Residual hearing?

[MosDeaf]

One of the main reasons I am looking at Med-El is that I am told there is a chance to retain my residual hearing. Has any one had this happen? I would like to keep as much of my natural hearing as I have left.

[Jodi]

Hi, my husband had his implant 2 years ago.  He has retained some residual hearing but it is so minor I am not sure if it has any real advantage.  Maybe, you will have more luck.  Its worth trying.

Diane

[mzabalau]

The residual hearing depends mainly on the ability of the doctor that is actually manipulating the electrods inside the cochlea. This was a key question before implantation of the second implant to my daughter. In Spain, one of the most experienced doctor says he could keep 80% of the residual hearing. A friend that went to New Yorks main specialist would not consider more than 50% is possible. Nevertheless what is kept after surgery, they all agree that the levels decrease in the next two years, as the ciliar cells are not being any more adequatly stimulated. You can read more about this in http://www.ncbi.nlm.nih.gov/pubmed/20818293 and http://www.med.unc.edu/earandhearing/research/pdfs/Residual_Hearing.pdf

[maleka]

I am seriously considering going bilateral after having an implant in my rt ear for the past ten years. Ive lost all residual hearing in my rt ear however the surgeon seems very confident that he will be able to keep at least 75% of the hearing i have left in my left ear after the implant. I still can use the phone in my left ear and cannot use in my implanted ear so i guess my big question is how much of the residual hearing remains as the years go on or does it gradually diminish as it did in my rt ear. This can be a deal breaker even though there are a lot of beneficial reasons to go bilateral. any thoughts or comments are greatly appreciated

[jadepedro]

I can't speak by myself, but I found a blog of a girl that went bilateral and seems to be happy with her decission. I think she is wearing medel: http://www.sarasera.com/ Maybe you can contact her.

 

Best regards and wishes

[Sinker]

I just got the Flex 28 electrode in Dec. '12 so it is long & deep in the cochlea.  I lost a lot of residual hearing where I had it @ 65 dB, basically worthless now at 95 dB.  Surgeon said going into surgery, don't depend on retaining anything usable.  I was only testing 13% word recognition with a hearing aid anyway, so no great loss except some sounds that might alert me to the sky falling or something.  Also, I have progressive loss so I was going to lose it soon anyway.  I think if one had a shorter electrode where there was actually something worth retaining, that is the best scenario, flex or not.

[hearingmiracle]

it seems like a shorter electrode is better than longer electrode due to ability to retain the residual hearing

[jcech344]

I would like to revive this topic.  I had my surgery roughly 4 months ago.  I had a Flex 28 inserted using an IotaSoft robotic insertion. After 3 months I can say that the only functional residual hearing I have is in the low frequency range.  Nothing in frequencies over about 150-200 Hz.

I have read that the primary cause of loss of residual hearing is trauma resulting from translocation of the electrode array into the scala vestibuli.  While this has only a small effect on the performance of the CI absent major damage to the spinal ganglions, it does destroy residual hearing.  The primary argument from Med-El for lateral array design (vs contoured arrays) and the wavy nature of the wires within the electrode is to minimize this.  Articles using cadavers show a >90% placement in the scala Tympani. The CT scan done after insertion showed (I am told) that I had complete placement in the ST.  If so then why the loss of residual hearing?

Little data has been available on this nor have I seen any mechanism for feedback to ME on outcomes to use to help develop improvements.

While I am disappointed with this outcome I want to be clear that the quality of my hearing conversations has improved dramatically as a result of the implant.  I was prepared for this potential outcome (loss of residual hearing) and have no regrets having made the decision to do this.

Interested in the experience of others.

[Mary Beth]

Definitely a topic with varied opinions at this point.  Some studies showed that surgeon experience had a minimal impact on preserved hearing.  However many professionals specifically mention that certain surgeons have great track records of preserving residual hearing.

I have been very intrigued by CI users who initially have preserved hearing and use an EAS fitting and then several years later lose their preserved hearing and need to adjust to a full CI fitting.  That transition seems to be very difficult for many people.

[Kilgary]

My surgeon warned me that even if she placed the array as delicately as possible by human hands, there will be ossification around the array in the months following implantation leading to damage of the remaining hair cells. Sure enough, I lost virtually all my acoustic hearing in my implanted side. It feels like the logical thing to do if a patient has existing hearing remaining in the low range would be to get a SHORTER array and not have the array reach the deep end of the cochlea. Then a hybrid system like the Sonnet EAS model could support CI hearing at the high range and acoustic hearing at the low range. 
 

I read there was a university doing implantation with a robot hand (far slower and more delicately than humanly possible). I’m curious if they’ve proved to have any greater retention of acoustic hearing vs human surgeon implantation?

