1.05 - Cochlear Implants Flashcards
When was the first work on hearing implants stopped? Why?
1959
Funding issues
When was the first deaf person implanted? By whom? Where?
1957
Djourno & Eyries
France
Who was William House? When was his big year?
First person to be implanted with an early version of CI
1968
What was going on in the 1970s?
Work on stimulation of the human visual cortex
NIH supported auditory stimulation
When did the FDA approve cochlear implants?
1984
What are the three parts to a CI?
Internal Package
Speech Processor
Electrode Array
Where is the internal package found?
Under the skin, behind the ear
Where is the speech processor found? Where was it located in the past?
Behind the ear (like a BTE hearing aid) and connecting the the internal package via a magnet
Used to be a box unit
Where is the electrode array found?
In the cochlea
Does the electrode array go all the way to the cochlea’s apex? Why or why not?
No. It is too narrow and the electrodes don’t fit
What does a CI provide?
Functional hearing to individuals with severe-profound hearing loss
What are the three companies that make CIs?
Cochlear Corporation
MedEI Corporation
Advanced Biotics Corporation
Advance Biotics was recently sold to ______. They are currently working on ______.
Phonak
Combining HA & CI tech
What are the four parts of the CI internal receiver?
Magnet
Receiver coil
Electrodes
Electronic Platform (Computer Chip)
How are CIs implanted?
The internal device is place surgically underneath the skin behind the ear.
The electrical array is placed in the cochlea. This delivers electrical stimulation to the auditory nerve.
What does the CI receiver do?
Decodes the signal from the speech processor
What does the CI electrical array do?
Converts the code into electrical signal
This stimulates the nerve fibers and auditory nerve
Are all CIs programmed with the same software?
No. Each company used different software
Can you mix and match parts of CI designed by different companies?
No. You can’t even mix part by the same brand as they are connected with a recognition/locking code.
The CI electrode array is put in the cochlea’s ______.
Scala tympani
The CI electrode array is _____.
Tonotopic
What provides the frequency resolution for the CI?
The auditory nerve and the brain
How does a CI work?
5
Microphone captures sound
Signal is converted into digital code by the speech processor
This code is transmitted by an FM signal across the skin to the internal device
The computer chip decodes this signal and sends an electrical signal via the electrical array
The electrical array stimulates the nerve fibers and the auditory nerve delivers this information to the brain.
What, in regards to the cochlea, do we assume with CIs?
The the root of the missing inner hair cells will pick up the signal
What are the four external components in CIs?
Microphone
Speech Processor
Transmitter Coil
Magnet
What powers the CI? Where is the power source located?
Batteries
Speech processor
What is the name of the Advanced Biotics Speech Processor?
Harmony
What is the name of the Cochlear Corp’s Speech Processor
Nucleus 5
What is the name of MedEL’s speech processor?
Opus 2
The common task of ALL cochlear implant systems is the convert the acoustic input signal into an ______ that yields _____ and allows for ______.
Electrical signal
Speech clarity
Speech recognition
What is the magic number (age) for cochlear implantation?
7 years
How is a CI different from a hearing aid?
3
Bypasses the outer and middle ear - needs no acoustic amplification
Bypasses damaged or missing hair cells
Stimulates auditory nerve directly!
What is a CI MAP? How is it designed?
The CI programming that is written on the chip in the speech processor
Designed for the individuals particular ability and need
When is the CI MAP usually done?
After surgery and healing time. Usually about 4 weeks
What does the CI MAP do?
Tells the internal device how to deliver sound to the electrodes
Are CI thresholds calculated in dB?
No. They are calculated in electrical current
What is the first choice in designing a CI MAP?
Which speech coding strategy to implement
What are the three parameters of sound processing used in CIs?
Frequency (the site of stimulation)
Amplitude (the amount of stimulus)
Time (Rate & pattern of stimulation)
What does NRI stand for?
Neural Response Imaging/Telemetry
What is NRI?
Electrically evoked responses on the electrodes
Used to confirm settings in babies and in adults who are poor reporters
Which ear should be implanted?
This is a controversial issue
Why do some people think it’s best to implant the better ear?
Better neurons should mean better performance
Why do some people think it’s better to implant the poorer ear?
To save the better ear for new tech (improvements)
To maintain hearing aid use in the better ear
Who gets to make the final decision on what ear to implant (assuming there is not physical reason that one ear is not a candidate)?
The patient
What are the three similarities between the three CI companies?
Electrical stimulation
Internal & External components
Outcomes
What are the four differences between the three CI companies?
Length of electrode array
Speech coding strategies
Number of channels
Stimulation rates
Who could receive CIs in 1985?
4
Adults 18+
Postlinguistic HL
Profound SNHL
Open set speech understanding = 0%
Who could receive CIs in 1990?
4
Adults and children over 2
Postlinguistic adults
Pre/Postlinguistic children
Profound SNHL
Open set speech scores = 0%
What were the qualifications for adults to receive CIs in 1998?
(3)
Pre/Postlinguistic HL
Severe-Profound SNHL
Open set speech scores = 40% or less
What were the qualifications for children to receive CIs in 1998?
(3)
18 months or older
Pre/Postlinguistic
Lack of auditory progress (less than 20% on pediatric word tests)
What are the present qualifications for adults to receive CIs?
(3)
Pre/Postlinguistic HL
Bilateral Moderate to Profound SNHL
Open speech set scores = 60% or less in contralateral ear, 50% or less in implanted ear
What are the present qualifications for children to receive CIs?
(7)
12 months or older (exception menigitis)
Pre/Postlinguistic HL
Bilateral Moderate to Profound SNHL is children older than 2
Bilateral Severe to Profound SNHL is children less than 2
Lack of auditory progress and speech development with amplification
No medical or radiologic contraindications
Appropriate family expectations
What open set sentence test score does medicare require?
40% or less
What are some expectations (not promises) for postlingual adults who receive CIs?
(4)
Good open set speech understanding
Good understanding in noise
Ability to use the phone
Ability to enjoy music
What are indications for CI referral for pediatrics?
3
ASAP - Don’t wait!
Infants & children with severe to profound HL
Lack of progress with amplification
What can affect CI success in congenitally deaf pediatric patients?
(4)
Pre-implant thresholds (both aided and unaided)
Age when amplification was initiated (length of HA use)
Amount of aural habilitation
Age at implantations
What are expectations with pediatric CI patients?
Normal speech and language development
No need for special ed placement
