So without further ado, let me introduce Mike Hertage for those of you that don't know him. Mike graduated from the Liverpool University and he's currently the professor of small animal medicine at the University of Cambridge and a fellow of Saint Edmund's College, Cambridge. He's the dean of Cambridge Veterinary School and is in charge of the small animal medicine and diagnostic imaging services at Queen's Veterinary Hospital.

His clinical responsibilities include all aspects of small animal medicine and diagnostic imaging, but he has a particular interest in endocrine and metabolic disorders. Mike was awarded various British Small Animal Veterinary Association awards, like the Woodrow Award in 1986 for outstanding contributions in the field of small animal veterinary medicine, as well as the Blaine Award for outstanding contributions to the advancement of small animal medicine in 2000. Mike has been president of the British Veterinary Radiy Association, President of the British Small Animal Veterinary Association, President of the European Society of Veterinary Internal Medicine, and the President of the European Board of Veterinary specialisation.

He's a diplomat of both the European College of Veterinary Internal Medicine and of the European College of Veterinary Diagnostic Imaging. And recently, President of the European College of Veterinary Internal Medicine. Mike has spoken at many international meetings and has published over 200 articles in referee journals.

And as I said, he's one of my favourite speakers. Mike, welcome back to the webinar vet. Over to you.

Thank you, Bruce. Thank you for that very nice introduction. And welcome everyone.

I hope you have a sort of nice sunny, wintry morning that we have in Cambridge at the moment. I'm going to present a number of cases to you today, in two parts, and we'll start off with the first case, which is a border collie, 4 month old male called Alfie. And Alfie had a history of being lethargic and depressed for about a week.

He was anorexic for most of this period. On clinical examination, he had a pyrexia of 41.2 °C.

He had a very stiff, stilted gait, a low head carriage, and a reluctance to stand. The thought was that either he had a problem in his neck or in his limbs because of the stiffness of gait, and so a lateral radiograph of his neck was taken, and you can see that here. I'll give you a few moments to look at that radiograph.

Then, to move to the distal radius and ulna, we, we tend to radiograph the distal rad ulnar growth plates in young dogs because those are the fastest growing. Growth plates in the body and therefore if there's any problem with growth, it is likely that they will show up in the carpal view. So we've got the right and left craniocaudal view of the carpus and manus there.

And the other growth plate that is fairly fast growing is the distal tibia and fibula, and so we have a cranial caudal view of the distal tibia and fibula and pus there. So take a little bit of time to look at those, we'll go back through them. The whole question is, has this dog got cervical discospodylitis?

Is there congenital hypothyroidism? Is there metaphyscial osteopathy? Is there rickets, or is there evidence of nutritional secondary hyperparathyroidism?

I can't go back, so you'll have to remember what you've seen once the poll question goes up. But do vote. It doesn't matter whether you get it wrong.

There's no marks for that. But if you're committed to an answer, then you're likely to learn more than if you go through the answer that I give and you say, well, yeah, I think I'd do that anyway. OK, so, the majority of people, 51%, think that it's metaphys or osteopathy.

A few people thought of discospodylitis, very few people thought of, secondary nutritional hyperparathyroidism, congenital hyper hyperthyroidism, or rickets. So let's close that and have a look at the films again, if I can go on to the next slide. So this is the lateral radiograph of the neck.

Now with disco spondylitis, what we see is an erosion of the end plates, because the infection starts within the disc space. So the reaction is in the end plates, and you can't identify any reaction in. Those end plates.

It then extends ventrally and you get inflammatory bone, so that irregular new bone developing at the spondars, the metafacial end plates of the vertebral bodies, trying to bridge across and wall off that infection. So you can't see any evidence of that. You can see, of course, the growth plates, but this is a 4 month old dog and these growth plates wouldn't normally close till about 5 or 6 months of age, and so those appear regular and fairly normal.

