cc >> I'm new to UW-Madison.
I've been here for about four years.
I'm a cochlear implant surgeon. I do implants in both adults
and children. I wanted to first take a minute
to thank Ruth, and Theresa --, and Carrie -- who just stepped
out for a minute. It's a joint effort in
organizing this amongst us. January was our first meeting to
think about this meeting and it's a pleasure to see the great
turnout we have today. And after so many months of
thinking about it, I think we're all very pleased.
So thank you all for showing up today.
I hope it's useful in all regards.
I'm going talk a little bit about the medical aspects of
cochlear implantation. I hope to have some time at the
end to speak a little bit about novel therapies for hearing
loss. And no financial relationships.
I will be talking about the different implants, and I have
no relationships to disclose with any of the manufacturers,
while review the devices in brief.
Diane talked, and I'll have a little bit more
than she covered. This is the outline.
I was unaware of how much history and depth Diane would go
in her talk about the history which was wonderful, and so
we can save time by going through the history quickly.
The cochlear implant evaluation. There was a question about the
evaluation itself. What are the facets of the
evaluation process. I'll cover those in detail.
And we'll go over the surgery briefly.
And we'll talk about life after a cochlear implantation.
Briefly some of the nuts and bolts and implications medically
for decisions down the road and talk a little bit about novel
therapies for hearing loss. So I think we can move through
this slide given the crowd and your interests and being here
some of the numbers probably familiar to all of you about how
hearing loss is a global health problem and both in adults and
children. And in general, as Dr. Heatley
covered, if we can use hearing aids, we want to use
hearing aids. It avoids surgery, and uses
normal acoustic hearing than electric hearing that is
provided with cochlear implants. Essentially, the fundamentals of
cochlear implant candidacy for all age ranges are, are they
receiving limited benefit from a hearing aid.
If we can use hearing aids, we should use hearing aids.
Cochlear implants as we've discussed already, and we've
already covered so much in the first few hours of this and
there's going to be large holes in my talk that we've already
gone over. I'll try to move through those.
It's an electrical stimulation of the auditory nerve.
We talked about different manufacturers and the multiple
channels each manufacturer produces.
It's not great evidence that we are able to actually harness the
extra information provided by additional channels from some of
the cochlear implants, and there is, at least in quiet, a
ceiling effect in about 6 to 8 channels I think, with speech.
Essentially beyond six or eight channels, you can't get
additional benefit, at least in quiet conditions, when we are
testing speech. Again, it's stimulation directly
of the auditory nerve. And I think Diane mentioned,
that in 2010 the latest numbers we have, it's about 219,000
people worldwide who have been implanted.
Here's a typical -- internal device.
We'll go over some of the components of the internal
device in a minute. This is a schematic of what the
electrode going into the cochlea looks like.
So again, I'm going to move right through the couple history
slides. I think this one's interesting,
just because it shows the first device Diane mentioned, which
was really this first cochlear implant, is the house
3M device. It was single channel cochlear
implant. It's remarkable the benefit that
patients got from only one channel.
And especially some patients had a remarkable benefit from only
one channel. There was a question earlier
about the need to re-implant. If you implant a child early in
life and the need to re-implant later.
Certainly, the thought is that, with a modern cochlear implant,
it can last a lifetime. There's a technological risk, if
you will, that at some point there's bound be some
improvement that you want to take advantage of going from a
single channel to multiple channels, or in the future
there's investigations going on to look for totally implantable
cochlear implants. At some point will we look at
doing that, and might one consider the risks of additional
surgery to take advantage of those, of the developments in
the future, that may be possible.
But again, this is of historical interest again, being
the original cochlear implants. It's also worth the mention I
think that cochlear implants are fascinating on many levels but
one of the levels is that it's amazing that they work as well
as they do. You think the architecture of
the inner ear and how delicate it is, that we can put in an
electrode and have it function as well in the inner ear it has
is really remarkable, and it's actually telling, when
the cochlear implants first were introduced, there were many very
prominent cochlear implant surgeons world wide who, I
remember one of the famous quotations, "there will be a lot
of advancements in our ability to improve people's hearing but
cochlear implants is not the one."
