Delta's Sky magazine

My dad flew on Delta for the business trip. He found an article interesting in the Sky's magazine as of December 2005. He brought the magazine for me to read!

Click for the article: The Human Cyborg

Thanks Dad.

Auditory Performance of Cochlear Implantees

Here's interesting information from National Institutes of Health.

What Factors Affect the Auditory Performance of Cochlear Implant Recipients?

Subject Factors

Auditory performance, defined as the ability to detect, discriminate, recognize, or identify acoustic signals, including speech, is highly variable among individuals using cochlear implants. Since the 1988 CDC on Cochlear Implants, however, some factors associated with outcome variability are now better understood.

Etiology

Because of a larger subject sample, the effects of etiology can now be distinguished from other factors such as the duration of deafness and the age of onset. For example, deafness due to meningitis does not necessarily limit the benefit of cochlear implantation in the absence of central nervous system complications, cochlear ossification, or cochlear occlusion. Children with congenital deafness and children with prelingually acquired meningitic deafness, for example, achieve similar auditory performance if the cochlear implant is received before age 6. In general, etiology does not appear to affect auditory performance in either children or adults.

Age of Onset of Deafness

The age of onset continues to have important implications for success with cochlear implantation, depending on whether the hearing impairment occurred before (prelingual), during (perilingual), or after (postlingual) learning speech and language. At the last CDC, data on cochlear implantation suggested that children or adults with postlingual onset of deafness had better auditory performance than children or adults with prelingual or perilingual onset. Current data about auditory performance in children over longer times support this finding. However, the difference between children with postlingual and those with prelingual-perilingual onset of deafness appears to lessen with time. Large individual differences remain within each group, however.

Age at Implantation

Previous data suggested that prelingually or perilingually deafened persons who were implanted in adolescence or adulthood did not achieve the same level of auditory performance as those implanted during childhood, although individual differences were recognized. Current data continue to support the importance of early detection of hearing loss and implantation for maximal auditory performance. However, it is still unclear whether implantation at age 2, for example, ultimately results in better auditory performance than implantation at age 3.

Duration of Deafness

As deafness endures, even in postlingually deafened individuals, some auditory and linguistic skills may decline and some behavioral traits that work against successful adaptation to a sensory device may develop. Individuals with shorter durations of auditory deprivation tend to achieve better auditory performance from any type of sensory aid, including a cochlear implant, than do individuals with longer durations of auditory deprivation.

Residual Hearing

Initially, cochlear implant use was restricted to persons with profound hearing loss (pure-tone threshold average (PTA) of greater than 100 dB HL and no open-set speech recognition ability with best-fit hearing aids). The average auditory performance of these cochlear-implant users has been better than the average auditory performance of hearing-aid users with some residual hearing, that is, severe hearing loss (PTA > 90 dB HL) and some (<30 percent) open-set speech recognition ability with best-fit hearing aids. Recent data show that auditory performance in people with residual hearing improves after cochlear implantation relative to preoperative auditory performance, although the degree of improvement could not be predicted from preoperative hearing sensitivity. Research is now addressing the critical distinction between the importance of residual hearing sensitivity compared with overall residual auditory capacities and functional communicative status.

Electrophysiological Factors

Some surviving spiral ganglion cells are necessary for auditory performance with a cochlear implant. Degenerative changes occur in both ganglion cells and central auditory neurons following sensorineural deafening. Although a relationship between the number of surviving ganglion cells and psychophysical performance has been demonstrated in animals, a direct relationship between ganglion cell survival and level of auditory performance in humans has not been shown. Animal studies also suggest that electrical stimulation increases ganglion cell survival and also modifies the functional organization of the central auditory system. The implications of these new findings for humans remain to be determined.

Device Factors

The task of representing speech stimuli as electrical stimuli is central to the design of cochlear implants. Designs vary according to (1) the placement, number, and relationship among the electrodes; (2) the way in which stimulus information is conveyed from an external processor to the electrodes; and (3) how the electrical stimuli are derived from the speech input (and other signals). Changes in cochlear implant design/processing strategies and their effects on auditory performance are discussed in the section on technical and safety considerations.

Source: What Factors Affect the Auditory Performance of Cochlear Implant Recipients?