Then if we look at the distal for legs, I think the first thing you notice is that there is some angulation of the right manner compared to the radius and ulnar, and this could be due to a growth disturbance, the most common growth disturbance is an early closure of the distal epiphysis or growth. The plate of the ulnar shortening this side of the joint, overgrowing on the medial aspect and therefore a lateral deviation of the manners. Now it is important that these are positioned properly to get those views and that interpretation because it is quite easy.

There's quite a lot of laxity, particularly in young dogs, of the carpus. And so if you haven't positioned it, if you put tension on it, you can get some form of angulation. But there is some soft tissue swelling on this side, which would suggest that there is the start of a growth disturbance occurring at that distal ulnar.

Then if we look at the growth plate, the growth plate should be a nice, clear, well defined line, conical in the ulnar but straight across in the radius apart from this slight curvature on the. Yeah, on the lateral aspect, which is normal. But if you look closely, there's also a lucent line that is more or less parallel to the growth plate, but slightly above the growth plate.

And this is typical of metaphycial osteopathy. What happens in metaphycial osteopathy is that the primary bone is laid down on the dhocial side of the growth plate. It grows, but then loses its blood supply, there's haemorrhage, and there's necrosis of those trabeculae, and there's collapse and that's obviously what causes the pain and discomfort that is associated with this condition.

It's usually bilaterally symmetric, you can see the changes, they may be slightly different in each in each limb, but there'll be significant pain over palpation of those metaharcele regions. In the distal tibia and fibula, you've got similar lesions. Here you can see the lucent line separated from the very smooth epiphyseal line here just above it.

Again, the similar changes slightly more difficult to identify perhaps in this position than in the distal radius of ulna, which is why we usually centre on that. At the beginning. So this dog has metasy osteopathy.

Now, what about metaphyscial osteomyelitis? We've certainly seen hematogenous spread to the metaphysis causing very similar lesions to those of metapole osteopathy. However, they tend to be a little bit more aggressive and they're not as bilaterally symmetric as they are with metapocele osteopathy.

Also, there's a much bigger rise in white cell count and and usually blood cultures will help you differentiate that. It is a rare condition, but it's something that you should always consider when you see that necrosis in the metaphyscile region. There is also the evidence of premature closure of the right distal ulnar growth plate, and that requires very close monitoring because if it continues to cause carpal valgus, then some corrective Surgery might be required at an early stage so that the growth can be straightened and then the animal won't have to have more elaborate surgery later on for for that treatment with osteectomies.

So just another case with metaphycele osteopathy, again, you can see the growth plate quite clearly here in the distal radius and all the growth plates. You can see the sclerosis occurring around the area. Of necrosis of the trabecules, so that lucent line that is parallel to the growth plate in both the dorsoventral and lateral projections and usually bilaterally symmetric.

One thing I would just point out, this sort of irregularity of the metapocele area is quite common in fast growing dogs. It's called the cutback zone, and it's a way of nature remodelling the rather wider metaphysis down to the rather thinner, more compact bone that you see in the diapocile area. The same dog, looking at the distal tibia and fibula, again, you can see this area of necrosis, quite a lot of necrosis here.

This is quite abnormal and again parallel to the growth plate that you can identify on that radiograph. And again, similar changes on the left and, and most of the pathology and swelling is around those distal growth plates. OK, case 2.

Case 2 is a collie cross 1 year old male called Bono, and Bono has a left for leg lameness for about 3 months. This started when Bono had been jumping around. He's a very active dog, and he was jumping around, then went fairly acutely lame.

What is noticed about this Lameness is that it improves with the rest. That then recurs after about 5 minutes of lead exercise. The left foreleg lameness was apparent.

There was muscle wasting around the left shoulder. And there was pain on extension and flexion of the left shoulder. Now since movement of the shoulder also can move the elbow, it was decided that radiographs should be taken of the shoulder and the elbow.

So here we have a cranial caudal view of the left shoulder, a lateral view of the left shoulder. Which does look quite a nice radiograph until you realise that actually the area of the humeral head that you might want to look at in detail is overlying the sternum. So it it is quite important to get the positioning.

