Hi and welcome to this webinar on bovine thoracic ultrasound. So the plan for this webinar is to think about patient preparation and really not underestimate the importance of that. We're gonna think about some of the principles of plural ultrasound and where you are in the luxurious position of having a choice about ultrasound machines and setups, we will touch on that as well.

The focus of this webinar is going to be about BRD, but we are gonna have a at least consideration of lesion distributions and causes of diseases in different age groups as well. Then I'm gonna give you, hopefully, lots of examples of normal and abnormal images that we can obtain on thoracic ultrasound, touch on the scoring of lesions for BRD and why that's important, and give you some case examples. Now some of you may have done courses where you've done, practical sessions.

Looking at thoracic ultrasound in sheep that have got the diagnosis of yardscieta and right at the end, I'm gonna try and finish off talking about making sure that you've definitely got lesions, be that with BRD or with yardscieta, and that you're not sort of misinterpreting normal structures. So, the what and where, and the what and where often when we're on farm is dictated to us. But in an ideal world, we would be in a good dark environment.

When we're dealing with animals that aren't too, hairy, we can get away without clip. But if you, particularly if you're looking at individual animals rather than groups, sometimes having really great clippers, especially if they're really hairy, will not only improve your image quality, but will speed up the exam that you do. If you don't clean, the very least that you can do is sort of clean the hair off.

And I find you can get pretty good, contact with water, especially in the not too hairy animal. In terms of using, alcohol based products, certainly you can, you do need to be aware if you're doing groups, how much alcohol you can carry in your car because obviously it's flammable. And also remembering that we can get probe issues, particularly on some of the older machines, older probes anyway, that it can have impacts on the glue.

And then in an ideal world, and you can't get great enough pictures with water, then thinking about using ultrasound coupling gel or KY jelly, do your very best to avoid using rectal lube. You get very poor quality images and it's really tough to get off the coats afterwards. So other useful things are trying to minimise impacts on image quality by turning off electrical instruments.

So mobile phones can certainly cause noise, especially if you're using wireless ultrasound systems. And try and make sure your machine's not freezing. And warm it up beforehand.

And I mean, this is one of those situations which is, singularly unide ideal. We're outside, it is a sunny day, which was the only saving grace, but it was so sunny trying to see, any form of image quality of image on the, on the ultrasound, machine was pretty tough. OK, so that's patient prep.

Frequently we're just gonna have to adapt to the situations that we've got and the time that we've got available to us. Now we're gonna move on to think about principles of plural ultrasound, and lung ultrasound is largely based on interpretation of artefacts produced at the plural surface. And these artefacts primarily relate to how the ultra the way the ultrasound beam and the air interact.

And you have to remember that air is ultrasound's enemy and therefore ultrasound is not going to be able to penetrate into the lungs, which means we're only going to pick up lesions that are gonna be in contact with that visceral pleural surface. So that means if we've got pathology deep to that air and we've got a large No, plural, interface, we're not gonna be able to see those. But luckily, with many of the diseases we think about in cattle, quite a lot of that pulmonary pathology does involve the plural surface to some extent, so we're able to not only visualise it, but also, characterise its extent.

And we can use ultrasound to look at the majority of the plural surface, and with the exception of the mediastinal reflections. And what probe you choose and the technique you use depends a little bit on clinical suspicion and circumstance. If you had got, say, an individual valuable animal and you wanted to explore the whole plural surface, then you might want to start cordially at the 11th or 12th intercostal rib space, and you might want to slide down each rib, in turn, moving cordially to cranially.

But if we're doing scoring, for example, for BRD, we might just want to look in that one window, that cranial ventral window, where we're going to see majority of our lesions. And it's really important that ultrasound isn't used as a standalone modality, that we get lots of overlap between different conditions. And so it's really important that we integrate the clinical picture when when interpreting those, those plural ultrasound images.

So hopefully this video is gonna play. And this is showing you a largely normal plural surface. I'm gonna try and point as we go.

So we've got skin and intercostal muscle. We've then got parietal pleura here, we have a small gap, and then we've got the visceral pleura. Everything below 1 centimetre on this image is an artefact.

And we use that artefact, those horizontal. Lines to tell us that that plural surface is largely smooth. Now you will see there's some very, very small, comet tails coming down here and, In large animals, particularly ones that are living in barns, this becomes almost a variation of normal, and you'll particularly see it on the edge of the pleural surface as you're moving from thorax into abdomen.

So now we move on to the next image. This is also a plural surface image. So again, we've got skin, we've got fat, we've got intercostal muscle.

