Hi, my name is Charles Koontz. I'm a surgeon in Melbourne, Australia. I've been asked today to speak about innovations in veterinary medicine, specifically relating to surgery and cancer care and neurosurgery and a few other things.

I think that, the advent of, really advanced technology is very exciting and we are privileged to be, practising veterinary medicine in a very exciting time, and I thought I would try to review maybe some of those advancements that we are enjoying at this time. So, the first area that I'm gonna talk about is cardiac surgery, and this looks extremely complex. So this is the setup for a human cardiac surgery with the cannulas that are going into the vena cavas, and you'll have a cannula going into the aorta, down here, the clamp going across the, the aortic root.

And it's interesting that actually, this looks like just a big mess, but once you understand exactly what's happening, Here and what you did each of these things is doing, it's actually fairly straightforward and I'm not gonna say that at the end of this presentation, you'll be able to understand exactly what's going on in this photo, but, suffice it to say that every single one of these things has an important purpose. So early cardiac surgery, I've always been interested in. My dad was a cardiac surgeon, when I was growing up.

And in, and it's interesting that open heart surgery has actually only been around for not even 70 years, about 68 years. And given how simple cardiac surgery was in the early days and how complex it is, Now, the, the, progression has just been extremely, extremely rapid, over the past 68 years. So this first slide shows, early cardiac surgeons and they were trying to repair an atrial septal defect in the heart of a human.

And what they did was they put a funnel into the heart, through a hole in the atrium. And then as long as they kept the central venous pressure below the level of the funnel, they could work at will inside, this heart. And so that's, I always found, I always found that very interesting that the early, cardiac surgeons and, and, early surgeons of any kind were extremely innovative.

In times of basically desperation and trying to repair things, that, up until that point were not repairable. This slide or this photo on the right shows again, a repair of an atrial septal defect. And what they used to do was just push the right oracle through the atrial septal defect and then just suture it in place.

Again, really, really clever, kind of desperate times call for desperate measures. Later on, they started doing a procedure called profound whole body hypothermia. And what they would do is that they would submerge a patient in an ice bath, and then by submerging the patient in the ice bath, it allowed them to open the heart for periods of up to 20 to 30 minutes, without causing any damage to the heart or to the brain, because the metabolism will slowed down so much.

And the way that they Originally came up with this idea is that people that fell through the ice, particularly children, could be underwater for 45 minutes or an hour. And as long as they were heated up slowly, they could make complete recoveries within a few days. So, that's what promoted the idea of perhaps doing a profound whole body, hypothermia, in order to repair cardiac defects.

There were a few animals that were treated in the same fashion, probably in the 60s and 70s, but the problem was that the myocardium in dogs was much more sensitive to hypothermia and you had a lot of issues with really severe arrhythmias that sometimes they couldn't recover from. So I was very privileged in my training to come across a man named C. Walt Lillahi.

And C Walt Lillahi was a cardiac surgeon and he's actually a founding father of cardiac surgery. And he, his idea was that he would connect a child with a heart defect to a parent, of the, that same child, and they would basically just, just re-establish placental circulation. So they would connect the femoral artery of the adult to the aorta of the child and then the femoral vein of the adult to the vena cavas of the child, and And by doing that, they were basically again re-establishing placental circulation and were able to correct numerous cardiac defects.

And CWO Lillahi operated on 45 pairs of patients between March 1954 and July of 1955. And out of those 45 patients, he had a 66% 30 year survival time, and all of these patients had inoperable cancers up to that point. When I, started studying this, I, asked my, or I mentioned it to my dad, and he said, see Walt Mlahi is still alive.

And so I called him up, and we actually became friends. I went up and spent 3 weeks at his laboratory in Minnesota, and he came down from my master's defence defence in Blacksburg, Virginia. So again, very privileged to have made that connection.

This is Sew Lillahi. He's the surgeon right here in the middle, and this is the first pair of patients that we're, being operated on using. Controlled cross circulation.