Right for a lateral view to move it away from the sternum, as you can see here, and move it over if you can either on the soft tissues or if you're really skilled, you can get it over the trachea with the airfield trachea behind it. The elbow, here we have the left elbow, we've got the craniocaudal view and a flexed lateral view of the elbow. And just for comparison, we've got a craniocadal and a fairly neutral view of the right elbow.

So just look at those again, the left elbow, remember it's the left side that the animal is lame on, and it could be a shoulder or elbow lameness. OK, so the whole question here is, what is your diagnosis? Has the animal got bicipitalino sinusitis, osteochondrosis of the humeral head, ununited and canal process, fragmentation of the medial coronoid process of the ulnar, or osteochondrosis of the medial humeral conduct.

So don't be frightened. Think about what you saw. OK, so 47% of you thought that it was osteochondrosis of the humeral humeral head.

Some of you thought that it might be bicycle teno synovitis, and some thought osteochondrosis of the medial humeral condyle were the sort of 2nd and 3rd most likely. Very few of you thought that it was fragmentation of the medial coronoid process, which of course is the most common. Manifestation of elbow, dysplasia, and, very few of you thought that it was an ununited agony or process.

So that's Away from that. We have. So I mentioned the point about trying to get this humeral head away from overlying structures that can mean that you can't see this posterior head very clearly.

. So here we have it moved across, and the impression is that there is some sort of lucency that's fairly consistent. If you go back to the previous ones, that lucency is also seemingly present around here. Now that would be compatible with an osteochondrosis lesion of the humeral head.

Looking at the bicipital tendon groove, this is the bicipital tendon groove. There's no obvious new bone in there. That doesn't mean to say that you haven't got bicepal teno synovitis, but it's certainly not a very chronic change, although the animal's only a year of age.

Now one of the things that also was to look at the elbow. And what we notice about the elbow is that there's no new bone on the anineal process, which is associated with early degenerative joint disease within the elbow, which could be associated with fragmentation of the medial coronoid process. Or associated with osteochondrosis of the medial condyle, and this is where you would see the changes in the medial condyle of the humerus with the regularity of the joint space and sclerosis and the damage to the underlying subchondral bone.

Just the same, that you can't see any changes in the right elbow. Now one of the things about osteochondrosis, if you suspect it is that it is worth taking more than one lateral radiograph of the humeral head and rotating it outwards with lateral rotation, also occasionally rotating it inwardly with medial rotation. And you can see with lateral rotation, this is exactly the same dog, that that area there is now skylined and you can see this flattening and sclerosis of the subchondral bone where the damage to the humeral head has occurred.

What happens in osteochondrosis is that the subchondral bone is not formed normally. There's thickening of the cartilage, and that thickened cartilage loses its blood supply, then fissures and cracks off, and then you get osteochondrotritis desicans when there's a flap formed. Now, one of the ways that you can identify this is to use contrast in the joint.

And if you put contrast into the shoulder joint for an arthrogram, this is the appearance that you get. It not only fills the caudal part of the humeral, joint space, er, the shoulder joint space, but also very often will percolate down around. The bicyclical tendon.

So you can see nice changes around here. There's no evidence of damage, fragmentation, narrowing of the contrast column or obstruction of the contrast column that you might get with bicyclical teno synovitis. But you can see that contrast is percolating under the bone and into the subchondral bone in this caudal quadrant of the humeral head, typical of an osteochondral lesion.

However, some of you may not have considered, ultrasound. Ultrasound is probably really good for shoulder lameness. It's very good for looking at the bicipital tendon and the bicipital tendon, .

The area around the bicipital tendon, the sheath around it, but it's also good at looking at the humerus. So when you look at the humerus, or any bone, you see a very bright, very cleanly defined reflection of ultrasound back from a normal surface. So you get all the The ultrasound is reflected back.

You don't see anything deep to it because the ultrasound's been reflected back. There's very little to pass on. And so you get this very bright ecogenic line at a soft tissue bone interface.

And when that soft tissue bone interface is disrupted, as you've got with osteochondrosis lesion, then you see this irre. Under the cartilage and joint fluid here. So you can identify that very quickly.

