Technology Updates
Sunday March 7, 2004
8:00 and repeated at 8:30
- New ABR Procedures to Screen for Small Acoustic
Tumors and Meniere's Disease
as Implemented on the Bio-logic Navigator Pro System
Manuel Don, Ph.D.
House Ear Institute, Los Angeles, CA
Gabriel Raviv, Ph.D.
Bio-logic Systems Corp., Mundelein, IL
- Improving the Individualization of Prescriptive
Fittings
Curtis N. Williams, M.S.
Oticon, Inc., Somerset, NJ
- An Algorithm for Effective Feedback Cancellation
with Minimized Artifacts
Chris Conger, MSEE
Robert Fretz, MSEE
Resistance Technology, Inc., Arden Hills, MN
- Advancing the Science of Noise Reduction
Steve Armstrong
Gennum Corporation, Burlington, ON Canada
9:00 and repeated at 9:30
- Comparisons of Two Types of Group Delay Measurements
on Digital Hearing Aids
George J. Frye
Frye Electronics, Inc.
Tigard, OR
- Clinical Evaluation of the Dynamic Algorithms in
Axent II
Laurel Olson, M.A.
Starkey Laboratories, Eden Prairie, MN
- Hearing Aid Myths and Fables
Michael Nilsson, Ph.D.
SONIC Innovations, Salt Lake City, UT
- A New Style Hearing Aid: The Post-Auricle Canal
(PAC)
Wayne J. Staab, Ph.D.
For: SeboTek Hearing Systems, Tulsa, OK
10:00 and repeated at 10:30
- The Nucleus Cochlear Implant Systems: Bringing
Hearing to Life
Christine Menapace, MA,
Cochlear Americas, Englewood, CO
- Research Findings with Open Hearing Aid Fittings
Laurel A. Christensen, Ph.D.
GN ReSound Group, Chicago, IL
- Applications for Adaptive Directional Microphone
Technology
David A. Fabry, Ph.D.
Phonak Hearing Systems, Warrenville, IL
- New Technology from Everest Biomedical
Gerald R. Popelka, Ph.D.
Everest Biomedical Instruments, St. Louis, MO
11:00 and repeated at 11:30
8:00 and repeated
at 8:30
New ABR Procedures to Screen for Small Acoustic
Tumors and Meniere's Disease
as Implemented on the Bio-logic Navigator Pro System
Manuel Don, Ph.D.
House Ear Institute, Los Angeles, CA
Gabriel Raviv, Ph.D.
Bio-logic Systems Corp., Mundelein, IL
This presentation will briefly review the fundamental principles and
application of two new ABR techniques. One, the Stacked ABR, is used
to screen for small (<=1 cm) acoustic tumors (vestibular Schwannomas)
in the internal auditory canal. This technique overcomes the failure
of standard ABR measures in detecting small acoustic tumors. The other
technique is used to screen for Meniere's disease in an individual
patient and involves measures of ABRs to clicks presented alone and
in the presence of high-pass masking noise. This latter technique clearly
distinguishes individual patients with Meniere's disease/cochlear hydrops.
Sensitivity and specificity data for both of these techniques are also
presented. The availability and implementation of these new ABR techniques
on the Bio-logic Navigator Pro system will be discussed. Software implementation
focuses on automating the test procedure and required calculations
and providing computer-assisted data analysis to facilitate interpretation
of the results.
Improving the Individualization of Prescriptive
Fittings
Curtis N. Williams, M.S.
Oticon, Inc., Somerset, NJ
It is widely assumed that different patients have different amplification
needs, yet prescriptive fitting rationales have traditionally used
only audiometric information (HTLs & UCLs) as input. As advanced
digital hearing aids provide increasingly complex functionalities,
other patient variables such as communication needs, age, etiology
and previous amplification experience become relevant to the fitting
Within the simple bounds of wide dynamic range compression (WDRC),
adjustable parameters exist in modern hearing aids such as attack time,
release time and threshold of compression, for which little guidance
is provided. Coupled with an increasing array of advanced functionality
such as adaptive directionality and noise management circuitry being
offered, the challenge becomes even more complex.
Clinical data is emerging to help us manage the setting and adjustment
of these additional parameters. This new clinical data will be discussed,
and specific strategies to incorporate this emerging knowledge base
into clinical practice will be shared.
