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					Wading Through the Hearing Aid Environment: Keep Your Boots On and Eyes and Ears Open
David B. Hawkins, Ph.D. Mayo Clinic Jacksonville Jacksonville, Florida

What Is He Going To Talk About With That Title?
• Variety of things • Guiding Premise: The hearing aid portion
of our field is bizarre!

• Not at all like other health care fields which
have a prosthetic device

• Much of it is related to our strange history • Want to provide you an appreciation of the
strangeness of this field through my eyes, what the public sees, and ways in which we interact with the technology

• Hope to do this with some humor

Why Boots?
• As audiologists involved with hearing
aids, we are often walking through an environment filled with …….uh, MUCK…got to work hard to keep that stuff off of you

1

Why “Eyes and Ears Open?”
• Because we are constantly being
bombarded with marketing and propaganda that may have very little basis in fact or evidence read it in a trade journal or you’re told it by a manufacturer rep or “trainer” or you got CEUs for hearing it functioning in a sales environment for a non-health care product

• Can’t believe something just because you

• It sometimes seems as if we are

Computers Are Dominant in Our Lives Now

• Use them at work • Use them at home • They are in every aspect of our lives • Cars • Cell phones • TVs, DVDs • Even kitty litter boxes

We Are Used to Them, We’re Dependent on Them, But Are They Always Correct In What They Tell Us?

• Do they make mistakes? • If so…..why? • Human error in programming • Simulations are often used
Assume “the mean person” Thus assume individual variability is small or at least deviations from “the mean person” can be tolerated So the assumptions in the programming may not be correct or they may not apply to all people

2

How Do We Use Computers in Hearing Aid Assessment?

• Software prescription programs, e.g.
NAL-NL1 or DSL NOAH modules

• Manufacturer’s software programs in • Ear canal probe microphone
measurement systems

How Accurate Are the Simulations Used By the Manufacturers in NOAH Software?

• Probably differs with each hearing aid
manufacturer use

• What transformations and corrections they • Whether they incorporate earmold effects
such as venting, tubing diameter, etc. corrections

• Whether they incorporate binaural • How deviant your individual patient is

Two Recent Studies Have Addressed the Actual/Simulation Differences

• Hawkins and Cook (2004) • Aarts and Caffee (2005)

3

Actual Insertion Gain Minus Simulated Insertion Gain

10 5

Actual IG Minus Simulated IG (dB

0 -5 -10 -15 -20 -25 0.25 0.5 2 3 4 6

1

Hawkins and Cook (2004)

Frequency (kHz)

Actual 2cc Coupler Gain Minus Simulated 2cc Coupler Gain

10

Actual 2cc Gain Minus Simulated 2cc Gain (dB)

5 0

-5

-10 -15 -20 -25 0.25 0.5

1

2

3

4

6

Hawkins and Cook (2004)

Frequency (kHz)

Mild-moderate sloping loss, 50 dB Input

Measured REAR Minus Predicted REAR

Aarts and Caffee(2005)

4

Measured REAR Minus Predicted REAR
Mild-moderate sloping loss, 90 dB Input

Aarts and Caffee(2005)

What About Other Aspects in Software? Are They Always What You Think?

Program 1 on NOAH Screen

Program 2 on NOAH Screen

5

Actual Program 2

Actual Program 1

How About Those “Automatic” Settings: Do They Always Do What You Think They Will?

L&D Replacement: Reprogrammed Same As Lost Aid, Patient Returns, “Something Isn’t Right With First Setting”

50 dB Input, From Front and Back

6

Now Put in 75 dB SPL, “Automatic” Setting Is Activated, So Noise Reduction and Directional Mic Are Activated. Here’s What It’s Supposed to Look Like

00 Signal

1800 Signal

Here Is What His Hearing Aid Did With 75 dB SPL Input

1800 Signal

00 Signal

Sent It Back to Manufacturer With This Statement on the Repair Form

7

They “Repaired” It…. Here’s What They Did

Did “Repositioning the Receiver” Fix the Problem?

1800 Signal

00 Signal

Clicking on the Directional Mic… Does It Always Do What You Think?

8

Reversed Directional Microphones: It Happens A Lot!

Sent It Back to Manufacturer (not the same one) With This Statement on the Repair Form

They “Repaired” It…. Here’s What They Did

9

Did Replacing the Receiver Fix the Problem?

Another D-Mic Reversal (From Yet Another Company)

Output from 1800

Output from 00

And Another D-Mic Reversal, But Of A Different Sort

Original FR

Changed FR

10

Front-Back Curves After the Minor FR Change

Output from 1800

Output from 00

Can You Believe The “Repair Form” in Other Cases?

You Better Not….

New Aid Goes Back to Manufacturer for Recasing Only
Aid Returns Recased with This Invoice

11

Manufacturer Returned “User Settings”

Actual User Setting

Just 20 dB Off… Result: “e-e-e-e-e-e-e-e!!!”

This Is Fairly Common: An Example From Another Company

Result: “Way Too Loud and So Much Noise!”

Probe Microphone System Simulations of REAR in SPL in the Ear Canal

• Measure the hearing aid in the 2cc coupler • Software applies the following corrections: • REDD to convert thresholds to
estimated ear canal SPLs on style of aid)

• Microphone location effect (depends • Average RECD (may enter) • Will be off if venting, etc. isn’t factored in
and if patient’s RECD is different from the average RECD

12

Simulation

Actual Measurement

Pretty Good!

Simulation

13

Actual Measurement

Not so good, see 1.5k & 4k

Simulation

Actual Measurement

14

Simulation

Actual Measurement

Simulation

15

Actual Measurement

Binaural Fittings Are The “Screens” Complete?

• We all know about “binaural
summation”

• At threshold: 3 dB • At MCL: 5-6 dB • At LDL: 0-2 dB (10 dB if loudness

matching at high levels, but it’s loudness discomfort we are concerned with, and it’s negligible)

Do NOAH Generated Targets Take Into Account Binaural Summation for Gain?

• Gain • NO

•

ReSound Oticon Phonak Widex YES Siemens (reduce 3 dB) Starkey (reduce 3 dB) Unitron (reduce 2-3 dB) Sonic Innovations (reduce 2 dB)

16

Do NOAH Generated Targets Take Into Account Binaural Summation for Maximum Output?

• Maximum Output • NO

•

ReSound Oticon Phonak Widex YES Starkey (reduce 1-2 dB) Siemens (reduce 3 dB) Unitron (reduce 2-3 dB) Sonic Innovations (reduce 2 dB)

So What Do You Need to Do?

• Make sure you take binaural

summation into account in your fittings has taken care of this variable

• Don’t assume that “software”

Those “First Fit” Algorithms

• What do they recommend? • Are they all the same? • Do they make speech signals
audible?

17

FIRST FIT
10/2004

50 FLAT LOSS
DEFAULT FIRST FIT 65dB SPEECH
40

Apherma F180A FULL SHELL GNReSound CANTA 770-D BTE Oticon Adapto BTE Phonak Claro BTE Siemens Triano 3 BTE Starkey Axent AV MM BTE Widex SD-19M BTE

Gain (dB, 1/3 Octave)

Bentler & Chiou

30

20

10

0

-10

-20 125 250 500 1000 2000 4000 8000

Frenquency

Do the First-Fit Algorithms Make Speech Audible for New Users? Answer: Often Not

• Choose 3 major manufacturers • Put a flat 50 dB HL audiogram into NOAH • Asked the manufacturer’s software to do
“First Fit” for a new user, used their ITE

• Using the AudioScan Verifit in the

simulated real ear measurement mode, looked at where speech is amplified to for 2 levels of real speech as input: 55 dB SPL (soft speech) and 70 dB SPL (average speech input)

Manufacturer A, New User, Soft Speech Input

18

Manufacturer A, New User, Average Speech Input

Manufacturer B, New User, Soft Speech Input

Manufacturer B, New User, Average Speech Input

19

Manufacturer C, New User, Soft Speech Input

Manufacturer C, New User, Average Speech Input

What About A Long-Time Hearing Aid User?

• Does amplified speech come • Are the various companies
different?

close to something like NAL-NL1 targets?

20

Manufacturer A, Long-Time User, Average Speech Input

Manufacturer A, Me Adjusting to NAL-NL1, Average Speech Input

Manufacturer B, Long-Time User, Average Speech Input

21

Manufacturer B, Me Adjusting to NAL-NL1, Average Speech Input

Manufacturer C, Long-Time User, Average Speech Input

Is It All A Mess? NO!!

• I have been working with hearing aids
for 30 years!