This took about 3 minutes to picture that change within the humeral conduct. So it's something worth remembering before you perhaps refer it on for a CT examination, which will be much, much more expensive. So this dog has osteochondrosis of the humeral head, not an uncommon lesion in collies and .

And the like. So our next case is a seven year old entire female Rottweiler called Daphne. And Daphne had a right hind limb lameness for 3 months.

The lameness seemed to be centred on the stifle and a cruciate ligament rupture was suspected. So we've got radiographs involving the distal femur, tibia, and And, and hock so that we can plan any surgery, for a cruise ship ligament. Take a look at those radiographs, look at them in critically.

And then I'll ask you the next question, which is quite a simple question. Are the changes typical of cruise ship disease? Just yes or no?

Oh, we've got a split 50/50. So 50 say yes, 50 say no. I'm not too surprised about that result, because this is a Rottweiler.

They have very straight hind limbs. They commonly get cruise ship ligament disease. And in fact, if we go now back to the radiograph.

Does this really look like cruciate ligament disease? Is there any joint diffusion? Is there any degenerative joint disease around the joint?

Well, maybe not, maybe it's a very acute rupture, but then there should be more joint effusion. And then when we look at the distal femur, is this distal femur normal? Well, you know what orthopaedic surgeons are like.

They decided that this was likely to be a cruciate ligament, so they did a tibial plateau levelling operation, and here's the postoperative result. The dog's still not very sound, quite lame, in fact. Now there is more joint difffusion with some egress into the infrapatella fat pad.

And that's as a result of the surgery. But now look at this distal femur. This distal femur has little loosen holes within the trabecula.

The trabecula have been completely disorganised, and so this looks rather like a very aggressive lesion within the distal femur. So a fine needle aspirate was taken from that distal femur, and that suggested that this was a round cell tumour, most likely a myeloma. It was only found in the one position, so it was a solitary myeloma rather than perhaps the more typical multiple myelomas that you see from time to time.

Now, this is not an uncommon problem and I would just suggest that you know when you Look at something and you think, I know what this is, you know, and I've seen this many times before. Just always look at the radiographs as though you're detached from the case, rather than you're on top of the case. It's got a hind leg la, it's got a stifle laus, most likely to be a cruise ship, and you will see the changes perhaps of a cruise ship on the radiograph and you will miss out.

The other things that are so important. So try and detach yourself from the case and say, I've got this radiograph. What does it tell me about this case?

And you might have come up with that information at an earlier stage. So this is a greyhound, eight year old male neuter called Gucci. He had difficulty in rising.

He had a left hind limb lameness that was worse than the right lameness, although he was slightly lame on the right side. He had really marked muscle wasting of his left hind leg. So it started off with the pelvis and As you might expect for a greyhound, he's got really perfectly formed hips, a nice ball at the end of the femur, fitting in a nice round deep socket within the pelvis.

No evidence of any secondary degenerative joint disease around there, but we can see the muscle wasting on the left hand side, considerable muscle loss in that radiograph. And then we come down to the stifle again, the infrapatella fat pad is not being ingressed very much by joint fluid, but when and no degenerative joint disease around the stifle, but we can. These areas of lucency within the distal radius.

Now that these areas of lucency with a very poor transition from damaged bone to normal bone. It is suggestive of a very active and aggressive lesion, and this was either osteosarcoma, a chondrosarcoma, or fibrosarcoma. Certainly, we would always describe these as primary malignant bone tumours and not try to Identify the histological diagnosis from the radiograph.

Of course, primary malignant bone tumours may have a different type of appearance. They can be very expansile like this one in an Irish wolfhound's distal tibia. Here we've got the aggressive, .

Reactive bone coming out into the surrounding soft tissues with disorganisation of the trabecular pattern within the bone and thinning irregular thinning of the cortex of the bone that interestingly usually allows you some access with a fine needle to get some tissue that can really help with the diagnosis quickly. This case has also got what is called Codman's. The government's triangle is where the periosteum is being lifted up by this aggressive new expansile lesion and then fills in with new bone underneath the periosteum as you will get with any periosteal damage, just filling in with normal new bone, giving you this triangular appearance before you get into the malignancy that you see around there.