An Algorithm for Effective Feedback Cancellation
with Minimized Artifacts
Chris Conger, MSEE
Robert Fretz, MSEE
Resistance Technology, Inc., Arden Hills, MN
Recently, RTI introduced the Digital-ONE"! 4-channel Amplifier
featuring the unique Automatic Feedback Reduction System. The presenters
will discuss the development of this feedback cancellation system,
which is based on the classical method of adaptive filtering using
the least-mean-squared criterion. Explanation of the technique will
be given, and the resulting stability improvement will be demonstrated
both visually and audibly. The presenters will then discuss the problem
of auto-correlated inputs causing audible artifacts and mis-adaptation.
A patent-pending solution to this problem will be demonstrated using
an audio presentation.
Advancing the Science of Noise Reduction
Steve Armstrong
Gennum Corporation, Burlington, ON Canada
The hearing impaired frequently find listening
in noisy environments challenging. Restoring audibility through amplification
alone isn't sufficient to completely overcome this problem. While many
advances have been made, most signal processing strategies result in
undesirable artifacts that can detract from user satisfaction.
A new refinement to the basic spectral subtraction technique has
shown to significantly reduce the distortion common in most of today's
offerings. The addition of a psychoacoustic model to the adaptation
algorithm modifies the way gains are changed, and is at the heart of
the improvement.
Results of a study to understand the amount of subjective noise reduction
indicate a 9-dB improvement in noise, with negative comments concerning
distortion. This presentation will also show the results of an objective
measurement technique and discuss possible future work.
9:00 and repeated at 9:30
Comparisons of Two Types of Group Delay Measurements
on Digital Hearing Aids
George J. Frye
Frye Electronics, Inc.
Tigard, OR
An impulse response test of group delay has been available in the
FONIX 6500CX instrument for a number of years. The impulse contains
a very wide band of frequencies. The question has been raised if group
delay may be a function of frequency. A test using a series of wavelet
like waveforms with energy centered on standard 1/3 octave frequencies
and with each test waveform adjusted to have a bandwidth of 1/3 octave
was created and used to check a limited number of hearing aids. With
one exception the results of the two types of tests were compatible.
The exception gave result differences that are probably not clinically
significant.
Results from impulse response group delay tests made with the FONIX
6500CX can be accepted as reliable.
Clinical Evaluation of the Dynamic Algorithms in
Axent II
Laurel Olson, M.A.
Starkey Laboratories, Eden Prairie, MN
Backed by the commitment to implement only those technologies that
are proven effective, Starkey continues to focus on signal processing
schemes that provide true benefits for people with hearing loss. In
accordance with this, two new algorithms have been developed for Axent
II-Starkey's flagship digital product.
The first algorithm, dynamic directionality (or auto on/off) allows
the hearing aid to automatically switch between omnidirectional and
directional mode depending on the listening environment. Recent research
studies have defined specific environments where omni directional and
directional modes are beneficial. Our clinical studies have focused
on implementing an automatic directional system that takes this information
into account.
The second algorithm is a modification of the feedback cancellation
feature that was implemented on Axent I. This modification of the algorithm
has been developed to minimize the need to perform an initialization
at the beginning of a hearing aid fitting and to minimize audible artifacts
known as entrainment.
Clinical validation results substantiating patient benefit as well
as defining the parameter sets for both of these algorithms will be
discussed. As with any adaptive process, there are advantages and disadvantages;
these will also be discussed.
Hearing Aid Myths and Fables
Michael Nilsson, Ph.D.
SONIC Innovations, Salt Lake City, UT
A perusal of
current advertisements, marketing campaigns, and industry articles
express a wide range of opinions about what hearing aids should do,
what hearing aids currently are capable of, and why hearing care
professionals should choose one type of hearing aid over another.
The presentation will include some of the current hearing aid myths
and fables accepted as truth, and present data to support the author's
opinions about hearing aid design and performance. The participants
should leave this presentation with a better understand of
the difference between research conclusions and marketing messages,
and some minimum expectations of what makes a good hearing aid.
A New Style Hearing Aid: The Post-Auricle Canal
(PAC)
Wayne J. Staab, Ph.D.
