Thank you, and, good evening and good morning and, and what other good days you guys have out there. Glad to be able to, hopefully, share some of my passion with the ear diseases as we see them in, in clinical practise. Everybody have to deal with it if they want it or not, if they work in clinical settings, I'm sure.

I'm fortunate enough to be in a, in a place where I have surgeons doing what Arthur just talked about and I don't have to do it and I am very, very happy about that. As we all probably have kind of looked at how often we deal with ears, some of the older papers are saying that somewhere between 2 and 6% of, of cats out there will at some point in their career have, a, a need for an ear diagnosis being made on them, and I, I find that probably a little lower than what I recall from my old days in general practise, but that's definitely what the literature is saying, and, and in dogs may be as high as 15 or 16% in some papers. There's a couple of British papers about 10 years old, that was 10 years ago they were looking at it and as much as 30% of the dogs had a diagnosis of ear disease in that paper of about, I wanna say almost 3000 dogs in general practise.

So maybe there is some variation across the country and I'm sure that that is also what you sometimes will experience was a an insurance company in the US that looked at 58,000 insurance claims in 2007 where the numbers were as high as 30% among dogs. So, a common occurrence and therefore, it might be helpful to have a, a good chance to kind of think a little bit about how we attack this when it gets too frustrating and maybe I can share some of my techniques and maybe help you guys out so you don't have to hit your head into the wall the same way that I have done over the years. So here's kind of a brief overview of what I'm gonna try to kind of cover in, in the two halves.

I'll, I'll take a break somewhere in the middle so people have a chance to rest their ears and, and hopefully, not get too tired of me talking about ears all the time. But the clinical examination part is, is an important part as you all know, and then I'll try to go quickly into the things that I find that can be Sometimes overlooked and, and, and lead to some mistakes, so maybe that can help you guys out. Anatomy is more to just use the common vernacular or terminology so that we all when we record and, and write our things down, get things kind of shared among our peers, so we don't have miscommunication unnecessarily.

Pathophysiology is, is, is maybe helpful to kind of review so we can also, communicate with our clients why we're doing the things we're doing and then that, that is definitely a key part of chronic dermatologic problems and so for ear disease, it can definitely be helpful to, to have some good clues or some good ways to review it with the clients. And for that purpose, I will go and use, one of the, the terms and then Craig gryphon and others have modified that over the years in different ways with the three pieces of ear disease, plus some modification from an older classification system with primary and secretary can sometimes be kind of superimposed and that's probably what I find myself doing most of the time. Then the diagnostic treatment consideration is what we do every day in clinical practise and, and I'll kinda go through some of the steps that I make sure that I teach my younger peers when I have interns and residents come with me, with the cytology being key and the cultural and susceptibility that we all need to, to have and do and, and some other Pitfalls of, of culture and susceptibility, is, is important to stress, and then it might be varied from region to region, but it will be interesting to see if anybody has specific, points to make or share.

And then I will use that to base my treatments and maybe go through some of the, the, the international drugs at least some of the things that I think most of us would find comfort in using. So, diagnostics is obviously always the fun part with with ear disease and I just want to stress this part of my everyday viewpoint. I can't say this enough to, to my clients and to my colleagues, but to me, ear disease is a skin disease and I will even venture, a slight modification on this slide and say, a chronic ear patient is probably an allergic patient until proven otherwise, at least if it's a patient younger than 5 when they start their career.

Others might disagree with that, but that is definitely what I see again and again. The full history is key, and I know a lot of my referring vets and my receptionists around the country or there's in the region where I have cases coming from are sick and tired of getting requests of getting the full history. I often will get hundreds and hundreds of pages to review and sometimes it seems a little tedious, but it is often very helpful to have where failures or where successes have been accomplished with treatment of ear disease and it can help us kind of Figure out if there are patterns of disease history that helps us out.

The prior dermatologic conditions, non-ear related is key as well, and that is also part of the review and that is helpful in my view, definitely to, to get to the some of the path physiology figured out. The full exam, and I'll often find myself, spending the first couple of minutes on the floor with a dog or cuddling a cat in my arms, looking them over before I even greet the clients, and the clients sometimes a little kind of taken aback, but I wanna get my, my hands on those, ears and feel for changes and patterns and lumps and bumps and pain and and cartilage changes that can be helpful. And I, I spend those minutes because it gives me a chance to kind of look for the subtle clues that can help us out.

Is there pain from the term manipul and joint? Is there symmetric, muscle mass or asymmetry? Is there other subtle things that I can see?

And I often find that if I'm not quite sure. I even sometimes go on and talk to our neurologist and say, I'm looking for a subtle clue here, but is there a decrease here or are we seeing some differences here? And, and it helps me out sometimes for having just a second opinion on those because it can be those subtle things that then determines that we're gonna go for more expensive or more elaborate procedures.

So, there's nothing wrong in my view of asking for second opinions even among what we're supposed to call ourselves specialists. But look for those subtle clues and it helps you out, record them and keep track of them. Diagnostics is obviously involving all kinds of tools and, and I'm sorry, I keep repeating myself here with the term pace, but I have to do it.