If you want to see what a cruciate looks like, this is a good example. This is the left leg, which is unaffected, so we can see the infra patella flat pad, this triangle of fat opacity just underneath the straight patellar ligament. There may be some soft tissue within the actual joint associated with the menisci, and perhaps a small amount of fluid.

But when you look. Caudally, the fascial planes are very straight up towards the abella. There's no evidence of joint fusion within the joint pushing the joint capsule caudally into this area.

And then no new bone and the new bone usually starts on the proximal femoral condyles on the patella, on the abella, and sometimes on the tibial plateau. So if we look at it the effect. Joint, we can see that the infrapatella fat pad is being encroached on by soft tissue opacity that is coming well forwards of the menisci.

Cordially, there is. Movement of the fascial planes, cordially. They're not running straight up towards the paellae, so this has a large amount of joint effusion within the joint, and then the new bone around the proximal femoral.

Or condyles, the distal and proximal ends of the patella around the belly, and some irregularity on the tibial plateau. The typical changes that we would see on a regular basis with cruciate ligament disease. Case 4 is a beagle.

This beagle is 11 years old, a male called Emerald, and Emerald has a 3-month history of hind limb ataxia, a 10 day history of non-ambulatory paraparesis, so progressive neurological signs affecting the hind legs. So a lateral radiograph was taken of the thoracol lumbar and lumbar spine. Thought to be the level of where the neurological localization will go.

I ask you to look at that for a few moments. And then I shall ask you a question. And the question is, is this invertebral disc disease or is there evidence of intervertebral disc disease?

Is there lumbar disco spondylitis, a primary malignant bone tumour, or secondary metastasis from a prostatic carcinoma? Right, so 34% thought it was a primary malignant bone tumour. That's the correct answer.

28% said there was evidence of intervertebral disc disease, and that is not incorrect. Lumbar discospodylitis, 23%, and secondary metastasis from a prostatic tumour, 15%. So, let's have a look at the radiographs.

So I think the most obvious change that you can see as you move down along the lumbar spine. Is the change in formation of the second lumbar vertebral body and moving up the arch to the dorsal arch. So you can see normal trabecular bone here, here, here, and then here you can see that it's disrupted.

You can't make out the ventral border of the . Vertebral column or spinal canal. This extension laterally, overlying this area.

The dorsal arch itself looks as though it's pretty unaffected, as indeed to the zygopothesis, and the disc space. Now what about disc disease? So this is a probably major lesion.

If we follow down the disc spaces, they're all nicely clear. There's no evidence of collapse of the disc space until you get to here at T11, T12, there's a collapse of the disc space and some ventral spondylitis. So the collapse of the disc space is certainly evidence that is compatible with intervertebral disc disease and indeed this dog probably did have disc disease at that site, but probably some time ago, because this looks a more aggressive lesion confined within that vertebra makes a primary.

Bone tumour most likely infection would tend to extend outwards and affect the surrounding tissues, and you can see that the sub lumbar muscles aren't bowing out here. There's probably some ventral new bone along there, but there's no extension onto either the first or the 3rd lumbar vertebral bodies. What about prostatic tumours?

They certainly do cause new bone, ventral to the lumbar spine. There may be some mineralization within the prostate that is fairly irregular, not conforming to the shape of the prostate necessarily, and then you get periosteal new bone, very aggressively extending along the lumbar spine. It usually starts around the lumbar.

Sacral junction. It may extend back along the sacrum and sometimes on the inside of the pelvis. Certainly a very painful condition when you have those bony secondaries from a prostatic tumour, but this doesn't look anything like that.

Now the fact is that we have this tumour affecting the L2. The question is why is the animal suffering so badly, and we can see that using MRI. So this is what is a T1 weighted image with gadolinium contrast so we can identify the tissues more clearly.