And so that is the adult on the right-hand side over here, connected by the femoral artery and vein. And then this is the patient who's being operated down here. That patient lived for 9 days and then died of pneumonia, but, overall, the surgery had been, or, or the, the primary issue with the surgery had been a huge success, and it just opened the door to, operating on the inside of the human beating heart.

So, this is Se Wat Liahide back in the day, and these are two books that are, about him, the genius of Seton Liahi, and then the, King of Hearts. It's the true story of the Maverick who pioneered open heart surgery. And if, if you have any interest in the history of cardiac surgery, both of these books are really, really exciting and interesting.

They're both available on Kindle. So the general idea with cardiopulmonary bypass is Basically, you're trying to operate in a bloodless field, and you're trying to protect the heart, and the rest of the body so that it won't have any damage when you are operating in that bloodless field. And so the main parts of open heart surgery are draining the venous blood into a reservoir, pumping it into an oxygenator, filtering it, and then pumping it back into the aortic arch to perfuse the rest of the body.

Sometimes you can use what's called called Cardipoliia, which is where you infuse the heart with a paralytic solution that #1, protects the heart, #2, stops it from beating, so that you can operate in a more precise fashion, without the heart jumping around underneath you. Now, later on, they progressed to using oxygenators, and this is one of the early blood oxygenators right here, which is a huge device that took up half the room, had all kinds of other problems like potential for air embolism, activation of platelets, and that kind of thing. And so, they moved on to a bubble oxygenator, which was much smaller.

So this was the whole device here. And, and so what you would do is you would bubble both the oxygen and the blood through a foam, and then, that would allow exchange, gas exchange, of carbon dioxide and oxygen, and then the philtre would philtre out the bubbles and then it would be pumped back into the patient. Now, this is a modern cardiopulmonary bypass machine, which has all kinds of pumps in it for harvesting blood that's coming out in the field so that you can reuse it.

This is the entire oxygenator down here, that's the, the Venus reservoir and and so clearly this is a much more advanced and much more precise piece of equipment. And this is kind of the setup with all the different pumps that you have down here, pumping in the cardi pelagia, collecting blood out of the ventricle so it doesn't get overinflated, sucking out free blood that's in the chest cavity, and then pumping arterial blood back up into the, into the aortic arch in the patient. Now, this is a man named Asami Uchi in Japan, and he is a real pioneer in veterinary open heart surgery and he has operated on over 1000.

Small dogs with mitral valve dysplasia. And he does mitral valve repair, and he's had somewhere around 95% success rate. His team actually travels all over the world to perform cardiopulmonary bypass in dogs.

And it's very exciting because the majority of patients that need heart surgery, in animals do have mitral valve. Dysplasia or endocardiosis. And, the, the problem that people have had in trying to manage that is that these, these patients are typically very small.

They have a high, thrombogenic potential, and, a few other things. And Masami, Uchi has managed to get past all that and, and have a very active and success. Open heart surgery programme.

And so this is one of his patients here, a little bit simpler than, than the human patient that's at the beginning of this presentation, but still fairly complicated. And remember that some of these patients are 3 or 4 kilometres, sorry, 3 or 4 kilogrammes in weight. And so, clearly this is very, very challenging.

There's a surgeon at Colorado State University named Doctor Chris Orton. And again, I had the privilege of working with him when I was at CSU, at the time, he was doing about one open heart surgery every 3 weeks, mostly for aortic valve replacements and aortic stenosis. He did it a few mitral valve replacements when I was there.

But he has developed a procedure which is called, mitral seal, and let me see if I can get this video going. So I'll turn the volume down here. So basically, the idea with this is that, they are Putting in a mitral valve through the wall of the ventricle.

And so, instead of having to put them on open heart surgery or open cardiopulmonary bypass, you're actually replacing the valve through a very small hole in the ventricle. And this was developed at Colorado State University and they are going through clinical trials right now. And so you can see that they put in a little anchor at the tip of the left ventricle.

And then they're going to insert a valve that basically the whole thing is only about 3 or 4 millimetres in diameter, and then they inflate it or open it up like a, like an umbrella, and that is functioning as a complete valve replacement. So here comes the valve, in its collapsed form. And then, you'll see in just a minute that they're going to inflate it or open it up, and then using sutures that are attached to the valve, they pull it back down into the annulus and then just anchor that to the, the wall of the ventricle.

