech test signal (ISTS)
International collegium of rehab audiology (ICRA)

86
Q

International speech test signal (ISTS)

A

Composition of spliced 500ms segments of 6 female talkers
Includes multiple languages- American English, Chinese, French, Arabic, German and Spanish
Put together in such a way to include pauses like real speech, modulation
More acceptable for use internationally

87
Q

International collegium if rehab audiology (ICRA)

A

Provide a selection of speech-like noise signal that could be used as background noise for hearing aid clinical testing and potentially measurement

88
Q

Insertion gain

A

Stimulus dependent and the dependency is specific to each HA
Not recommended to fit a HA with this
Not great for non-linear HA

89
Q

Speechmap measures (verifit)

A

Measures amplification from within the ear canal using recorded speech
Test stimuli include a choice of test signals
Can run stimuli at several different loudness levels
In on-ear mode, the MPO run is a sequence of 85 tone bursts at 1/3 octave frequencies
A variety of prescriptive formula are available and auto-generated

90
Q

Long term average speech spectrum (LTASS)

A

Every speech sample played has own LTASS
Type of REAR (real ear aided response)

91
Q

SII

A

The higher the number the better
Shows what percent of English phonemes are audible

92
Q

Evaluative approach

A

Patient would wear one aid and then compare speech discrimination performance to a second (or third)
Not particularly scientific although hearing aids were also a lot simpler then in terms of features and programming

93
Q

Prescriptive approach

A

A calculation of desired amplification characteristics using a prescription
An early example is the half-gain rule (prescribed gain = half the threshold)

94
Q

Core assumptions of prescriptive strategies

A

Audibility of speech sounds is critical (bandwidth needs to be wide enough to amplify high frequency speech sounds, accounts for degree and configuration of HL)
Amplification for an individual with HL takes place within the constraints of his residual dynamic range

95
Q

Loudness equalization

A

Equalized loudness across frequency bands results in higher speech intelligibility
Goal is to amplify speech sounds so that they are perceived as equally loud
Aims to normalize the perception of overall loudness
NAL: auditory system can only take in so much at once, less about audibility of all sounds, useful for postlingual adults

96
Q

Loudness normalization

A

Assumes restoration of normal loudness perception will create better acceptance by the listener
The goal is to amplify speech sounds so that normal inter-frequency loudness relations are maintained
Low frequency vowels will get more loudness weight than high frequency consonants

97
Q

DSL (desired sensation level)

A

Keep vowels loud
As much audibility as possible
Prescribe amplification such that the entire range of the acoustic signals is placed within the patients dynamic range
Uses loudness normalization
Audibility of speech is most important for learning languages

98
Q

NAL

A

Prescription based on hearing thresholds
Goal is to maximize speech intelligibility while making sure overall loudness of speech at any level is perceived similar to a normal hearing person
Utilizes loudness equalization

99
Q

NAL-NL2

A

Based on new evidence
Make loudness comfortable by carefully allocating gain at frequencies that can make a big contribution to intelligibility
Most common prescription for adults
Loudness model: applied to the amplified speech spectrum and compared to that of a normal hearing individuals loudness perception with the aim of optimizing intelligibility
Intelligibility model: not all frequencies equally important so a weighting is applied, with increased level distortion increases even for those without HL (level distortion), with HL we need louder for audibility but not so loud that we negatively affect intelligibility, as HL severity increases the effect worsens- desensitization (making the sounds louder does not mean better speech understanding for all hearing configurations)
Other factors: gender (females prefer 2 dB less gain), new users (initially prescribed less gain), higher compression ratios, steep losses, unilateral or bilateral fittings (NL2 applies less of a reduction in gain for bilateral fittings and it is level dependent), tonal language

100
Q

Fig 6

A

A fitting formula that can be added to an array of other prescriptive formula
For low input levels, gain is prescribed with the goal of providing aided thresholds of 20 dB
Aided thresholds would then vary for more severe hearing loss
Requires adult patient who can provide a fair amount of feedback

101
Q

Loudness-based procedures

A

Loudness based prescription requires that the clinician create an individualized loudness growth curve for each patient
May be good for people with severe sound sensitivity

102
Q

Why does the verifit make that static noise right before the carrot passage?

A

Equalization process

103
Q

Equalization process

A

The process of controlling the SPL as a function of a frequency at the field reference point
The field reference point is the location of sound inlet of reference mic during equalization
Communicates with the on-ear probe module to figure out how far away the patient is from the speaker
How far away the person is sitting will determine how loud the speech passage is played coming out the speaker
Open fittings (amplified sounds may escape the ear canal and be detected by the reference mic during the equalization process; reference mic thinks the additional sound is from the loudspeaker and the loudspeaker in turn adjusts the speech coming out of the speaker, need to mute HA first)

104
Q

MPO

A

Counsel patients what to expect so they are not startled
Mute opposite ear in the fitting software so that patient is responding to the ear you are measuring

105
Q

Consider ear canal acoustics

A

The response of a hearing aid in a real ear differs fro mthe same hearing aids repsonse in a 2cc-coupler

106
Q

Why is REM so important with open fits?