Here's Spinal cord, and you can see that around the spinal cord, there should be normally fat and fluid, but here we have soft tissue extending into the spinal canal. You can see that at the same level also on the T2 weighted image. It's just that you can't quite make out the cord so well because the cord has Increased intensity associated with damage to the cord by the pressure of this tumour extending into the spinal canal.

So that damage within the bone is extending into the spinal canal, causing compression to the cord and therefore the clinical signs that the animal presented with. So a vertebral tumour, an osteosarcoma in that particular case. Case 5, is a German Shepherd dog, 4 year old female called Roxy.

And Roxy was being worked up for fever of unknown origin, a head tilt and nasal discharge, but on clinical examination, there was now the appearance of pain over the thorac a lumbar junction. So radiographs were taken of the thoracca lumbar junction here of the lumbar spine, looking down along the lumbar spine. Everything seems reasonably normal, perhaps a little bit of irregularity here and here, which we might appreciate more in hindsight.

But when we move up along the thoracolumbar spine, we see that there's an area here where the vertebral end plates are not as clearly defined as they are on the either side of that. Now that's a very subtle lesion, and you might not make a diagnosis necessarily from that, although there is some evidence of new bone extending from the vertebral M plates of T 9 to 10. But when we do the MRI and this shows you the additional information you could get from an MRI.

Here's a normal disc space, and here's the one that we're looking at at 9:10. You can see that the contrast is going into the surrounding bone. There's some edoema in the bone, this less intense ring around it.

This is an active area of disco spondylitis. The T2 weighted image, we get a similar change, hyper intense change around there extending into the vertebral end plates and into the bodies of those vertebrae. Now this turned out to be a fungal discos spondylitis.

The fungal disease was also affecting the nose, hence the nasal discharge. And also the brain. The dog was treated with itraconazole and actually made a fairly good recovery, but, German shepherds have a different type of immune system to most other dogs and.

Perhaps more prone to fungal infections than other breeds of dogs. We've seen it on a number of occasions, and two years after this bout had been resolved completely dog off all treatment, it then represented with a much more disseminated fungal infection and unfortunately it had to be put down. So just remember about fungal disease, not common in the UK, but it does occur, particularly occurs in immunosuppressed or immunodeficient animals.

K6 is a Scottish fold, 11 month old male neuter called Goose. Goose had a right for limb lameness for two months. He lives completely indoors.

The incident appeared to occur when he jumped off the hob, but actually when the owner was pressed on that, they think that the lameness was actually present before that particular incident. So here we have the radiographs of the distal forelimb. Again, we choose that because they're fast growing areas of new bone.

Rather sadly, of course, this is right foreleg leanness, probably best, therefore, not to put the catheter into the affected limb, but that's what happened on this particular occasion. Here we have the left limb. Craniocaudal and lateral.

The right limb, lateral. And a close up of the right and left limb is lateral. So hopefully, you can make out that there are some changes.

Those changes really are in the epiphysis. They're irregular. The carpal bones haven't developed normally.

There's new bone around the accessory carpal bone, the distal radial epiphysis is not the normal rectangle that it would normally be. So there are obvious changes that have occurred in this dog, in this case. Sorry, and this is ostochondrial dysplasia of the Scottish fold, and it's a dominant gene variant.

The gene variant is associated with the the cartilage defect within the pinna, but also in association with this development of bone in the osteochondral dysplasia. And as the animal gets older, this is an older animal with the disease, you can see that there is marked degenerative change around those joints because of that osteochondral dysplasia. The final case before we take a break is a domestic shorthair cat, 16 years old, a male neuter called Oscar.

Oscar has marked weakness and lameness, which has been progressing over a 4 month period. He's now hyperexic, suffers from weight loss and hypersalivation. He's been diagnosed with hyperthyroidism, but it's fairly poorly controlled, and he's iris stage 2, chronic kidney disease.

So here's the madness. And as we look around the manus, it looks as though the carpal bones look fairly well defined, coming down the metacarpals, things look normal. When we come to the distal phalanx, then we can see that there.