Very exciting, potential, for future of open heart surgery in dogs, and I am personally on a waiting list to get trained in doing that procedure at some point in the future. So you have this disc on the outside of the heart and that acts as an anchor for the for that replacement mitral valve. This is, kind of the, more advanced human open heart surgery now where they're doing the whole procedure now through a tiny, tiny little incision, which is only about, 5 centimetres across.

And they can do the entire, cardiopulmonary bypass through this very small incision. So that's the way things are going, more and more minimally invasive, as they progress. This is another very exciting advancement in human medicine where they can put in an entire, this is an aortic valve replacement that they're putting in completely through the femoral artery.

So the whole catheter, this whole thing is coming in through the femoral artery and then it's just basically inflated using a balloon and locked into place. And so the patient doesn't have to have any, you know, any surgery at all, except for a small incision in their femoral artery. So again, this is the direction that things are going.

One of my sons is very interested in being a cardiothoracic surgeon. He's 2 years out of medical school, but there is a concern that a lot of the procedures that used to be done as an open surgery now are being replaced by, by the interventionalist, interventional cardiologist and radiologist, and that the place for a cardiac surgeon is, is diminishing year by year, again, because of their ability to do these things in a more, minimally invasive fashion. So, I'm gonna switch gears a little bit.

I'm gonna talk to you about a case, patient that, I came into contact with, which was a 61 year old human male, happened to be a cardiovascular surgeon, and he happened to be my dad. And so he was in Europe, on one of his first vacations he had taken in the last 30 years in some He had a, a massive stroke. And he was on, put on an aeroplane, taken back to Florida, where he was living at the time.

And, he was, he was totally paralysed on the right side of his body and could hardly speak, because he had, what's called Broca's aphasia, because he had, a stroke of this part of his brain. And he got into an argument with the radiologist, again, barely being able to speak, saying that he had an operable lesion and the radiologist said he did not have an operable lesion. So he discharged himself, put himself in an ambulance to the Mayo Clinic, asked for a different study to be done.

They did a different study and found that he had a 90% occlusion of his middle cerebral artery. And so they did a procedure, which is very interesting and exciting. They made a hole in the side of his skull and then attached his superficial temporal artery to the middle cerebral artery, distal to the occlusion.

And I asked the surgeon what the success rate of the surgery was. And he goes, he'll Be operating again in 2 months. And I said, Oh, what's the mortality with this procedure?

And he said, Oh, there's no mortality at all, which I don't have that kind of confidence when I talk about cruciate ligament repairs much less, you know, a major brain surgery like this. And true to this, surgeon's word, my dad was operating again in 2 months. So, again, this is the type of anastomosis that they did superficial temporal artery to the M4 branch of the middle cerebral artery, and, and just incredible microdissection, these vessels are maybe 2 to 3 millimetres in diameter and in a hole that's about 6 centimetres deep.

So incredible technical skills that these surgeons have. So, this is, again, a view of the superficial temporal artery, on the side of his head just in front of the acoustic meatus, right here behind the parotid salivary gland. And so, again, he had a, a hole in the inside of his skull and that they, they, passed the middle cerebral, I'm sorry, the superficial temporal artery through.

So this is, an example of the operating room of the future, and I'm sure that any of us would be really jealous, of this type of theatre and the opportunity to operate in a facility like this would be amazing. So this is a human facility. Every, you know, almost everything's hanging from the ceiling so that you don't have, so many cables on the floor.

You have, invasive, the, the CR and fluoroscopy unit here, and they can do all the invasive procedures, in the theatre and watching in real time what they're doing. So this is kind of what, a lot of the modern human, invasive theatres look like. This is something that's really interesting, which is 3D navigation, and so what they do is they use infrared beams and They use fiduciary markers on the wall of the on the skull, and then using this, they can tell exactly where they are at any point in time, anywhere in the brain.