• This is an exciting time… • Rapid developments • Better products • More frequency shaping • Directional mic developments • More gain before feedback • “Noise Reduction” may

increase comfort and perhaps one day intelligibility

22

• More compression options • Expansion • Early “automatic” settings • Just beginning to tap the potential
the audiologist power of “digital signal processing”

• Time of optimism and excitement for • But…we’re not going to “solve the
problem” any time soon…

Conclusions
1. Realize that SIMULATIONS ARE
SIMULATIONS, not reality

2. You shouldn’t expect them to be
accurate all the time….why? “Because the world is normally distributed!” AND “Because software algorithms aren’t perfect”

Conclusions
3. Verify that what you have is what you
think you have

4. Make real-ear and electroacoustic

measurements routine in your practice software or manufacturer quality control. It’s your responsibility as the audiologist to be sure hearing aids work as you want them to and as they are supposed to!

5. Listen to all hearing aids!! Do not trust

6. Ask for evidence, not marketing slogans

23

Final Conclusion
7. Finally, keep your boots on and eyes and
ear open!! “Things are not always as they seem!”

What Am I Really Doing to My Patients?
Vanderbilt Bill Wilkerson Center For Otolaryngology and Communication Sciences Nashville, Tennessee

Hearing Aid Technologies: Clinical Decision Making
Todd A. Ricketts, PhD

24

Some Questions Related to Hearing Aid Technology

Is “Level of Technology” a Valid Hearing Aid Selection Model? Perhaps for Sales and Marketing – However, clinical selection should not be a question of “level of technology” – But rather: What are the patients needs and based on the evidence what features and processing will address those needs

How Does it Work? What Does It Do?
Does It Really Do What It Is Supposed To? How Does It Interact With Individual Patients and the Environments They Are In? Evidenced Based Practice

25

Satisfaction = Expectations Met
Counseling: What Do Current “High Tech” Hearing Aids Really Do?

Examining Features

• No hearing aid has emerged as the “winner” (some
patients will NOT be able to tell the difference for some features)

• What does each of the features really do? • Cost to benefit ratio must be considered. But

issues other than only word recognition must be evaluated (e.g. sound quality and importance of specific features to user and fitter)

Breaking Down the Evidence

•

Efficacy: Can the treatment work under optimal laboratory conditions? 1. Efficacy+: Can the treatment work in simulated real world
environments?

•

Effectiveness: Does the treatment work under typical conditions? 1. Partial Effectiveness: Does the treatment work in real world 2. 3.

situations? (It is fit appropriately and the user uses it appropriately and receives benefit) Partial Effectiveness+: Does the treatment work in real world situations? (Usual clinical fitting and usual user abilities – benefit still received) True Effectiveness: The benefit that occurs in real world situations is large enough that the patient notices it and it is demonstrated in outcome measures.

26

Some Common Features in “High Tech” Hearing Aids
• Digital noise reduction • Digital feedback reduction • Selective speech enhancement/Reverberation
suppression

• Frequency compression/Frequency
transposition

• Data logging • Directional microphones (Automatic/ Adaptive) • Open canal (OC) fittings

Most: When Speech is Present - Do Nothing

Digital Noise Reduction (DNR)

•

Most examine input and try to quantify whether it is primarily “noise” or “speech” • Determination based mainly on the temporal modulations – may also include level, co-modulations, and/or spectral factors (range, peak, peak frequency relationships). • Generally assumes if signal has temporal modulations or co-modulations similar to speech, it’s speech – otherwise (e.g. steady state) classified as noise. • Gain is reduced in channels where speech is NOT detected. Often the more “noise like” (poorer estimated SNR) the more gain reduction. Systems vary greatly in magnitude of peak gain reduction (~1-18 dB) and speed (>1 ms to 20+ seconds).

•

Evaluating DNR with Probe Microphone Equipment
• Why Evaluate DNR? • Expected benefits only in “steady state”
environments

• Data from Dreschler • Watch DNR time course and magnitude (maximum
attenuation) in the presence of a steady state test signal • What happens to real ear output? • What happens when you speak?

• Select an appropriate test signal • Speech/modulated versus steady state signals • How about music and other signals?

27

DNR Data: Part 1
• Walden et al (2000) • “Improved listening comfort but little
change in speech understanding.”

• Boymans & Dreschler (2000) • “No extra benefit from the combined use
of noise reduction and directional microphone (condition) over directional microphone (condition) alone.”

• Alcantara et al (2003) • No improvement for SRTs; no decrement
for sound quality while listening to four different kinds of background noise

DNR Data Part 2: Evidence (efficacy) For Improved Sound Quality?
100 90 80

Percent of Time Preferred

70 60

50 40 30 20 10 0 Dir Low Noise Dir High Noise Omni Low Noise Omni High Noise

DNR On DNR Off

Listening Condition

DNR Data Part 3: Speech Recognition?
Subject Performance on the HINT in Steady State Noise
5 4.5 4 HINT Threshold 3.5 3 2.5 2 1.5 1 0.5 0 HA-S No DNR HA-S Active DNR HA-F No DNR HA-F Active DNR Hearing Aid Type and Program

28

Impact of Competing Noise Type: Is it Just a Gain Thing?
3 3

2.5 2.5

2 2 DNR Benefit (dB) DNR Benefit (dB)

1.5 1.5

1 1

0.5 0.5

0 0 Steady Steady Modulated Modulated 6 Talker 6 Talker 2 Talker 2 Talker Average Average

Why Doesn’t DNR Improve SNR More? The NRI and Other Misleading “Bench-Top” Measures

The Moral?
• Avoid Bench-top measures that have
not been Validated appropriately!

• There should be evidence that

processing that leads to a change in the bench top measure also leads to concomitant change in patient outcome measures

29

Digital Feedback Reduction Methods
•
Digital Feedback Reduction/Suppression (DFR/DFS) • Hearing aid constantly monitors for feedback and reduces gain within a frequency band when feedback is detected. Adaptive Notch filtering Adaptive feedback cancellation/frequency shifting/etc. Goals? • Improve “Gain Headroom” (static pathway). • Allow for open canal fit (static pathway). • Reduce problems with dynamic feedback path.

•

Evidence That it Works? (Freed and Soli; Johnson & Ricketts; Ricketts & Johnson; Trine et al).

• Gain Margin? • Expected positive in potential for reduced feedback
and/or reduced occlusion.

• Great variability in effectiveness (even with the same • Dynamic Feedback Path? • Great variability in speed (even among those that work)
– <1 to several seconds. measurement method) – 0 to 12-15 dB.

• Potential Negatives • Data to date suggests that the cancellation systems
generally do not appear to negatively impact sound quality, at least in non-reverberant environments Artifacts from tonal sounds in the environment? Impact of Adaptive Notch Filtering?

Speech Enhancement In Current Commercial Hearing Aids
• Spectrally Based (Spectral Sharpening) • One of the earliest research methods • Early attempts often reduced speech intelligibility • New methods show slight improvements in speech
intelligibility in noise

• Spectro-temporally Based • Based mostly on temporal modulation patterns • Works by increasing gain for signals after a modulation that
“looks like” that of a consonant following a vowel SNR)

• Only expected to offset audibility problems (won’t improve • Little validation to this point • Temporal Based – De-reverberation Algorithms • Temporal filter used to reduce level for signals identified as an
echo

30

Frequency Compression/ Frequency Transposition • First Marketed by AVR Sonovation • Transonictm (Frequency Transposition)
Improved awareness but no improvement in speech recognition, even with considerable training ImpaCttm (Frequency Compression) Small improvements in speech recognition (Tyler et al), but problems with sound quality

•

• Reinventing Frequency Transposition?

Data Logging

• As an Aid in Fitting? • No use of a certain program • VCW settings always at max • Self fitting hearing aids? • Do the patients really know
what they want?

Directional Benefit: Efficacy?
• Average hearing aid wearers will receive a directional advantage of ~
3 dB (~25%) in cases in which: • The sound source of interest is in front and near • Competing noise is behind or surrounds the listener • Reverberation is moderate or less • The instrument has a high average DI (3.5 – 5.5 dB) Hawkins and Yacullo, 1984; Killion, et al., 1988; Nielsen & Ludvigsen 1978; Preves et al, 1999; Pumford et al, 2000; Ricketts, 2000a; 2000b; Ricketts, Lindley & Henry, 2001; Ricketts & Henry, 2002; Ricketts & Hornsby, 2003; Ricketts, Hornsby & Johnson, 2005; Valente et al, 2000; Voss 1997; Wouters, Litere & van Wieringen, 1999 environments represent approximately 1/3 of active listening for adults

• Data from Walter Reed (Walden et al) indicates that these

31

Efficacy Continued: Some Fitting Factors Impact Laboratory Directional Benefit Others Don’t!
• Negative Impact? • Venting • Microphone port alignment/azimuth? • Bad design, microphone mismatch, dirt • Little or no Effect? • Monaural versus binaural fitting
Similar Directional BENEFIT – better performance in binaural!