It's in my contract. I can't take that out. The otoscopic exam, the 1st 500 times you do an otoscopic exam, you're probably gonna be pretty bad at it.

And then somehow after the 500, you start getting a little better every day, maybe. And it's just a matter of keep practising, get good at it and Don't be shy about admitting to the fact that if you don't see what you set out to see. It is not always possible to see the full metic canal.

It's not always possible to see the tympanum, and it becomes part of your workup is to say at the initial exam, I did not see the tympanic membrane due to a B and C reason. And when I treated it with A, B, and C drug, I was able to or unable to see that part of the ear canal that I had hoped I was able to. These things should be kept track of and it helps you hopefully in the process of, of managing these cases.

Cytology is gonna be a helpful tool for most clinicians, I would hope, and then the better you get at it, the better you can help your patients. So, get comfortable looking at slides and get those calluses around your eyes because it is a key part of our work. Direct microscopy is probably fallen a little out of favour, particularly with the advance of nice antiparasitic drugs, but they're looking for, ear mites is not all we need to look for.

We need to look for also sometimes demona, even though it's not that common, it can be pretty detrimental as I will show you later in a slide, from a histopath. So just cheap stuff, it takes 2 seconds to take that ear gunk out and just mix it up with some mineral oil and look at it to make sure that there's no surprises. And it just becomes part of the routine if you do it all the time, it's, it's no biggie, but it helps.

And then the culture susceptibilities and those are key with today's antibiotic resistency being growing in, in almost all fields of veterinary medicine. So getting comfortable and having a good lab in your corner is gonna help you out, I would hope, and getting an understanding on what the lab is trying to give you and how you can use it is gonna be part of your, hopefully everyday routine as well. So find a good lab, communicate with them and ask them.

On his questions and say, hey, why are you saying this to me? What is your definition of contamination and those kind of things? Here's a little side gear because as a dermatologist, we don't have a lot of fancy equipment like the surgeons or the neurologists.

But here's my good old trusted first video scope. I call him Otto von Schortz, and he is, semi-retired now. I still use him occasionally because, I'm a sentimental soul, but I've used in, in, in a lot of cases, and I actually use my video scopes in the exam room with the clients.

On a regular basis because it has proven to me, at least, to enhance owner compliance tremendously for them to see what's going on in their pets ear canal when they're been managing it for a while. It helps them sometimes. Kind of understanding why this is so important.

So bringing it up on a screen and showing them what's going on in the ear canal or seeing it at the recheck and then have them understand that, hey, this is why I wanted you to treat for the full 14 days, not just the 1st 5. And you can sometimes clean a little bit while seeing, and at least with the video scope, you have the, the possibility of seeing underwater where with a handheld while Allen or other forms of otoscopes without a, a light source within a scope head. .

The, the, the fluid within the ear canal would make it very, very hard to see details underwater, whereas the videoscope allows you to, to, in some cases, at least to see within that fluid that is suspended in the ear canal, and that can be helpful, . Obviously, a little easier if the, the pet is fully anaesthetized, but even in, in some cases with the friendlier patients, you can sometimes fill the air with warm saline and, and get a decent look. Not always a clean look, but you can get something seen.

And that is sometimes helpful with the videoscope. And here's my newer acquisition, so this is Richard, as I like to call him, made by Richard, Richard Wolf, it's related to, I believe the Stryker family. So, it's just a newer camera and a, a nicer flat screen, and, and it still has some pretty nice, over here has a capturing device building that's more like the standard phone snap, iPhone type of thing where you can put a little flash drive in and, and record videos and so forth.

Documented the changes is probably more for my edification afterwards when I've done procedures or to, to go and kind of say, OK, why did this not work for this particular patient? I can go back maybe and see other things down the road. I don't think there is room enough in most practises to kind of do this for each patient and, and take pictures, but I'm sure some people are able to do that.

Minimal invasive procedures and I was just asking, the previous speaker a little bit about that, and that is some of the things that I'm working on right now through my videoscope, with various things of debulking various forms of tissue in the ear canal, and I have also been able to do fine needle aspirates through my working scope here where you have a little working port. You can get various tools in there and get pretty delicate biopsies, collected with, with less invasive, than, than full surgery. And specific sampling from the middle ear can be accomplished in a sterile manner, through the scope or from specific areas where of interest.

So that can help. Mengotomy can be a little easier to do because you can actually see and collect through the scope and, and do these things very accurately with. Not having to worry about the, the, the speculum being contaminated, or the, the tool that you're trying to insert into the area being contaminated because within the working port, the, the tools that you're working with will be protected and, and kind of shielded from contamination from the surrounding ear canal.

CO2 lasers have been tried, and I have, various tools for that, but it is unfortunately, fairly limited with the angles of the working port to, to get a good working laser working long term and you can get a couple of, of good quick shots in, but you can't keep working without often finding the laser tips being damaged in the process. And lately, I've been working with bipolar cauterising tools and trying to modify from human to, to be able to work through that. But I'm not gonna bother you too much with that.