We've got, again, parietal and then visceral pleura. And you can now see we've got these very, very small areas. That are, if you like, causing a deflection in that visceral plural surface and are giving us these comet tails.

This would be a, a very mild, mild surface consolidation, probably not something that would be clinically significant in most of our patients. So, let's think about lesion distribution. So when we're evaluating animals, we can think about where we're gonna get lesions based on whether that is likely to have had an inhalational root, or whether it's likely to have had a hematogenous root.

So when we're thinking about this sort of cored dorsal region. It's much more likely to be hematogenous. When we're thinking about this sort of cranio ventral region, we're thinking much more likely to have had an inhalational aspiration, component to it.

And then when we're in this sort of perihila region, it can be either, although it's usually vascular. So what sort of diseases have we got that we're gonna think about? So when we're thinking about maybe the younger animal, we've got sepsis, usually secondary to failure of passive transfer, and we can see lesions throughout the whole lung, particularly in that corner dorsal area.

When we move on to bovine respiratory disease in calves, it's gonna depend a little bit what the pathogen is that we're dealing with. So as you can see, I'm not gonna go through this list in a great deal of detail, a large number of them. Are gonna cause lesions in that cranioventral region, but we will see lesions also, particularly with BRSV and malignantcaral fever, we can see those more generalised throughout the throughout the thoracic cavity.

And then as you can see again, when we're dealing with things like M bovis, we can also see cardiac changes as well, not only pulmonary ones. When we move on to think about maybe the older care, not necessarily, but we're thinking about TB. Normally we'll get generalised millary lesions.

They've usually, some of it's inhalational, some of it's gonna have been hematogenous, but we'll largely see lesions throughout the, throughout the lungs. And when we're imaging them, we can often pick those up much more easily in that cordo dorsal region. When we're thinking about lung absence is secondary to Sara, we'll often pick those up in that perihila region.

And then when you move on to things like fog fever, interstitial pneumonias, we're gonna get lesions generalised. And then dictiacorlus, we're gonna see much more lesions in those cordo dorsal lung areas. And so they're the ones where we're looking for changes in the, in that plural interface, as it were, but also with a Ultrasound, particularly if we've got slightly more penetrative ultrasound machines, we can pick up lesions in the mediastinal regions, thymomas in younger animals, abscesses, spontaneous lymphoma, which luckily isn't too common.

And then we can use our ultrasound machine to identify cardiac abnormalities, pericarditis. Endocarditis and sometimes myocarditis. So I thought I would go through this classification of lung ultrasound consolidation, and this is put together by a small animal, primarily ECC clinician and ultrasonographer called Greg Lazandro.

And these are images taken from small animals, which is why you can see ribs, but it really does highlight the lesions that we're gonna see. So when we start with A, we're gonna be picking up what we've just talked about, that normal glide sign plural surface with those horizontal artefacts that we see below that visceral pleura. When we start to get wet lungs, and we probably do see a number of wet lungs, secondary to, secondary to cardiac disease, often in cattle, we start to see these sort of rockets or comet tails, and they're often very, very ecogenic.

And then we move to perhaps the C and D, which are the more common signs that we'll see with BRD. The shred signs are where we've got these, we shouldn't use the term air bronchogram in ultrasound, but it does describe you can see the air trapping within the bronchioles. And then D, where we've probably got more either severe or more long standing disease, where we're gonna pick up these tissue signs.

And then when we're thinking about nodules at party, in my mind in an adult care, TB is gonna be pretty high on the list, but also it could be it could be abscess or other forms of granuloma. And again, this is this is taken from this vet blue diagnostic algorithm. Some of this is not relevant to the cases that we see, but some of it certainly is.

So if you're imaging the chest and you can see a plural line, but you have no glide sign, it might be suggestive of pneumothorax and ruptured bully with BRSV. And then when we think about non trauma, which are gonna be the cases we're gonna see most likely in our patients, where we start to see these sort of comet tales, they're described here as beelines or rocket signs, then we're likely to be dealing with potentially edoema or much more likely pneumonia. And then when we start to get those shred and tissue signs, we know we've got areas of consolidated lung, and they're likely, in our case, to be caused by pneumonia.

So what about pneumothorax? And, you know, most of the time in, in bovine practise, we're not going to treat pneumothoraxes unless it's a particularly special animal. And when we've got pneumothorax, we'll often see a more thickened parietal pleura, but most of the time it's just not gonna glide.

