Inner Ear Hair Cell Regeneration — Maybe We Can Know More

Interesting. Could it be that Tinnitus is caused by malformed interaction between an intact hair cell and damaged synapse as some sort of (electrical) interference? This might for example explain the "reactive tinnitus" phenomena, if the input generated by the intact hair cell sends down increasingly intense signals into the damaged synapse upon stimulation, this might perhaps create the perception of tinnitus which seems to compete with outside noises?

Could it be that when Tinnitus appears to stop for some people after decades, the hair cell is lost due to the normal ageing process, leaving only the damaged synapse and stopping this interference?

Just throwing out some thoughts...

 

I have a hearing test appointment today in 45 mins. The purpose of this test is to see if I have any residual hearing in my cochlear implanted ear. I hoping there is so I can use a hearing aid in my right ear. I hope this works as then I can use aids in both ears and hear more...which means a better life experience, more opportunities. I will report back once I am back home

 

This tread is very interesting indeed. But one thing we really havnt discussed is the outer HC and their part of the deal. Im sure the same mechanisms will apply for these? I think that it is the outer HC that is responsible for H since it is a breakdown of the audiotory pathways filtersystem. Which part do you guys think these HC and their corresponding synapses play in this?

 

Could it be that not the complete cell is dead? Just the protruding stereocilia are damaged? And for that reason synapse can still be there? Also for that reason cochlear implants are possible? That all seems unlikely to me. Surely, with all the experiments on animals this must be known.

 

I read that non working outer hair cells translates in approximately 50-60 dB loss. This is already moderate to severe hearing loss.
I also read that the stereocilia of the outer hair cells change in length for a particular area. This is how we are able to tune out sound and concentrate on a particular sound in noisy environments. I find this pretty amazing.
Inner ear is beautifully evolved. No wonder it is prone to damage. So delicate.

 

Will you be using a hearing aid also in the cochlear implant ear? Interesting to know how you got on.
Lets hope for positive news.

 

This is my loss at 6000 Hz, both sides. Less at 8000 and 4000 (30 to 40dB).
Almost normal at 2000Hz and under. My outer cells are severely damaged but some must remain as I'm not totally deaf in the high frequencies.

I never had an audiogram before my condition got worse this year, I regret it because I can't visualize the link between my hearing loss and T + H intensity.

I'm 30 years old, my hearing was already damaged at 18, but not beyond 20-30dB.

 

I understand the outer hair cells are the first "to go" with NIHL. Perhaps after the hidden hearing loss process )-;

 

Right, just got home. It was quite difficult to hear any sounds such as beeps, wooshing or any sound the audiologist was conducting. This is because my tinnitus is very loud and I feel if there is any residual hearing left, the tinnitus was masking the sounds. I did hear some sounds so pressed the button. Anyway, what we have agreed on is to order an hearing aid for the implanted ear in the hope the hearing test was unworthy due to my tinnitus. If I do hear with the aid, then great. If not, then I won't have to pay for the aid and it will an confirmation I have no residual hearing left in the implanted ear

 

I wonder how could be done a clear display from each damage with current test tools since the amount of damage in each inner ear zone (neural, ciliary) should probably be known the most accurately possible in order to handle the amount of what must be repaired for each person.

 

Outer hair cells are like people on the beach when a tsunami arrives... The first to go
That's how I see a noise insult : as a tsunami.

 

Is Stanford not working on a confocal microscope for the inner ear? If I remember correctly it was for in vivo.

 

Insult indeed.
If you realise how delicate the hearing system is, it is pretty amazing what we do to it.
Just imagine. Sound waves so intense that you feel them with your body.

 

Possibly but from what I've read it just said that a haircell can be lost where as its underlying neurons can remain intact.

 

According to Libermann loss of auditory neurons is responsible for not being able to hear accurately whilst surrounded by noise meaning that our ability to filter out noise is a result of auditory nerve fibers and not OHCs.

 

That's the thing,they're not the first to go and this research kinda confirms that.These synapses are the first to go long before any haircell does,also it's possible to lose nearly all these synapses without losing its connecting haircell just as you can lose a haircell without losing any or very few synapses.I guess it's just a roll of the dice,will it be synapse damage,haircell damage or a mixture of both,but these synapses are much more vulnerable to damage it appears.