• Dual (omni) Microphone versus Directional + Omni?
Similar theoretical benefit in a uniform field DUAL allows for other processing such as adaptive and multi-channel directivity • Use of/type of compression • Hearing aid style? More benefit with BTE (over custom), but similar performance in directional mode

Directional Mode and Special Populations?
• Severe-to-Profound? • Less benefit per dB change in DI
(SII predictable) but still significant benefit

• School aged children • Same potential for maximum
benefit, but… Switching concerns Listening environment and attentional factors

Adaptive Conclusions
• Adaptive advantage mainly supported in the presence of
discrete competing stimuli • Consistent across Bentler et al/Ricketts et al • Past research has suggested this limitation is a problem inherent to adaptive technology (Greenberg & Zurek, 1992; Kates & Weiss, 1996; Peterson, Durlach, Rabinowitz & Zurek, 1988; Woods and Trine, 2003) data suggest the dominate source needs to have an intensity of approximately 15 dB greater than other sources to effect a change in the adaptive sensitivity pattern

• In moderately reverberant, multiple source environments STI

• Multi-channel Adaptive Directionality – Potential Benefits? • No evidence to date, but theoretical potential in wind
noise

32

Directional Benefit and Effectiveness?: Pretty Weak!

• Valente, Fabry and Potts (1995): Showed
slight, but significant improvements on PHAB BN and RC subscales

• Preves, Sammeth and Wynne (1999):

Showed benefit on RV and BN subscales for a compensated directional aid versus omnidirectional better on the CST, but no significant differences on the PHAB

• Walden et al. (2000): Subjects performed

Importance of Scale Sensitivity!
60 40

11% 9% 7%
Omni D-Full Time D-Switch

Benefit (% )

20

0

-20

-40 SF SBL

Sub-Scale

Conclusions
• Results suggest that laboratory directional
benefit as measured by speech recognition can be reflected in self assessment measures of hearing aid benefit. questions are concentrated on listening in noise when the sound source of interest is in front of the listener and noise is behind. directional use.

• However, benefit is more obvious if

• Results generally did not support full-time

33

Open Canal Fittings?
• Still Not very much data • Supported by Sales figures • Obvious benefits • Alleviate occlusion • Improved sound quality due to use of natural signal • Limitations • Only appropriate for HF hearing loss
Accept less benefit because of fewer negatives?

• Retention and very small (dexterity) • Directional benefit limited to ~1/2 (or less) – interacts
with cosmetics

Verification: Probe Microphone Measures are Possible and Recommended for All Modern Hearing Aids!
• Determination of real ear output at several input levels (e.g., soft,
moderate, loud) will provide a more complete picture of audibility – Data: Audibility important – Many are still too loud

• Interaction between signal processing and testing method is critical! • Using a signal the hearing aid thinks is speech is critical for
assessing audibility of speech

• Recent other pitfalls and mistakes – Open fittings • Not disabling the reference microphone • Assuming that you get “free output” based on overcoming REOG
Lose a lot in the lows, gain some highs with same gain settings (~8-10 dB peak in the highs due to resonance and impedance differences) • Assuming the Maximum Gain (before feedback) is from open

REAR Open Versus Closed – Same Instrument.
Closed Open

34

A Clinically Applicable Electroacoustic Measure of Directivity – FBR

• Ratio of the output level of a hearing aid for the same
sound source placed directly in front (0 degree azimuth) versus directly behind the listener (180 degree azimuth)

• Easy to obtain clinically using real-ear system • Determine if the directional microphone is working
and fitting effects on directivity (e.g. venting) • Consider evaluating at fit and at re-testing hearing aids

• NOT for comparisons of absolute directivity across • Measure with hearing aid in linear (not compression)
mode or better yet, establish clinic norms

Real Speech Versus Live Speech: Potential Pitfalls
Standardization? Targets?

Swept Pure Tone and DFS/DNR? Many Times it is OK!

35

Functional Gain and Other Verification Methods for Digital Hearing Aids?
Why not just ask how it sounds? Why not trust the “fitting screen”?

One Manufacturers “NAL-Fit” on a Real Ear

Pitfalls of Functional Gain Testing
• Contribution of non-test ear • Step size • Reliability • Ambient noise/hearing aid masking effect Additional Digital Pitfalls • Impact of DNR • Effects of Expansion • Impact of very LT Compression

36

Do You Want High Levels Of Functional Gain?
Linear
120 110 100 90 80 70 60 50 40 30 20 0 20 40 60 80 100 120

Compression LT

Compression VLCT

Output (dB)

Unaided Threshold

Input (dB)

Aided Threshold Measures can be useful for verifying audibility of soft sounds – but can lead to misleading information when attempting to extend to verification of average and loud speech input levels!

Questions?

37

Hearing Aids and Cochlear Implants: Merging Technologies
Jon K. Shallop, Ph.D. René H. Gifford, Ph.D. Jodi Cook, Ph.D. Mayo Clinic and InSound Medical
CP1120443-1

Introduction: Dr. Jon K. Shallop

38

Factors: Things Are Changing
• Smaller cochlear implants • Surgery Techniques • Smaller incision • “Softer” approach • “Smarter” modiolar electrodes • Nucleus Contour • Advanced Bionics Helix • “Hybrid” devices

Two Approaches to CI Hearing Preservation
• • • • • •
“Standard electrodes” Longer 20-30 mm Lateral wall vs. … Peri-modiolar Scala tympani Surgeon uses “soft” techniques

• • • • • •

“Hybrid electrodes” Shorter 10-20mm Straight & compact Center of scala tympani Scala tympani Surgeon uses “soft” techniques

• All frequencies • Hearing aid optional

• Hi-frequencies • Used with hearing aid

Hybrid Cochlear Implant
Acoustic stimulation of low frequencies via Ipsilateral Hearing Aid Electrical stimulation of high frequencies via Cochlear Implant

39

= Lateral Wall of Cochlea
= Electrode 1 = Electrode 22

Lateral Wall Placement

N24M Peri-modiolar 270° Placement

N24R
400°

Schematic of Nucleus Hybrid Electrode Array

10 mm electrode placed in scala tympani

Nucleus® Hybrid™ Cochlear Implant
• Based on the Nucleus
24 cochlear implant Electrically equivalent • Short array (10 mm) composed of 6 halfband electrodes (to make array as thin as possible) • Designed to allow electric stimulation of high-frequency region of the cochlea while maintaining lowfrequency hearing for acoustic stimulation

40

Med-El 20mm Cochlear Implant

12 channels x 20 mm

The CI24RE Hybrid Implant Clinical Trial requires patients to use an ITE hearing aid in the same ear as the implant Solution ??? We connect the Freedom BTE SP to the ITE using a short plastic “stump” which we secure to the ITE and then connect to the SP ear-hook with tubing that “lifts” the SP slightly

ITE Short Plastic “Stump”

41

US02 HYB 1131

US01 HYB 1131

MED-EL DUET – EAS
Combined Device
• Increased user comfort • Only one device • One set of batteries • Same input signal for electric
and acoustic stimulation

• HA focus on low frequencies • Better use of Assistive

Listening Devices (FM systems) • Audio input feeds both electric and acoustic stimulation

42

Nucleus Hybrid Criteria FDA Clinical Trial
• Initiated by Bruce Gantz, MD and
colleagues at the University of Iowa in 1999, as an FDA regulated feasibility study additional surgeons/sites and 25 additional subjects

• Study broadened late 2002 to include • Broadened once again in 2005 to

include a maximum of 100 subjects total

Nucleus Hybrid Criteria FDA Clinical Trial
CI Hybrid 2005 >15 years old CNC Words:
* 10 - 60% Implant ear * <81% contra ear * English primary * Normal speech/language ** Note: Medicare patients can have up to 60% correct on HINT sentences

Definitions: Hybrid
• Hybrid Stimulation:
Use of acoustic hearing, via amplification, in addition to electric hearing via a cochlear implant in the same ear

CI + HA

43

Definition: BiModal
• Bimodal Stimulation:
Use of acoustic hearing, via amplification, in addition to electric hearing via a cochlear implant in the opposite ear

HA

CI

Definition: Combined
• Combined Stimulation:
Use of acoustic hearing bilaterally, via amplification, in addition to electric hearing via a HA cochlear implant. That is, a combination of the hybrid and Bimodal conditions

CI + HA

Hybrid Cochlear Implant

Results

44

Gantz and Turner 2004 (Acta Otolaryngol 124 344-347)
Mean Unaided Audiometric Data US 10 mm Subjects (N=24)
-10 0 10 20 30 40 50 60 70 80 90
Preoperative Initial Activation