A

Venting effects cannot be accounted for with RECDs
Venting will change the low frequencies and RECDs will not catch this so need to do REM
Keep in mind, an open fit may also be defined as a dome thats too small for the ear canal, dome may be closed but sound still leaking around it

107
Q

Manufacturer software

A

Represents gain at different frequencies and inputs using estimated values
These numbers have a meaning relative to each other, a larger number means there is more gain at the frequency

108
Q

What percent of audiologists claim that they use NAL or DSL?

A

78%

109
Q

What percent of audiologists use verification?

A

44% but routinely maybe 25%

110
Q

Manufacturer vs. NAL-NL2

A

Manufacturers fittings are usually “first fit” so there is reduced gain for soft input levels, roll-off above 2000 Hz, boost in the mid frequencies, more linear than prescribed

111
Q

Initial fit vs. NAL-NL1

A

Verified prescriptions were within 4-5dB of target
Initial fit had poorer matches and were significantly different

112
Q

First fit objective summary

A

The HA manufacturer is most interested in initial accpetance of HA sound quality and loudness
This usually results in under-amplifying high frequencies espcially for soft inputs
Overall gain may also be reduced
These are not terrible objectives but the audiologist needs to have full control on what the patient is hearing and then adjust accordingly

113
Q

What are the two recommendations from the AAA task force and explain?

A

Gain verification- prescribed gain from a validated prescriptive method should be verified using a probe mic approach that is references to the ear canal SPL
Output verification- given the importance of avoiding excessive hearing aid output, maximum hearing aid output (OSPL90) verification is recommended to ensure that it does not exceed the patients threshold of discomfort

114
Q

Why is uptake of REM so slow?

A

-REM takes too much time
-inserting a probe mic to the TM is uncomfortable or painful for the patient
-the equipment is expensive and the cost is not justified
-the HA should be adjusted in response to client comments even if the target is initially met so why spend time adjsuting the HA to match a target that you will immediately move away from
-insertion of the probe tube may cause feedback
-with tight earmolds your probe tube may be squashed
-accurate placement is difficult
the advanced features currently available make REM less worthwhile, device is so dynamic this measurement does not help
-audiology operating largely outside of mainstream reimbursement channels when it come to HA dispensing
-audiology is often in an employee role where lack of reimbursement for these aspects of patient care makes it difficult to argue for additional equipment
-lack of quality control of clinical training sites when audiologists are in training
-laziness

115
Q

Where is the money going to come from to pay for REM?

A

REM with live speechmapping reduced the number of follow up tweaking appointments
Less return for credit (RFC)

116
Q

How did the HCC achieve such a low RFC rate?

A

Individually measured LDLs
FCA
Realistic expectation
Encourage participation in our AR groups

117
Q

What can the use of REM improve?

A

Sales, patient confidence and satisfaction, RFC, the financial health of the business

118
Q

When do we repeat REM?

A

Suspect something is wrong with the HA or continued patient complaints
Change in hearing
PJ says every 2-3 years even with stable hearing (output of aids may be totally different then what you thought; a few years of minor changes can add up to a fitting nowhere near prescription)

119
Q

Automatic fine tuning

A

IMC- inter-module communication
The fitting module can “see” what the verification device has recorded and auto adjust programming software
Automated adjustment of gain parameters to meet your chosen prescription

120
Q

Oticon REM autofit

A

IMA between NOAh and the audioscan verifit 2 allows the manufacturer software to fit the hearing aid to targets in a few minutes

121
Q

Explaining REM to patients

A

Easy to confuse patients with professional jargon
Keep it simple, unless patient asks for more explanation

122
Q

Simulated REM

A

HA can be placed in the test box and fit to a prescriptive target using simulated REM or S-REM
Switch verifit screen to test box to speechmapping
Enter real-ear to coupler difference (RECD) measurement for most accurate fitting, otherwise use average values
For verifit 2, need to use specific S-REM test box setup and couplers
Run speechmapping curves at various intensities and match prescriptive targets the same as on ear procedure

123
Q

Pediatric fitting overview

A

REM is non-negotiable
Small children will not sit still during speechmappping so the clinician will take a snapshot of the childs ear canal resonance and then apply that measurement to the fitting
Need to re-measure the RECD as the child grows
Need to use a prescriptive rationale designed for language learning and audibility

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