 

@Reinier

I just qualified for a Cochlear Implant at a hospital in Toronto Ontario Canada. Who they pick to receive the implant really is quite simple. Must have severe hearing loss in both ears AND be in good health with no other life threatening illnesses. How quickly you qualify is really up to you. You need to have a certified audiology report and a referral from your GP to be seen by the implant team. I lost ALMOST all hearing in 2011, but could still use a hearing aid in my left ear to hear speech etc. In 2015, all hearing was finally gone. No hearing aid could help. It really would only take an average of 5 months from that final loss, to have your first appointment with a Cochlear Implant program coordinator. Took me awhile longer as I wanted to wait for the winter to be over and not have to drive on our busy highways into Toronto. So even tho I had a referral and all the hearing test results, I put it off awhile. Then got a hold of the program directer finally late spring this year and they had an opening for June 2016. That was my initial visit where you meet someone in the team, and they discuss the implant and surgery etc, and talk to you about your hearing loss and if they think the implant would be good for you. If you both feel the implant will be beneficial, and the team feels your health is half decent, you then get an appointment to meet the surgeon about 3 months later. I just finished with my second visit and met the surgeon who will be doing my surgery. He also feels I will make a great candidate and has now placed me on the list for surgery, which can take quite some time to have done due to funding. They receive funding for 120 surgeries per year but the waiting list at this hospital is now just over 200. So do the math. Could be close to 2 years before someone gets the surgery.

In my case, the hearing loss was sudden and severe. It was not a slow loss like many of the patience they now have on the list. They know how drastic sudden hearing loss is on a person as compared to someone who loses hearing over a long period of time and slowly adjusts. They try to bump up people like me faster on the list. They promised they would try to get me in sooner but warned I may only get 48 to 72 hours notice before the surgery. No sweat for me. I'm ready in 3 hours if they want!!!

A little news about the implant. They insert this electrode into the cochlea (inner ear) as part of the implant components. This thin electrode runs all around the snail like cochlea from beginning to end. On this electrode are hundreds of fine wires. Basically fine hairs. When they showed me the actual electrode, it was almost impossible to really see an individual wire. That's how fine or thin they are. The sound from the receiver eventually make it to these wires and your brain interprets them as sound.

 

Also note about Cochlear Implants. The electrode that is inserted can and does cause damage to existing hair cells in the cholera. The implant team try to pick your worst ear for the Cochlear Implant. In my case I can still hear loud bangs, alarms etc in my right ear and have what you call, residual hearing. So the surgeon has chosen to do my surgery on my left ear which is as useless as Al Bundy!!

Eventually I would like to have both ears implanted however funding issues may prevent that and also if I have the other ear done, I may lose the ability to have other treatments that may come up in the future for hair cell regeneration etc. Damn if I do, damn if I don't. hmmmmmmmm

 

So far i know they wipe out all remaining hearing prior to CI operation

 

What about this fancy CI
http://www.audiology-worldnews.com/...ives-fda-approval-on-new-hearing-device-kanso

 

@MikeP505
Thank you for your explanation. Interesting facts.
So there never was talk about a time window. Than can we conclude the neurons and fibres are/remain intact perhaps even indefinitely? Are the tiny wires of the cochlear implant connecting to..... what exactly?

I can understand why people that loose hearing all of a sudden opposed to gradually, are given preferential treatment.
I read your story and hope you will benefit from your cochlear implant.

I think I would make the same decision to look further into the future where it could be possible to regenerate hair cells and restore the non cochlear implant side. Plenty researchers think this will be possible in future. I wonder if regeneration in future is possible after removing the cochlear implant. But perhaps that is being very optimistic.
But to be honest I find it difficult to imagine the impact this level of hearing loss will have on your life.

I like the expression: useless as Al Bundy. Never heard it before.

 

For what I was told, those tiny wires connect to both the hair cells you have in that cochlea AND also touch the inner walls of that cochlea. This is why the implant needs to be tuned frequently when you first receive it. After about 3 weeks of healing from the initial surgery, you go back and they turn you on! They place the receiver over the ear that looks like an over-the-ear hearing aid, and a wire from that unit leads to a magnetic sending unit, that sticks to your scalp magnetically where the inner receiver was installed on the scalp. That inner receiving unit consists of a magnet, and a pack of micro-electronics. Once the signal passes from the sending unit, thru your scalp and into the receiving unit, it goes thru the electronics and up the wire that leads to that electrode installed in the cochlea. So when they first turn it on, and talk to you and test various other sounds etc, they tweak it with a computer until the sounds are more natural. So instead of everyone's voice sounding like Donald Duck, it becomes more human. For some reason, your inner ear is adjusting rapidly over the next few months and you need to go back often to have the sound processor tuned. After a few months things stabilize and you only go back for fine tuning if you yourself deem it necessary. However they always see you at least once a year for the rest of your life and can make adjustments etc.