Hearing Threshold (dB HL) (ANSI - 1989)

Mean LF (.125-1k Hz) Shift = 12.2 dB

100 110 120 130 140
125 250 500 750 1000 1500 2000 3000 4000 6000 8000

Frequency (Hz)

Case 1

X O

X O

Hybrid US01 HYB 1131 Pre-op Audiogram O X X O X O X X X O XX O O O O

Case 1

Hybrid US01 HYB 1131

Implant in place

45

Case 1

Hybrid US01 HYB 1131

Hybrid US01 HYB 1131

Hybrid US01 HYB 1131

46

Case 1

Hybrid US01 HYB 1131
02-2006 Initial Activation

Hybrid US01 HYB 1131
02-2006 Pre-op & Initial Activation

Pre-op 9-2005

Post-op 2-2006

Case 1

47

Hybrid US01 HYB 1131 CNC Words 6 months post-op
50 45

Percent Correct

Case 1

40

35

30

25

CNC 6 mo IPSI HA CNC 6 mo R+L HA CNC 6 mo CI CNC 6 mo COMB

20

15

10

5

0 1

Aided Condition

Pre- to Postoperative Change in LF (125-1k Hz) Thresholds
110 +75 +60 +45 +30 +15 0

Postoperative Hearing Threshold (dB HL)

100 -15 90 80 70 60 50 40 30 20 20 30 40 50 60 70 80 90 100 110

Nucleus
Hybrid Clinical Trial to date Nov. 2006

3 Months Postactivation N=57 No Response at any Frequency

Preoperative Hearing Threshold (dB HL)

Speech Recognition Outcomes
CNC Words
100 Implanted Ear
HA Ipsilateral Hybrid Bilateral HA Combined

Bilateral Condition Matched Pre and 6m

Nucleus
Percent Correct

90 80 70 60 50 40 30 20 10 0
14.9%

Hybrid Clinical Trial to date Nov. 2006

p<0.001 p=0.003 20.4%

Unilateral N = 31

Bilateral N = 31

48

Speech Recognition Outcomes
BKB-SIN
16 Implanted Ear Matched Pre and 6m Bilateral Condition
HA Ipsilateral Hybrid Bilateral HA Combined

Hybrid Clinical Trial to date Nov. 2006

Speech Reception Threshold (dB SNR)

Nucleus

14 12 10 8 6 4 2 0

3.3 dB

p=0.011

p<0.001

3.5 dB

Unilateral N = 31

Bilateral N = 31

Familiar Melody Recognition
…………………………………………………. Subjects: Normal Hearing (NH) vs Short Hybrid electrode (SE) vs. long electrode (LE).
87.1

Percent Correct

90 80 70 60 50 40 30 20 10 0

84.2
NH (N=17) SE (N=5) LE (N=27)

30.7

Hybrid subjects significantly more accurate than long electrode subjects. p<.0004)
Courtesy Kate Gfeller, PhD, University of Iowa

Findings of Hybrid Study - 1
• Electroacoustic stimulation is superior • Patients are able to combine electric
to acoustic or electric stimulation alone for word recognition in quiet and acoustic information contralaterally (Bimodal) as well as ipsilaterally (Hybrid) • But generally, the best performance is obtained when both hearing aids and the cochlear implant are used together

49

Findings of Hybrid Study- 2 • Individual performance varies
widely (like regular implant recipients) • Some patients with significant loss benefit, some do not • Some patients with little change in hearing do not show benefit, most do • Hybrid patients appear to improve over a longer period of time

Findings of Hybrid Study- 3
• Electroacoustic stimulation is superior
for understanding speech in noise and music perception, compared with long electrode array subjects • Preserved low-frequency hearing allows for better pitch discrimination abilities

• These latter results, in particular, set

Hybrid users apart from conventional cochlear implant users

Introduction: Dr. René H. Gifford

50

Electric and Acoustic Stimulation (EAS) with a 20-mm array (MED EL)

Data were collected at the International Center for Speech and Hearing in Kajetany, Poland Prof. Henryk Skarzynski and Drs. Artur Lorens, Anna Piotrowski, Michael Dorman & Tony Spahr

Electric and Acoustic Stimulation (EAS) with a 20-mm array (MED EL)

0 20 40 60

C32M

M33M

J53S

threshold (dB HL)

80 100 120 0 20 40 60 80 100

M28J

B59S

0.125 0.25 0.5

1

2

4

8

PREimplant
120 0.125 0.25 0.5 1 2 4 8 0.125 0.25 0.5 1 2 4 8

frequency (kHz)

Med El 20 mm EAS Patients – Kajetany, Poland

51

0 20 40 60

C32M

M33M

J53S

threshold (dB HL)

80 100 120 0 20 40 60 80 100 120 0.125 0.25 0.5 1 2 4 8 0.125 0.25 0.5 1 2 4 8

M28J

B59S

0.125 0.25 0.5

1

2

4

8

PREimplant POSTimplant

frequency (kHz)

Med El 20 mm EAS Patients – Kajetany, Poland

HSM Sentences in Noise (4-Talker Babble)
0

C32M

Pre-implant binaural aided +5 dB SNR: 39% Post-implant combined EAS +5 dB SNR: 80%

threshold (dB HL)

20 40 60 80 100 120 0.125 0.25 0.5 1 2 4 8

frequency (kHz)

Med El 20 mm EAS Patients – Kajetany, Poland

HSM Sentences in Noise (4-Talker Babble)
0

M33M

Binaural aided acoustic 0 dB SNR: 50% Combined EAS

threshold (dB HL)

20 40 60 80 100 120 0.125 0.25 0.5 1 2 4 8

0 dB SNR: 92%

frequency (kHz)

Med El 20 mm EAS Patients – Kajetany, Poland

52

HSM Sentences in Noise (4-Talker Babble)
0

threshold (dB HL)

M28J

Binaural aided acoustic +5 dB SNR: 46% Post-implant combined EAS

20 40 60 80 100 120 0.125 0.25 0.5 1 2 4 8

+5 dB SNR: 97%

frequency (kHz)

Med El 20 mm EAS Patients – Kajetany, Poland

HSM Sentences in Noise (4-Talker Babble)
0

threshold (dB HL)

B59S

Binaural aided acoustic 0 dB SNR: 40% Combined EAS

20 40 60 80 100 120 0.125 0.25 0.5 1 2 4 8

frequency (kHz)

0 dB SNR: 99%

Med El 20 mm EAS Patients – Kajetany, Poland

Standard, Full-insertion Array

Cases of low-frequency hearing preservation

53

Case Study: 42 Y Female

• Progressive bilateral

sensorineural hearing loss diminished gradually

• Successful use of hearing aids • Qualifies for a cochlear implant • Postop audiograms show
significant residual hearing

Case 2: Hearing Preservation With Full Length CI24M RCA

Pre-op

Post-op 10 month

* significant hearing has been preserved with a long electrode array
CI24RCA 5-04 CLWD

Case 2: Hearing Preservation With Full Length CI24M RCA

Pre-op

Post-op 2y 4 months

x O

x O x O x O x O x O O OO

* significant hearing has been preserved with a long electrode array
CI24RCA 5-27-04 CLWD

54

HP 03

Case 2: Hearing Preservation With Full Length CI24M RCA

Hi Resolution CT Scan results: “Her electrode array is clearly in the ST. Glad to hear she is doing well.” John Lane, M.D. Radiology 10-12-2006

Post-op 2y 4 months

? Is the electrode array impeding the traveling wave and producing a 15-20 dB conductive shift ? She continues to wear 2 hearing aids with her cochlear implant. cc: remains as bilateral tinnitus

HP03 “Hybrid Qualified”
100 80 60 40 20 0 Pre-op 5 mo 28 mo

Hint CNC W CNC Ph

HP03 “Hybrid Qualified”
100 80 60 40 20 0 Pre-op 5 mo 28 mo

Hint CNC W CNC Ph

55

HP03 “Hybrid Qualified”
100 80 60 40 20 0 Pre-op 5 mo 28 mo

Hint CNC W CNC Ph

HP 09

HP09 45yM
CI24RCA Right 12-05 CLWD pre and post audiograms

HP 09

Post-op 3 weeks

Pre-op

56

HP 09

Post-op 6 weeks

Pre-op

HP09 “Hybrid Qualified”
100 80 60 40 20 0

HINT CNC W CNC Ph Pre-op 1 mo 10 mo

HP09 “Hybrid Qualified”
100 80 60 40 20 0

HINT CNC W CNC Ph Pre-op 1 mo 10 mo

57

HP09 “Hybrid Qualified”
100 80 60 40 20 0

HINT CNC W CNC Ph Pre-op 1 mo 10 mo

Summary – EAS
• Hearing Preservation is possible
with short and long electrode arrays

• EAS can provide significant

benefits with ipsi-lateral and contra-lateral acoustic signals of the mechanisms which may cause changes in residual hearing

• We need to gain better understand

Introduction: Dr. Jodi A. Cook

58

Hearing Aid Evaluation Cochlear Implant Candidate

• Criteria for implantation is
changing

• Previously used power hearing
aid trial prior to implantation hearing aids

• Today, many patients have • Are these hearing aids providing
maximum benefit?