This is just my little pet peeve of tool kits that I love to have and as one who works for the years every day, it's sometimes helps to have these to, to, to help my peers in the general practise out there to do things that they don't necessarily want to pursue themselves. So, the diagnostics of other things, imaging, I would say CT is very commonly used by, by Derm here where I work, an MRI is often in the, the joint sphere between neurology and dermatology where I find myself, often. Working with my pews in, in the 3 neurologists we have here and, and they prefer the neuro the MRI for, for for brain changes and I can work with them when they have middle ear disease that they want me to address or drain or a sample.

The CT gives me a little bit more wriggle room for some of the changes surrounding the, the, the soft tissue on the outside. So it's, it's a compromise. I would say those are nice to have and not all practises have both, so obviously a little spoiled.

An X-ray at this point is probably of very little value in most cases of complicated ear disease. It can Not tell you as much as, as you probably need at this point. To measure the, the pressure in the middle ear is more for humans, I find that I can sometimes use a modified one where I flush through my videoscope to see if the eardrum is intact.

So it's not quite a measuring of it, but more to see by pulsing saline through my videoscope, I can see if there's partial tears or modifications to the eardrum that I have to, to kind of assess and, and it allows me to, to say with a high degree of certainty if the, the, the eardrum is intact. Bear testing is something we're working on and, and we are looking into a new little portable kit that, that seemed to be, possible for us to maybe get some additional stuff, maybe document things before and after certain procedures, but this is still early times for that. And then obviously, diagnostics of biopsies, fine needles, and histopathology samples from what you have removed either through surgery or biopsy.

And here's just, everybody can probably see what's wrong with this X-ray, but that is not always the case on, on X-ray. So I would say in most cases where X-ray can see something, you probably can already guess what you're gonna be looking at. And then with the CT you have additional options with contrast and manipulation of the images and flipping them around and doing other things too that can be helpful.

And therefore, it's preferential and obviously with the MRI similar. The total pen is, I, I've never really gotten good with this one and I, I don't think I'm gonna be using it much longer. So, that's it.

But there's the new bear tests that we're looking at. It has some potential use and I'm, I'm kind of probably just scratching the surface on that one. So, starting with anatomy, just a quick review so we can kind of use that down the road, but telling the owner that, hey, this ear canal is very different from yours and a dog, the ear canal is often 34 times longer than a human ear canal.

It takes them a little while to comprehend that this is why it's so difficult to treat time at times and showing them and, and reminding them helps them to understand why they need to treat the whole year and not just a little part they can see on the surface. So, Overall, the ear canal is this fantastic piece of skin, and we work on it and we hopefully get better at managing it, and just using these terms, I write them in my records so my peers know where I took the sample from or what I saw or remind myself the following week why I wanted them to see back for that change in that particular section can help me out remembering what I probably would have forgotten. And just to kind of remind that we sometimes need to think of volume and retreat, and this is just a a little bit of when we come back to treatment is that in a dog's ear, the volume of an ear canal of a 10 kilogramme dog is, is at least half a cc.

And when we look at most of our commercial inserts of ear treatments, you'll often find that they're recommending that you're treating with 2 to 4 drops once or twice a day, in a dog of more than 10 kilogrammes, it is likely gonna be heavily under medicating that particular ear canal, and I'll give you my suggestions later in the talk. And this is just to point out that the ear canal is quite extensive into the depth. And when doing an ear exam, sometimes it helps to remember that you're inside the skull and trying to jam the scope to make it fit or to see will often make the patient object heavily and And I try to show my, my colleagues that they shouldn't feel the pain from being examined.

If, if that's the case, it is because we're willing to scope and we probably should be letting the ear work around the scope rather than the scope work within the ear. But pain and training, will often teach us the hard way and if the patient bites us, it's typically our fault in that respect. So just putting it in, in the Inside the head, and these are just the parts that we often are trying to get at if we have chronic ear disease, we want to get into the Ebola of the dog.

And just as a contrast to the next slide where you will see the, the cat, ear canal being a little different, it's outer ear, and it's often much shorter and much more direct, whereas the dog often will have that large kink in the middle. It's a little shorter and a little bit more flexible and I, I, I suspect that that's probably also why, Arthur was saying he, he found that ear tea was probably a little easier to do is That they're often not as minimised or the cartilage is not as damaged by chronic inflammation as we sometimes find in the dogs. The tympanic membrane is a little smaller and, to your canal has this length in the cat in most cases.

The part that makes it harder for us to treat middle ear disease in cats is, is often they have this separation in the middle of the the bulla, and it can be complete or partial, that, that can make it harder for us to reach all aspects of that cavity if we have disease trapped in there. And obviously, we want to be careful, also not to do too much damage with the nerve. Distribution that the previous speaker showed in his, my slides of surgery.

So, the eardrum is what we are looking to find when we look down in the ear canals. I feel at times we're seeking for it. Here's a nice picture of a cat ear, and the cat eardrum is often this very nice clear view when we're looking at it in an otoscope because the eardrum in the cat is much more upright than the typical slightly slanted canine eardrum.