And I've had the, again, the privilege of scrubbing in with the human neurosurgeon for a day, and they use this on every single case, be it a spinal case or, a pituitary tumour, or, cerebral cortex tumour where they can tell exactly. Where they're operating at any point in time. Now, this same type of thing has, has been developed for dogs as well.

And so, again, you've got these markers that give the infrared device a point of reference, so that you know where you are relative to those points of reference at any point in time. And so, then you get these, 3 dimensional orthogonal views, so that you can Tell exactly where you're going and what you're trying to achieve. And they can even using minimally invasive techniques, ablate tiny little areas within the brain to, ablate Parkinson's, foresite and things like that.

So, very interesting and exciting, progress in, the veterinary neurosurgical field. I was offered one of these devices, by the human neurosurgeon. When theirs became obsolete, but the problem is it was gonna cost me about $50,000 in, equipment that I would have to use with the device in order to make it functional in my practise, so I, I elected to turn them down.

Another area which is challenging in neurosurgery is just holding the skull still, and so they've got these screws that actually go into the patient's skull and hold the patient absolutely still. We have a challenge in veterinary medicine that the, the irregular shape of the dog's skull can make it difficult. To, to position the skull accurately.

And so they've developed again a similar device in veterinary medicine, and these reflective balls are those fiduciary markers, which then, use the infrared, 3D localization device so that you can tell exactly where you are at any point in time during the neurosurgery, and then also the benefit of these articulated arms, which again allow very precise and stable and repeatable, positioning of, of the surgical instruments. Now, another area in human medicine, which they're much, much more advanced than we are in veterinary medicine, is determining the focus of epileptic, epilepticogenic, epilepticgenic, centres in the brain, and they can actually map out the entire surface of the brain in real time and determine exactly where the seizure is coming from, and then they can ablate just a tiny little area of the brain. And so, epilepsy or anti-epilepsy surgery is very, very advanced in human medicine, much more so than in veterinary medicine.

One thing that I found really interesting when I was scrubbed into neurosurgery on the day is that the surgeon was operating on the brain and the brain was feeling too much of the calvarium or the, the skull. And so they were having difficulty viewing. And so the anaesthetist had this little tap in the spinal fluid.

And basically, the surgeon asked the anaesthetist to drain out 10 mLs of CSF. And so the sur anaesthetist drained out 10 mLs, and the brain basically deflated away from the skull, and it made it much easier to, to operate to see exactly where they were working. So that's something that we have not done in veterinarian medicine, to my knowledge.

It's certainly something that would be very helpful in some of the more, intense, brain surgeries, and more technically demanding brain surgeries that we might be doing. So the other area that has made lots of advancements in veterinary medicine is pituitary surgery. And pituitary surgery primarily is for pituitary dependent Cushing's disease.

There's a structure that's really important. You've got the cavernous sinus around here, and then you've got the circle of Willis, which if you penetrate the circle of Willis during pituitary surgery, it's very, very Serious and can often, result in death. And so, identifying from external landmarks exactly where the circle of Willis is in order to find the pituitary is a very challenging aspect of pituitary surgery.

So, it's called hypophysectomy, a complete hypophyectomy, that they do. In dogs and cats for pituitary tumours. And the guys in Utrecht in the Netherlands are probably the masters of, that type of procedure, and they've done hundreds and hundreds of them.

And what they've, determined is that the success rate or survival with pituitary hypophysectomy is better than medical management of pituitary dependent Cushing's disease in dogs. And so, there was a study that was done again by the guys in the Netherlands, that was published several years ago. We can see the, hypothesis down here.

This is Rostral, this is codal, brain stem is sitting down here, that's the optic chiasm right there. You can see the cavernous sinus around here, puriform los lobes of the brain here. Olfactory lobes over here.

And then, and you can see how small an area is and how difficult it would be to identify this from external landmarks that you could see on the skull. So the transphhenoidal hypophectomy means that they're going through the sphenoid, which is in the root of the mouth. Again, the, the big issues that they're having now, the surgery technically is not that difficult for them.

The main issues, are the medical management afterward, because, these dogs. Are, have, lots of endocrinopathies, including, diabetes and sipitus and a few other things that they have to manage. But inexperience and survival times are equal to or superior to medical management of pituitary dependent hyperadrenal corticism.