There were implant surgeons who almost got burned a little bit
because they made an early judgment.
They were surprised at how well the cochlear implants ended up
functioning down the road. Here are the current devices in
use. Again, there are three
manufacturers and they're very similar essentially.
Here's the external device for the Nucleus, or the cochlear
device, the Advanced Bionics, and Med-El.
This is their modern internal implant, with Med-El, and here's
the external for the Advanced Bionics, and again, the Cochlear
Corporation has the most market share world wide and this is the
currently used implant. We'll talk a little bit about
the evaluation process. There's three important
components, three essential components in the evaluation
process. One really stands out as the
most important. We've touched on it multiple
times this morning. That's the audiological
evaluation done by the audiologists in determining what
level of hearing loss we have. This determination is different
for different ages. Young children, as you might
imagine, there are more challenges in determining
exactly is there is any residual hearing there, and if so, are we
better off with hearing AIDS. Whereas in adults it's a little
more straightforward on some levels, although always
changing. The medical evaluation by the
otologist, or cochlear implant surgeon.
Radiological evaluation as well, involving a CAT scan or MRI
scan, some cases a psychological evaluation.
In children, there's other evaluations that are important
to consider when we're evaluating a patient for their
candidacy and how well they'll do in the future.
The audiological evaluation, again, I think Diane touched on
one thought that I think is important to say here.
Really the advantage we get with cochlear implants and really the
magic of a cochlear implant is not really what's done
surgically. The implant procedure is
relatively scripted on some levels.
You need flexibility with young children and for different
anatomical variance, but on the whole, thankfully for us, the
anatomy is pretty constant. Most of the procedures, again,
you know what to expect throughout the procedure.
Really the advantages and advancements and the benefit
that patients receive with cochlear implants is due to
what's done with our audiologists, both evaluating
patients preoperatively and probably more important after
surgery with the multiple visits that they'll have with our
audiologist to optimize the device and it's function.
Again, the candidacy we've already gone over this, so I'll
move through it. We'll have more on this a little
bit later today. Severe profound, sensorineural
hearing loss in both ears. This can be from before or after
the on set of language. This is a determination we're
using less these days, pre- or post-lingual, and limited
benefit from amplification. Again, these are the two most
important considerations. It's just really from there a
question of how do we demonstrate that audiologically
in different age ranges. Another important thing to
highlight is there has to be realistic expectations for the
device. In the family that Ruth
presented, with the parents having 30 years without hearing
loss the expectations for what they might achieve from their
cochlear implants are going to be very different from their
children when they were implanted, that you can expect
they're going to perform at a much higher level than a person
who's had a prolonged period of hearing loss.
Also, we need to speak to the motivation and commitment of the
patient and the family. This is a critical factor for
getting the best outcomes. Assessing this is hard, but
again, there's a lot left in the hands of the patients and we
help guide things as far as the leap of faith not using their
hearing aid in the other ear anymore.
Just focusing on using the cochlear implant, at least for a
period of time, to get their brain, essentially, used
to using the cochlear implant and going away from auditory
hearing, and maybe re-integrating that that down
the road. There's really a commitment and
motivation requirement that we need to at least mention in the
process that's very important. During the medical evaluation,
there are really three major things that we look at,
the cause of the hearing loss, the duration of the hearing
loss, and then hearing aid usage.
You see on the right, a number of the more common causes of
hearing loss. For most of them it doesn't
actually effect necessarily the candidacy of a patient.
There are some that really will, for example, a history of
meningitis will significantly affect what we might expect
after cochlear implant, and certainly if they have gone on
to develop some -- that some patients will after meningitis.
Thankfully this is infrequent. The bottom line is that most of
time the etiology is not necessarily why they lost
hearing, doesn't affect the ability to implant.
