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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
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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 • 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 • No active middle ear disease • No cochlear nerve or auditory pathway lesions • Cochlear anatomy allows implantation • Able to tolerate surgery • Enrolled in an educational program that supports listening and speaking for communication • Highly motivated with appropriate expectations (family and child)
A Team Decision • 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 • 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 • Surgically implanted under the skin • Electronics package (receiver-stimulator) with magnet • Electrode array placed inside the cochlea • External Device • 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 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 • Advanced Bionics • Cochlear • MED-EL
Advanced Bionics (www.cochlearimplant.com) • Clarion and Bionic Ear • HiRes 90K internal • Platinum Series Processor • Auria BTE Processor
Cochlear (www.cochlear.com) • Nucleus • Contour and Contour Advance internals • SPrint processor • ESPrit 3G BTE Processor
MED-EL (www.medel.com) • Combi 40+ internal • Tempo+ BTE processor with 5 modular options • CIS-PRO+ body processor
Common Features of CI Sound Processors • Power Switch • On-Off • Battery • Charge Meter • Display • Lights • Program Control • Selects Program or MAP loaded into the processor • 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 • Volume Control • Adjusts level of loud sounds within a program • Sensitivity Control • Determines if distant or very soft sounds will be processed
Know the Child and the Device • Know which CI the child is using • Know which settings have been recommended for the external processor • Observe current settings • Change to the recommended settings if needed • Verify the system is working prior to therapy • 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 • Talk to parents about the child and the device • 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) • Advanced Bionics 1-800-678-2575 • Cochlear (Customer Service) 1-877-883-3101 • MED-EL 1-888-633-3524
CI Programming Basics • Audiologists select the parameters for each listening program • 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 • Threshold assessment • 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 • 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 • Due to more frequent contact, the therapist may know the child better • 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 • Offer to directly assist the audiologist in CI programming • May be billable as “consultation with others” if preauthorized • Offer to work on tasks in therapy that will facilitate CI programming • 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 • 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