Initial Candidacy Evaluation

• Electroacoustic evaluation • Earmold/shell evaluation • Real-ear evaluation • Adjust amplification as
necessary

Initial Candidacy Evaluation User Variables • Patients often experience loudness discomfort

• Some use program 2

regularly which reduces the gain low setting

• Some turn the volume to a

59

US01 HYB 1131 Initial REM
AVR Sonnovation ITE

Hybrid US01 HYB 1131
Adjusted to Attainable NAL-NL1 Targets

AVR Sonnovation ITEs

Post Implant Hearing Aid Follow Up

• Any residual hearing? • Need to know the cross over
frequency to set hybrid/hearing aid combination

• Readjust the non-implant ear

to balance the combination of the two or three

60

US02 HYB 1131 History

US02 HYB 1131 Hearing Aid History
• 11/01/01: Patient reluctantly
agrees to a CIC in right ear only

• 1/09/03: Discuss limitations of
CIC; recommend binaural hearing aids

US02 HYB 1131 Pre-op

61

Hearing Aid Consult
• 6/24/05: Patient has many communication
difficulties causing him to be quiet and withdrawn; Recommend binaural

• 7/7/05: Fit with binaural hearing aids for

one month trial before Cochlear Implant evaluation

• 8/25/05: Meets criteria for Hybrid • 9/29/05: Fit ITE in the right ear (C.I. surgery
scheduled 12/20/05)

US02 HYB 1131 ITE Fitting in Ear to be Implanted

1/12/06: Re-programming After Threshold Shift

62

US02 HYB 1131 3 month Follow up Post-Implant

US02 HYB 1131 3 month CNC Word Scores
100 80 60 40 20 0 IPSI HA Implant HA AU Hybrid BiModal Combined

Hybrid Post-op Issues
• How many frequencies do you reach
with the hearing aid? after surgery?

• Is the hearing aid still appropriate • What is the purpose of the hearing
aid? • Speech • Music • Quality of sound

63

Hearing Preservation (HP01) 42y Female
• Progressive sensorineural hearing loss with
reduced ability to communicate effectively as a research coordinator

• She received a full electrode array cochlear
implant in her right ear and every attempt was made to preserve her hearing in the implanted ear

• Minimal attention to hearing aid left ear until 10
months post implant

HP 01 REM

Initial Setting-left ear

Reprogram 10 mo

HP01 with Hearing Aids + CI 60 dB SPL
HINT Sentences Quiet
100 100 94 94 59 59 64 64 70 70 80 80 60 60 40 40 20 20 0 0

% Correct

HA-AU Pre

CI+HA AU CI+HA AU CI+HA AU Initial Prg 1 mo 10 mo

64

Summary Issues
• Hearing aids are a critical component
of a successful cochlear implant user, especially Hybrid patients.

• Combination of devices helps the
quality of sound and the patient’s enjoyment of their treatment

patients with speech understanding

• Combination of devices improves the

Future of Hearing Aids and Cochlear Implants
• There is not a clear division between
cochlear implant and hearing aid users

• Audiologist can share learning from
implants and hearing aids to be a better program

• We will need to become a treatment

center and not just focus on hearing aids or cochlear implants

Acknowledgements
• Janalene Niichel • Melanie Meldrum • Rachel Amorim • Ann Roeder • Mayo ENT Surgeons • Charles Beatty, M.D. • Colin Driscoll, M.D.

65

Is Two Always Better Than One?
Comparing bilateral implants with one implant plus contralateral hearing aid.
Helen E. Cullington, M.Sc University of California, Irvine Irvine, California

CP1120443-1

This Presentation

• Advantages of two ears • Bilateral cochlear implants • Bimodal stimulation • Bimodal bilateral comparison • Conclusion

66

Is Two Always Better Than One?

is better than

is better than

67

Advantages of Two Ears

• Head shadow effect • Binaural squelch • Binaural redundancy • Localization

Advantages of Two Ears

• Head shadow effect • Binaural squelch • Binaural redundancy • Localization

Head Shadow Effect

68

Advantages of Two Ears

• Head shadow effect • Binaural squelch • Binaural redundancy • Localization

Binaural Squelch

• True binaural effect • Relies on brainstem nuclei

processing and comparing different auditory info at each ear auditory objects

• Helps separate sounds into

Advantages of Two Ears

• Head shadow effect • Binaural squelch • Binaural redundancy • Localization

69

Binaural Redundancy

• True binaural effect • Duplication of auditory info at
each ear gives some redundancy

• Increases loudness by 2-3 dB

Advantages of Two Ears

• Head shadow effect • Binaural squelch • Binaural redundancy • Localization

Localization
• Judgment about direction and
distance of sound

• Main method - comparison of signals
received at each ear • Interaural intensity difference (high freq) • Interaural time difference (low freq)

70

Normal-hearing
useful

Normal-hearing People

is better than

Hearing Aid Users

is better than

71

Cochlear Implant Users

?
is better than

Cochlear Implant Users

Bilateral Cochlear Implants

• Which aspects of binaural
processing can they use?

72

Advantages of Two Ears

• Head shadow effect • Binaural squelch • Binaural redundancy • Localization

Normal-hearing Listeners

• Binaural hearing requires

precise comparison of timing and intensity cues between the ears

Limitations for Bilateral CI

• Mismatches in frequency
representation

• Processing schemes distort intensity
and timing cues

• Precise timing information not

available because the 2 implants function independently

73

Benefits of Bilateral CI

• Improved localization • Improved hearing in background • Subjective benefit • Best ear always implanted

noise, especially when sources are spatially separated

Disadvantages of Bilateral CI

• Loss of residual hearing • Additional surgery and hardware • Risk of complete loss of
vestibular function

• Cost

Limitations of CI

• Listening in background noise • Music appreciation • Understanding tonal languages • Perceiving tone of voice • Identifying different talkers

74

Pitch!

Envelope and Fine Structure

CI Speech Processing

75

Current CI Systems

How to Help?

• Addition of fine structure may
improve pitch perception

• Easiest way to add some fine
structure …….?

• Add some natural acoustic info

1985 CI Candidacy

• Hearing loss > 100dB • No discernable communication
benefit from hearing aids

76

Current CI Candidacy

• Hearing loss > 70dB • Sentence scores ≤ 50% in

implanted ear, ≤ 60% in nonimplanted ear

CI Candidacy

Original CI candidacy

Current CI candidacy

2 Ways to Present Low Frequencies:
• Contralateral to CI - • Ipsilateral to CI bimodal stimulation hybrid stimulation

77

Hybrid Stimulation

Add Natural Low Frequencies

Bimodal Stimulation

78

Example: 3 Bimodal Users
100 80 60 40 20 0 100 80 60 40 20 0 0 5 10 15 20 0 5 10 15 20

CI + HA

% correct

CI alone HA alone
Mean

SNR

Sentences with female masker

Bimodal Training

• http://www.cochlearcollege.com

Sentences In Quiet

79

Sentences In Noise (0º)

Sentences In Noise (90º)

Measuring Localization

80

Horizontal Localization

Subjective Benefit

Bimodal Advantages

• Head shadow effect • Binaural squelch • Binaural redundancy • Localization

81

Benefits of Bimodal Fitting

• Improved localization • Improved hearing in quiet and
background noise

• Subjective benefit • Helps avoid auditory deprivation

Limitations of CI
• Listening in background noise • Music appreciation • Understanding tonal languages • Perceiving tone of voice • Identifying different talkers
… can bimodal hearing help?

My Research
Question: is bimodal hearing better than bilateral CI in listening situations that rely on pitch?

82

Limitations of CI

• Listening in background noise • Music appreciation • Perceiving tone of voice • Identifying different talkers
… can bimodal hearing help?

Sentences With Background Talker
• HINT sentences spoken by male • Background sentences spoken by
either female, male, or child

• Measure SRT: signal to noise ratio at
which listener scores 50% correct

HINT Results

83

Limitations of CI

• Listening in background noise • Music appreciation • Perceiving tone of voice • Identifying different talkers
… can bimodal hearing help?

