"THE HEART OF THE MATTER"
a special program of the National Emergency Medicine Association (NEMA)
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Week: 599.7 (reprise of 580.6)
Guest: Peter Arkis, audiology, Warren Otologic Group, Warren, Ohio
Topic: Helping the deaf hear again
Host/Producer: Steve Girard
NEMA: For many deaf people, improved procedures offer the chance to shed the isolation of silence, and hear the richness of life. The cochlear implant is a marvel, and our guest today is Peter Arkis, the audiology and speech specialist at the Warren Otologic Group in Warren, Ohio. Lets talk about the process of hearing first....
ARKIS: A sound wave is a pressure wave. So, the sound enters, is collected by the outer ear and is funneled down the ear canal to the eardrum. That pressure wave causes the eardrum to vibrate, and pass the vibration to an area called the cochlea, which is in the inner ear. The cochlea is a fluid filled organ, and the nerve ending, the hearing nerve ending is inside the cochlea. As the sound wave comes in, it sets up a wave in the fluid, stimulates the nerve endings..so the inner ear is a transducer...it changes energy from mechanical vibration into an electrical impulse, thats carried by the hearing nerve up the the auditory center in the brain....and then its converted back into sound.
NEMA: During a cochlear implant, where does the surgery intervene in that system...and where does it rejoin?
ARKIS: In a healthy, normal ear, theres approximately 38 thousand nerve endings called hair cells in the inner ear...in the cochlea. Typically those hair cells convert mechanical energy into electrical energy. In cases of deafness, the hair cells have been destroyed, and as a result, the vibration gets to the cochlea, but theres no transducer left. So the vibration gets to the inner ear, but thats the end. So what we do with the cochlear implant is we implant tiny wires or electrodes in the inner ear to replace the hair cells, or the nerve endings. So the implant has a microphone somebody wears, similar to a hearing aid microphone, picks up the sound....but the sound is converted into an electrical energy, and those electrical impulses are placed on the electrodes in the cochlea...so were replacing those little nerve endings.
NEMA: How has the procedure changed since it was first performed?
ARKIS: Research was being done on cochlear implants in the 60s and 70s. A lot of the initial work was done by a physician in Los Angeles named William House...the original implant that was used. It was called a single channel device, because it had one, single electrode that was implanted in the inner ear. That device provided sound awareness to patients...they could hear the sound of the voice, and get the rhythm patterns of speech, but were unable to understand speech without lip reading. Around the mid 80s, multi-channel cochlear implants became available. That had 22 electrodes that were placed inside the cochlea. And with that device, people were not only able to hear sounds, but they were able to understand speech.
Theres been a great deal of improvement in the technology, and mostly in the coding strategy...what the coding strategy is, is this: the implant, in addition to the implanted portion, has an external hardware that the patient wears, which includes a battery pack, a microphone and a miniaturized computer. The computer chip analyzes the speech signal and puts it into a special code. And over the years, the improvements have been that weve become much better at coding the speech signal, and as a result, patients performance has continued to improve pretty dramatically over the last dozen years or so.
So that today, the majority of patients are able to understand speech and almost 70% of the patients who had hearing and lost it are even able to carry on a normal telephone conversation.
NEMA: So, a patient can now hear without carrying around any obtrusive gear?
ARKIS: All the current devices have an internal component which are the electrodes that are placed in the cochlea...and then a whats an area, a package called the receiver/stimulator, that has electronics in it that is placed near the mastoid bone, which is the bone behind the ear. But everything now is underneath the skin, so that patients can go back to their normal routine after about 4 weeks after surgery to let everything heal up, but they can swim or do whatever they want to because everything is under the skin. Now, in order to activate the implant that is in the mastoid and in the cochlea, they wear an external component that has a microphone that picks up the sound, a speech processor that analyzes it, and a transmitting coil thats coupled magnetically...so the implant underneath the skin has a magnet on it. The head piece has a magnet, so they stick to each other in a line. And the transmitter uses radio frequencies to transmit information across the skin to the implant. So, theres no wires or anything that come through the skin.