So it tells you that you've got a problem in the, you've got air in the, plural space, and then If you were in that situation where you've got particular animals that you wanted to treat, it allows you to, choose an appropriate position for drainage, and then you can monitor successive treatment, which is really, really helpful when most of us are not gonna have X-ray on the farm. So now I thought I'd go through some cases, and I apologise for the quality of this image, we could definitely have had our depth reduced more to about 5 centimetres. But what you can see in this, animal, this was a, I'll show you a picture of the cow in a minute, or the cows in a minute.

This was an animal that presented in respiratory distress. We've got these really hypoechoic comet tails, which are indicative of pulmonary edoema. And you know, these are the sorts of cows that we've got, both of these have got got pericarditis.

And then this was a cow that presented having, having had an altercation with a car. The, it was a, it was a beef animal. It wasn't particularly sick.

And it came in and maybe it's respiratory rate was up a tiny bit, but it had been hit by a car. And so, but actually, when we, when we put The scanner on this cow, you can see this up here is the, parietal pleura. This here is the long edge or the visceral pleura, and I know this is a still image, but it doesn't take a lot of imagination to imagine that that's swirling and filled with, blood.

We drained this blood, we gave it back to the cow via an autologous transfusion. The cow never looked back, it never, it never bled again. One treatment was plenty, and that's the cow, and that's what it had, done to the car.

So now let's move on to think about bovine respiratory disease, and I've put this particular calf health scoring system up simply as a demonstration really, but, there are many others available. And this one's quite nice in that it combines clinical parameters as well as ultrasound scores that we do. Now it's downside is you need to look in more than one spot.

And depending what you read in the literature, sometimes the literature has suggested that lesions are likely to be unilateral, and that's explained by the way that the main stem bronchi come off the trachea in an asymmetric fashion, whereas if you read other studies, they've shown that actually you can get lesions on both left and right sides. Now, from an ease on farm, when you're, when you're screening groups of calves, it's easiest to position yourself on one side and have some sort of race where you can work down. And probably starting on the right is a good option, but sometimes there will be animals that you're gonna miss.

And the idea with this ultrasound, this particular ultrasound score where it doesn't look in one region, is that we are, we're trying to look at how many lobes of the lung are affected. So you sort of fast scan two or three spots on each side so that you get an idea how severe the pneumonia is. Now, lots of people will just recommend scanning in one spot, on that right hand side, and there's been some really good data showing that lesions that are more than 6 centimetres squared are likely to have an impact not only on growth rates in beef animals, but also on milk production in in dairy cows.

In their later years after they have, had this as, as calves. So you might want to use this in order to identify problems, but also quite a good system for scoring calves and deciding which, which heifers you're gonna keep as replacements and which ones you aren't. And also So sometimes to know when to quit, you know, those calves that perhaps haven't grown very well, they've had multiple, courses of antibiotics, they've perhaps moved down a, moved down a group in terms of, an age group.

You know, sometimes it's just easiest to say, these are lesions we are not gonna be able to fix and therefore we need to, we need to cut our losses. Now, what I didn't talk to you about at the beginning was use of your ultrasound machine. So most people are gonna have, easy scans that they will have available to them, and you can get some really, really great pictures on your Easy scan.

So it's always worth starting in early pregnancy mode, and then it might be you need to move to late pregnancy mode if you're, if you do find lesions and you want to try and characterise how big they are. Anyway, the next and last part I suppose, of this session before we get onto the things you must not mistake for lung lesions, I'm just gonna go through some examples of, of BRD and perhaps talk about some of my thoughts on decision making. So this first one is perhaps a bit more severe than the early example that I showed you.

So majority of these lesions are taken in the cranio ventral lobe unless unless I specify otherwise. So you can see that there's quite a large number of . Of comet tails or rocket sciences coming down, suggesting that that plural surface maybe isn't that happy, but that this is really nothing to, nothing to worry about.

This is again another example of a mild lesion. This lesion's taken a little bit more ventrally, and we just have to be a bit careful when we're interpreting these cos sometimes we pick up other structures that can look like consolidated lung. But again, this surface doesn't look particularly smooth, but we don't have any areas of consolidation.

So then we start to move on to the sort of more I suppose exciting lesions that we've got. So here we've got a shred sign, so hopefully you can see that we've got normal plural surface here on the left. Then we've got a region, and this is only probably about 1 centimetre squared, and you can see that this lung is consolidated and it's solid, and we've got some gas tracking within it, like we talked about airborne for brands.

So again, this is a pretty mild lesion based on the extensive literature we've got. It should have, it should be treatable and have no impact on that, on that animal. Assuming it responds well to treatment.