And so with a single view field of a handheld or video scope, the focal point of the single view will often make the top part of the eardrum be in, in focus on the lower part, not so much if the eardrum is, is slanted as it is in the dog, whereas in the cat, you will often find yourself, you can get the whole surface in the same plane, if you will, and therefore, you get this nice clear view and then you can see the the backside of the boa where you can see, part of the, the, the medial aspect of the bola there with the white shade coming through with the eardrum is healthy and intact. See if we can get the next one here, stuck. And obviously, where it's located, the eardrum is this four layer thick, membrane that migrates around the ossicles in this case with the, the, the malaise sitting there with a little membrium pointing to, so in this case, the right ear pointing towards the nose, .

There's some of that species variation that we just talked about. Here's a key on your drum where we'll have the upper part being a little bit more bulging and, if, if you poke a hole in this, which I encourage you not to, this will deflate very quickly, but it's basically just this slant, slightly slanted eardrum. This is not a tumour of the ear canal.

This is just some of the normal variation you'll find in, in certain patients ear, even left to right can differ. This paper was actually kind of interesting for me to dig up when I did this preparation here for, for these slides is, Doctor Cole and her team out at the Ohio State, back from 1998 reported that as many of chronic, as 50% of the chronic cases with canine chronic otitis externma had a ruptured tympanum. And I guess I'm, I'm when I think of it, I was like, wow, that's a lot.

But then when I start looking at the cases that I see when I have them under for deep ear flush or maryotomies and other things, I often find the eardrum already being perforated in, in, in one. Multiple places. And, and so I guess we just need some newer data on is that truly representing what we see in general practise or referral practise or other newer, newer numbers out there to, to report.

And here we can see the lower part of the drum where we have these little hair. Indicating that if you see these hairs as you're coming in with your scope, this is your little flag that you're getting pretty close to the eardrum, and if you get much closer, you might end up doing this little perforation up here where this fluid is, leaking out from the ruptured eardrum. The pars flaccida is the term that textbooks will tell you on, and this is the one you don't wanna poke into.

This is where we're gonna have a lot of stem cells and blood vessels that we don't wanna mess too much with if we want the eardrum to come back and heal. . This can be a little bit more flesh coloured as we just saw in one picture, and I'll show you some more of those.

Here we have a, a classic dog again looking to the right with the pars plasa being up here and, and a little bit more flesh, and you can see these beautiful criss-crossing vessels and, and they'll often have that fleshy appearance, whereas the, the lower partenza is much more transparent and you can see the bullet through it. . All right.

And here we have the Partenza, and this would be a good suggestion of a place where you could do, your meningotomy if you are looking to do that. Obviously, not on a healthy year, but on a year with some sort of disease that you're interesting to examine or resolve through your mengotomy port. Here's another picture of a canine here to looking to the left, ear drum and we have a little bit more fleshy.

There's actually probably from a cat if I'm not much. Mistaken, but in all fairness, just examples of the same thing where we'd be looking to do our economy down here about what we consider 6 o'clock position or somewhere between 4 and 8 is probably a good safe place without reaching the stem cells and the vessels. Other examples.

He's a I don't think it's been recently reproduced, but most of the textbooks will probably say that somewhere between 1, after doing a marotomy and an eardrum, if it's unhealthy ear, that it will heal pretty quickly and, and, and, and appear intact within 3 weeks. But in cases with more chronic debilitating disease, it can take up to 4 months for That eardrum to heal, and that's definitely seen of cases. But it does require that the ear canal on the outside of the eardrum and the bulla on the backside is healthy, so you're not getting interference with the wound healing process in and around these tympanic membranes.

The epithelial migration, and this is a kind of a a pretty cool I think we have, sorry, I thought I have the reference. I must have cut that out. I apologise, but there is a really nice paper out from the Ohio State where they looked at the migration.

And what they did was they put these little ink droplets on various parts of the tympanic membrane, the parts tensor parts plaida, and then documented how these ink drops moved away. As the migration of the lining of the The canal is moving outwards and away from the centre of the eardrum. So, opposite most other pieces of skin, the ear canal lining actually has a directional growth almost To help with the self-cleaning process and that is a pretty nifty little thing.

And unfortunately, some of the things that we often find getting damaged in chronic ear disease and hence it is failing for the self-cleaning part of the ear. So That was anatomy quickly moving through the next couple of places where we're gonna find most of our meaty parts. So apologise if anybody has drifted off so far, but I try to keep it as quick as I can.

The pathology of ear disease can often be kind of complicated if we don't try to break it down into comprehensive bites and I'll try to do that quickly. So the predisposing factors are obviously things that will increase the risk of creating inflammation or ear infection in, In the ear in some form of a way, but it wouldn't do it on its own beneath that additional kick. And so the predisposing would make it likely to occur but not create the problem.

