Frequency Therapeutics — Hearing Loss Regeneration

[Samir]

To me this unraveled the mystery behind T and H, Liberman could be wrong of course but I heavily doubt it, it's too logical to ignore in my opinion.

Opinions and logic does not account as proof or evidence. We need a Galileo of hearing, not another Aristotle. With that said, Charles Liberman has definitely presented some very convincing hypothesis. He is one of the most prominent researchers in this field, and we need more people like him. We will know if these hypotheses are confirmed or not when we start collecting and analyzing data from clinical trials on humans.

We will also need new tools to make comparisons before and after therapy. Non-invasively! Simple audiograms will not be adequate. If we don't get these tools in time, we might as well start believing in magic! If the therapies work well, we will not know for sure why they work. At least I am of the opinion that seeing is believing!

 

[Samir]

How would you explain when some people lower or diminish T when they use hearing aids?

What kind of hearing aid? You mean those that mask the tinnitus? Or those that amplify sounds? Can you give example of people who had their tinnitus diminished by using hearing aid? Also, did the effect last long after hearing aids were removed?

One way I can think of hearing aids improving tinnitus might be by improved frequency discrimination. This might be possible by increasing stimuli to hair cells adjacent to the damaged hair cells. But I doubt this would help much if the underlying cause of tinnitus is synaptopathy. Either way, this would hardly make a lasting effect when the hearing aids are removed. It would require the use of hearing aids all the time.

As long as there are no tools to assess cellular damage in the cochlea, non-invasively and in vivo, everyone is working under assumptions and in the blind. Including the hearing aids companies. They might have "advanced" hearing aids, but they don't quite know why they are working, if they are working.

I am strongly opposed to use of hearing aids. If they work for someone, that's fine, they should have it. But the very concept of hearing aids seems like violating the cochlea. It just doesn't speak to me. Cochlear implants are very different. These are in my opinion the only true remedy for hearing loss currently available in the field of hearing restoration. It's unfortunately only available to those with severe or profound hearing loss. Fortunately I should say! Because those with mild to moderate hearing loss should have a better chance of having their hearing restored by the new promise of regenerative medicine.

Simply put, the field of ear and hearing is almost entirely lacking medical treatments. There is very little that can be done here, even for problems of the middle ear. When you read about it you would think that inner ear problems are the only problems, and that they by now can treat everything else concerning the outer and middle ear. It's not true. It really is a field of unmet medical needs, especially for the inner ear, but not limited to the inner ear.

 

[spingee]

What kind of hearing aid? You mean those that mask the tinnitus? Or those that amplify sounds? Can you give example of people who had their tinnitus diminished by using hearing aid? Also, did the effect last long after hearing aids were removed?

One way I can think of hearing aids improving tinnitus might be by improved frequency discrimination. This might be possible by increasing stimuli to hair cells adjacent to the damaged hair cells. But I doubt this would help much if the underlying cause of tinnitus is synaptopathy. Either way, this would hardly make a lasting effect when the hearing aids are removed. It would require the use of hearing aids all the time.

As long as there are no tools to assess cellular damage in the cochlea, non-invasively and in vivo, everyone is working under assumptions and in the blind. Including the hearing aids companies. They might have "advanced" hearing aids, but they don't quite know why they are working, if they are working.

I am strongly opposed to use of hearing aids. If they work for someone, that's fine, they should have it. But the very concept of hearing aids seems like violating the cochlea. It just doesn't speak to me. Cochlear implants are very different. These are in my opinion the only true remedy for hearing loss currently available in the field of hearing restoration. It's unfortunately only available to those with severe or profound hearing loss. Fortunately I should say! Because those with mild to moderate hearing loss should have a better chance of having their hearing restored by the new promise of regenerative medicine.

Simply put, the field of ear and hearing is almost entirely lacking medical treatments. There is very little that can be done here, even for problems of the middle ear. When you read about it you would think that inner ear problems are the only problems, and that they by now can treat everything else concerning the outer and middle ear. It's not true. It really is a field of unmet medical needs, especially for the inner ear, but not limited to the inner ear.