Duration of hearing loss helps to predict what the
realistic expectations might be. And hearing aid usage is
very important. For a patient who hasn't had
hearing for ten years but continued to do what they can
with a hearing aid as opposed to a parent who just abandoned
hearing aids for the last ten years after losing hearing.
We might have different expectations after
their cochlear implant. Any history of infections, be
that acute infections or recurrent infections, perhaps
more severe infections that we'll see the of temporal bone,
and middle ear infections. They'll certainly affect some of
the planning we'll do surgically and how we manage the situation.
Thankfully, it's an infrequent consideration.
Any history of surgery, tubes in the ear, fore-infection, and
surgeries for more significant problems, like cholesteatomas,
as I mentioned, or skill-based tumors, will certainly factor
into our decision-making technically, how we do
the surgery. Then, neuro-surgical procedures
that may have been be needed. Patients who have with syndromic
conditions, like neurofibromatosis, or have had
previous surgery in the area, or shunts for hydrocephalis.
These are conditions that we certainly want to factor in as
we're doing the cochlear implant surgery.
None of them would tell us we couldn't do it but would require
some additional planning. And then general medical
clearance for cochlear implantation.
A patient's cardio-pulmonary profile, their heart, lungs,
what state they're in, if they had a previous heart attack or
any other, maybe congenital, heart abnormalities, bleeding
risk, anesthetic risk. And really important is
wound healing. One of the complications that we
can see with cochlear implants are wound related problems.
As with any implant, as Diane mentioned, with a hip or an
implant anywhere implanted in a human body, there are always
risks of infection and other risks that go along with it.
We must really focus on wound healing problems so patients who
are heavy smokers, uncontrolled diabetes, patients on
steroids for autoimmune disease. These are things we'll
need to factor this in and they might change plan our
surgery a bit as far as what we do planning our incision and
some other maneuvers during surgery to help give us
the best chance of wound healing without problems.
So that's the medical evaluation.
Again, we mentioned audiological evaluation, and then last is an
evaluation radio graphically to look either with a CAT scan or
MRI scan and determine if the inner ear looks implantable.
Generally we do a CAT scan and that tells us that the cochlea
is open and looks normal otherwise.
In patients who've never had hearing in an ear, we'll do an
MRI scan. The reason we do that, most
important thing we need to identify with a screening
evaluation is there an auditory nerve present.
Here we see an MRI scan, and a certain technique of doing
an MRI scan that can highlight the nerves.
You'll see this darkened area here is the hearing nerve as
it's traversing from the brain stem and out to the inner ear.
This is the cochlea right here. And clearly we can tell in this
patient there is an auditory nerve present.
We'll use this type of evaluation in some patients,
particularly young children who have never had hearing to
determine if there's an auditory nerve present and determine
therefore if an implant seems a reasonable thing to do.
Most of the time we use a CAT scan in the majority of patients
though, which is a more limited study but still gives us the
information that we need. We also want to account for
inner ear malformations, or other disease in the middle ear
or mastoid bone that may complicate the implantation
process as part of the pre-operative evaluation.
The next step, essentially at this point we've evaluated and
determined that a patient is a candidate, audiologically, the
most important part of the process, and that there are no
contrary indications medically or on their CAT scan to indicate
that we're going to have problems surgically.
From there then, we submit to insurance.
The question came up on who pays for cochlear implants.
That's an important issue. Our criteria for cochlear
implant candidacy on many levels is based upon insurers.
Most of the private insurers base their determination on
who's a candidate based on CMS criteria, you can think
of as Medicare and Medicaid who set standards for the medical
industry as far as when something is paid for and
when it's not. That's very true for cochlear
implants. It's an expensive venture, so
they have strict criteria that we must meet.
When we write the letter for prior authorization we have to
show that they've demonstrated all these certain prerequisite
criteria in order to be implanted.
This process, unfortunately, sometimes is only a few weeks to
hear back from an insurer, sometimes it's longer.