Second Activation

I was back to JHLC for the second time. I was re-mapped to get 3 more channels. I was able to get sensations from channels 21, 20, and 19. Yesterday, I didn't get sensations like that, I guessed that it takes time to have my brain and nerves to adjust and it helped to spread to more channels.

Same thing, channel 22 gave me sensations behind my right ear. Channel 21 gave me muscle twitching in my upper lip, so audiologist reduced lower level to prevent muscle twitching. Then channel 20, I get like little pain in my head and shoulder. Audiologist also reduced to comfortable level. Same goes for channel 19, it gives me some feeling behind my head. After it was remapped, and she left 4 channels on and 18 other channels off. She gave me 4 different programs in my BTE processor (Behind the ear). All four programs contain same mapping, but use different strategies such as ACE, CIS, etc. She asked me to switch to different programs during one week period. When I come back for next week's activation, I will need to tell her which 4 programs are best for me and she will focus on this strategy and probably also the second best strategy, and to increase more channels as well. I am seem to get more sensations than I did on the first activation.

After everything were finished, I asked her about baby cry, and I wasn't able to hear my daughter crying... She said that cochlear implant is not similar to hearing aids which simply amplifies to louder sounds. Cochlear implant only sends electronic signals to the nerves, and the nerves still doesn't recognize the sounds, either loud or soft sounds. It takes time for the brain to adapt and re-wiring the nerves from sensation feelings to hearing sounds. So my daughter's crying/screams aren't yet recognized in my brain, and I am not still hearing it yet.

So far I am progressing and I keep my faith in God to help me with the whole progress.

First Activation

On December 19th, my wife, my daughter and my mom couldn't attend to my first hookup day, because my wife and my daughter were sick with the stomach flu. My daughter had been vomitting since Friday night, and it is almost full three days that she had been vomitting. It seemed very serious for my daughter, so my mom called the advice nurse for me. Also, my wife got sick in the same morning as my first activation, she wasn't feeling very well. So there I went with my dad to the appointment at Johns Hopkins Listening Center.

My audiologist was running the electrode cycles throughout all of the channels... It made me felt like little weakened on my whole body and little dizziness experienced. But then she ran channel 22, I heard nothing, nothing, nothing... then little pain simulated behind my ear, I told her I get the pain so she marked it there. Then she went on to the channel 21, nothing, channel 20, nothing, channel 19, nothing. So she set only channel 22 on, and the rest of the channels were set off. My map was using ACE strategy and I am only experiencing sensations like little pain spasms against my right ear. None of these sensations do make sense... So I let my CI running through my head today all afternoon and night.

After the appointment was over. My dad and I were on the way to my home, then my mom called that she wanted us to meet at her home instead to admit my daughter to the urgent care. My wife went along with my mom and we met at my parent's home. My dad had to stay at home because of his business trip to Tennessee and Michigan. He had to get up about 3am for the airport shuttle. So I drove with my mom, wife and daughter to the urgent care. After we were there, we asked if my wife could go in for appointment as well. They accepted and had my daughter and wife going through blood tests and the nurse put IV into my daughter's arm and she screamed out loud. My wife was put on IV also. When my daughter screamed, my mom asked if I heard that... I told her no, I don't.

Chris Roberts, CEO of Cochlear - 'We have a unique opportunity'

Roberts recently spoke with BusinessWeek's Bruce Einhorn about what's in store for people who are losing their hearing. Edited excerpts follow.

What sort of advances can we expect in hearing technology?

It's still early days in terms of where the technology is going. We are going to see significant advances in the next three to five to 10 years. There's a lot happening.

So what is Cochlear trying to do?

There aren't many companies working in this space. We have understanding of hearing, of implant technology, we work with opinion leaders. [For many people with hearing loss,] you need things other than cochlear implants, you need cochlear implants plus.

What can you offer such people?

One is an electro-acoustic type of device. Cochlear implants work very well at high frequencies, but if you have a little bit of residual hearing, it's often at the lower frequencies that you have it. So it's been that people wait until they have lost hearing enough so that if you put an electrode in the cochlear, there's no downside.

What you would like to be able to do is to preserve what little bit of hearing they have. What we want to do is put an electrode in for the higher pitches -- typically for speech -- and acoustic stimulation for the lower frequencies. We need to work with the surgeons to develop electrodes that are atraumatic, so you can put the electrodes in the cochlea and preserve those delicate structures [of the hair cells in the inner ear].