I read it few times here and on hearing aid forum. Its becouse some type of tinnitus is probably from wrong brain interception of lost sounds, so if you get them back, your tinnitus can be lowered.

Hearing aids are best solution for mild-to-moderate trough to severe losses, cochlear implant is very bad sound wise and their invasive surgery can damage other nervers like facials, its just last resort, also if you get implant you cant ever restore that inner ear when regenerative aproach shows up.

But yeah world really needs inner ear regeneration.

 

[RB2014]

I am one of those people that have benefited from hearing aides. I have posted this several times on this forum. Hearing aides help to recover the lost frequencies you are missing and make things sound as they should. By amplifying the frequencies that are lost the brain does not miss them so T does not appear. It was wearing hearing aides for 20 plus years that kept my tinnitus at bay. Eventually though because of a bout with anxiety my T surfaced.
My brain is plastic. I regularly put my hearing aides in and my T goes to a 1. When I take them out 5 min later it goes to a 6. If I put them back in my T goes to a 1.
There are many types of T for many different reasons. This may not work for everyone, but I believe it will work for anyone that has lost hair cells without any other underlying reason for having T.

Lets keep this thread to Frequency Theraputics and their trial if possible. thanks.

 

[swc5150]

I've mentioned it as well. Our band's crew chief has pretty bad T, which goes to 0 when he puts in his hearing aids. His hearing loss came from a night we rented our PA to the 80's band Warrant, who ran their stage gear at 11.

 

[Samir]

Its becouse some type of tinnitus is probably from wrong brain interception of lost sounds, so if you get them back, your tinnitus can be lowered.

Wrong perception of lost sounds? How can there be any perception at all if the sounds are lost? Isn't that what we call tinnitus? Perception of sound without external source. It is not because we perceive these sounds the "wrong" way that we have tinnitus, it's because we do not perceive them at all, due to some damage in the cochlea.

How can you get back lost sounds/frequencies? Without treating the underlying cause, i.e. regenerating synapses and hair cells?

cochlear implant is very bad sound wise

And hearing aids are not? Or is that because hearing aids don't do much at all for your hearing if you have a mild hearing loss so you don't notice the difference?

Hearing aides help to recover the lost frequencies you are missing and make things sound as they should.

You don't lose frequencies, you lose synapses and hair cells. These synapses and hair cells correspond to certain sound frequencies. Hearing aids can't recover lost synapses and hair cells.

By amplifying the frequencies that are lost the brain does not miss them so T does not appear.

You can't amplify lost frequencies, that would mean making dead cells detect more of the sound. That's not how it works.

It was wearing hearing aides for 20 plus years that kept my tinnitus at bay.

So you had T for 20 years? And you were able to manage it with hearing aids? But what happened in 2014? Why would anxiety cause T? I know I had anxiety right before I noticed for the first time that I had T. I think these anxiety episodes are precursors to tinnitus and they are due to recent synaptopathy or hair cell loss.

Can you still manage T with hearing aids?

 

[JRchief]

It's also entirely possible to lose both from an acoustic trauma so in summary,

-Normal hearing loss without T is haircell loss with no damage to underlying neurons

-T and H are a result of damage to these underlying neurons or synaptopathy

-The two can happen independently or occur alongside one another

To me this unraveled the mystery behind T and H, Liberman could be wrong of course but I heavily doubt it, it's too logical to ignore in my opinion.

so how would this relate to me where my T basically goes to a zero by wearing protective ear muffs? i have hearing loss at 8k hertz and above and none below. my T is mild but i feel its related to my hearing.

 

[spingee]

Wrong perception of lost sounds? How can there be any perception at all if the sounds are lost? Isn't that what we call tinnitus? Perception of sound without external source. It is not because we perceive these sounds the "wrong" way that we have tinnitus, it's because we do not perceive them at all, due to some damage in the cochlea.

How can you get back lost sounds/frequencies? Without treating the underlying cause, i.e. regenerating synapses and hair cells?