There is a very steep learning curve. I've done about 5 of them, and, I think that 3 of them have been successful, but it is a very challenging surgery. And so, this is a study that was done, many, many years ago, where again, they're trying to determine exactly where the pituitary gland is gonna lie in the celloursica from external landmarks through the roof of the mouth.

And so you're using things like that. Haullus, which is the structure down here, you can palpate that on the roof of the mouth of dogs, using, trying to use that as a reference point and then burning down through the cell at Tursica, and then identifying that pituitary, tumour and removing it. So these are illustrations from another study that was done, using CT landmarks, and then they placed the patient in, in this position where the dog's mouth is on a, on a stand, and the, the mandible is pulled down ventrally.

You cut through the soft palate and then get down to the, the, bone, the sennoid. And then, drill a little pilot hole and then use a burr or a kerose on jure in order to identify exactly where the cellatursa is in the pituitary gland. Here, they're using what's called an exoscope.

We've got an exoscope as well, which gives you really nice visualisation from a distance of what's going on inside, inside the dog's mouth cause you're working in quite a deep hole. So this is a, an MRI of a dog that has a pituitary mass up here. This is the, interthalamic adhesion, third ventricle up here, cerebellum is up here, brain stem, cerebral cortex.

There's the corpus callosum right there, and this is the large contrast. Enhancing pituitary mass on sagittal and axial slices, and then they've gone in, done the transfinoidal hypophystectomy, removed the pituitary mass. You can see that on both the sagittal and the axial slices.

There's a, neurosurgeon at Colorado State University. I think her name is Linda Klopp or Laura Linda Klopp. And even back, this is 13 years ago, she published a study of endoscope-assisted intracranial tumour removal in dogs and cats, 39 cases, and she had a median survival time of over 6 years in dogs with meningiomas, which is the longest survival time ever published.

And what she was doing was Using the scope to go in and, and, and almost microscopically identify and remove residual tumour. And so, so for forebrain, again, forebrain meningiomas, which is where we see them most commonly, Her median survival time was over 6 years. And even in hindbrain, meningiomas, she was getting survival time of, of around 2 years.

So, I'm very excited. Now. When, I bought my first CT scan back in 2005, for some reason, so it was, it was the most widely available imaging in Melbourne, Australia.

And so as a result, I started getting tonnes of epilepsy cases where people would have dogs that were having seizures. They'd send them to me just to image them to see if there's anything obvious going on. And at that time, there was no MRI available for, for animals, at least not widely available.

And because I started seeing These epileptic epileptic patients, as a surgeon, I started thinking, you know, is there anything surgically that I can do for epilepsy in dogs? And there was a procedure that was done, a while ago, not, not done that frequently in humans, where they actually divide the corpus callosum in half. And I'll show you, this is the corpus corpus callosum right here.

It's this structure up here, and basically, it connects the right and left hemispheres of the brain. And the thinking was, That in people that have severe and refractory epilepsy, these seizure starts in one part of the brain and then propagates across the corpus callosum to the rest of the brain and becomes a grand mal seizure. And so, in humans, they were splitting the corpus callosum, and so I thought, maybe this is something I could do as well.

And it had never been reported in animals in the past. There was one laboratory study done in 6 Beagles where they, did a, a corpus callusotomy in normal dogs and found that 5 out of 6 of them were pretty normal within a day or two of surgery. And the challenge that they had was that retraction of the brain in order to get to the corpus callosum, was causing neurologic deficits afterward.

And so then I used Linda Klopp's study using endoscopy, and the idea that we could maybe reintroduce this corpus callisotomy, I operated on 10 patients, With idiopathic epilepsy, and basically, the owners had to tell me that the, they were, about to euthanize the dog because of refractory epilepsy, and that was my signal that it's, something that I would be happy to do because it was an unproven treatment. The other thing is that I didn't charge the clients anyway. So this is our first patient where we're dividing the corpus callosum using an endoscope.