Again, this is another mild to moderate lesion that we've got here, and the lesion's focused on this sort of left-hand side of the image. We've got quite a lot of comet tails here, and a sort of smallish lesion. Again, only about probably 0.5 centimetre in diameter.

So, although the area of lung is quite dramatic to look at, the lesion size, assuming that's the only one, is pretty small. And then we start to get on again, this is perhaps a, quite a spherical lesion that we've got here. We've got more surface consolidation, and again, we've got this gas trapping sitting within this piece of consolidated lungs.

And then this lesion is a really tricky one to interpret. You have to be really careful not to overinterpret this, particularly, you know, in less than optimal conditions, perhaps if you've not been able to, you know, get really great contact. So this is a piece of lung that's sitting really cranial eventually.

And if I orientate you, this is actually hot sitting here. So we need to not make this into a lesion, or we're gonna end up saying that this animal's got a much bigger lesion than it has. When in fact the lesion that we've really got is this area just sitting, just sitting here on the left hand side.

So it's actually, again, it's maybe 1 centimeter.5 in diameter, but it's not too big. And this is just a still image of that same picture.

So we've got hearts sitting over here on the right, and then this is our, this is our area of consolidated lung with these air bronchograms. And then we're gonna start moving on to the more, more severe, not necessarily clinically significant, that can only be determined when you've got that animal in front of you and you know what it's history is. But again, we've got some rocket science here.

And then this is, this is our lesion, just sitting in here. So we look like we've got some, it's slightly more hypoechoic at the top and then a little bit less hypoechoic further down. And we're starting to get to, like, again, 1.5 centimetres.

If this was this animal's only lesion, again, prognostically in terms of, future performance, it should be fine. And again, here we're starting to, we're gonna start to want to start measuring when we've got lesions like this. So it's probably 1 centimeter.5 down, but if we measured across, we might be looking at maybe 1.5 by 2 centimetres.

Again, theoretically shouldn't cause a, shouldn't cause a long term problem with these animals. Now, the key here to this image is where I've labelled. So this image was, I always start cranio ventrally and then if I find a lesion cranio ventrally, I sort of go hunting a bit more dorsally and a little bit more cordially in order to look at the extent of the lesion.

And so this is actually a second image that we took from this, from this calf. And what you can hopefully see, we're up into this middle lobe, so we're up into lobe number 2 being affected, but if you look at the scale down the side, we're starting to have a lesion here that's probably 4 centimetres in depth. And again, if you come across, probably.

About the same. And then if you then piece that together with the, the little bit that was, that was more caudal, we're now starting to get lesions that are likely to be impactful. This would be an animal that wouldn't be for me, appropriate to keep as a replacement heifer, and depending on how it was doing, whether it was worth investing significantly more time in it.

And again, so this is a cranio ventral lung, but we're starting to see much more difficult to establish exactly where the edges are. You can see I haven't quite got the, got the, the lung tip on here. So again, this would be another one of these lesions that was, that would be clinically significant.

This animal was pretty small for its size and had had, had had treatments that had been ineffective. And then we start to get to the severe ones, and these lesions are called they are described as hepatization. So this is in fact lung, but it's got that appearance of liver.

So we've got largely normal lung here on the left hand side, and then we, we get some, we get some comet tails here, and then we've just got this solid piece of tissue. So more severe. It may be impacted by the type of, organism involved in this, but more chronic.

So, again, if you start looking at the depth that we've got here, we're gonna have a lesion that's gonna be bigger than, that's gonna be bigger than 6 centimetres squared. We advise the farmers not to carry on with this, this animal. And then we get this beast, and, I never like to make diagnoses of abscesses on ultrasound because it's not an ultrasonographic diagnosis, but you would be as sure as you could, again, we've got hepatitis lung, you would be as sure as you could.

That this was likely to be an abscess here, possibly one here, maybe a third one here. And again, this was an animal that hadn't responded to, to therapy, was very small for its size, and again was 1 to, 1 to add to the call list. So, I'm now gonna talk to you about some of the things, the other structures to be aware of that you need to not muddle up with consolidated lung.

So this is an image that especially if I could freeze it just about there, that you look at this image and you think, well this looks like it's a piece of consolidated lung. But actually you're really, really low down here and you're actually picking up some stuff in the mediastinum, but you're also picking up the . The right ventricular free wall, and this up here is an, an extra thoracic muscle in transverse section.

We've got blood vessels sitting up here, so it's really important that you realise that probably you're right on the edge of, being in the thorax, and, but none of this in this, in this image that we've got here is in fact lung. I showed you this image, before. You can see you've got some consolidated lungs here.

