Wednesday, October 21, 2009

Cochlear implants give performance similar to HAs with 80db HL

This study shows CI matches HA with 80db HL

Comprehensive study that demonstrates medium-gain HAs with only 40db gain was able to match the average CI result except in HINT+5 where HAs were significantly ahead!
The average HA was 78db PTA unaided, 38db aided. For CI it was 110db HL aided down to 36db.

My comments: With a 110db HL, even high-gain HAs with 70db gain would aid you down to only 40db. Speech scores with such a profound loss would be far below the scores of CI and those with severe losses because there's extensive cochlear dead regions associated with a 110db loss. Also the surviving hair cells would be of very low quality and contribute little to acoustic information.

CI matches HA with 90db HL

Ive been doing my research on comparing CI vs. HA and I found this! I will keep looking for more articles that compare the two. But from what ive researched, CI today usually gives better hearing than what HAs can give for a profound loss. But CI appears to match the performance of HAs for a severe loss.

I also learned that those with severe losses generally score at least 70% speech on a difficult monosyllable test. I will do more research on speech scores for different degrees of hearing loss. But that article does show that those with profound losses generally scored below 50%. It's that group who with CI could hear comparable to those with severe losses and HAs. Speech would improve from perhaps 40% to perhaps 80% which is significent.

HAs come out way ahead of CIs in most tests

Results: The aided pure-tone hearing thresholds of the hearing aid users were better at low frequencies. In contrast, the cochlear implant group’s thresholds were better at high frequencies. with a statistically significant difference at 250 and 6000 Hz.. The hearing aid users had similar scores to the normal hearing group in vowel identification and pattern perception. In addition, the hearing aid group performed better than did the cochlear implant group in vowel identification, pattern perception, and daily sentences tasks (P = .001, P = .02, P = .0001, respectively). No significant differences were found between the hearing aid and cochlear implant groups in multi-syllabic, phonetically balanced words, and consonant identification tasks. Although similar performances were obtained for three groups in music perception tasks, there was a positive and significant correlation was found between pattern perception and rhythmic perception ability of the cochlear implant group, whereas the hearing aid group, who had better performance in multisyllabic word discrimination, also performed better in tonal and rhythmic tasks.
My comments: Hearing aids are great, no need to say any more!

FIGURE 3. Advances in technology and signal processing in cochlear implants have resulted in improved performance outcomes over time. Shown are group mean percent correct scores for CUNY and HINT sentences in quiet, and for CNC monosyllabic words. Source: Internal data from Cochlear Americas clinical trials.
My comments: CI performance improvement has peaked and leveled off since the early 2000s. Future technologies won't even be CI based as CI has physical limitations due to physics and principle.

Results of Pediatric Cochlear Implantation Compared with Results Obtained with Hearing Aids

Profoundly deaf children with 110db HL and 22% speech improved to 72% speech after CI and they hear with CI comparable to those with a severe hearing loss(70-85db) younger children did better with CI, the performance of children implanted between age 2 and 4 was equivalent to the mean performance of children with hearing loss of 70-85 dB wearing hearing aids.

Image got cut off, to view in full, click here

My comments: The HI group had only 55db PTA HL while the NH group had 5db PTA HL. Properly amplified, a moderate HL(60db max) which involves only the OHC and not IHC can give you near normal hearing except in the most challenging situations. Even with a channel simulator, the NH and HI did far better than CI. CIs do a great job in quiet but not so well in noise. It should be known that CIs aren't a cure and they won't give you anywhere near normal hearing, but they can be great for the profoundly deaf.

I found a recent CI study that shows the average performance for CI speech scores. Different studies show slightly different scores. The concensus is that CI can match HAs for someone with a severe hearing loss. CI is usually better than HAs for those who are profoundly deaf so it's no surprise many become CI candidates.


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  2. they are bone marrow cells. the research 4 to 5 years ago

  3. have any information on whether it is applied in humans? Or apply in humans in the near future?
    greetings and thanks for your interest

  4. hi
    China may have allowed treatment. You need to exercise caution and note this is still very new. In my country, it is still banned.

  5. Gene therapy was almost thrown out when a death occurred and a few cancer cases surfaced a few years ago.

    Now gene therapy has success again. The below article may suggest similar treatment pattern for hearing loss, balance disorder and the hearing-loss-induced T , by similarly using the healing atoh1 gene.

    See (external link, opens new browser window)

  6. Functional auditory hair cells produced in the
    mammalian cochlea by in utero gene transfer

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  8. Once again you are refering to studies but not giving a reference so that we can review the evidence ourselves.

    It's dangerous to masquerade your opinions and extrapolations as scientific fact.

    I can tell you that my experience of a CI versus a HA is that the CI wins outright. I can hear in quiet, I can hear in noise. I don't hear perfectly with the CI - after all I have only had it for 3 months. If it never gets any better then I am happy as I have heard better than I have done for years.

    Are you afraid of getting a CI? why are you so anti them?