Montreal Battery of Evaluation of Amusia (MBEA)

• Scale • Contour • Interval • Rhythm • Metric • Memory

MBEA Results
pitch timing

chance

= stat sig diff

84

Limitations of CI

• Listening in background noise • Music appreciation • Perceiving tone of voice • Identifying different talkers
… can bimodal hearing help?

Intonation Perception

Perception of Sarcasm
‘Changing pitchers was a smart move.’

• Genuine

• Sarcastic

85

Intonation Perception Results

= stat sig diff

Limitations of CI

• Listening in background noise • Music appreciation • Perceiving tone of voice • Identifying different talkers
… can bimodal hearing help?

Talker Identification

• Talker ID is dependent on
gender discrim

accurate pitch perception

• CI users can typically perform • Also important to recognize
voices within category

86

Talker ID

Talker ID Results

Limitations of CI

• Listening in background noise • Music appreciation • Perceiving tone of voice • Identifying different talkers
… can bimodal hearing help?

87

Results …

• Coming next year!

Conclusion

• Two is better than one

88

Simple Techniques for Evaluating the Dizzy Patient
Scott D.S. Eggers, MD Mayo Clinic Rochester, Minneosta
CP1120443-1

Outline
• Vestibular physiology review • Examination techniques with cases • Application to the vestibular and
audiology laboratory

The Labyrinth

Max Brödel archives, Johns Hopkins University

89

The Labyrinth

Vestibulo-ocular Reflex

Eye Movements and Semicircular Canals
The 6 extraocular muscles move eyes in the same planes as the 6 semicircular canals

http://schorlab.berkeley.edu/vilis/matching.htm on 4/8/04

90

Eye Movement Patterns From Individual Canal Stimulation

Leigh and Zee 2006

Bedside Exam
• Ocular motor testing
• Alignment, range, gaze-holding, saccades,
pursuit, convergence, VOR suppression

• Static vestibular imbalance
• Spontaneous nystagmus • Ocular tilt reaction with skew deviation • Dynamic vestibular function • Dynamic visual acuity • Head thrusts & occlusive ophthalmoscopy • Provocative maneuvers • Positional testing, headshaking, Valsalva,
noise, hyperventilation, mastoid vibration

Bedside Exam
• Ocular motor testing
• Alignment, range, gaze-holding, saccades,
pursuit, convergence, VOR suppression

• Static vestibular imbalance
• Spontaneous nystagmus • Ocular tilt reaction with skew deviation • Dynamic vestibular function • Dynamic visual acuity • Head thrusts & occlusive ophthalmoscopy • Provocative maneuvers • Positional testing, headshaking, Valsalva,
noise, hyperventilation, mastoid vibration

91

Rules of Spontaneous Peripheral Vestibular Nystagmus

• Brought out or enhanced by removal of
visual fixation

• Unidirectional, with pattern of nystagmus
reflecting the canals that are affected of the quick phases

• Most intense when looking in the direction • Gradually resolves due to peripheral
recovery or central compensation, but may persist slightly with removal of vision

Spontaneous Nystagmus: Static Canal-Ocular Imbalance

Courtesy of DS Zee. from Neurotology. Continuum: Lifelong Learning in Neurology, Vol. 2, Advanstar Communications: Cleveland, 1996.

Looking For Spontaneous Nystagmus
A Romberg test for the vestibular system Note nystagmus direction & differences with and without visual fixation

Occlusive Ophthalmoscopy

92

Spontaneous Nystagmus & Alexander’s Law
Acute left peripheral vestibular loss

Nystagmus is greater when looking toward the quick phases

Cerebellum & Gaze Holding
The vestibulocerebellum improves the performance of the leaky neural integrator via a positive feedback loop

Gaze-evoked nystagmus

Perfect
Leigh and Zee 2006

Gaze-evoked and Rebound Nystagmus in Cerebellar Degeneration

Gaze-evoked nystagmus

Rebound nystagmus

93

Alexander’s Law
• Brain disables the neural
integrator in acute vestibular imbalance, leading to gaze-evoked nystagmus
Acute left vestibular hypofunction
(right-beating nystagmus)

Net Slow Phase Velocity

• Thus, peripheral

nystagmus is greatest looking in direction of the quick phases where it adds to the gaze-evoked nystagmus of a leaky integrator phases minimizes or may abolish nystagmus

• Looking toward slow

Bedside Exam
• Ocular motor testing
• Alignment, range, gaze-holding, saccades,
pursuit, convergence, VOR suppression

• Static vestibular imbalance
• Spontaneous nystagmus • Ocular tilt reaction with skew deviation • Dynamic vestibular function • Dynamic visual acuity • Head thrusts & occlusive ophthalmoscopy • Provocative maneuvers • Positional testing, headshaking, Valsalva, noise,
hyperventilation, mastoid vibration

Ocular Tilt Reaction: A Static Otolith Imbalance
Ocular Counterroll Skew deviation (vertical ocular misalignment)

Tessa with acute left labyrinthine failure Th Brandt, Lancet 1999

Head Tilt

94

Ocular Tilt Reaction

Brodsky. Surv Ophthal 2006

Dynamic Vestibular Function

• We need a simple bedside test of

the function of each individual vestibular labyrinth / semicircular canal

Bedside Exam
• Ocular motor testing
• Alignment, range, gaze-holding, saccades,
pursuit, convergence, VOR suppression

• Static vestibular imbalance
• Spontaneous nystagmus • Ocular tilt reaction with skew deviation • Dynamic vestibular function • Dynamic visual acuity • Head thrusts & occlusive ophthalmoscopy • Provocative maneuvers • Positional testing, headshaking, Valsalva, noise,
hyperventilation, mastoid vibration

95

Normal “Doll’s Eyes” in Bilateral Vestibular Loss

This demonstrates vestibular loss only if in coma or also impaired smooth pursuit!

Head Thrust Sign (Impulse Test) in Left Labyrinthine Loss
Catch-up saccade to brief, high-velocity head rotation: a sign of peripheral vestibular loss Present because excitation causes a stronger nerve impulse than inhibition

Head Thrust Sign in Bilateral Vestibular Loss

96

Bedside Exam
• Ocular motor testing
• Alignment, range, gaze-holding, saccades,
pursuit, convergence, VOR suppression

• Static vestibular imbalance
• Spontaneous nystagmus • Ocular tilt reaction with skew deviation • Dynamic vestibular function • Dynamic visual acuity • Head thrusts & occlusive ophthalmoscopy • Provocative maneuvers • Positional testing, headshaking, Valsalva,
noise, hyperventilation, mastoid vibration

Dix-Hallpike Maneuver

Bedside Exam
• Ocular motor testing
• Alignment, range, gaze-holding, saccades,
pursuit, convergence, VOR suppression

• Static vestibular imbalance
• Spontaneous nystagmus • Ocular tilt reaction with skew deviation • Dynamic vestibular function • Dynamic visual acuity • Head thrusts & occlusive ophthalmoscopy • Provocative maneuvers • Positional testing, headshaking, Valsalva, noise,
hyperventilation, mastoid vibration

97

Headshaking Nystagmus
• Asymmetric
excitatory input from headshaking velocity storage mechanism as HSN

• Central

• Discharges

Bedside Exam
• Ocular motor testing
• Alignment, range, gaze-holding, saccades,
pursuit, convergence, VOR suppression

• Static vestibular imbalance
• Spontaneous nystagmus • Ocular tilt reaction with skew deviation • Dynamic vestibular function • Dynamic visual acuity • Head thrusts & occlusive ophthalmoscopy • Provocative maneuvers • Positional testing, headshaking, Valsalva, noise,
hyperventilation, mastoid vibration

Vibration-induced Nystagmus

• Patient

with left vestibular loss
Mastoid vibration produces a net excitation throughout the vestibular system & nystagmus rotational vectors aligning with the remaining intact semicircular canals

98

Bedside Exam
• Ocular motor testing
• Alignment, range, gaze-holding, saccades,
pursuit, convergence, VOR suppression

• Static vestibular imbalance
• Spontaneous nystagmus • Ocular tilt reaction with skew deviation • Dynamic vestibular function • Dynamic visual acuity • Head thrusts & occlusive ophthalmoscopy • Provocative maneuvers • Positional testing, headshaking, Valsalva, noise,
hyperventilation, mastoid vibration

Noise-induced Nystagmus (Tullio’s Phenomenon)
Patient with vertigo & oscillopsia induced by singing, straining, & sneezing
Vertical/torsional nystagmus aligning with left superior canal
Courtesy of Lloyd Minor & David Zee

Valsalva-induced Nystagmus

Courtesy of Lloyd Minor & David Zee

99

Superior Canal Dehiscence
Intact side Abnormal side
Lloyd Minor

Eye Movement Recording in SCD
Axis of eye rotation aligns with that expected from stimulation of the left superior semicircular canal