And hearing aids are not? Or is that because hearing aids don't do much at all for your hearing if you have a mild hearing loss so you don't notice the difference?


You don't lose frequencies, you lose synapses and hair cells. These synapses and hair cells correspond to certain sound frequencies. Hearing aids can't recover lost synapses and hair cells.


You can't amplify lost frequencies, that would mean making dead cells detect more of the sound. That's not how it works.

So you had T for 20 years? And you were able to manage it with hearing aids? But what happened in 2014? Why would anxiety cause T? I know I had anxiety right before I noticed for the first time that I had T. I think these anxiety episodes are precursors to tinnitus and they are due to recent synaptopathy or hair cell loss.

Can you still manage T with hearing aids?

You dont lose frequencies just sensitivity to them

 

[Samir]

The way hearing aids work is they amplify certain frequencies. If you have a cellular damage corresponding to 4500 Hz in the cochlea, amplifying that frequency alone will not help you hear that frequency better. If these cells are dead, they are dead. There is no way around that fact. Except regenerating them! But we are still not there yet.

What hearing aids do is they amplify sounds at 4400 Hz and 4600 Hz. Assuming that the cells surrounding the 4500 Hz region have survived, they will get extra stimulus and thereby increased signal strength. This is supposed to help the brain make up for the loss at 4500 Hz. The brain is supposedly smart enough to fill in the gap at 4500 Hz using the input from 4400 Hz and 4600 Hz. The way this might work is if the frequency band is wide enough at 4400 Hz and 4600 Hz so that the brain may differentially extrapolate the 4500 Hz sounds.

I doubt that it sounds anywhere near as good as having the sensory cells and synapses at 4500 Hz biologically restored. Also, if you have too many of these gaps in the cochlea or if they are too far apart, I don't think hearing aids will help you much. A deaf person for example has no use of hearing aids because there is nothing to amplify! No sensory cells!

That's one advanced brain! Brains are indeed very advanced, but I don't think hearing aids are good enough in the long run. Putting extra stress on surrounding cells can't be good for cell survival. We can do better! Much better! Especially now that we know so much more about ears and hearing! We should not be satisfied with this and allow the hearing aid companies to set the standards.

Companies like Frequency Therapeutics are seeking biological answers to the problem. But they are not only up against biology, but also the establishment. Hearing aid and cochlear implant is a billion dollar industry. These companies will not look kindly on anything that disrupts their cash flow. They will want to push back these new approaches to treating hearing loss and deafness so that they have enough time to further advance their own technology and stay competitive.

 

[Samir]

so how would this relate to me where my T basically goes to a zero by wearing protective ear muffs?

Yeah! I thought about you! It's hard to think that your T would disappear when you put ear muffs on. I think for most people it's the other way around.

You dont lose frequencies just sensitivity to them

I would say you can lose frequencies if the gaps between dead and healthy hair cells are too wide. How do you explain naturally occurring upper range frequency loss from 10000 Hz to 20000 Hz (Presbycusis)? Loss of sensitivity or loss of hair cells and synapses?

 

[GregCA]

The way hearing aids work is they amplify certain frequencies. If you have a cellular damage corresponding to 4500 Hz in the cochlea, amplifying that frequency alone will not help you hear that frequency better.

You don't necessarily completely lose the ability to hear at a given frequency. Often times you just lose a fraction of your ability to detect sound at that frequency.

That's what you measure with a hearing test. If you get a threshold of 40 dB at 1 kHz it means that you haven't lost all the ability to hear 1 kHz, but you need that frequency amplified by 40 dB to make it "sound like normal" again.

If hearing a frequency was exclusively binary you'd have very weird looking audiograms zig-zagging all over the place.

In many cases, you still have enough cells, synapses, and whatever else is required in the pipeline to hear the frequency range partially. We may not know the details of how and why it happens, but the tests are repeatable, consistent, and do show that it happens.

 

[lapidus]

so how would this relate to me where my T basically goes to a zero by wearing protective ear muffs? i have hearing loss at 8k hertz and above and none below. my T is mild but i feel its related to my hearing.