[Mary Beth]

Interestingly I know CI users with shorter arrays who lost their low frequency residual hearing and CI users with longer arrays who still have their residual hearing in the low frequencies years after implantation.  Not a scientific study by any means.  Just an interesting observation.

[Lauren]

6 hours ago, Mary Beth said:

I have been very intrigued by CI users who initially have preserved hearing and use an EAS fitting and then several years later lose their preserved hearing and need to adjust to a full CI fitting.  That transition seems to be very difficult for many people.

I know my case wasn’t exactly typical but I did use EAS for about 17 months in my left ear before my second surgery. I remember doing a blind test and preferring the sound of the CI only but I had slightly better word recognition with the EAS so that’s the only reason I used it. Plus combining EAS in the left with HA in the right for that time made it a little easier. After the second surgery, the trauma to the left ear didn’t retain any residual and the right ear ended up with none as well so that meant no EAS anymore. 

Starting from scratch as bilateral was what was hard. I don’t really miss having EAS and don’t really fell like I’m losing out from not having it anymore. Just glad I was able to at least experience it, however briefly. 

[Evren]

I have some low freq left from my first surgery. I can hear dyson hair dryer, doors shutting, some outdoor motor sounds etc but doesn't make lots of difference. When I vibrate my ear from behind I can hear the vibrance too.

Wasn't that lucky with my 2nd surgery though. (Zero residue)

[John F]

I have Flex 24s.  There’s some residual hearing in the first ear (R) but it’s so minor it’s probably not worth it.  That processor is technically an EAS the doc ordered but never bothered with the ear piece.  The other side (L) simply never had any residual hearing leftover.  As always, research the surgeons and their success at this stuff.  Personally have nothing good to say about mine and the idiocy in both surgeries that went down so YMMV.

[jcech344]

On 5/6/2024 at 3:24 PM, Kilgary said:

My surgeon warned me that even if she placed the array as delicately as possible by human hands, there will be ossification around the array in the months following implantation leading to damage of the remaining hair cells. Sure enough, I lost virtually all my acoustic hearing in my implanted side. It feels like the logical thing to do if a patient has existing hearing remaining in the low range would be to get a SHORTER array and not have the array reach the deep end of the cochlea. Then a hybrid system like the Sonnet EAS model could support CI hearing at the high range and acoustic hearing at the low range. 
 

I read there was a university doing implantation with a robot hand (far slower and more delicately than humanly possible). I’m curious if they’ve proved to have any greater retention of acoustic hearing vs human surgeon implantation?

The university you mentioned is U of Iowa.  Out of that came a robotic aid developed in conjunction with a bioengineer.  The company formed from this is IotaMotion.  [https://iotamotion.com/surgeons/] The "robot" is actually a drive and head that inserts the electrode array at much lower speed (1/10 of what a human can do).  This greatly reduces translocation and trauma by reducing the pressure wave created when the electrode is pushed into a contained space (cochlea).  

I selected a surgeon experienced with this method and had a flex 28 insertion.  You should ask your doctor about this or contact IotaMotion for a list of area physicians certified in this use. For me the use clearly accomplished a successful (location) insertion.

Was it successful in preserving residual hearing which was the whole point?  Initially I believed that I had lost all residual hearing and chalked that up to post op healing and inflammation.  What I could tell however was that I could hear sounds in my head (my pulse, ear pops or even tapping on my ear), but nothing originating outside.  Then wearing a Bose headset, I discovered that I could hear low frequency sounds, not well, but there.  Yesterday at my regular checkup with my CI audi team, they did a pure tone audiometry test on my implanted ear (3 months after surgery), and the audiogram matched the pre-operative one at least through 1000 Hz!

I am now going to try the EAS modification to my Sonnet 2 to see if there is a noticeable further improvement. Honestly I am skeptical, but willing to try.

 

[Mary Beth]

@jcech344

very interesting!  Keep us posted.

Med-El Innsbruck has been working with a company on a robot also.  It drills the opening I believe.  Some early clinical trial reports have been published.

https://www.cascination.com/en/hearo

[Kilgary]

24 minutes ago, jcech344 said:

The university you mentioned is U of Iowa.  Out of that came a robotic aid developed in conjunction with a bioengineer.  The company formed from this is IotaMotion.  [https://iotamotion.com/surgeons/] The "robot" is actually a drive and head that inserts the electrode array at much lower speed (1/10 of what a human can do).  This greatly reduces translocation and trauma by reducing the pressure wave created when the electrode is pushed into a contained space (cochlea).  

