Building Practice Success Through Speechmap Real Ear...

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Building Practice Success Through

Speechmap Real Ear Measurements

Chris Stokes-Rees

Speaker Disclosure

Relevant financial relationships:

• Audioscan

(Applications Specialist)

• Conestoga College, Kitchener Ontario

(professor, H.I.S. program)

Today’s Agenda

1. REM in a changing landscape

2. UNT study: perceived value of REM

3. Speechmap: review of the basics

4. Speech Intelligibility

5. Live Speech in counselling

6. RIC/RITE and an Open Canal Update

7. RECD: not just for kids anymore

8. Frequency Lowering

9. Simultaneous binaural REM

Real Ear Measurements

in a changing landscape

Evolving Hearing Aid Supply Chain Model

Smriga, D. “Who are we really working for?” presentation at ADA 2014

Evolving Product and Service

Delivery

Expected to…

• Provide improved access to hearing

aids

• Offer lower cost alternatives than

historically available

• Shift focus towards the product as the

solution

How to address ‘product focus’ and

highlight our relevance?

Verification Services

“Real-ear measurement”

Source: Hearing Journal Vol 59 No.4 Apr 2006

Are we conducting REM?

Are we conducting REM?

Mueller and Picou. Use of real-ear probe microphone measures. Hearing Journal, May, 2010.

Some Reasons for NOT using REMs…

• “Too time consuming”

• “Too difficult”

• “Too expensive”

• “You can’t verify X, Y or Z instrument.”

• “Measuring RECD and entering it in our software will guarantee your fitting is right.”

• “Doesn’t make a difference”

“We cannot know what a hearing aid does unless it’s performance is

measured”

Harvey Dillon, NAL Australia

NAL-NL2 REAR Results Using 5 Different Manufacturers’ Programming Software

Sanders, J., Stoody, T., Weber, J., Mueller, H., “Manufacturers’ NAL-NL2 Fittings Fail Real Ear Verification” Hearing Review, March 2015; 21(3): 24-32

55dB

N = 16

65dB 75dB

NAL-NL2 Comparison to 5 Different

Manufacturers’ Proprietary Fittings

Sanders, J., Stoody, T., Weber, J., Mueller, H., “Manufacturers’ NAL-NL2 Fittings Fail Real Ear Verification” Hearing Review, March 2015; 21(3): 24-32

55dB 65dB 75dB

N = 16

The Importance of Audibility

• A 10 year old set of analog hearing aids verified to NAL-R prescriptive targets outperformed the six largest manufacturers’ premium BTE hearing aids programmed to the manufacturer ‘first fit’ in speech-in-noise testing

• After being verified to NAL-R prescriptive targets 5 of the 6 premium digital hearing aids outperformed the 10 year old analog hearing aids

Leavitt, R. J., & Flexer, C. (2012, December 01). The Importance of Audibility in Successful Amplification of Hearing Loss. Retrieved from http://www.hearingreview.com/2012/12/the-importance-of-audibility-in-successful-amplification-of-hearing-loss/

Takeaways

• Selecting a target in programming software does not guarantee that targeted performance will be delivered in the patient’s ear.

• Differences can be substantial and unpredictable.

• The only way to KNOW what you are delivering is through verification measurements.

REM and Patient Satisfaction

82

23

79

32

51

58

6

53

7

31

0 20 40 60 80 100

Measure LDL

Measure Customer Satisfaction

Measure Objective Benefit

Measure Subjective Benefit

REM

Percent of Patients

Below Average Success Above Average Success

Adapted from Kochkin et. al. MarkeTrak VIII: The Impact of the Hearing Healthcare Professional on Hearing Aid User Success". Hearing Review, April 2010.

Perceived Value of REM

The Amlani et al UNT study, 2016

Impact of REM on perception of

hearing aid services

• Study in 2016 at UNT looked at the impact

of REM on the perceived value of service

received

• This unique study very relevant to address

the service vs. product question in hearing

aid delivery

Participants

• 60 subjects, bilateral mild-to-moderate

SNHL

Group 1: “Experienced” users (> 8hrs/d)

Group 2: “In The Drawer” users (< 8hrs/wk)

Group 3: “First-time” users (never tried)

The surveys used

1. WTP (Willingness to pay)

– One-item question indicating maximum dollar

amount individual willing to exchange to

obtain a service or product

2. SERVAL (Perceived Value of service)

– 14-item scale that measures attitude and

behavior toward perceived value

Procedure

• All groups divided into REM and QuickFit

paths.