Sometimes there's an appeal involved.
It depends. As Diane mentioned earlier,
we're fortunate in Wisconsin, I think overall we have very good
healthcare coverage and we're more fortunate than many other
communities as far as how much we have to fight in these sort
of battles to get covered for a cochlear implant.
We still have our troubles here and there.
That consideration aside, we have to decide then which ear to
implant, or are we going to pursue implants on both sides.
We also have to decide which device to implant.
Here at UW we carry the Med-El and the Cochlear devices.
Different centers may cover all three, some carry just one
device. But that discussion is
ultimately made, that decision is ultimately made, by the
patient, primarily in discussion with our audiologists about the
different pros and cons of each device.
Many of them are very similar. It does come down on some level
to some bells and whistles, as far as maybe even how the device
appears, the external processors, sometimes guarantees
on the device or a warranty for a period of five years.
One of the companies offers that currently.
Sometimes it endings up being small things which determine
that. Similarly, when choosing which
side, in some patients, it's very clear.
They haven't had hearing in one ear for 20 years, whereas
the other ear they've heard well from and it's slowly progressed
and now they're a candidate. We're going to obviously want to
do the ear that's their better hearing ear because we can
predict they'll do better with a cochlear implant as that nerve
is healthier. In other patients, it's a wash.
Both ears have had a vary similar history and the decision
will be made by their handedness sometimes, are they right or
left handed, and sometimes other small factors which will make
this decision. Again, the pre-surgical
evaluation, we covered most of the main elements, a visit with
the primary care physician often is involved for preoperative
clearance. Diane mentioned that, as with
any surgical procedure, there are risks involved with
cochlear implantation. Device failure is probably one
of the bigger ones we see. It can come in the form of the
device just stopping working all together.
That's what we call a hard failure, where it's just no
longer working at all, or what's classified as a soft failure.
Slowly the device may start malfunctioning on certain
levels. We think there are different
things happening with the device with these two different
types of failures. If you look across the board,
what's the chance you might have a failure with the cochlear
implant? I think reasonable estimates
are somewhere between 1 and 4%. Infection is a risk.
It's probably 1 to 2% at some point in somebody's life that
they could have an infection. Thankfully, most of the time if
there's an infection, it can be treated with antibiotics.
There are some cases where it's severe enough that the device
would have to be removed. We'd wait for the infection to
clear and we'd have to replace the device.
If that occurs, most of the time we can get a successful
re-implantation with a good outcome, but obviously there's
two surgeries involved and antibiotics and so-forth.
That is a risk, as with any device.
Facial nerve stimulation or facial nerve weakness, an
inherent part of placing a cochlear implant is that we have
to be comfortable around, and very close to, the facial nerve.
You may have seen a patient with a stroke and a Bell's palsy
where there's a facial droop. That's the facial nerve.
In cochlear implantation we have to be very close to that nerve.
It's an inherent part of the surgery, so there is risk to it.
Thankfully, it's very uncommon that we have problems with that
nerve, but, again, it's a part of the surgery.
A risk of dizziness is possible, and more common if a patient has
had dizziness before implantation.
And as I spoke to earlier, there's a technical kind of risk
involved. The patients who got the
original house 3M device, when the multi-channel device
became available, they wanted to have that, so that was a
number of re-implants that occurred.
The same thing might happen in the future.
The surgery itself is done under a general anesthetic.
It's an overnight stay in the hospital.
Sometimes, it's done as an outpatient procedure.
It depends patients to patient. It can be about two hours
on average. There's really minimal hair
shaving for the incision that's involved.
It's all done under a operating microscope that looks like this.
This is one of the monitors, a facial nerve monitor,
that I just mentioned that we use during the surgery.
There are multiple different types of incisions we use, but I
would say this is probably the most common one.
This the patient and their nose is up here, the top of the head,
the feet up this way here's the back of the head.
This is with the ear folded forward and there's an incision
like this, what we call a lazy-S incision, behind the ear.