Perpetuating would be things that would worsen and maintain problems and would even to some extent prevent from the, the resolution or elimination of the disease or problem symptom. And then you have the primary factors where you have that can Conditions that will initiate inflammation in the ear canal one way or another, and then secondary factors would be the ones that do perpetuated that part. Here's an old slide from back when I was in that school and then they say illustrate why so much of our review probably were a little bit missing the point on particularly the allergies because we kind of just went through the whole thing and then we got down and then we ended up with this.

And then I think this is maybe a little bit more hopefully helpful to think of ear disease as a combination of These different groups in one form or another on an individual patient, leading to the tits external, and for some cases, it starts with the primary cause being the majority and the perpetuating being 10% and so forth. But this is maybe the way that we should kind of conceptualise why ear disease is not a simple solution for all things. So, the question before about Sharpes, and I would say in my case load, we do have a good amount of these American bred Sharpeys with severely malformed anatomical features associated with ears that almost make it a guarantee that they're almost born with a chronic ear disease or very close thereafter with their synotic ear canals being inherited from the positioning and the placement of the cartilage in conjunction with the skull.

Bulldogs have a, we see so many bulldogs around here in Boston, and it is obviously the Boston Terriers and all the Frenchies and all the English bulldogs and Anything in between, and those are your canals will often further be not necessarily as bad as sharp pace, but often be very, very narrow at the last section of the some of the canal, which will make it harder to visualise, but also harder to maintain and treat, part of your canal. So bulldogs might have an anatomical predisposing factor in there too. The pent up the hanging ears, I would say they're not predisposing, but they're often maybe more factor where the owner is not noticing the ear symptom until it's too far into the process as it's hanging under the curtain, they don't pay attention and not seeing the symptom until it's really far along.

But that goes obviously for spaniels, bloodhounds, basset hounds, and others. The excessive hair growth is typically not much of a predisposing factor in my view. They can make it harder to medicate and they can be causing ear disease if somebody is trying to, pluck or remove it, but in most cases, ear disease from here is typically rare.

But there are definitely breeds that have pretty hairy ears and, and as such, pay attention to those and make sure that there's nothing there that we can't see. Obviously, we can miss things because we can't see it. And if I do remove hair in the ear, I will often medicate the ear, whereas a groomer is probably more likely just to remove the hair and create a problem for you to deal with down the road.

Ear wax is What owners don't like, but it is an important mixture to help us keep the ear canal healthy and, and with the lipids and the antimicrobial proteins in there, the IgGs and IGAs and IGMs helping with the bacteria and the organisms and other things with the lysosys that is found in the, the mixtures of lipids and fatty acids and other things, plus the pH creating an environment that's favourable for stability of, of hopefully more healthy organisms. So with that being an abnorm a normal situation, the, the imbalances in this will lead to complications of ears and create a predisposing factor, you know, good number of conditions. For example, if there's been trauma from infection or surgery or plucking or other things, the, the epithelial migration is no longer providing the conveyor belt or cleaning that we need.

If we have specific keratinations, defects in the ears due to trauma or scarring or conditions where the lining is altered. And then we have the superic diseases ranging from space thatitis, primary super vitamin A responsive, and other that impact the quantification process also in the canal. This will lead to excessive scaling and accumulation of debris in an unhealthy balance and then you have infectious prone environment in that year.

Secondary with endocrine and hormonal conditions where the quantification process is altered due to, for example, hypothyroidism or Cushing's or other hormonal imbalances which render that ear canal also more in favour for infections. Hydrogenic is where we have gone in and done stuff to it. The swimmer's ear condition, as we see in humans swimming in a chlorinated pool or a, a, a body of water with some sort of organism in it, is, is possible and I, I guess it occurs but are typically not referred to me.

But I could imagine in general practises might be a problem. But what owners often come and say is swimmer because the dog has been swimming, and only have ear infections, part of the ear could also be misconceived and, and should obviously sometimes lead to an exam for other clinical findings because the ear might just be the top of the iceberg and the dog is really in the summer at top of the dog that only swims in the summer and chews its feet and other things concurrently. Bathing, I would say the clean water should not cause problems, but I guess it is possible that you could have an irritant from a bath, but it would be very, very unusual.

Relative humidity is probably a little bit misrepresented in some textbooks in my view, because I think where we have relative humidity, 50% or higher, we also have a pretty interesting, environmental pressure and some of these animals probably have environmental allergies to those particular . In that high humidity and, and, and maybe that's why they have ear disease as I will try to cover in, in my, one of my slides a little bit later. Trauma of various kinds by Q-tips, erosions formed by that or by plucking by groomers or owners or even veterinarians trying to look, and then obviously an otoscopic exam can also create a traumatic event in the ear that would facilitate and predispose for.

Ear disease, and I don't know if you guys see it, but I see, a broad range of home remedies downloaded from the dear Doctor Google, and some of those things are pretty scary when you think of what this might do to an ear canal, in certain situations. So, we do see those as traumatic events at times. And I'll show you some pictures of that too.