And you can see here that this is actually a cross section of the corpus callosum right here, and I'm dividing it with a freer elevator. Now, when you do, encephaloscopy, there are structures that you see, like these are the middle cerebral arteries that, like the one that my, where my dad had a stroke. And these are a millimetre in diameter, and we can see them, they're absolutely huge.

You can see them pulsing away here. This is the column of the fornixx, which is, through the corpus callosum in front of the thalamus. This is actually the inside of the lateral ventricle of the brain of one of my dogs.

And so this is an area that you'd never expect to be able to see as a surgeon in your lifetime. And, I, I felt like I was, you know, the first man on the moon, when I, when I first, and entered the, lateral ventricle with my scope and was able to see this. This is the choro plexus within the lateral ventricle of one of my patients.

The other thing that we, developed through our brain programme is that, I'll give you an example. This is a fairly large, meningioma in the cerebral cortex near the piriform lobe of a dog. And so a challenging approach, if you went through a, a typical rosal tentorial approach, which would be through here, you'd have to travel through all of this.

Normal brain tissue in order to get down to the tumour. So we developed a new procedure, which is where we cut the zygomatic arch and the vertical ramus of the mandible, and then that allows us to do a craniotomy, which is much farther ventral than would normally be allowed in our, my resident at the time, Dr. Kath Duncan, published this.

And, in a couple of cases, and we got a lot of positive feedback from that, in that it is a very viable, option for operating these tumours that are far ventral in the brain. And my, my doing this comes from my being a cancer surgeon, where I know that we can remove the zygomatic arch and the vertical ramus and the mandible for skull cancer without any problems. So then, I just kind of repurposed or reapplied this procedure for getting into the calvarium in order to remove brain tumours.

One thing that's making huge advances now in veterinary medicine is radiation therapy. And now we've got two amazing pieces of, of equipment in Australia. we don't have one of them at our practise.

We have a very, archaic, radiation therapy. And the problem with radiation therapy is that when you're trying to treat a certain area, for example, For example, this would be the pituitary and the dog, that you have all these important structures around the brain, which you have to penetrate in order to get to that structure. And so, using computer modelling, and several different ports for the radiation therapy, they're able to target exactly the lesion without affecting any normal structures at all.

And so their, their, their isodose, curve is really, really specifically targeting the pituitary gland in this particular case. They can do, you know, stereotactic radiosurgery, and all kinds of things where they can preserve structures within a couple of millimetres of the tumour at risk. And so, again, I don't know if this is gonna be wide, widely used in all veterinary cancers, but in human cancer surgery, they certainly are reducing the number of cases they'll operate on and instead try to do stereotactic radiosurgery, in, you know, instead.

So this is the isodose curve from, radiation therapy of a brain tumour. And so the red area is getting a therapeutic dose of radiation. Anything that's not red is getting, you know, fairly innocuous doses of radiation here.

And so you're concentrating a huge amount of radiation in the area of interest, and the rest of the brain and the rest of the body are getting hardly any radiation, at all. And so the side effects are markedly reduced. Now, this is, a linear accelerator for radiation therapy that is, on a robotic arm.

And this is something that, is very exciting because not only, do you get to treat from several different angles, but also they can use that same stereotactic, 3D monitoring of the position of the patient, and they can alter the beam of the radiation as the patient breathes. So this is a, a video of that type of procedure. So they've got basically a CT scan built into the radiation machine, and they can change the direction of the beam in real time as the patient moves.

So you'll see this robotic arm come in and, and treat the patient, and it'll move around the patient as it's treating and the radiation oncologist down here can monitor exactly what's being treated, as they treat. There is one of these devices exclusively for animals in New York State, that's the only one that I'm aware of, and this is called the Gamma knife. It's a huge robotic arm, linear accelerator at the end of it, and they can treat very precisely and again account for motion, artefact that you're gonna get, as the patient breathes and moves and that kind of thing.

So here they're treating a spinal tumour from several different directions and again getting only the tumour and avoiding things like spinal cord and important other structures in the area. So, this is something that I find really exciting. This is the isodose curve if you're treating from a single beam in a single direction.

