Download Introduction to Cochlear Implants for EI Service Providers

Introduction to Cochlear
Implants for EI Service
Providers
Roxanne J. Aaron, MA, CCC-A, FAAA
The Moog Center for Deaf Education
March 2005
Introduction

Hearing Loss Identified at Birth

Hearing Aids Fitted by age 3 to 6 months

Infants with Profound Hearing Loss Can Receive
Cochlear Implants by age 12 months

Increased Caseloads of Young Children with CI
What is a Cochlear Implant?
A surgically implanted medical device that
bypasses the damaged part of the inner ear to
electrically stimulate the remaining neural fibers
of the auditory nerve
Electrical current stimulates the remaining
auditory nerve fibers in the damaged inner ear to
generate sensations of hearing
What are the potential benefits of CI?

Access to sound
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Environmental sounds
Speech sounds
High frequency sounds
Soft sounds
Development of
speech recognition
and speech
communication
Who Can Get a Cochlear Implant?

Adults and children with severe to profound
sensorineural hearing loss

Est. >90,000 recipients worldwide
Pediatric Candidacy Criteria

12 months old or older

Profound Sensorineural Hearing Loss; (Severe to
Profound Sensorineural Hearing Loss if > 2 years
old for Cochlear device)

Limited benefit from hearing aids

Open-Set Speech Perception (e.g.. MLNT; LNT)
<20% Advanced Bionics and MED-EL, <30%
Cochlear
Pediatric Candidacy Criteria

No medical contraindications
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No active middle ear disease
No cochlear nerve or auditory pathway lesions
Cochlear anatomy allows implantation
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Able to tolerate surgery
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Enrolled in an educational program that supports
listening and speaking for communication
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Highly motivated with appropriate expectations
(family and child)
A Team Decision
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ENT Specialist
CI Surgeon
Audiologist
Speech/Language
Pathologist
Educator of the
Hearing Impaired
Child Psychologist
Social Worker
Parents
The Process of Obtaining a Cochlear
Implant
1. Hearing loss identification/diagnosis
2. Hearing aid trial (3-6 months)
3. Audiologic candidacy evaluation
4. Medical candidacy evaluation
5. Other evaluations (speech-language,
educational, psychological, etc.)
The Process of Obtaining a Cochlear
Implant
6. Team meeting
7. Surgery
8. Initial stimulation (a few weeks after surgery)
9. Ongoing CI programming (1 week, 1 month, 2
months, etc.)
10.Verification of performance with CI
The Process of Obtaining a Cochlear
Implant

CI Surgery


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A 2 to 4 hour procedure completed under
general anesthesia
The internal device is placed under the skin
behind the ear into a well created in the
mastoid bone
The electrode array is inserted into the cochlea
Cochlear Implant Components

Internal Device
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Surgically implanted under
the skin
Electronics package
(receiver-stimulator) with
magnet
Electrode array placed
inside the cochlea
External Device
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Worn on the body or at
ear level
Sound/speech processor
Microphone
Coil with magnet
Cochlear Implant Components

The external components of the CI system pick
up sounds, analyze them, and convert them into
an electrical signal that is sent to the internal
device located under the skin

Internal and external components are held close
to each other by a pair of magnets and
communicate via transcutaneous transmission of
a radio-frequency signal
Cochlear Implant Components

The internal device
decodes the signal and
sends electrical current to
each electrode

When the electrodes
stimulate the nerve fibers
of the auditory nerve, the
signal is received by the
brain and interpreted as
sound
Cochlear Implant Components
Cochlear Implant Companies

Devices from 3 manufacturers are FDA
approved for implantation in children

Each company has their own internal and
external components that are only
compatible with each other
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Advanced Bionics
Cochlear
MED-EL
Advanced Bionics (www.cochlearimplant.com)

Clarion and Bionic Ear

HiRes 90K internal

Platinum Series
Processor
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Auria BTE Processor
Cochlear
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Nucleus
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Contour and Contour
Advance internals
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SPrint processor
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ESPrit 3G BTE Processor
(www.cochlear.com)
MED-EL
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Combi 40+ internal
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Tempo+ BTE
processor with 5
modular options
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CIS-PRO+ body
processor
(www.medel.com)
Common Features of CI Sound
Processors
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Power Switch
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On-Off
Battery
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Charge Meter
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Display
Lights
Program Control
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Selects Program or MAP loaded into the processor
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Individual programs may have differing parameters such as
speech encoder strategy, rate of stimulation, pulse width
Individual programs have different electrical dynamic ranges for
each electrode which affect the perception of soft, average, and
loud sounds
Common Features of CI Sound
Processors
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Volume Control
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Adjusts level of loud
sounds within a
program
Sensitivity Control
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Determines if distant or
very soft sounds will be
processed
Know the Child and the Device
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Know which CI the child is using
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Know which settings have been recommended for the
external processor
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Observe current settings
Change to the recommended settings if needed
Verify the system is working prior to therapy
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Are the appropriate lights or displays working?
Does child look up or alert to sound?
Does child localize to sound?
Can the child participate in a Ling or word sound check?
Use monitor earphones
Know the Child and the Device

Talk to the CI audiologist about child's status, the
device, and the recommended settings
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Talk to parents about the child and the device
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Does the child use the device during all waking hours?
Are the parents comfortable with maintaining and
troubleshooting the device?
Request support materials from the CI company
(Educator Guides, Teacher Guides, Troubleshooting Guides, Videos)
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Advanced Bionics
Cochlear (Customer Service)
MED-EL
1-800-678-2575
1-877-883-3101
1-888-633-3524
CI Programming Basics
 Audiologists
select the parameters
for each listening program
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Speech encoder strategy
Stimulation rate
Number of electrodes stimulated, etc.
 Audiologists
work with each child to
set the program(s) within the CI
sound processor
CI Programming Basics
 The
child participates in tasks to help
set the minimum and maximum
amount of electrical current required
for each electrode
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Threshold assessment
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Behavioral observation
Conditioned response (VRA, CPA)
Loudness scaling/balancing
Electrophysiological measures (NRT, NRI,
ESRT)
CI Programming Basics

The settings derived during the CI programming
session form a listening program or MAP that is
loaded into the sound processor
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The listening program or MAP contains
information about the amount of electrical
current required by the child for hearing

CI programming is an ongoing process designed
to satisfy the child’s need for electrical
stimulation to optimize the perception of speech
EI Therapists and CI Programming

EI therapists can assist the audiologist in
CI programming directly or indirectly
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Due to more frequent contact, the therapist
may know the child better
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What toys does the child like or dislike?
What motivates the child?
Under what conditions does the child work best?
How does the child behave when tired or bored with
a task?
EI Therapists and CI Programming
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Offer to directly assist the audiologist in CI
programming
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May be billable as “consultation with others” if
preauthorized
Offer to work on tasks in therapy that will
facilitate CI programming
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Auditory detection tasks
Concepts such as “big” vs. “little” to assist with
loudness scaling
EI Therapists and CI Programming

Give feedback to the audiologist about
how the child is responding to sound
during therapy
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What sounds can child detect?
Are any sounds uncomfortable?
Keep the audiologist informed about the
child’s progress in learning to
communicate
Acknowledgements
Special thanks to the cochlear implant
manufacturers for the images and support
materials used for this presentation
Advanced Bionics
Cochlear
MED-EL
Thank You