Minor, Solomon, Zinreich, Zee. Arch Otol HNS 1998

Physiologic Basis of Eye Movements in SCD

Minor, Solomon, Zinreich, Zee. Arch Otol HNS 1998

100

Air-Bone Gap in SCD
• “Third mobile
window” causes apparent conductive hearing loss by dissipating acoustic energy through the dehiscence conducted sounds to better than 0 dB HL hearing eyes move, pulsatile oscillopsia

• May amplify bone • Malleolus sign,

Songer and Rosowski 2005

Air-Bone Gap in SCD

Masked bone conduction thresholds to -10-20 dB
Streubel et al 2004

Vestibular Evoked Myogenic Potentials

• Short-latency • Sacculus to

relaxation potentials sternocleidomastoid vestibular nerve integrity ? larger amplitudes in SCD

• Tests inferior

• Lowered thresholds &

Colebatch 2001

101

Clues to Possible SCD
• Air-bone gap with apparent conductive hearing
loss, lateralizing Weber, but… responses

• Normal acoustic reflexes and intact VEMP • Should consider SCD rather than otosclerosis,
stapes fixation, or other middle ear causes conduction thresholds to -20 dB HL Hennebert’s sign

• Calibrate audiometer to measure bone • Check for Tullio’s phenomenon &

Bedside Exam
• Ocular motor testing
• Alignment, range, gaze-holding, saccades,
pursuit, convergence, VOR suppression

• Static vestibular imbalance
• Spontaneous nystagmus • Ocular tilt reaction with skew deviation • Dynamic vestibular function • Dynamic visual acuity • Head thrusts & occlusive ophthalmoscopy • Provocative maneuvers • Positional testing, headshaking, Valsalva, noise,
hyperventilation, mastoid vibration

Hyperventilation-induced Nystagmus

102

Left Vestibular Schwannoma
Hyperventilation improves nerve conduction through lesion

Bedside Exam
• Ocular motor testing
• Alignment, range, gaze-holding, saccades,
pursuit, convergence, VOR suppression

• Static vestibular imbalance
• Spontaneous nystagmus • Ocular tilt reaction with skew deviation • Dynamic vestibular function • Dynamic visual acuity • Head thrusts & occlusive ophthalmoscopy • Provocative maneuvers • Positional testing, headshaking, Valsalva, noise,
hyperventilation, mastoid vibration

Isolated Saccadic Palsy

103

Normal Smooth Pursuit

Optokinetic Testing
No OKN Quick Phases

Sinusoidal Rotary Chair
No Vestibular Quick Phases

104

VOR Intact

Summary
• Vestibular Physiology • Stimulation or inhibition of a single
SCC rotates the eyes around an axis perpendicular to the plane of the canal resolve from central compensation, but nystagmus may persist with removal of visual fixation

• Vertigo from a peripheral lesion may

Summary
• Ocular motor testing
• Alignment, range, gaze-holding, saccades,
pursuit, convergence, VOR suppression

• Static vestibular imbalance
• Spontaneous nystagmus • Ocular tilt reaction with skew deviation • Dynamic vestibular function • Dynamic visual acuity • Head thrusts & occlusive ophthalmoscopy • Provocative maneuvers • Positional testing, headshaking, Valsalva,
noise, hyperventilation, mastoid vibration

105

Bedside Exam
• Ocular motor testing
• Alignment, range, gaze-holding, saccades,
pursuit, convergence, VOR suppression

• Static vestibular imbalance
• Spontaneous nystagmus • Ocular tilt reaction with skew deviation • Dynamic vestibular function • Dynamic visual acuity • Head thrusts & occlusive ophthalmoscopy • Provocative maneuvers • Positional testing, headshaking, Valsalva,
noise, hyperventilation, mastoid vibration

Dix-Hallpike Maneuver

Otoconia in BPPV

106

Dix-Hallpike Maneuver: BPPV

Furman and Cass NEJM 1998

Benign Paroxysmal Positioning Vertigo

Slow phases

Canalith Repositioning Maneuver

John Epley
Furman and Cass NEJM 1998

107

New Frontiers in Otoprotective Agents
Kathleen C.M. Campbell, PhD Southern Illinois University Springfield, Illinois
CP1120443-1

Contact Information

• E-mail: Kcampbell@siumed.edu • For e-mails use “ototoxicity” in • Phone: (217) 545-7310 • Mail: PO Box 19629

subject line so I don’t delete it as spam

SIU School of Medicine Springfield, IL 62794-9629

108

Current Status of D-met Research
• FDA approved our IND 1/28/2005 for D-met
protection from radiation induced oral mucositis

• Clinical Trials at Johns Hopkins • Phase II clinical trials for cisplatin and

aminoglycoside otoprotection in progress in India. Looking for US patient populations protection

• In discussions with military for NIHL • More bench work also needed

Proposed Otoprotective Agents
• Sodium Thiosulfate
(STS)

• GSH, GSH ester • Fosfomycin • Diethydithiocarbamate (DDTC)

• • • •

WR2721 (Ethyol) Lipoic Acid Salicylate N-acetylcysteine (NAC) met)

• Ebselen • L-carnitine
(ALCAR)

• D-methionine (D-

Pre-clinical Trials with Dmethionine
Platinum Compound Studies

109

Methods
• 5 groups of 5 male Wistar rats each • Treated control group received 16
mg/kg CDDP infused over a 30 minute period saline only

• Untreated control group received • Experimental groups received either
75, 150 or 300 mg/kg D-met 30 minutes prior to 16 mg/kg CDDP

110

111

UNTREATED CONTROL

CISPLATIN TREATED

D-MET PROTECTED

112

UNTREATED CONTROL

CISPLATIN TREATED

D-MET PROTECTED

113

UNTREATED CONTROL

CISPLATIN TREATED

114

D-MET PROTECTED

Conclusions
• D-met can protect against CDDP• D-met partially protects against
CDDP-induced weight loss induced ABR threshold shift, OHC loss, and strial damage

• D-met provides nephroprotection • Patent coverage for neuroprotection,
GI protection and alopecia

Other Findings
• D-met can be administered directly to the
round window and still protect against systemic or topical cisplatin-induced ototoxicity induced ototoxicity induced ototoxicity

• D-met protects against carboplatin• D-met protects against aminoglycoside• Some patients receive all 3 drugs • D-met also can protect against NIHL

115

D-met Tumor Model Studies

• In vitro tumor model studies may not
be relevant to clinical model

• In vivo model for ovarian cancer did

not show anti-tumor interference (UCI Irvine) show anti-tumor interference (OHSU)

• In vivo model for lung cancer did not

Tumor Models
• Human ovarian cancer (OVCAR) grown as a
xenograft in athymic nude mice

• 10 animals per cell • CDDP given at 7.5 and 15 mg/kg, D-met 150
mg/kg

• High dose CDDP without D-met inhibited tumor
growth but shortened survival

• D-met increased survival with high dose CDDP
with no antitumor interference inhibition for low dose CDDP

• D-met did not change survival or tumor • D-met alone did not change tumor growth

D-methionine Does Not Interfere With Antitumor Activity of Cisplatin in Ovarian Cancer Xenograft Tumor Model
D o s e R e s p o n s e D a ta
S aline D -M et, 15 0 m g /k g c is P latin, 15 m g/k g c is P latin, 7.5 m g/k g c is P latin+ D -M et, 15+ 15 0 m g /k g c is P latin+ D -M et, 7.5+ 15 0 m g /k g

1000

Mean Tumor Burden (mg) + SE

100

30

35

40

45

50

55

60

D a ys P o s t T u m o r Im p la n t

116

Protection from Aminoglycoside Ototoxicity
Gentamicin: Sha and Schacht 2000 Amikacin: Klemens et al 2003 Patent Campbell/SIU

Sha and Schacht 2000
• Study 1: 6 groups pigmented male guinea
pigs

• • • • • •

1) 120 mg gentamicin/kg 19 days 2) 100 mg/kg histidine combined w/gent 3) 200 mg/kg D-met combined w/gent 4) Saline only 5) D-met only 6) Histidine only

Effects of once-daily treatment with histidine or D-methionine on gentamicin-induced threshold shifts. Animals were treated and ABR thresholds determined as described in Section 2. Values are means ± S.E.M. (n = 6) of threshold shifts at 6.5 weeks. Saline: controls receiving saline; Gm: gentamicin; Gm+his, Gm+met: groups receiving gentamicin in combination with histidine or methionine, respectively. All gentamicin-induced threshold shifts are significant. * Differs from gentamicin alone, 0.1 > P > 0.05. ** Differs from gentamicin alone, P < 0.05. (Sha and Schacht 2000)