NEMA: Are the prime candidates for this people who have had hearing and then lost it?
ARKIS: ...typically what we look for, especially in adults, are people who have had hearing and lost it. Termed post-linguistically deafened adults. The reason for that is that the auditory pathways have developed and they have whats called an auditory memory...they remember sound and remember, not just environmental sounds, but what speech sounds like. So, typically they are the best candidates, but were finding that if children are identified very early in life, and implanted very early...and by that I mean maybe by age 2... they grow up hearing, and can develop very good speech and language. So, in young children, even if theyre born deaf, if theyre identified early and implanted early, theyre still good candidates.
NEMA: What is the course of the rehab after someone has a cochleal implant?
ARKIS: They have the implant, and then we wait about four weeks for healing. And then we program the speech processor, which youll remember is a miniaturized computer that they wear. At that point, what we used to do with adults was bring them back every week or so...but what we found over the years is thats not as critical in adults.
For example, one of our fairly early patients, came in after surgery and I was able to program him. And we didnt see or hear from him for about a month, actually. And one day, the receptionist buzzed my office and told me that Ron was here...and he was very apologetic because he had missed his rehabilitation appointments. And he told me that he was at home, He heard the phone ring and decided since he was the only one home, hed try and pick it up. So, it turned out to be his aunt...who was very upset because of a death in the family. He spent a few minutes on the phone with her...made a couple of other phone calls to other relatives to let them know...called the funeral home to make some arrangements, and then was busy for the next few weeks with that family tragedy. So, he came in said, "Im really sorry I didnt come back for you to teach me how to hear again". So, its pretty obvious at that point that there wasnt really much that we could teach him to do if he was already using the phone after a week....
Now, with children, its a different story. They still require a lot of speech and language therapy...and more frequent programming.
NEMA: So now that weve refined the technology to the point that patients can understand speech, it seems one of the points of our talk today ought to be about getting out the word that help is available, even to the smallest child...and to have those babies checked out....
ARKIS: Thats really critical, theyre finding more and more that the early identification is critical, and not just the identification, but the starting of fitting of hearing aids and getting them started in therapy. Another thing that would be important to know is with current technology, we are able to test hearing in children as young as a day old. We see them, and theyre already 2 years old, and theyve missed a lot of critical time in between. So, thats really important is the early identification.
NEMA: About the quality what an implant patient hears...is it close in tone and texture to regular hearing? Do adults sound like adults? Does music sound like music?
ARKIS: As compared to a normal, hearing ear...it does have a reduced frequency range...however, its designed specifically for the area thats called the speech frequencies...the frequency range where voices occur and where speech occurs. And it does a very good job in that range. So Ive had people tell me I sound anything from Mickey Mouse to Darth Vader. But if you ask them the same question after several months, six months to a year, "now whats it sound like"? They say, "...what do you mean, it sounds like your voice". So that their auditory system, their brain, adapts to this sound and it becomes more normal sounding to them.
NEMA: As we continue to improve our technology, the chance for deaf people to hear the sound of important voices...their friends, relatives...their children, continues to get better. Id love for them, for instance, to be able to hear this medium, this station, me...with more stories on triumphs in other areas of medicine and treatment. Thanks to Peter Arkis of Warren Otologic Group in Warren, Ohio.
SPOT: 15 years in the prevention of heart disease, stroke and trauma - The National Emergency Medicine Association. This show is just part of what NEMA does. We send out millions of pieces of prevention information to people around the country, give grants to organizations in research, public information and emergency services, and have been instrumental in the creation and expansion of the Chest Pain Emergency Room movement. To play a role, call 800-332-6362.
NEMA: Thanks for joining us for todays program. If you have any comments or suggestions, contact this station. Or visit our home page at: www.nemahealth.org/...for a look at transcripts of this or past programs, or to find out more about the National Emergency Medicine Association. Im Steve Girard at The Heart of the Matter.