For: SeboTek Hearing Systems, Tulsa, OK
A new style digital hearing aid, the PAC
(post-auricular-canal) provides substantial benefits to traditional
hearing aid fittings by its physical design in addition to its programmable
features. The unique style change results in a same-session fit instrument
utilizing the acoustical advantages of deep canal technology with the
receiver placed comfortably and securely in the bony structure via
its encasement in various sized soft fitting tips - eliminating the
need for a custom earmold. This system is essentially invisible cosmetically
and features a modular design to facilitate fitting, inventory control,
and service. Patients respond favorably to the same-session fit and
evaluation of performance, the elimination of the need for an ear impression,
satisfaction with the reduction of the occlusion effect, and that it
meets the amplification requirements of a very high percentage of hearing
losses. The presentation will be supported by research results and
clinical information.
10:00 and repeated at 10:30
The Nucleus Cochlear Implant Systems: Bringing Hearing
to Life
Christine Menapace, MA,
Cochlear Americas, Englewood, CO
This presentation provides an update on the unrivaled technology offered
by Cochlear and will describe technical characteristics of innovative
products that are studied. Current areas of clinical study and prospective
issues will also be addressed. Advances are currently focused on streamlined
programming optimization, electrode array design, and hybrid CI devices.
1. Recent innovations and current clinical focus areas include:
2. RP8: Cochlear's new research platform (includes advanced speech
coding capabilities and NRT V4) will be discussed and the associated
preliminary data reviewed.
3. Contour with Advance and Insertion Tool: An enhancement to the
Contour electrode array and the associated surgical technique (Advance
Off-Stylet) and insertion tool will be provided and preliminary surgical/clinical
data reviewed.
4. Hybrid CI: A new type of electrode array has been designed to stimulate
the high-frequency basal region of the cochlea while maintaining useful
acoustical hearing in the low-frequency apical region. Preliminary
data will be discussed.
5. Streamlined Programming Study: Study investigating the use of three
new programming techniques.
Research Findings with Open Hearing Aid Fittings
Laurel A. Christensen, Ph.D.
GN ReSound Group, Chicago, IL
Patients with high frequency hearing loss
want small, comfortable hearing instruments with natural sound quality
and without annoying feedback. It has been hard to fill both of these
requests at the same time using analog technology. Digital technology,
however, has allowed for the development of hearing aids that can deliver
on these requests simultaneously. First, the development of feedback
management systems has allowed more high frequency gain without feedback.
In addition, while large vents often caused feedback for patients with
high frequency hearing loss using analog hearing instruments, digital
feedback management has allowed for more "open" fittings. This session
will overview the research results of open hearing aid fittings including
measures of occlusion and feedback.
Applications for Adaptive Directional Microphone
Technology
David A. Fabry, Ph.D.
Phonak Hearing Systems, Warrenville, IL
Review of the MarkeTrak survey data reveal
that directional microphone technology provides the greatest impact
on hearing aid user satisfaction and benefit. This has resulted in
a significant increase in use of fixed-array directional microphones
in this US, but really reflects the underlying importance of preserving/enhancing
signal-to-noise ratiofor hearing aid users. Recently, the trend has
been toward adaptive directionality, which may incorporate adaptive
program switching and/or adaptive polar plots in hearing aids that
employ digital signal processing. The focus of this session will be
to evaluate the empirical support of this technology to provide improved
signal-to-noise ratio and user satisfaction and benefit. The data suggest
that adaptive directional microphones provide significant benefit,
when compared to fixed microphone array systems, when there are one
or two noise sources, but that the difference decreases as the background
noise becomes more diffuse. Future strategies incorporating ìauditory
scene analysisî and FM technology will also be discussed.
New Technology from Everest Biomedical
Gerald R. Popelka, Ph.D.
Everest Biomedical Instruments, St. Louis, MO
Everest Biomedical Instruments, a leader
of innovative and advanced biomedical devices, created AUDIOscreener,
the world's first complete solution to Universal Newborn Hearing Screening.
New features for this self-contained, battery-operated handheld device
will be presented along with two entirely new technologies. The first
addresses hyperbilirubinemia, a re-emerging problem in the neonatal
population. Though the incidence of the end stage of this condition,
kernicterus, was essentially eliminated a decade ago, over 125 new
cases (virtually all of whom are hearing impaired) have appeared because
of early hospital discharge practices and relaxed intervention standards.
Our new technology enhances non-invasive detection of this condition
and can be a useful complement to a neonatal hearing screening program.