It's very strange indeed. My wild guess would be that you have very mild "normal T" but an extremely severe "reactive T" component to it.

 

[Samir]

You don't necessarily completely lose the ability to hear at a given frequency.

Thanks to healthy surrounding cells.

Often times you just lose a fraction of your ability to detect sound at that frequency.

Due to loss of cells at that frequency or very close to it.

That's what you measure with a hearing test. If you get a threshold of 40 dB at 1 kHz it means that you haven't lost all the ability to hear 1 kHz, but you need that frequency amplified by 40 dB to make it "sound like normal" again.

A 1000 Hz tone does not exclusively stimulate the 1000 Hz section of the cochlea. It rather stimulates a range of frequencies in the cochlea, perhaps from 900 Hz to 1100 Hz. You perceive this as a 1000 Hz tone, even if you have missing hair cells at exactly 1000 Hz. This is possible because the brain is smart enough to predict the highest peak to be at 1000 Hz by using the information from the surrounding hair cells. A 40 dB hearing level at 1000 Hz is like a mean average hearing level for frequencies ranging from 900 Hz to 1100 Hz, centered at 1000 Hz.

If hearing a frequency was exclusively binary you'd have very weird looking audiograms zig-zagging all over the place.

Well it's not binary. One reason is because outer hair cells are innervated by spiral ganglion neurons in bundles of 15 or more hair cells. For 1 neuron you have 15 outer hair cells. That's not binary (in the sense of one on one correspondence)! I am not even accounting for the inner hair cells. The second reason is the way that fluid/mechanical waves propagate inside the cochlea. This is all the more reason why the cochlea is such a complex organ.

There is no reason to believe that there is a one on one correspondence between test tone pitches and the cochlea. This is exactly why you don't see the graph zig zagging (unless you have severely damaged cochlea). The audiograms show mean average hearing levels at pitches one octave apart: 250, 500, 1000, 2000, 4000, 8000 (plus the half octave 6000) Hz. That's why we don't need to do the test with 1 Hz increments to get an idea of the hearing level. Such test would take at least two hours to complete, if not more. If you were to do such a tedious test you might see the kind of zigzag graph you describe.

In many cases, you still have enough cells, synapses, and whatever else is required in the pipeline to hear the frequency range partially.

Frequency ranges, yes. But also discrete frequencies, with the help of surrounding healthy cells within the range. In other words, if all your cells and synapses are dead at 1000 Hz, you will still be able to perceive 1000 Hz tones if your hair cells 100 Hz below and 100 Hz above that are healthy and alive. This way you can hear all the frequencies in the range 900 Hz to 1100 Hz. But you will have the classic "dip" at exactly 1000 Hz.

The "dip" is more or less evident on the graph, i.e. more or less shallow and sharp. The deeper and sharper the dip, the more severe the damage is at that test frequency. But this can be elusive. The dip can be shallow and dull. So it depends on the sampling of the test. You need more sampling frequencies and more sampling points to tell how far-spread the damage is at the cochlea. The standard hearing test consists of 7 sampling frequencies. You will need more than that. The standard hearing test is a good gauge for overall hearing level. But it cannot serve well as a way to assess this kind of granular hearing discrepancies and to give us detailed information about the cellular damage in the cochlea.

A visual tool, such as a µOCT endoscope would serve that purpose much better. Not to mention how much faster we could assess the damage, compared to doing insane 1 Hz increment audiometry. A visual instrument like that is something we are currently missing in the clinics.

The last point I want to make is that if the range at which you have cellular damage is wide enough, you will not be able to hear certain frequencies within that range, least of all the mid frequency. If the cells corresponding to the range 500 Hz to 1500 Hz are all dead, I bet you can't hear a 1000 Hz tone! As you get closer to the endpoints of that range you may start to hear some tones. So you may be able to hear the 800 Hz tone, as well as 1200 Hz tone, but maybe only after increasing the volume to 50 dB. At the very endpoints you would most certainly be able to hear the tones, assuming you don't have any other damaged segments below 500 Hz or above 1500 Hz. So you may hear the 500 Hz tone, perhaps at mild to moderate 30 dB level.