Treatment, and this is more in quotation mark than anything else, but the owners who have been told by their vet to clean the ears once a week or every 14 days, and they did it, but why not do it twice as much or 3 times as much, so instead of doing it every 10 or 14 days, doing it every 2 or 3 days, sometimes these years will come in and be completely macerated and under the proper circumstances could probably facilitate or maintain ear infections or irritation in such a degree that the problem become chronic. On the medication is probably where we're finding most of our perpetuating factors. The owner is treating not long enough or they forgot to treat as I, I tell everybody who wants to hear is owners don't lie to you, they just don't remember what they forgot.

And that is true. They say, well, I did treat as you told me to because they can remember the 3 days or 5 days they treat it out of the 14 days, they forgot about the other days. They might be reminded about it, but they typically will answer honestly and say, no, I didn't treat.

They just forgot about how many times. The wrong drug can happen, but most of our cases are really well managed when most veterinarians are doing their job the right way. And so, it's typically more the wrong drug because the infection has shifted during treatment, not as much as we pick.

An antifungal for bacterial infection or the other way around. Under dosing, and we'll talk more about that, but that is typically one of the main reasons why we're getting in trouble because we're not getting enough medication into the area we need to treat either because we put too low a volume in or because it's not accessible due to scarring, obstruction, or the patient being unwilling to medicate or tolerate medication. Owner compliance, is a, a major factor in why we fail at sometimes treating an ear successfully and, and so as a treatment failure, is considered a treatment, I guess.

And here we can see a patient that where the owner had decided to try to go on the internet and had not been able to find all the remedies, so he improvised and used, what he thought was a glueing agent, supplement, and it turned out to be a very, very horrible ear canal afterwards, almost to the point of animal cruelty. Here's where our job really is. If we fail to eliminate the underlying primary or disease-causing process that we've been trying to treat.

If we don't get it that better, that's where perpetuating factors will often become almost never ending. OK, obstruction of the ear canal due to a tumour of various kinds. The polyps that we were just talking about in the previous lecture, I would say we see it a lot in cats, under 2 years of age, but we also see it in older cats.

And then we see it on and the bulldog breeds, Frenchy's a little bit more, pugs, Boston terris and and English bulldogs, and there it can happen to be both in the bola and the outer ear, and they can be pretty horrendous and cause all kinds of problems. . And here's a nice little picture of a feline nasopharyngeal polyp, and as the torsion and twisting and pulling them is very gratifying, but it obviously can be a lengthy process if there's more than one.

Adenomas in the ear canal, outer ear canal, various, other glandular tumours, the plasma cell tumour, is not uncommon in my experience. We see it in older dogs a little bit more, and then we occasionally run into a papillometers, mass in the near canal after exposure to the virus in, playgroups and otherwise. And then we have the hypoplastic masses in the air canal where we have cystic changes and also mentioning here the prolife neti disease.

. And here's an up close of a systematosis, and here's a feline necrotizing ear canal, so you can see how that could obviously work as an obstructive disease. Malignant neoplasias are definitely, obstructive and as many as 85% of the ear tumours in cats will often end up being malignant, and, and maybe only as much as 60%. In, in dogs.

I think some of these data need to be updated. Most of these are on older date, even though this is from a review paper, the original paper was from Goldsmith and his group and, and it's probably being in the late 90s. So we, we need some new papers looking into these prevalences and the true data, maybe not just in, in, in the east coast of the US but across the globe more broadly.

Interestingly enough, they're pretty rarely metastatic to the, to the lungs, only about 3 out of the 35 dogs listed in one paper, and none of the cats, had metastatic activity to the pulmonary tissue, but almost 10% had regional involvement in the cats, with the lymph nodes being involved in the cancerous disease. We see a good amount of adenocarcinomas with mixed, seruminous origin or a glands being in there. We see squamous cell carcinomas with various degrees of calcification and then basal cell or mixed tumours like this one.

And here we have a cat with a squamous cell carcinoma that is, can't see in the picture. But tell him, trust me, I tell you it felt like a golf ball attached to that side of the head. It was minimised through and through, so putting a needle into it, you could feel the crunching.

Do a little quick detour and I'll make it very quick because you can see I'm running a little low on time, but I'll try to kind of quickly go into a little pet peeve with the, the cats because they're underrepresented in a lot of our stuff. So here's a necrotizing external in kittens. It's supposed to call them in literature, I would probably say in cats because we see it, also in older cats now, and they are often bilateral and very, very acute and very, very painful.

There's no obvious breed or predisposition. I've seen it in purebred or mixed cats. And the ear canal after dealing with will look.

Very, very damaged. . But surprisingly quick if able to rectify this secondary infection, the ear canal will often go back to a more normal level.

And looking at this, you think this angry, angry ear canal must be some sort of cancer. But there is some evidence in there that this is maybe a T cell overreaction and these little hard to see little pink cells in here are pignotic cells that are almost The apoptotic keratinocytes are being shut down by the T cells and then it, it appears to be a bacterial-driven disease that comes up with this almost horrendous autoimmune-looking disease on histopath. But if we get on top of these infections, they actually do fairly well.