• Exp and ITD groups given pre-surveys, all

three groups given post-surveys.

• Those on QuickFit path, given post-study

REM and one more survey.

Results - Willingness-to-pay

Results - Loyalty

e.g., “What is the likelihood that you would recommend this provider to family and friends?”

Results - Loyalty

e.g., “What is the likelihood that you would expand your purchase of additional services offered by this provider?”

Results - PERVAL

e.g., “The quality of the service I received was outstanding.”

Results - PERVAL

e.g., “The service provided eases anxiety about how well the product will work..”

Results - PERVAL

e.g., “The overall value of this experience was high.”

Why all this matters?

• Satisfaction of hearing aid users can be

linked to the type of verification services

offered

• Improves perceived benefit and

satisfaction with practicioner

• REM deemed a worthwhile expense

Speechmap

A quick review

The Speechmap Screen UCL (SPL, estimated from threshold)

SPL Threshold (converted from HL)

MAP(Minimum Audible Pressure)

Speech display & analysis

• Percentile analysis used to display the dynamic range of amplified speech.

Maximum levels (peaks or 99th percentile)

Average levels (L.T.A.S.S.)

Minimum levels (valleys or 30th percentile)

• Speech must be analyzed over a period of

ten seconds minimum.

• Prescriptive targets will be shown for the

long term average (L.T.A.S.S.)

Speech display & analysis

The counselling challenge…

Explaining

recruitment!

Use the Speechmap screen:

“Normal” dynamic range

“Reduced” dynamic range

Audiometric Data Entry

Soft Speech

Conversational Speech

MPO

SII

What is it and how can it help me?

Speech Intelligibility Index

• ANSI S3.5-1997 “Methods for Calculation of the Speech Intelligibility Index”

• Gives a numeric quantity that predicts

how much of the speech is audible

– in a graphic sense: how much of the

amplified speech area appears above SPL

threshold

• Unrelated to target formula

Soft Speech

Conversational Speech

SII vs. Predicted CST Score

(from Sherbecoe and Studebaker 2003)

Live Speech

as a counselling tool

Live speech as a counselling tool

• Live speech does not provide an effective,

repeatable test for fitting hearing

instruments.

However, it is a great tool in patient

counselling situations.

Average speech

Spouse’s voice

Compared

RIC/RITE and OC update

RIC dominates the market

http://hearinghealthmatters.org/waynesworld/2016/major-hearing-aid-disruption/

Vent effects on HI Gain

Dome type examples

Common OC mistakes

• Assuming that RIC = Open Canal

• Assuming that a closed dome is 100%

closed

• Attempting to match low frequency targets,

or provide LF gain where more occluding

coupling may be required.

Audiogram entered

Audiogram entered

Step 1: HI present but ‘off’

Step 2: HI turned ‘on’

Comparison

Difference between curves shows amplification reaching TM

How to determine candidacy

1. Position probe tube in ear

2. Enter audiogram and select a fitting

rationale

3. Run 65dB Speech with open ear (i.e.

REUR)

4. Compare LTASS curve with targets in the

sub-1kHz range

First audiogram entered

A good candidate for OC fit!

Second audiogram entered

Not recommended

RECD:

Not just for kids anymore!

RECD – what it is

• Real Ear to Coupler Difference

• Broadband signal measured in coupler

and in ear canal. RECD = difference in

output, across frequencies.

RECD – How it is measured

Frequencies at which

RECD was measured

Measured RECD values

Coupler mic

RECD transducer

RECD transducer

Probe mic

RECD – How it is used

1. Test box verification.

– AKA “S-REM”

– Speechmap simulated in a coupler, in the test

box

Isn’t this primarily

used in pediatric

fittings?