We may not know the details of how and why it happens, but the tests are repeatable, consistent, and do show that it happens.

Not sure what to make of this... how or why what happens? I may have already answered this... if you're referring to why we still can hear certain frequencies at some level, even after damage to the hair cells or the synapses in a certain region of the cochlea.

 

[GregCA]

Thanks to healthy surrounding cells.

Yes and that's the point of the hearing aid. When you have a 50 dB loss at 4 kHz, the hearing aid doesn't just boost 4 kHz by 50 dB and leave all of the other frequencies around it untouched: the gain curve shows an elevation around 4 kHz with a gain greater than one in its surroundings.
The point of that gain curve is to get to the patient a perception of 4 kHz (and surroundings) identical of what the patient would have if it didn't have any loss.

There is no reason to believe that there is a one on one correspondence between test tone pitches and the cochlea. This is exactly why you don't see the graph zig zagging (unless you have severely damaged cochlea).

Well there is a map between frequency and region of the cochlea, so there is a map between the test tone pitches and regions of the cochlea, by definition. The tonotopical arrangement of the cochlea is well documented.
I don't see what zig-zagging has to do with that.

The audiograms show mean average hearing levels at pitches one octave apart: 250, 500, 1000, 2000, 4000, 8000 (plus the half octave 6000) Hz.

I don't disagree, except for 6000 Hz being half an octave above 4000 Hz...

If you were to do such a tedious test you might see the kind of zigzag graph you describe.

Maybe, but I'm not so sure, because of the very mechanism you describe, where nearby cells help "fill in" for dead ones.

The last point I want to make is that if the range at which you have cellular damage is wide enough, you will not be able to hear certain frequencies within that range, least of all the mid frequency. If the cells corresponding to the range 500 Hz to 1500 Hz are all dead, I bet you can't hear a 1000 Hz tone! As you get closer to the endpoints of that range you may start to hear some tones. So you may be able to hear the 800 Hz tone, as well as 1200 Hz tone, but maybe only after increasing the volume to 50 dB. At the very endpoints you would most certainly be able to hear the tones, assuming you don't have any other damaged segments below 500 Hz or above 1500 Hz. So you may hear the 500 Hz tone, perhaps at mild to moderate 30 dB level.

Sure, but that is quite off topic. I'm not so sure why you went ahead and wrote so much stuff about hearing in general (much of which I don't disagree with).
Your original quote was:

The way hearing aids work is they amplify certain frequencies. If you have a cellular damage corresponding to 4500 Hz in the cochlea, amplifying that frequency alone will not help you hear that frequency better.

And the point I was trying to get across to you is that hearing aids never simply amplify that frequency alone. They amplify the surrounding frequencies such that the patient "feels" the improvement at 4500 Hz.

 

[jacob21]

I was wearing hearing aids ( widex ) for 7 years and same as Rb2014 :
It was wearing hearing aides for 20 plus years that kept my tinnitus at bay. Eventually though because of a bout with anxiety my T surfaced.
My brain is plastic. I regularly put my hearing aides in and my T goes to a 1. When I take them out 5 min later it goes to a 6. If I put them back in my T goes to a 1.

BUT since June 2016 , My T frequency changes from 6 k to 9 k I would say . And unfortunately now the HA doesn't help anymore

I tried different brands and setting but I am not able to have the same result as before .Now my T is always at 6/7 except some days at 1 ( I don't know why )

IF someone have a clue or a suggestion , it is welcome

And of course waiting for some news from Frequency Theraputics trial result ...

 

[RB2014]

Jacob21. PM me directly and lets talk.

I'm still serious about signing up for the trial which is why I started this thread. Same here waiting patiently for any new info on Frequency Theraputics.

 

[Samir]

Yes and that's the point of the hearing aid. When you have a 50 dB loss at 4 kHz, the hearing aid doesn't just boost 4 kHz by 50 dB and leave all of the other frequencies around it untouched: the gain curve shows an elevation around 4 kHz with a gain greater than one in its surroundings.
The point of that gain curve is to get to the patient a perception of 4 kHz (and surroundings) identical of what the patient would have if it didn't have any loss.