It's probably the most common. Here's what the device looks
like and the essential components of a
cochlear implant. This is the brains of the
internal-- this is the part that's completely implanted
underneath the scalp. This is the receiver stimulator
where most the important processing of the device
goes on. This coil right here is the
cochlear electrode that gets inserted into the cochlea.
You can see this particular device coils upon itself.
Doesn't come like that, it comes straight when we take it out of
the box but when we put it in the cochlea, it coils
upon itself. Here's another electrode we have
to put under some of the muscle here.
There's a magnet here in the middle of this part of the
device, and that's to help hold on the external portion of the
device which I'll get to that in a minute.
And this is an antenna, which you can think of as essentially
receiving the power and sound signals from the external device
that are transmitted through the skin.
The surgery itself, I'm not going to spend a lot of time on,
but essentially after the incision, if you feel behind
your ear the lump of bone right behind your ear, we have to
remove a bit. That's called the mastoid
process. We have to get though that to
get deeper down to where we're at the opening of the cochlea
and we can make what's called a cochleostomy.
This is a critical part of this surgery, what's called a
facial recess, where we're closest to that facial nerve.
Again, it's key that, for a successful outcome, that
we're very close to it and also respect it, obviously.
The facial nerve runs right in there and we're within fractions
of a millimeter of it during surgery.
Here's the view we have when we're about to make--
This is the innermost of the three hearing bones, the stapes,
here's what's called the round window, and we make a
hole into the cochlea right here, what's called a
cochleostomy, and then insert the electrode.
Here's a picture of a small burr, small drill that we use to
make the hole prior to implanting an electrode into the
ear. After surgery, there's a number
of important things involved. There's a dressing that's on for
a day or two. Immunization Diane covered.
The CDC has recommendations that change periodically.
The last revision was in 2010 with new recommendations for
vaccination for patients with cochlear implants.
Essentially there's one bacteria that we're most concerned about
with cochlear implants and most people now are immunized for
this particular bacteria, but there are new vaccines
coming available. It's important part of what we
do to search people's vaccination records and make
sure that we're adhering to the standards set forth by the CDC
for cochlear implantees. As there is a higher risk of
meningitis in somebody who has a cochlear implant than somebody
who doesn't. Although, it's certainly much,
much lower than it once was even about 10 or 15 years ago.
After surgery there's minimal restrictions as far as the kind
of standard things as far as an incision would go.
There's a one month period where we're allowing the wounds to
heal up after surgery, and then there's multiple visits with our
audiologist over the next 6 or 12 month period.
After that there's annual electrode checks and re-mapping
visits with our audiologist. Should there be any problems
with the device or the wound obviously, there's medical
attention that we re-connect and address any issues that may come
about. Here's the external device,
here's the magnet on the outside as I spoke of earlier helps to
hold this part of the device directly opposed underneath
the implanted portion of the device.
Here's the coil or external antenna.
The microphone of this device is right up here and this
is the speech processor. This is the part of the device
that Diane was showing. Initially it was a box this size
with the giant microphone and now it's been miniaturized
to this. In the next five to ten years,
it's likely we have a completely implantable device.
That's probably, to one question that came up, and that's
possible in the next five or ten years.
There's significant challenges to overcome with regard to the
microphone that we need to address, but that's an on
horizon and an active area of interest as well.
What is it like? This is most appropriately
covered by the panel that we're lucky enough to have
this afternoon. But number one, the sound
quality is different with a cochlear implant than it is with
acoustic hearing. As with a hearing aid, there's
challenges with batteries and recharging the device and
changing batteries, and that's part of having a
cochlear implant. Most patients who have a
cochlear implant will use it most of the time.
That's not true for everyone. Most of the studies generally
show that patients who get a cochlear implant use it.
There are occasional problems with externals.
They can be damaged or if they happen to drop into the sink or
something like that they need to be replaced.
That we'll have to help patients work through.
There are some implications after a cochlear implant, for
you and your healthcare, essentially.