I selected a surgeon experienced with this method and had a flex 28 insertion.  You should ask your doctor about this or contact IotaMotion for a list of area physicians certified in this use. For me the use clearly accomplished a successful (location) insertion.

Was it successful in preserving residual hearing which was the whole point?  Initially I believed that I had lost all residual hearing and chalked that up to post op healing and inflammation.  What I could tell however was that I could hear sounds in my head (my pulse, ear pops or even tapping on my ear), but nothing originating outside.  Then wearing a Bose headset, I discovered that I could hear low frequency sounds, not well, but there.  Yesterday at my regular checkup with my CI audi team, they did a pure tone audiometry test on my implanted ear (3 months after surgery), and the audiogram matched the pre-operative one at least through 1000 Hz!

I am now going to try the EAS modification to my Sonnet 2 to see if there is a noticeable further improvement. Honestly I am skeptical, but willing to try.

 

Very cool!  Hope EAS helps expand the range of what you hear through your processor.  Yeah, when I rub my left ear I get nothing.  Human hands + my Flex 26 took away what remained of my acoustic hearing.  

[jcech344]

4 minutes ago, Kilgary said:

Very cool!  Hope EAS helps expand the range of what you hear through your processor.  Yeah, when I rub my left ear I get nothing.  Human hands + my Flex 26 took away what remained of my acoustic hearing.  

Did you have a post surgery CT scan?  I think this is a requirement for ABF. Did it show any translocation (ie placement of the electrode partially into the SV)? That will destroy residual hearing as I believe it results in mixing the endolymph and perilymph fluids that are the basis of natural stimulation.  It does affect the use of the CI though

[Kilgary]

11 minutes ago, jcech344 said:

Did you have a post surgery CT scan?  I think this is a requirement for ABF. Did it show any translocation (ie placement of the electrode partially into the SV)? That will destroy residual hearing as I believe it results in mixing the endolymph and perilymph fluids that are the basis of natural stimulation.  It does affect the use of the CI though

I did for ABF.  Don't see anything in the notes to that effect but it mentions "opacification" which seems to be what my surgeon said would happen:

"There has been left-sided canal wall up partial mastoidectomy for cochlear implantation on the left side. The cochlear implant is coiled within the cochlea. The electrodes of the cochlear implant are seen in the 2 1/2 turns of the left cochlea. There is partial opacification of the residual mastoid air cells. The right temporal bone is normal in appearance."

[Dianna]

Good morning. I was implanted at u of I by their pioneering head dr. Gantz. He told me at the time iota motion had no approval yet. I also received flex 24 and eas system. The procedure was done and I have not seen a medical person since. My audi told me with ci I registered the highest tone ever with ci according to her. 

I can say that all the steroids taken to preserve what ever possible remaining sound was not fun but apparently I still have 10 percent.

Last summer I lost my eas plug for maybe a month and when replaced I can say I could tell a small difference.

I have participated in research testing at 3, 6, 9, 12, 24 months. I dont always get all results but testing indicates 86 percent of normal. I much prefer the sound of implant over hearing aid. 

I constantly feel I am missing bass sounds, and I don't get out much. I was able to attend a musical when in california and enjoyed immensely.

At this point I would never take off the eas as it holds the sonnet in place and lacks "something" when missing, sound-wise. I am a very satisfied medel customer, looking forward to the future with implantation on the other side.

[jcech344]

1 hour ago, Dianna said:

Good morning. I was implanted at u of I by their pioneering head dr. Gantz. He told me at the time iota motion had no approval yet. I also received flex 24 and eas system. The procedure was done and I have not seen a medical person since. My audi told me with ci I registered the highest tone ever with ci according to her. 

I can say that all the steroids taken to preserve what ever possible remaining sound was not fun but apparently I still have 10 percent.

Last summer I lost my eas plug for maybe a month and when replaced I can say I could tell a small difference.

I have participated in research testing at 3, 6, 9, 12, 24 months. I dont always get all results but testing indicates 86 percent of normal. I much prefer the sound of implant over hearing aid. 

I constantly feel I am missing bass sounds, and I don't get out much. I was able to attend a musical when in california and enjoyed immensely.

At this point I would never take off the eas as it holds the sonnet in place and lacks "something" when missing, sound-wise. I am a very satisfied medel customer, looking forward to the future with implantation on the other side.

Quote

I constantly feel I am missing bass sounds.

Interesting statement, because that is one of the arguments from Cochlear and AB for the shorter array - preserve hearing in the low frequency range to provide a richer hearing experience. The risk however is that as hearing continues to decline, the lack of electrode stimulation in that region means that this important frequency range eventually gets lost.  That has always been ME's argument for longer arrays.