How big is the potential market for these hybrid devices?
There are probably 50 to 60 times more patients who would be suitable for that device than for a cochlear implant.

Is this something that people will be able to get soon?
There's a trial going on at the University of Iowa [with] interesting results. There's real stuff going on. [The timing] is a couple of years off -- it's not months, but it's not decades. There aren't many people in the world working on this. I think we have a unique opportunity to really contribute to this space.

...

Today, very few people with cochlear implants have them in both ears, but you've said that you see a trend toward having bilateral implants rather than unilateral ones. Why?

There are probably 50,000 to 100,000 people who go single-sided deaf a year. Thirty years ago, if you got a hearing aid, you got one. Now you get two. We listen with two ears for good reason. I don't know when it will happen, but it will happen that kids will get two. It might be five or 10 years before it's routine.

Cochlear implants are controversial among some people in the deaf community who are opposed to parents getting the devices for their young children. What do you say to them?

I think that their opposition is becoming less and less. And that's through the results. These children may be in deaf schools before being mainstreamed, and the teachers see these kids get transformed. You can't look at these results and say they're not real -- it's very hard to argue against technology. If you look at these kids [with hearing because of implants], you can't say you want to take that away from them.

Source: READ FULL ARTICLE AT BUSINESSWEEK

Many misconceptions

I have gotten many misconceptions from someone I know about how cochlear implant works.

I had a deaf friend who feared about drilling and creating hole, he said do I have hole in my head? I told him, "Here it is look at my head, do I have any hole?" He said, "Huh, no. Can you hear now?" I told him, "No, I don't have external components, once I have external components at the first hookup day, then I may be able to hear with it." He said, "How?" I explained about magnetic connection over the skin, just like kids love playing by putting a paper between two magnets. So he said like, "Oh! Got it."

Even he is much involved with the Deaf culture... He was simply ignorant on how CI works. Even he thinks that I couldn't go swimming!

Here's the interactive flash video on how the CI works... Very good one.

WATCH THE INTERACTIVE FLASH VIDEO

Miss America in 1995, Cochlearized in 2002

From Cochlear Corporation:

In 1995, Heather Whitestone, deaf since infancy, was crowned Miss America. She was the first disabled woman to receive this honor. Now, Heather is embarking on a new path into the hearing world. On August 7, 2002 Heather received the Nucleus® 24 Contour™ cochlear implant. Her surgery was performed at Johns Hopkins by John K. Niparko, M.D., one of the nation's leading cochlear implant surgeons. Heather's device will be activated during mid-September.

Learn more about her, visit:
Cochlear Corporation on Heather Whitestone
Heather Whitestone's website

Complex Surgical Conditions: Ossification and Dysplasia

I have severe ossifications in my both ears which was caused by meningitis. Left ear seems to be completely solid and my right ear is partly ossified. So that's why my surgeon chose my right ear to implant. It was about 80% of electrodes implanted into my right cochlea.

So here's interesting info from University of Miami School of Medience:

Cochlear implant surgery is usually a routine procedure taking one to two hours under general anesthesia as an outpatient. However, when the fluid spaces of the cochlea are partially or totally filled with abnormal bone, or when the cochlea or other structures are not formed properly, cochlear implantation is more complex.

The cochlea may fill with bone in response to inner ear infection, meningitis, auto-immune inner ear disease, ototoxicity, and other conditions. It is called ‘labyrinthitis ossificans’ and can be diagnosed by CT or MRI. Surgical techniques have evolved that allow cochlear implantation even in such cases. When the cochlea is only partly obstructed, surgery is usually straightforward and results are very good. When the cochlea is completely filled with bone, surgery is still possible but is more complex and results are variable.

The same is true of inner ear malformation, usually called ‘dysplasia’. Milder forms of dysplasia such as enlarged vestibular aqueduct (EVA) and Mondini syndrome require surgery that is straightforward and have excellent results. However, severe dysplasia, such as common cavity deformity, requires more complex surgery and results are variable.

Source: UMSM's Cochlear Implant Center

Here's my ct-scan image of my right and left ears. You will see solid whites which is an ossification. In the right cochlea, you will see little grayish hole in there. It means very little space for the electrodes to be inserted. My surgeon said that ct-scans is not perfect image of what's really there... it may be more or less space to insert. (image to be posted soon)