Changes within the distal digits of the phalanges, a lot of soft tissue swelling, loss of new bone, loss of the nail bed on this third phalanx here. No, not so much changes, but some changes within the nail of the second. On the left side again, similar lesions in the third digit with loss of new bone of P2, P3 in the nail bed in this soft tissue swelling.

Right back to the joint between P1 and P2, damage to and loss of the P2 and P3 in the 4th, and some changes within the nail bed of 2 and 5 with that lucency around there. In the hind leg, we've got similar changes, so we've got soft tissue swelling around the digits, particularly of again, digit 3, or digit 4 here, loss of the bone, damage to the bone and the resorption of the bone, damage to the nails and obviously malformation of those nail beds. So then we moved on to doing chest radiographs, right and left lateral, which show a lesion, most clearly seen on the right side, which would suggest that it's probably in the left caudal lung field, less obvious on The left side because that's the downmost lung, so there's less air around the mass.

Here we can see it now in the caudal left lung field associated with the distal bronchus. So for those of you who haven't seen this condition before, this is feline lung digit syndrome. There is a primary pulmonary neoplasm.

In this case, most likely a bronchogenic carcinoma, and the lesions within the feet, which are clinically the most obvious reason for the lameness in this case is, multiple digital metastases. So I'm happy to answer any questions on any of those cases. We'll then take a short break, but happy to answer any questions that you might have.

Mike, thank you for that and I'm sorry you're battling with your throat there. We won't have too many questions and then you can go and lubricate that a little bit, but fascinating, fascinating cases really. Couple of varied questions.

In the case when you were talking about the OCD in the shoulder, and you were using contrast, would you routinely use contrast or would you accept your radiological diagnosis based on that, especially that lateral, twist of the one was a beautiful view. Yeah, so, so it, I think the answer to the question is no, we wouldn't routinely do. A contrast examination of the shoulder if we've made a diagnosis and confirmed it from the plane radiographs.

It's an intervention that probably in this case hasn't added much since there was the question mark over the bicipital tendon. It did add a little bit more information to show that that was normal, but no, we wouldn't normally do that. Excellent, thank you.

In the, cruciate section that you were talking about, the changes that you showed very clearly, obviously are, are great when it's a chronic case, but when it's a more acute case, at what point would you expect to see the sort of fluid changes and then at what point would the bony changes come in? So the fluid changes will occur within 24 hours of of of a partial complete cruise ship rupture. So if an animal's running across a field, puts its foot down a rabbit hole, and comes back late, you would find, joint effusion, within 24 hours of of that occurring.

The degenerative changes take a little bit longer, of course, but most cruise ship changes in a more sort of chronic. There's slow stretching of the cruciate ligament, so there'll be some joint. Diffusion, but also some laxity of the joint, which will give rise to new bone formation.

So the new bone actually is nearly always there in animals that have been lame for, say, 4 weeks or more. OK. Yeah.

Yeah, fits in with the, the whole physiological process, as you say. . Talking of cruises, going back to the Roy case that you had, would you in that case have suggested rather taking the approach of, of doing a, maybe a fine needle aspirator or a bone biopsy or something like that before the cruciate surgery or even at the time of surgery?

I, I, I, I think that that, you know, I think that would have been ideal. I mean, I'm not sure that there was a significant change really to Justify an early cruise ship surgery, so I, I think that you know, had. People looked at the radiographs a little bit more critically at that point and said, you know, really this doesn't quite look like a cruise ship, even though it's lame in its in its stifle, then maybe we should think about this, you know, in a little bit more detail before doing the surgery.

But having done the surgery, taking the bone core biopsy at the time of surgery would have been, you know, quite an acceptable way of doing it. You know, some cases of cruise ships don't always show up that well on air graphs and therefore, there's a clinical imperative to Try and help the animal and, and, you know, satisfy the owner. So, so, you know, the cruise ship surgery may, may, may be done, but if you've got a doubt as to whether this is the correct way to move forwards, then you should make sure that you've explored every other opportunity of making a diagnosis.