I have been puzzled by the lack of data on hearing preservation.  The studies that I have read that look at this have very limited sample pools, are old or use metrics that don't track well to patient's actual experience.  Statement of 10% or even 80% preservation are qualitative measures that lack good benchmarks.  Before my implantation my surgeon said there was a good chance I would loose residual hearing. Why? Placement was where it was supposed to be.  He used a very steady slow robotic device, yet my hearing in the regions where the electrode array is located is gone.  Why?

The audiogram taken this week of my implanted ear shows almost the same profile as my pre-surgery test from 750 Hz down, yet it is clear my natural hearing there is greatly diminished. The only exception is is the range beyond electrode 1 (150Hz).  Is this coincidental? While my understanding of speech has improved markedly with the implant, I have yet to hear why an otherwise text book placement of the electrode would have affectively eliminated natural hearing in the region where it is located. 

[Mary Beth]

@jcech344

Like you, I have been following research reports on residual hearing post CI surgery and also residual hearing 5, 10 years later.

Clinical trials using various drugs administered via the electrode array apparatus during surgery and soon afterwards are interesting reads.

Many things are being explored-

length of electrode array

design of electrode array

steroid use

drugs administered inside the cochlea itself

timing of electrode insertion

robotic drilling of access

robotic insertion of array

soft surgery vs drilled well for internal component

and more

 

Hopefully as research continues clear answers will emerge.

 

However there are many factors of CI use that still defy established understanding like….

-why a long deafened non stimulated ear performs well with a CI

-why some CI users hear music well and others do not

And more

 

To me it seems like there is still a lot to be learned about CIs 

[Dianna]

Oh gosh yes...much more studies. My implant did not go in all the way by hand by a very experienced surgeon. Two are out and a third over stimulates facial nerve. I can tell little somethings are missing, but some days are great hearing days, much better than I have heard in years.

I test with residual hearing in ci ear, 50% in HA ear, but I feel stone deaf with all appliances off. The other night I was awakened by wild flashing in all windows but had to load appliances to hear thunder.

There are papers from university of iowa and others from not that long ago about arrays and such damaging cochlea and surgical/technical advances have VASTLY improved in a short time. I chose med el after reading some of those papers.

[jcech344]

4 hours ago, Mary Beth said:

@jcech344

Like you, I have been following research reports on residual hearing post CI surgery and also residual hearing 5, 10 years later.

Clinical trials using various drugs administered via the electrode array apparatus during surgery and soon afterwards are interesting reads.

Many things are being explored-

length of electrode array

design of electrode array

steroid use

drugs administered inside the cochlea itself

timing of electrode insertion

robotic drilling of access

robotic insertion of array

soft surgery vs drilled well for internal component

and more

 

Hopefully as research continues clear answers will emerge.

 

However there are many factors of CI use that still defy established understanding like….

-why a long deafened non stimulated ear performs well with a CI

-why some CI users hear music well and others do not

And more

 

To me it seems like there is still a lot to be learned about CIs 

Yes there is a lot to be learned and I wonder whether the medical/scientific community is going about it in the best way. I am interested in understanding the effort to analyze and document outcomes in order to better understand the parameters that control improvement. Are patients being included enough in this process?  Are the test used able to identify cause and effects?  The advances in the technology sectors over the past 20 years have been nothing short of astounding.  In the medical field, much less.  

This entire topic of residual hearing and the factors that influence it is one example.  I hear people say you have 10% of 50% or 80% of your residual hearing.  What does that actually mean from a practical point.  I have attached 2 audiograms to illustrate this.  The first was taken 6 months before my surgery showing both ears.  They are similar in drop off.  The second was done on only my implanted ear (L) 3 months after implantation. The purpose was to establish that I qualified for an EAS modification based on my comment that I believed I had some residual hearing in that ear.

Amazing to me was to see that the audiograms are almost the same! In other words my residual hearing looks to be almost the same as the pre-operative hearing.  But it is not.  Using a piano, comparing my perception of sound in each ear shows that while I have e hearing in my left ear, it is dramatically less than my right especially in the low frequency range, even though the audiogram shows them to be similar.  So its clear we are not testing the right thing to understand residual hearing.  I am interested in anyone else's experience.

Scan - Audiology Visit (Generic) - Jun 6, 2023 (1).pdf audiogram L ear 5-7-24.pdf

[Anthony Canada]

@jcech344 I'm from the other end of the spectrum. My hearing was so far gone that the loss of the remaining natural hearing was not a concern. If I had retained 80% of my natural hearing there would have been no measurable impact on my life. If much of the community falls into the same bucket as me it could explain the lack patients included in the process.