Agreed!

Well there is a map between frequency and region of the cochlea, so there is a map between the test tone pitches and regions of the cochlea, by definition. The tonotopical arrangement of the cochlea is well documented.

Agreed!

I don't see what zig-zagging has to do with that.

What I mean here is that you might see a very different graph if you sample more than the standard 7 frequencies. You might see more than only one sharp rise and fall in the graph, i.e. zigzags. We get back to your binary analogy. (Never thought I would use the word binary and analogue in the same sentence.)

I don't disagree, except for 6000 Hz being half an octave above 4000 Hz

D'oh! Perfect fifth?!

Why do we even have that odd boll in there? All the other frequencies are one octave apart.

Maybe, but I'm not so sure, because of the very mechanism you describe, where nearby cells help "fill in" for dead ones.

Fair point! But we can't know for sure until we test that. It would be interesting to see how that works out, just as an experiment.

And the point I was trying to get across to you is that hearing aids never simply amplify that frequency alone. They amplify the surrounding frequencies such that the patient "feels" the improvement at 4500 Hz.

Aha! So we are on the same page then?! And here I am wasting digital ink on trying to convince you in something you already agree on. Sorry! I completely misinterpreted you.

Funny how my smiles smack their heads in sync!

 

[Samir]

I just have to say I am surprised that so many of you were helped by using a hearing aid. Using hearing aids to boost hearing thresholds is one thing, but using them to effectively lower tinnitus is something I did not expect. This is a significant finding. It further strengthens the hypothesis that tinnitus is caused by loss of sensory cells and/or synapses.

But it also seems like those who previously found relief by using hearing aids are now faced with the problem that hearing aids no longer help them. Could this be because of new sensory/synaptic loss? How can hearing aids be reconfigured to make use of another set of healthy cells?

Of course, we can't just keep reconfiguring hearing aids and wearing down another set of healthy cells. We need to be able to bring new cells to life. This is of course something we all strive for. Hopefully this will all change when Frequency Therapeutics and other companies like it have a treatment ready!

 

[GregCA]

What I mean here is that you might see a very different graph if you sample more than the standard 7 frequencies.

Certainly! Just like any function, the more sample points you have the more details you are going to get, including "spikes and crevasses" that weren't visible with a lower sampling rate.

D'oh! Perfect fifth?!

Why do we even have that odd boll in there? All the other frequencies are one octave apart.

Good question and I don't know the answer. I haven't seen it on all audiograms though. Some skip 6 kHz, while others don't. I haven't found a pattern to it.

Fair point! But we can't know for sure until we test that. It would be interesting to see how that works out, just as an experiment.

Our testing methodology is currently a black box that doesn't really tell us the "how". It may tell us the "what" as in "your threshold at 4 kHz is 50 dB", but it doesn't tell us how it happens. Is it nearby hair cells helping out? is there some amplification layer somewhere downstream? Until we get better at understanding our hearing apparatus, it's going to be educated guesses. And yes it would be very interesting indeed, I agree.

 

[Cam Cam]

I just have to say I am surprised that so many of you were helped by using a hearing aid. Using hearing aids to boost hearing thresholds is one thing, but using them to effectively lower tinnitus is something I did not expect. This is a significant finding. It further strengthens the hypothesis that tinnitus is caused by loss of sensory cells and/or synapses.

But it also seems like those who previously found relief by using hearing aids are now faced with the problem that hearing aids no longer help them. Could this be because of new sensory/synaptic loss? How can hearing aids be reconfigured to make use of another set of healthy cells?

Of course, we can't just keep reconfiguring hearing aids and wearing down another set of healthy cells. We need to be able to bring new cells to life. This is of course something we all strive for. Hopefully this will all change when Frequency Therapeutics and other companies like it have a treatment ready!