And if we then go after the T cells with something like cyclosporin or tacrolimus, we can get them to respond fairly well. So here we get rid of the infection, they actually tend to Prove and there's no viruses or parasites found, and the apoptosis is driven by these T cells, so we use cyclosporin or drugs in that class, we can get some pretty nice response in some of them, not all but some. Systomatosis, this is a confusing disease for a lot of people because the names are extensively Over the years been piling on, and there's more than 20 different names last time I counted.

So all of these are probably fair game, but I prefer to call it systematosis. It is in the textbooks listed as a 4 to 8 year old disease occurrence, or that's where the majority of them are, with probably, an overrepresentation among male and neutered cats with the Persian cat and Himalayan cats being affected more, prevalently. Here's where the disease starts.

Apocrine glands are found at high density in the upper ear and spaceous glands are lower in the ear canal and that kind of gradually decrease upwards and the agri glands decrease downwards. In the cat, they have these. Glands in the surface area of the epithelial lining and what is happening here is that these become cystic.

It is, Basically a reaction or hypoplastic. Reaction most likely in the cystic areas of the glands and of these glands becoming cystic, leading to this kind of spectacular histopath where you can see these dilated glands with this crystalline material entrapped in there. The material looks like it should be black or blue, but it is often more cream coloured when you pop them.

So it's a little misnomer that some people call them blueberry disease. They're Not blue inside, but pretty cool and can be very painful when they get secondary infected, which they often will. Here's what I see.

In my last 7-8 years, I found about 52 of these cats with a total of 50, 88 years and I'm in the process of writing this paper up, so they hopefully will be published soon. But we found that the Prevalence in our population is closer to 10 to 11 years of age with a span of 3 to 16 years occurrence, and this meaning the first time it's diagnosed. There's no race predisposition, so the Himalayan and Persian cat is a at best, it's probably not true anymore.

Slight overpresentation, I don't have the odds ratio for you, but it is definitely a little bit more prevalent in the male cats. They're all basically healthy cats. There was no evidence of disease.

Prevalence among these 52 cats that were standing out as one being Or groups of diseases being found. Majority of them were FELV and FIV negative. I had two F one FIV and one FELV positive, but both have had this disease for years, almost 5 or 8 years for these two cases before they started getting your disease.

We did a little study where we looked at the papilloma as a pro-oncogenic entity, and we found in 23 of the 24 cats, we were able to test on tissue to be negative for 8 to 12 different papilloma DNA sequences and later on additional and only one cat was positive for feline papilloma 2 virus, which is not associate. With an oncogenic entity. No, no other prior ear disease was known in the records when we looked or when we talked to the owners.

Interestingly enough, 5 of the cats we looked at had neoplastic and malignancies, but when we think about it, it actually probably more reflection that these cats are 10 and 11 year old and might have a predisposition for cancer, not because of their ear disease, but because of the age. And here you can see that you can have these acorn glands away from the ear canal here on the side of the face. You can have them around the eyes as well, and you're gonna have them around the rectum and even a couple on the lip margins.

So Back to where we came from. Allergies is number one reason why people come and see us, right? That's where allergies and ears are connected.

And if we don't remember that, we probably should. Food allergy Often will have ear disease, bilateral. Not uncommon that they have worse in one ear than the other, but they often will have bilateral disease, but sure, you can have exceptions.

They will often get worse over time. So they might start with bad ear disease at age 2 and be really bad by age 5. In my part of the world with four seasons, we consider food allergy should never have a seasonal variation.

If it does, there's something else going on. Feline insulin is low. There's not a good number of papers, but the most recent from the gut is in feline internal medicine is probably listing it as low as 5 to 7%.

Percent of cats with confirmed food allergy occurring with ear disease as part of their presentation. Where in dogs, it's probably as high as 80+% of dogs with food allergies will have recurring ear disease as part of it. Concurrent or alone with other non-seasonal dermatologic symptoms, poly and and other things, but it could also be GI symptoms, obviously, if you have food allergies, some of our patients will have skin patients, skin symptoms and others will have gastrointestinal, and there's a, a pretty good chunk of them they'll have.

One older paper is stating, citing, up to 24% of their, patients had only ear disease when they were suffering from food allergies. I would say that's probably a little bit more than what I see, maybe closer to 10% in my experience, but the paper is out there and Dr. Rosser does have the right to, to state his facts because he's done his due diligence for your disease and for food allergy in his career.

Adipe, I would say it's often bilateral and it can be quite extensive as we see here with proliferative changes in the tragus. Multiple reoccurring ear infections again is obviously needed to kind of make it an allergic dog. It wouldn't be the first time, but anything more than 2, I would start looking.

50 to 80%, I've probably even venture sometimes up to 85% or 90% of my canineatopic patients will have ear disease as part of their presentation. Here's cocker spaniel with obviously a lot of problems. Here's a nice Horner's presentation and a drooping ear with.

What I jokingly call the flying non position of the ear cartilage being altered. In cats, I would probably venture that we don't have a true incidence study done on that, but majority of clinicians probably saying that. Topic dermatitis in cats do cause ear disease, but maybe not as many.