117

Sha and Schacht 2000

• Study 2: male pigmented guinea pigs • 19 day administration • 200 mg/kg d-met twice daily • First dose combined with 120mg
gentamicin s.c. hours later

• Second dose of D-met injected ip 7

Effect of twice-daily treatment with D-methionine on gentamicin-induced threshold shifts. ABR thresholds were determined from 0 to 6.5 weeks. Values are means±S.D. (n=6). Open circles (yellow), controls; filled circles (red), gentamicin alone; open squares (blue), gentamicin plus Dmethionine. Gentamicin increased thresholds at 3.5 weeks and later (P < 0.05). D-methionine attenuated these threshold shifts at 3 kHz at 3.5 and 4.5 weeks (0. 1 > P < 0.05). (Sha and Schacht 2000)

Effect of twice-daily treatment with D-methionine on gentamicin-induced threshold shifts. ABR thresholds were determined from 0 to 6.5 weeks. Values are means±S.D. (n=6). Open circles (yellow), controls; filled circles (red), gentamicin alone; open squares (blue), gentamicin plus D-methionine. Gentamicin increased thresholds at 3.5 weeks and later (P < 0.05). D-methionine attenuated these threshold shifts at 9 kHz at 3.5 weeks and later (P<0.05). (Sha and Schacht 2000)

118

Effect of twice-daily treatment with D-methionine on gentamicin-induced threshold shifts. ABR thresholds were determined from 0 to 6.5 weeks. Values are means±S.D. (n=6). Open circles (yellow), controls; filled circles (red), gentamicin alone; open squares (blue), gentamicin plus D-methionine. Gentamicin increased thresholds at 3.5 weeks and later (P < 0.05). D-methionine attenuated these threshold shifts at 18 kHz at 3.5 weeks and later (P < 0.05). (Sha and Schacht 2000)

More Studies Needed
• Can we use higher dosing levels or
more doses per day to improve otoprotection

• Studies thus far suggest no interference
with the antimicrobial action of gentamicin or amikacin, but further study needed for other aminoglycosides or other antibiotics given in combination?

• Can we protect against tobramycin,

kanamycin, and neomycin ototoxicity?

Otoprotectants for NIHL

119

Dietary Supplements
• Several NIHL otoprotective agents are also
micronutrients:

• • • • •

Mg: fish, almonds, spinach, shrimp, bran D-met: cheese, yogurt NAC: brussel sprouts Resveratrol: red wine Selenium: Brazil nuts, N. Dak and S.Dak grown foods, prime component of ebselen

• Alcohol: 2-4 drinks per day

Antioxidant Therapies Approaching Clinical Trials

• Ebselen • N-Acetylcysteine (NAC) • D-Methionine (D-MET) • L-Carnitine (ALCAR) • Salicylate (as concomitant agent)
Agents have good safety profile and oral bioavailability

Kopke et al 2000, 2002
• Chinchilla model • 105 dB SPL noise band centered at
4kHz

• D-met or ALCAR administered at

200mg/kg ip, NAC at 325mg/kg plus salicylate hours prior to noise and 1 hour prior to the noise and then twice per day for 2 days following noise exposure

• Administered every12 hours starting 48

120

N-acetylcysteine (NAC): Putative Mechanisms

• L-NAC is a free radical scavenger • Neuroprotectant • GSH precursor: provides cystolic
but not mitochondrial GSH

• Can prevent JNK activation

121

A Catalyst for Hearing Loss Treatment
Eric D. Lynch, PhD
4010 Stone Way N Suite 120 Seattle, WA

Ebselen

Ebselen (SPI-1005)—How Does it Work?
• Small molecule mimic of glutathione
peroxidase (GPx) • Glutathione Pathway—ROS/RNS neutralization • GPx catalytic activity

Otoprotection Across Frequencies
4 mg/kg SPI-1005, ABR at 9 wks post noise, n=8 (3 & 14d), n=6 (7d), SEM shown
Continuous 4 hr noise exposure 4-16 kHz noise at 113 dBSPL

ABR Threshold Shift (dB)

50 40 30 20 10 0 4 8 16 32 Stimulus (kHz)

Control 3 day 7 day 14 day
p<0.05 p<0.01 p<0.001

122

Cytocochleogram Analysis
3 wks post noise

D-methionine: Putative Mechanisms
• Unlike most amino acids, methionine is • Methionine can provide cysteine, a
reversibly oxidized (Vogt 1995) and thus may serve as a free radical scavenger precursor for glutathione (GSH) synthesis and can prevent the efflux of GSH from injured cell

• Can increase mitochondrial GSH levels • May protect antioxidant enzyme levels • D-met well tolerated even at high dosages

123

Met HC Protection

124

D-met Post-Noise Rescue Mitchell, Meech, Campbell

• D-met can be administered 1 hour
after noise exposure and provide protection from permanent NIHL TTS but only PTS

• Does not provide significant against • Methods: 6 hour: 105dB SPL 4kHz
octave band noise, 200 mg/kg D-met 1 hour after exposure and 2 days BID protection at 2, 4, 6 & 8 kHz

• With 10 animals per group, significant

D-met Rescue From NIHL
D-Met Rescue From Noise-Induced Hearing Loss
A R Threshold Shift From AB Threshold Shift From BR B BaselineTo 21 DaysPost aseline To 21 D ays Post 30 30 25 25 20 20 15 15 10 10 5 5 0 0 2kHz 2kHz 4kHz 4kHz 6kHz 6kHz 8kHz 8kHz Control Control Treated Treated

How Long Can D-met be Delayed and Still Protect From NIHL?

• • • •

Study in progress: Campbell & Meech 105 dB SPL 4kHz NB for 6 hours Chinchillas Laniger D-met initially started at either 1, 3, 5 or 7 hours after noise cessation with 4 additional BID doses 12 hours apart and saline control, 3 per group at 7 hours following slides

• 5 animals per group for 1,3,5 hour groups • ABR thresholds at 21 days presented in

125

21 DAY POST NOISE EXPOSURE 2000 Hz
30 A B R TH R ES H O LD S H IFT 25 20 15 10 5 0
Saline Control N=5 D-Met 1 hour post N=5 D-Met 3 hour post N=5 D-Met 5 hour post N=5 D-Met 7 hour post N=3

0.081

0.081

*.039

GROUPS

21 DAY POST NOISE EXPOSURE 4000 Hz
35 A B R TH R E S H O LD S H IFT 30 25 20 15 10 5 0
Saline Control N=5 D-Met 1 hour post N=5 D-Met 3 hour post N=5 D-Met 5 hour post N=5 D-Met 7 hour post N=3

*.015

*.032

.065

.104

GROUPS

21 DAY POST NOISE EXPOSURE 6000 Hz
16 ABR THRESHOLD SHIFT 14 12 10 8 6 4 2 0 -2
Saline Control N=5 D-Met 1 hour post N=5 D-Met 3 hour post N=5 D-Met 5 hour post N=5 D-Met 7 hour post N=3

GROUPS

126

21 DAY POST NOISE EXPOSURE 8000 Hz
25 20 15 10 5 0 -5
GROUPS 1.00

ABR THRESHOLD SHIFT

Saline Control N=5

D-Met 1 hr post N=5

D-Met 3 hr post N=5

D-Met 5 hr post N=5

D-Met 7 hr post N=3

Next Step?
• Clinical trials to compare efficacy and
side effects for cisplatin, carboplatin, aminoglycoside and noise otoprotection and for radiation induced oral mucositis

• More work on mechanisms • Hopefully more than one agent will be
FDA approved for all of these applications in the not too distant future

Collaborators SIU School of Medicine

• Kathleen Campbell, PhD • Leonard Rybak,MD, PhD • Robert Meech, MA • Larry Hughes, PhD • Robert Helfert, PhD • Kurt Korver MD • Deb Larsen BA

127

SIU Student Collaborators
• • • • • • • •
James Klemens David Donnersberger Jill Young Tom Kelly David Kluge Dianna Mitchell Todd Gerberi Mike Berry

• • • • • • • •

Sohol Patel Katen Amin Laura Adamson Brian Spring Sarah Kocher Mike Fritz Tiffany Oldfather Deb Larsen

Collaborators: Navy Medical Center, San Diego

• Richard Kopke, MD • John Coleman, PhD • Ronald Jackson, PhD • Xinyan Huang, MD, PhD

OHSU Collaborators Lung Tumor Model

• Ed Neuwelt, MD • Leslie Muldoon, PhD • Nancy Doolittle, PhD

128

UC Irvine Collaborators Ovarian Tumor Model

• Noelle Gillette Cloven, MD • Alessandra Re, MD • Michael McHale, MD • G. Scott Rose, MD • Robert A. Burger, MD • Philip DiSaia, MD • H.Y. Fan, PhD

Discussion and Questions

129


				
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