Trust me when I say this....... you do NOT want to understand the effects of sudden hearing loss has on a person. Then add extremely loud Tinnitus to it!! How I managed to stay sane even in the slightest is beyond me. Then to top it off, no one around you knows anything at all about deafness and tinnitus. So they see you as a normal looking human being who can walk and talk and drive and pretty much function normally, but they don't see the suffering. You lose your job, you go into poverty, you deal with bill collectors in the beginning that adds stress, can't make a single phone call for a doctors appointment or anything, so you must go there in person to communicate, you go shopping and nearly get hit by cars in the parking lot cause you can't hear them coming your way, you become isolated from family and friends cause you just can't hear them, you're out in public and someone begins to talk to you and you must interrupt them and tell them you are deaf.........and they continue to talk to you lol.... just all kinds of life altering crap! Five years ago I was making a good living and no health issues, then boom, you get flipped upside down, claim bankruptcy, lose everything eventually, and struggle to eat from all the stress. You do not ever want to go thru this!

After finding out I was getting the implant last Wednesday, I told my extended family thru emails and text messages. Not a single one of them said congratulations, or way to go, or that's awesome news Mike, or anything positive. So I went from being excited after finding out I qualified, to another frikkin low you can never imagine! Can't really blame them tho, they just do not know what sudden hearing loss and tinnitus is. You really do become isolated and alone in the long run!

 

@MikeP505 Very poignant post.
Empathy seems to be easier when someone has a limp or other noticeable disability's.
On a totally different level I experienced this too. My employer does not accept/understand that I can't be around average sound levels any-more.

You must be excited and very curious about this cochlear implant. I am amazed by the level of technique and possibilities. At the same time I am puzzled why this regeneration research seems to go so slow.
I assume this is just an indication of how complex the task is.

Interesting. This means not all hair cells are lost after implanting a cochlear implant. Also that there is a way that the signal from the implant, not using the hair cells, still end up in the auditory nerve.

 

@spingee

That new Cochlear receiver looks awesome!! Everything is built right into it so you don't need to wear a receiver behind the ear, and no cable leads to the part that magnetically sits on your scalp!! I imagine it would work with any existing implant, as the internal components are the same. I bet since they are new, they are much more expensive. If I wanted to get one of these, I would most likely have to pay the entire cost out of my pocket, and I'm sure it would be around $15,000.

 

@Reinier

You hit the nail on the head. Your boss won't understand, your friends won't, family won't, even your family doctor doesn't fully grasp it. Just not enough awareness. Like I said in a previous post to someone.... I'm glad this isn't 1940's to 1950's, and you told someone your hearing noises. You would be fitted with a nice comfy white jacket and placed in a padded room lol.

 

Couple of my favorite lyrics from the song.... They're Coming to take me away! Enjoy.

And They're coming to take me away Ha Ha
They're coming to take me away ho ho he he ha ha
To the funny farm where life is beautiful all the time and I'll be happy to see those nice men in their clean white coats
They're coming to take me away Ha Ha
To the happy home with trees and flowers and chirping birds and basket weavers who sit and smile and twiddle their thumbs and toes
They're coming to take me away Ha Ha Ha


And They're coming to take me away Ha Ha
They're coming to take me away ho ho he he ha ha
To the loony bin with all you can eat prescription drugs like Thorazine, and lithium, and electric shock and insulin
They're coming to take me away Ha Ha

Read more: Lard - They're Coming To Take Me Away Lyrics | MetroLyrics

 

At least Mike, we are here to tell you it's awesome news. Congrats, keep going !

 

Mike so happy for you, u're an inspiration x

 

We all are struggling with Tinnitus and some even with hearing loss. I know you all understand. Makes posting my thoughts more positive.

Cheers everyone for the kind words and best wishes. I actually can see some light at the end of the tunnel now!!

 

Or Fleeting tinnitus?