The second new technology involves brain function monitoring during
anesthesia. Currently most surgical procedures do not include any brain
function monitoring and those that do only measure limited portions
of the brain. Either situation can result in imprecise control of anesthetic
agents. Insufficient anesthetic level can result in patient recall
of the surgery while excess anesthetic level can produce poorer recovery.
Our new technology allows more complete monitoring of brain function
both during and after anesthesia and can be a useful complement to
all procedures that involve anesthesia and other procedures such as
intraoperative monitoring.
11:00 and repeated at 11:30
Bionics Technology:
Next
Generation Processing for Current and Future Implant Users.
Edward Overstreet, Ph.D.
Advanced Bionics Corporation, Sylmar, CA
The CII and HiRes 90k systems are the only approved implantable devices
implementing a wide input dynamic range (82 dB), 12-bit analog-to-digital
conversion, and a 70 kHz input sampling rate. In addition, the system
has unprecedented stimulation-output flexibility with the ability to
apply advanced neuro-modulation techniques in order to maximize the
effectiveness of information transfer to the nerve. This output flexibility
is made possible by 16 fully independent current sources, and the temporal
precision to deliver extremely high rate stimulation in both simultaneous
and non-simultaneous modes. System capability is not limited when using
ear-level vs. body-worn processors and the majority of users, with
either body-worn or ear-level processors, have experienced improved
performance with first-generation HiResÇ processing compared
to conventional strategies. The next generation of HiRes processing
will extend spatial/spectral resolution to enable finely-tuned customized
fittings for each individual user. Improved spectral resolution is
accomplished through the use of precision-weighted current delivered
through simultaneously activated sources. In contrast to fixed position
or shorted-pair stimulation methods, the new HiRes technique can generate
controlled, nearly continuous stimulation patterns (as well as pitch-percepts)
along the length of the cochlear duct. In this presentation, inter-electrode
pitch-percept resolution data from CII and HiRes 90K users will demonstrate
that greater spatial resolution is possible with the ability to steer
current through simultaneous electrode activation. In addition, preliminary
patient results will show that this additional resolution can yield
near perfect melody recognition, even in the absence of rhythmic cues.
Siemens Digital Update
Thomas A. Powers, Ph.D.
Siemens Hearing Instruments, Piscataway, NJ
The latest market data indicates that digital
products command an increasing larger portion of the total market.
Product features should reflect an increase in technology level as
the cost to the user increases. This presentation will present a technology
pyramid that can be used by the audiologist and the consumer to differentiate
technology feature that are relevant to the users lifestyle and audiometric
requirements.
Returning to Bridge Tournaments and Restaurants
with a 20 dB SNR Loss
Mead C. Killion, Ph.D.
Frank Dunn
Viorel Drambarean
Andy Haapapuro
Etymotic Research
Elk Grove Village, IL
Older persons with a severe hearing loss
often a) stop going out to restaurants with family and friends, b)
can no longer partake in bridge tournaments, and c) decline -- in
advanced cases -- to come down to dinner in their retirement homes.
When lack of audibility is the primary problem, simply providing
hearing aids often brings such persons back to life. But an estimated
20% of all hearing aid wearers have SNR loss exceeding 10 dB, for
which non-directional hearing aids provide minimal help. We have
developed a "Companion Mic" system to improve the SNR at
the listener's ear by approximately 20 dB. In operation, the listener
clips a small "bug" microphone containing radio transmitters
onto the clothing of one to three of his or her companions, effectively
moving the listener's ears to within inches of the talker's mouth.
With the use of directional microphones, the result is a 25-dB increase
in SNR compared to the sound at the listener's ear. We believe this
is the first system that can practically
restore its users to the enjoyment of multiple companions in noisy
social situations.
Technology and Patient Needs: Let's Talk!
Rose A. Bongiovanni, AuD
Hearing Instrument Consultants Representing
Widex Hearing Aid Company
Costa Mesa, CA
Hearing aid technology has seen significant improvements in the recent
past. Yet as clinicians we still sometimes wonder "did my re-programming
actually change anything?" or "are those 2 microphones really working?" etc.
This session will explore the many new tools available on Widex Compass
software and how it integrates with Noah 3 and Noah Link to assist
you in simplifying your hearing aid fitting and fine tuning process.