And we've got some, very mild consolidation. And then you look like what looks to be quite a big lesion. And if you were going to measure that lesion, it would probably be maybe 2.5 by 2 centimetres.

But again, you're really low down here, probably quite a long way forwards. And again, you're picking up the heart. The lung pathology in this case is is very, very mild.

And again, this is another one that can be really tricky, particularly if you've got beasts that aren't standing very still. I showed you this image in the previous ones. We've got a very small area of consolidated lung, which is of no consequence at all.

And then again, you're picking up heart muscle and blood within the ventricle. So again, not to be overinterpreted, not clinically significant. The purpose of this image is to show you that when you get really, really ventral, you find that the lung tapers off and that you can then start making up lesions that are sitting sort of what appears to be, within the lung but are actually above the, the parietal pleura.

I think I've got a better one. To show you of that here, right at the edge here. So again, this is very mild changes that you've got here, really important not to overinterpret what we've got sitting above that parietal pleura.

And again, right on the edge here, really ventral and cranially, again we've got some mild changes, right at this lung tip of no clinical consequence. And then this area here that you might want to make into consolidated lung, again, is in fact heart. And one of the tell tales about, have you got, have you got the, The visceral pleura and a glide sign or have you got the heart is normally the way that we orientate it.

A glide sign's gonna move, on our, on our ultrasound image in a sort of transverse direction. Whereas the heart muscle generally sort of does a bit of a Mexican wave and will move away from you. And then This is again another image you have to be really careful of.

This is an image taken probably quite a long way forwards, maybe a little bit higher up than some of the other images that I've shown you, and again, really easy to look at this and think that you've got. Again, quite a big area of consolidated lung, but in fact this is right ventricular free wall, and these are in fact the coronary vessels that are supplying blood to to that heart. And I think when people start doing lots of floral ultrasound, you can get really excited, particularly when you find something.

But being really careful not to overinterpret. You know, there's several studies that have shown you need actually quite. Large, areas of, of lung to be impacted, to have, to have, to, to have an impact on, on growth rates and performance in the, in the future.

Again, this is another one of those images where The lesion we've got is moderate, probably maybe 2 centimetres by 1.5 centimetres, something like that. Really important you don't include the apex of the heart and the blood sitting within that left ventricle.

And then we can go the other way where you think that you've got really normal lungs and in fact you're imaging the rib. And again, the key thing with rib is a, it shouldn't move assuming that your patient's still, which it isn't always, I'll grant you. But also you don't see those sort of two parallel lines side by side.

And again, in this case, the rib is sitting much nearer the skin, as you would expect, but this animal does have some consolidated lung, and we might be able to miss that if we were scanning rib rather than scanning plural surface. And then don't underestimate, particularly in cards, you know, if you have gone to look at a, a calf or a group of cards that aren't doing very well, you can get images like that in late pregnancy mode with your with your ESA scan. Obviously in adult carers you'll only see the right side of the heart on the right, but, when we're imaging.

When we're imaging cars, we can often see a lot more. And you know, particularly if you're dealing with mycoplasmas where you might be worried you've got pericarditis, myocarditis, and that the ill thrift, isn't just matched by their, pulmonary signs, then you can at least look at the heart and say, We know we can see that this, this heart is not normal, I might add, but you can see that this heart is beating really well. Animals with myocarditis often have very poor fractional shortening, and that there's no fluid in that pericardial, in that pericardial sac.

And then this is a heart. This was taken from, from a calf that was in a barn with a bunch of other coughing calves, had been moved down, an age group, had had multiple treatments. And when you look at this heart, it's pretty round there.

The right side of its heart is absolutely huge and, in fact, it had got a, a defect. This, tricuspid valve was dysplastic and was, was poorly functioning and the calf was in fact in, right, it was going into right-sided heart failure. And then to finish off, no, no talk on bovine plural ultrasound in the UK would be, complete without showing some images of, TB in adult cows, particularly the area of the world that I, I practise in.

And you can see you'll often get these nodules. And they're often quite small. These are about between 0.5 centimetre and 1 centimetre in diameter.

And you can see them on the pleural surface, but obviously they'll be, they'll be throughout the whole, whole of the lung. But this was, this was taken cor eventually, but we could see these, these lesions, cored dorsally as well. And on that, I hope that was interesting and a, At least a starter for some people and perhaps a little bit more knowledge for others who are scanning calves, for, for varieties of reasons as part of their, calf health programmes, but just making sure that, you know, you really are looking for clinically significant lesions, but also making sure that your lesions match your clinical picture.

Thank you very much for your attention and I hope to join you in a webinar soon.