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0051915 < here's a study in regards to hearing aids and T. It's pretty obvious Tinnitus is caused by loss of sensory hair cells/synapses. I don't see how it's not, I never had T or H 6 months ago and now I have noticeable hearing loss. My music sounds different. It's pretty fucking obvious that hearing loss causes T and H. People always rave on about different forms of Tinnitus like how they've had a massive knock to the head and woke up with T. Are they sure they just didn't suffer hearing loss from this knock? Some people get T after a car crash....well a car crash is pretty fucking loud.

 

[Aaron123]

Isn't this a thread about frequency therapeutics? There are other threads about hearing aids.

 

[Cam Cam]

Isn't this a thread about frequency therapeutics? There are other threads about hearing aids.

Was about to say this as well. Thank you. Samir take the hearing aid talk elsewhere!

 

[Samir]

It was about Frequency up until about 20 posts back. Then it derailed into hearing aids. So let's bring this train back on track.

What can you tell me about the delivery method that Frequency plans on using?

Frequency will use a clinically established procedure to inject small molecules in a slow-release gel into the middle ear during a three minute office procedure. Intra-tympanic injections are widely used for steroids in a high volume ENT procedure under an existing CPT code.

Do they make an incision in the tympanic membrane? Or they just push the needle through it? They release the molecules at the round window? Then what? How are these molecules taken up through the round window membrane? Several companies seem to plan on using this technique but I found no detailed explanation of how this works.

 

[Samir]

I think they will need to make an incision, because they probably need to see into the middle ear and aim for the round window. I don't think they can do that without putting in an endoscope through the tympanic membrane, along with the syringe.

The concept behind this delivery method is something called diffusion. The round window is semi-permeable which means it can allow molecules to pass through it. This is the way ototoxins get inside the cochlea too (amikacin).

 

[Aaron123]

Do they make an incision in the tympanic membrane? Or they just push the needle through it?

I'm not sure what is confusing. The quote in your post indicates that they use an intra-tympanic injection. So they "push the needle through it" just like they do with steroids. As it says in the text you quote, they will use a slow release gel, and as you say the drug will diffuse though the round window into the inner ear. There is no need for an incision or an endoscope.

 

[Samir]

I'm not sure what is confusing. The quote in your post indicates that they use an intra-tympanic injection. So they "push the needle through it" just like they do with steroids. As it says in the text you quote, they will use a slow release gel, and as you say the drug will diffuse though the round window into the inner ear. There is no need for an incision or an endoscope.

I thought they needed a visual guide to facilitate contact with the round window. So it's enough to just tilt your head and the gel itself will facilitate contact with the round window? What is this gel made of? How effective is round window access? Can the drug reach out to all regions of the organ of Corti this way?

 

[Mricha37]

I thought a company already has a patent on the delivery system of medicine to the inner ear?

 

[Samir]

@Mricha37 What company would that be?

I have been reading about this today. Apparently, the way of using syringe injections through the tympanic membrane has been in use since the 1940s. I don't think anyone can have a patent on this. What they might have patent on is the gel, and of course the drug itself.

 

[Reinier]

I was somewhat surprised that GenVec makes a little hole in the cochlea with a laser to get the drug in.
What will this laser damage in the inner ear?
I always figured that a slow releasing gel on the round window was an effective way of getting drugs in the inner ear.
Perhaps not (yet?).

 

[Samir]

There is a company called Auritec Pharmaceuticals that focuses specifically on drug delivery mechanisms.

Auritec Pharmaceuticals looks for diseases or indications that have good drugs on the market, however the drugs have problems with their delivery. We are interested in safe and effective drugs that are nearing patent expiration and could benefit from an alternate delivery route.

Source: http://www.auritecpharma.com/indications/

But they currently don't have anything for the inner ear. Which is understandable, since there are no drugs on the market for treating inner ear disorders. @Mricha37 The paragraph above supports this general idea that a company normally has a patent for not only the drug, but also for the delivery system. But in case of inner ear disorders, no one really holds a patent for the delivery system. There is not really much to it, there is not enough complexity to even call it a "system". I guess this is a good thing, because many companies can share the same method, instead of each of them having to reinvent the delivery method.