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  10. hi mog

    As you already have a CI, which is irreversible, you should never ask for the benefits of other treatments. You are only asking for no end of misery and anguish if you are proven wrong. Stop reading posts like this and enjoy your life

  11. Mog, there's not much evidence on humans getting stem cells at this time. However in animal clinical trials, it has been shown to give a 20-30db improvement. A stem cell lab in China is saying humans are getting the same amount of improvement that was seen in animals.

    Im going to create a new post soon and provide all my facts with links to stem cell research. I should be clear that my comments are my opinions and the facts are in the sources.

    Ive been researching on CI vs. HA and so far, the evidence points out that CI matches 80db HL with HA. You have way more than 80db HL at all frequencies above 500Hz but way less than 80db HL at 500Hz and below. Looking at results for low pass filter at 500Hz vs. CI, the CI still does come out ahead vs. good hearing that is limited to only 500Hz. So your subjective and objective results of CI being better agrees with what ive researched.

    I am not against CI and respect your choice for CI. It's your ears and risk. I am not comfortable with the surgery and risks that follow with CI, losing my residual hearing and missing out on getting stem cells. I read a post in your thread that you think itll take 20 years for stem cells to be "approved" and no longer experimental and for insurance to maybe pay for it(no guarantee)

    I surely am not waiting 20 years for FDA/government approval of stem cells in America or Canada. Also no one knows if insurance will even pay for stem cells to treat deafness. Insurance won't even pay for HAs! With that in mind, I am saving up $30,000 and am traveling overseas or to Mexico where stem cell technology in those countries are far ahead of America and at a far lower cost.

    I might be able to get one CI free, but itll still cost $50,000 to get a 2nd CI as id like to hear in both ears. Stem cells for $30,000 can improve both of my ears and from what I read, itll give better hearing than CI with far less risks. My family and friends strongly support stem cells over CI.

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  13. Thanks for the news, Miguel!

    Studies are also underway to learn about stem cell treatments to address blindness by introducing retinal and corneal stem cells and deafness by re-growing the cochlear hair cells which allow us to process sound.

    From what I read, umbilical cord blood stem cells can treat deafness. Ive also read that several other types of stem cells are being researched on treating deafness. This is great because it presents more options and better chance of success!

    I hope the news eventually comes out regarding those two patients getting stem cell treatment in the next two months. Before, after audiograms, speech scores and all other information will encourage me and others to seek treatment next in line after those pioneers. The wait might not be long at all depending how much progress is made and how much information is disclosed of the pioneer's stem cell results. A trip to Mexico across the border from San Diego, CA would be far easier, faster, cheaper than a trip overseas.

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  15. RNL BIO Rescues a College Student from Autoimmune Hearing Loss
    - RNL BIO's success of stem cell treatment


  16. First Successful Case Example of a Hearing Loss Cure in a Human Patient?

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  18. Hey- I posted a reply to your comment on my blog. Read it :)

    I respectfully disagree. I was diagnosed with a moderately-severe hearing loss when I was three. I hear sounds with my CI that I never heard with my hearing aids even back then. If I could have gotten stem cells when my hearing dropped, it would have just brought my hearing back to where it was when I was little. I hear better with CIs then I did with a 50-70dB HL, so, to me, stem cells are just a little bit too much hype.

    -and, even if my CI hadn't worked, I retained residual hearing in both ears. (This comment sort of goes for your last 2 posts, but it seemed to fit more with this one...)

  19. Do you have any older audiograms to scan and post? I have some audiograms on my blog. The articles show numbers in db and speech. You have the 2nd best CI result ive ever seen. The *average* CI is far, far, far below what you hear with your CI.

    I have no idea what HAs you wore or how well they were programmed and how much amplification you got. My HAs are capable of a 70db gain so if stem cells gets my hearing improved to 70db HL, I potentally could hear at 0db! This will at least match the sounds you hear with your CI. As for speech, it would depend on my brain's capabilities but I expect to score at least 80% anyway.

    Chloe's stem cells got her hearing to where she hears without HAs so it's possible stem cells could have done the same to you or anyone. It remains to be seen if Chloe's results are the best possible and that *average* results are far less. I have realistic expectations and just hope to get to 80db, even 70db would be nice and with my HAs, hear at 10db or better. This far outperforms average CI at 30db.

    How much residual hearing did you retain? My audiologist told me if I get CI, I can never go back to HA if CI doesn't work. Ive also read around that keeping residual hearing is very important regarding a successful outcome with stem cells and that the more residual hearing you have, the better youll hear after stem cells. Is your residual hearing expected to last?

  20. Dear deaf dude,

    Thanks for the links to the useful articles. I have found these very useful. I hope you found my comments regarding stem cells in your more recent posts helpful also, in particular the one pasted earlier today. Keep searching for answers ;)

  21. Is there a place I can go to figure out all of your abbreviations? I'm interested in learning more about what you have to say, but I have no idea what HA, HL, and CI mean.