RECD – How it is used

2. HL Threshold correction.

– Used in the HL-to-SPL transformation

– More accurate SPL thresholds

Applicable to any

ear canal that is

not average!

Correcting Thresholds

• When we measure hearing thresholds the audiometer produces a stimulus in the ear

• The actual level in the ear is affected by the acoustics of the ear canal.

• The audiometer is calibrated to an average adult ear...for any other canal the actual threshold measured will be different

• RECD lets us capture what this difference is!

Correcting Thresholds

• Approximately 80% of adult ears exhibit average RECD

• Pro tip: watch for that 20%! When verifying fit on non-average ear canal, measure HL with inserts and use RECD!

Example case

Speechmap test: average RECD

RECD: 3 3 3 3 7 8 10 15 15 11

Speechmap test: entered RECD

RECD: 3 2 3 5 5 8 5 7 11 8

Note On Audiogram Correction...

• There are a number of ways clinicians use to measure the hearing thresholds (audiogram) including:

insert phones headphones sound field speakers

• RECD can only be used to correct the threshold values if the

patient’s thresholds were measured with insert phones

Frequency Lowering

How to adjust for optimal benefit

Freq. Lowering - The Concept

• Some hearing losses have un-aidable

regions where important speech

information exists

• Re-positioning input energy in these

regions to regions that are aidable can

provide access to these important speech

cues e.g. steep sloping HF losses!

Frequency Lowering Today

• In 2017 all high-end hearing instruments

contain this technology!

• Some manufacturers default it to “on” with

default settings.

• To provide best effect it should be adjusted

using the latest protocol.

The ‘s’ and ‘sh’ Stimuli

“S” @ 65dB

“SH” @ 65dB

• Special stimuli for use in adjusting frequency lowering function.

• Developed at University of Western Ontario.

FL Adjustment protocol

1. Run 65dB speech

2. Identify the Maximum Audible Output

Frequency range.

MAOF

Identify MAOF;

Where SPL

threshold crosses

LTASS and where

it crosses PEAK.

MAOF Highlighter

3. Run /s/ stimulus. Adjust so upper

shoulder of /s/ is within the MAOF.

MAOF Highlighter

4. Run /sh/ and check that it does not totally

overlap /s/ signal. Adjust if necessary.

MAOF Highlighter

On Verifit2, activate MAOF highlighter.

1. Run 65 dB speech test

MAOF Highlighter

2. Run /s/ in a separate test. From test

setup in /s/ test, select the test containing

65dB speech.

MAOF Highlighter

MAOF (i.e. target range) highlighted:

MAOF Highlighter

3. Adjust frequency lowering of instrument

so upper shoulder of /s/ is within MAOF.

MAOF Highlighter

4. Run /sh/ and fine-tune if necessary.

FL adjustment tip

• Ideal setting is always the LEAST amount

of frequency lowering that is required to

set the upper shoulder of the /s/ in the

MAOF range.

Simultaneous Binaural

A quick update & tips

Simultaneous binaural Speechmap

• Aids in efficiency and allows verification of

binaural functioning

• Provided in a number of manufacturers’

probe tube systems today

• Equalization at two ears is a challenge

Simultaneous binaural on-ear

• The issue: on-ear soundfield typically non-

symmetrical and uncontrolled

vs.

Simultaneous REM solutions?

• It is not possible to equalize a stimulus in level and spectrum at two places (i.e. each ear) at once.

• Solutions employed currently in the market:

– Average the error

– Select one reference mic (left or right)

– Force sequential measurement

– Provide tool for ideal patient positioning

Points to remember

• The Verifit Binaural Sound Field Assist and

the forced sequential binaural will only

activate if the stimulus at both ears is

>2dB different

• If sound field is even, simultaneous

binaural measurements will proceed with

no user interaction.

Tips for simultaneous binaural

• A good acoustic space is helpful... Keep

away from reflective surfaces

• Patient-to-speaker distance is key... Keep

under 60cm (2 feet).

• Binaural Sound Field Assist is sensitive to

external noises. As with any real ear

measurements, keep room silent.

Also: chris@audioscan.com