As 50 to 80 dogs, so maybe closer to the 50% mark is what we would expect. They often have other symptoms like this classic symmetrical alopecia, For both cats and dogs, but if they have it as a single clinical sign, you don't know it for cats alone, but for dogs, around 10% is listed in the textbooks, and I would definitely agree with that, where, of the allergic dogs, atopic dogs, 10% of them have no other clinical manfestation of allergic skin disease but ears. Here's a cap with some penne lesions, just to make sure.

Here's just a key part that I often find a lot of my clinicians will forget that when they look in the ear, obviously see that looks like this you suspect something wrong, but if they then take a swab and look at it and see no organisms, no bacteria, no yeast, they'll say, well, there wasn't any infection, so I didn't treat it well. Allergic otitis externna is a disease and If you don't treat that, inflammation and irritation, it will at some point become infected. So, if you see inflammation in the ear, either microscopically or cytologically with inflammatory cells and other markers of inflammation, you probably should treat that inflammation.

Otherwise, it will progress and you start getting the nodule hyperplasia and edoema and erythema and ear pain and eventually, you will start getting secondary infection. Here you can see further in the edoema. This is the trauma probably done by the otoscope, at one point in the exam.

But all in all, inflammation leads to infection at some point. And if you don't address the inflammation early on, it will become a problem you have to deal with. We don't see too many foreign bodies, but we do have to think about it because it does occur, depending on where we're at.

Plant material foxtails like in California and other plant material can happen, dirt, material of other things, ear wax clumps that has been pushed down will often work almost like a rock and definitely be a problem. And then acquired issues down below. It's probably rare enough that we can disregard that, but medicine is definitely sometimes found in ears.

Because it's been packed in there with these new, packing materials or precipitated due to, inappropriate expired medications or medications that have been too cold or hot, or otherwise shouldn't have been used in that ear. I found a couple of small little, I found a barbie shoe in one ear, part of a Q-tip in another. So sometimes foreign bodies get in there one way or another and when you take them out, you feel quite gratified.

But if you don't take care of it, it will cause China's external, and if you're really unfortunate, it will lead to Chinese media and worse. You see from parasites. I don't get to see them, but they're so much fun.

Here's some of the treatment suggestions when you get those young kittens with a little coffee ground in the ears and you see the little buggers floating around and It is so nice because you know that when you see this, and if you can pull it up. You can pull it up on a Video screen, you can really shock the owner and it feels so nice. But it is obviously, not that often we get to see those anymore.

Drug hypersensitivity, you see it, and I tell the owner that if you put something in the ear and the dog or the cat is reacting to it, stop and let me know so we can figure out if it was due to the drug or something else, but it's probably not as common as we, we sometimes fear, but it does occur. And it can be localised due to a topical treatment or it could be systemically due to a asyncratic reaction to a systemic drug. And I will quickly get through the break, so I promise you you will have a chance to go to the bathroom here.

Drug reaction can look like anything you want, so it can happen in the ear canal. If it was due to an alkaline or acidic topical cleaner or medication, you can have reactions to that, your cleaners, people mixing stuff together that shouldn't be mixed and create problems. Those will be causing, inflammation in that ear.

If it is, localised unless both ears were treated, obviously, it was systemic disease or drug reaction, you can often have a bilateral, but we often find that these are kind of a little bit more unilateral. OK. So we're gonna quickly jump to The last couple of slides here which I don't see too many ticks in the ears, but they are out there and once in a while, we find them and hopefully we can get them out in one piece if they're not too embedded.

DMX is probably a little overlooked in some of our patients and it is important for us to remember it because here's the ear canal where I've been treating this dog's ear with top. On steroids for some pretty long duration, and this dog basically had phylosis in the ear canal due to these chronic diseases with the parasite, probably making it a lot worse. Paella, not too often, but they can definitely be very, very itchy around the ears and sometimes they will make their way into the ear canal by accident or otherwise.

And then the immune diseases around the pena and into the ear like pemphigus, where we have crusting and visicular crusting diseases that leads to exfoliated and pus-like material falling into the ear, changing the ear canal and making it swollen around it. Puppy strangles definitely involving the ear canal, or area around the ear canal leading to disease is not uncommon and often will have to be treated as well as part of it. Erythema multiforme is pretty rare, but I've had one where we had local erythema multiforme like changes on, an ear canal after we've been treating with a topical remedy.

So cleaning the ear, plugging, all those things, as I said, those are key to eliminate will lead to disease, right? So, should we take a quick break? I don't know if my chair is agreeing to that.

If you are looking for something to do in the upcoming year, this would be a good place to visit. Yes, it would be a very good place to visit. We could go and see Arthur, couldn't we?

Yeah, I would definitely make a point of trying to seek him out, that's for sure. So great, yeah, it's, it's just coming up to 10 past. So how, how long do you need for the second half, about a little, maybe a little less than the same.

About 50 minutes. So if we have, if we have sort of, let's say 7 or 8 minutes, then we, we should be able to finish just after, just shortly after 3 because we've got to then get ready for the next session. So that should work, so that's great.

Let's . Reconvene, we'll show the slides off with the sponsors on. Thanks for everybody who has sponsored.