So, the red down here is really hot, meaning that they're getting a lot of radiation here, and then the yellow is pretty cool. And so you can see that if you're trying to treat a brain tumour through a single beam, you're just getting a lot of tissue that's being affected by just as collateral damage. There's another modality called proton beam therapy, which is, the way that it works is that this is conventional radiation therapy here.

So you're getting drop off by depth. So let's say this is depth on the X axis, 1020, 30 centimetres, and this is the dose and the Y axis, you're getting A lot of dough is concentrated near the skin and then it drops off in a logarithmic or exponential pattern, and the deeper you get. With proton beam therapy, they can actually programme the protons to deliver relatively low dose all the way through as much tissue as they want, and then release it only within the tumour just by programming the protons and the energy that they have.

And this is using a cyclotron. And so this is the patient interface for a cyclotron, and the actual device is you've got this huge cyclotron which might be 100 metres across. You get the beam, and then a wave guide that directs the beam exactly where they want it, and then comes up and then delivers the radiation to the patient.

So what you see here is a very, very small part of the entire device that's being used to deliver radiation to the patients. But the benefit is that you're getting extremely accurate radiation delivery and avoidance of normal tissues. And that's always the You know, the goal of radiation therapy is to administer a lethal dose of radiation to the tumour while avoiding normal tissues that would otherwise be damaged as a kind of an innocent bystander.

Now this is a really interesting slide to me. This is, a, a child that has what's called Rasmussen's encephalitis, and with Rasmus, Rasmussen's encephalitis, they actually have an encephalitis that's travelling through the Brain at a very, very rapid pace and they have days to weeks to make this decision. What they do is that they remove the entire half of the child's brain.

And so, this is the cerebral cortex through the craniotomy that's affected. And this is what it looks like when they're finishing, finished removing half the brain. And so they've done what's called a functional hemispherectomy.

That's the corpus callosum sitting there. You've got the thalamus brain stem and the opposite cerebral cortex here. If you do an MRI of these patients, you can see that half the brain is missing.

And what they, say is that if this procedure is done in patients under about 3 years of age, they can be completely normal. If they're over 3 years of age, then they have more struggles. But, I was reading a blog by a parent of a child who was 16, had had a hemispherectomy performed at the age of 2, and he said, you know, my son is on the tennis team.

He's not the first on the tennis team, but he still plays tennis at a competitive level. And if you did an MRI on him, you would see that half of his brain is missing. This was another interesting case that I had.

This is the cerebellum of a dog, and this is a choroid plexus tumour sitting in the fourth ventricle of the dog. So this is normally an area that would be not accessible. And in fact, they went to another neurosurgeon who said that it was an inoperable tumour.

And so, the dog belonged to one of my nurses. I had a look at the MRI and I said, look, I think this is something that we can actually manage. So, let's see if I've got the video here.

No, so, anyway, so what we ended up doing was we actually split the cerebellum. And again, I learned that from the fact that I could split the corpus callosum. The brain is actually fairly, resilient when it comes to those, those types of things.

And so we split the cerebellum and got the tumour out. Through, a hole in the back of the skull, and I've operated now on two patients in that fashion. And both of them have been successful surgeries.

The last one we did is alive for about a year out from his surgery from what was allegedly an inoperable tumour. There's still no evidence of recurrence. If you are interested in neurosurgery, there are two great books that I would recommend.

One is called When the Air Hits Your Brain, which is kind of a semi-fiction, autobiographical fiction of this neurosurgery resident as he's going through his training and just talking about the challenges, that he went through in, getting his, his skills in neurosurgery. And then the other one is a story, called Gifted Hands, which is about Ben Carson. And Ben Carson, was a presidential candidate in the United States, and he, came from basically the projects in, in Chicago and had some life-changing events where he decided to make something, of himself, guidance from his mother and that kind of thing and became one of the pioneering paediatric neurosurgeons, today.

So, anyway, both very interesting books, and, I'd encourage you to read them, both available on Kindle. That's pretty much all I have. And so if you have any questions, I'd encourage you to send them through and I hope you found this presentation interesting.

Thank you very much.