Number one is if somebody needs an MRI scan, they have to have
the magnet part of the device removed and that requires a
separate incision. One of the devices is MRI
approved. Unfortunately the MRI scanner
that we use is really not a modern MRI scanner.
For all intents and purposes, if you have to have a MRI scan
after a cochlear implant, a surgery will need to be
required to remove the battery, have the MRI scan, and replace
battery-- I'm sorry, not the battery,
the magnet. I apologize.
Have your MRI scan and then replace the magnet afterwards.
It can be done very safely, but obviously there's an additional
infection risk with each surgery.
There's also an implication for other procedures you might have.
One of the tools we use enterontively, surgically, can
damage a cochlear implant. So any surgeries that one may
have after a cochlear implant, the surgeon needs to know that
there's one present. What's that?
One minute, okay. I'm running out of time
here. Well, I think-- I did want to
get to a couple of things and I may run over.
Five more minutes, great. We were going to talk a
minute about predicting cochlear implant outcomes.
I think we're going to cover this later in some of the talks
so I'm going to skip through a couple of these.
I wanted to show here briefly the hybrid cochlear implant.
Moving on a little bit to novel therapies in the
future. Ruth talked about the hybrid
cochlear implant, which combines a hearing aid in a cochlear
implant. It's an electrode to stimulate
the high frequencies and then one continues to use hearing aid
for the middle and low frequencies.
Diane mentioned there's not a lot that has changed for
cochlear implant surgery through the years, but one of the big
pushes surgically in one of the finesse part of cochlear
implants is trying to preserve any residual acoustic hearing
that's present. If there's a little bit of
residual low frequency hearing, and certainly essential to this
strategy of a hybrid cochlear implant is how atraumatic, or
how delicately, we can do the surgery and place the implant so
as not to destroy any residual hearing that may be there.
I'd say that's one of the biggest developments surgically,
is trying to prefect our techniques into preserving
hearing. This is a picture of the hybrid
device. Here is the external device for
it, which looks just like a cochlear implant otherwise, but
here is the hearing aid component of it.
We were involved in a clinical trial, not as involved as we had
hoped to be as we were a little late to join it, with the hybrid
cochlear implant, but the advantages of this strategy are
improvements in speech, noise, and also music appreciation.
If I had to predict, I think in the next ten years, this is a
device we're going to be hearing a lot of.
There are so many patients that have a high frequency hearing
loss that this applies to. When it is approved by the FDA,
there's going to be a large number of people that
potentially might be candidates for this.
So I'll move kind of through these other areas as Ruth
covered most of them. I want to speak just for a few
minutes about regenerative therapies for hearing loss, or
hair cell regeneration. Most people here are probably
familiar with-- In the majority of cases, 80% of
the time when we lose hearing, it's the hair cells of the inner
ear that we lose. This is what they look like.
There's three rows of outer hair cells and one row of inner,
and these are within the cochlea, not hair cells like
otherwise. When a chicken loses hearing,
their hair cells are lost. This is what their inner ear
looks like. But with time they're
regenerated. However, in higher vertebrates,
mammals, when we lose our hearing, this is the normal
cochlea, this is after loosing our hearing from too much
noise for example, there won't be any regeneration.
That's why hearing loss is permanent in humans.
For many decades there's been a push for hair cell regeneration
and progress is being made. There are three approaches that
have been taken. One is the thought that can we
deliver genes that we know are important to the development of
hair cells into the inner ear and make new hair cells, once
they've been lost. We'll call that gene transfer.
Another approach is, there are is population of stem cells that
lives in the inner ear, at least in young mice and other rodents.
Can we harness the stem cells that are already present in an
inner ear in some way to repopulate the inner ear
with hair cells once they've been lost.
And the third approach, can we take stem cells, if you will,
off a shelf, some type of stem cell that we have access to,
that can make any cell in the body, and turn them into hair
cells and transplant them and have them ingraphed into the
inner ear, into the cochlea, and function.
Those are three approaches being taken.
We'll move a little, with time limits here, through this.
The initial approach, the gene transfer approach I was involved
in research with previously. The approach has shown promise
in that we know of some of the most important genes to
regenerate hair cells. In fact there's one gene you
might have even read about, which is called math one, or
ATOH1. Think of it as a master
control gene. When it's turned on, a certain
tissue knows to make a hair cell.
It's a very potent gene in the interest of regenerating
hearing. It's the probably the foremost
player in this approach. We've shown that with delivering
this gene into an inner ear at a very early stage, we can
make extra hair cells. Here's a normal cochlea with
three rows of outers, and here's extra hair cells.
We characterize those hair cells to show that they be
seem to be doing the things that hair cells do.
Most importantly, when we record from them, which shows
actually their true function, they're working like hair cells
when we make new ones in the inner ear.
Also we've shown that they can communicate with the brain.
They can attract nerves rootlets to grow to their bases.
This is a promising advance and there's been more beyond this.
With the gene transfer technique, we know the genes and
there's some evidence that this potentially can be used in
animal models. It's a long way from it's
application to humans, but it's really one of the most promising
approaches that we're continuing to work on, a gene transfer
approach for hearing restoration.
The other approach I'm going to skip to, but one I'm actively
involved with here at the Waisman Center.
As Teresa covered earlier, UW-Madison has had a prominent
role with regard to stem cell research.
The Waisman Center, on the sixth floor, is really kind of the
nucleus of neuro stem cell research.
Not only the research I'm doing with regard to stem cells and
their applications in the inner ear and hair cell regeneration,
but also for other neuro degenerative diseases and also
for vision loss. There's a clustering
of researchers here at the Waisman Center, and we can tour
some of these labs if you would like.
In my lab upstairs we're working with the strategy of can we take
stem cells that can make any cell in the body and give them,
in culture, the signals that they need to make hair cells in
a dish. Then can we potentially transfer
those cells to an animal and restore hearing, get them to
ingraft in an inner ear and restore hearing.
What you're seeing on the right here is, when we take stem cells
that can make any cell in the body, and we culture them the
right way, we can make cells that go on to form neurons like
would be present in the brain, and surrounding them these are
cells expressing an inner ear marker called Pax-2.
What that tells us is that we're somewhere along the way towards
making a hair cell. We haven't made it in culture
all the way into making a hair cell, but I like to think we're
about halfway there in generating hair cells.
We've given these cells important initial signals to
point them in the right direction to where we hope
to ultimate will be. These are some of the questions
we continue to address. Can we make human hair cells in
the lab? Can we transplant them,
and are there inner ear stem cells in the ear already
that we can use to replenish? With regenerative therapies,
when will they come about? This is the question that nobody
knows the answer to. I have no insight on that.
I would like to think it's as close to as five to ten years
away, but I think that's probably optimistic.
We can't base our decisions, as Ruth touched on,
with regard to what we have now. We have to go with what we have
now and what works well. This comes up clinically, and
I think waiting for hair cell regeneration, it's an open ended
question at this point. And then how, I covered some of
the different approaches, and then where hopefully, we'll have
a part in it here at UW-Madison. Here's my summary slide.
Cochlear implants, as we discussed, on multiple talks
this morning, are playing an increasing role.
The candidacy evaluation is comprehensive, the surgical
goals and risks are relatively scripted and well known.
There's not a lot of variability in that on the whole.
There's research into improvements in cochlear
implants that's ongoing here on campus and elsewhere.
And also there's active investigations into regenerative
therapies for hearing loss. I want to acknowledge the
Waisman Center and Marsha Mailick Seltzer, who
couldn't be here with us today. Again, thanks to Teresa, for all
her efforts with organizing things today, and Kerry
McConnell is the coordinator of our cochlear implant program
here at the UW, and I wanted to acknowledge her efforts
in having this come to fruition. Thank you very much.
I'm not sure I have time for questions or not.
[applause]