Yeah, and, and those bony changes that were seen on the radiograph, if you had said, look, let's, I know it's possibly a cruciate, you don't want to wait too long. We've got a bit of time on cruciate surgeries. Would a week or two have made a difference to to taking more?

Yeah, well, the, the, the, the distance between the two was 6 weeks. It was a 6 week follow up that I showed you the radiograph and you could see the, the change in the new bone, the, the, the distal femur at that stage, so. At that time, obviously, the the the diagnosis kind of moves a little bit towards that distal femur as being the major cause of the problem and so, you know, a bone biopsy then or a finally as of the bone would have given rise to that diagnosis.

So yeah, yeah, you, you know, you, you could wait and and and I'm not criticising the orthopaedic surgeon for having done the surgery, they felt that that was the. The clinical presentation and you know trying to help me out and hindsight is great, isn't it? Last question for you, Mike, before we let you go and throat out of bones and that, would you use a needle or can you use other needles or any needle for that fact?

So if you're not Or not used to using it or you don't have any MCD needle, then a very stiff hypodermic needle will often find a traced into the bone of these diseased dogs. Although they, you know, got an explosive lesion, they're often quite soft. And so you can get the needle into the, bone and, and suck out, contents from the bone and make a diagnosis that way.

The younghidi has the advantage that you can look at the histological pattern, rather than just look at the cytology of the cell, which can be very helpful, particularly for bone pathology. Fantastic. Mike, as always, that was brilliant.

Folks, we are gonna take a bit of a comfort break now. And, we said in the beginning about 5 minutes. So if, on my clock we've gone 10:57, so if we can be back at 1 or 2 minutes past 11, and Mike will be ready to once again a us with his fantastic presentation.

So 5 minute comfort break. Thank you everybody and we'll see you back then. Good morning and welcome back to part two of the diagnostic imaging session on this day 6 of our virtual congress 2022.

For those of you that have just joined us, we are asking you please to pop your Q&A's or your questions into the Q&A box, and we will get to as many of those at the end of this as what we can. Also, just a reminder, if you have missed what has been a fantastic session so far, these are being recorded and they will be available on the website. So just keep an eye on that.

Mike, welcome back. Hi. I hopefully my voice will, will, will last the whole duration of this.

Oh blessed. Well, I, the, the content is just as riveting as it always is. So over to you.

OK. So welcome back, everyone, and welcome to new people that have joined for this presentation. We're going to move now more towards the thorax because people find that perhaps a little bit more challenging than perhaps bones, and certainly the group that we're here for the first session were very good on the bone side of things.

So first case is a Rhodesian rich back 12-year-old male called Bonham. And Bonham had a previous history of a gastric dilation of vulvulus, treated surgically with gastroprexy and splenectomy 4 years previously. Also a previous history of eosinophilic enteritis diagnosed and treated with diet and prednisolone.

But recently, he'd suffered from onset of coughing and wretching, is now rather subdued and inappetent. And so the first stage was to take some thoracic radiographs. After looking at the clinical examination, I should say, obviously you should do a clinical examination before you do your radiographs.

He Bonham was bright, alert and responsive, and a pulse rate of 80 beats per minute. Thoracic auscultation and percussion were unremarkable. So here are the radiographs.

This is a right lateral view of the thorax. Just going to show you a right lateral and left lateral. The right lateral is a right lateral because the ru of the diaphragm are parallel.

In a right lateral view, then the right cross of the diaphragm will move forwards under the weight of the abdominal contents. The right cross. Of the diaphragm has the cranial vena cava coming out of it, so we can trace the cranial vena cava coming out of the right crust of the diaphragm into the heart.

The left crust, which is now more cordially, has of course the gaps within the fundus beneath it. So we can say that that definitively is the right lateral view. And this is the opposite view, the left lateral view, and now the left crust has moved forwards with the air filled funders overlying the caudal lung fields in a two-dimensional view of the three dimensional structure.

The coralbina cava now extends back across into the right crust which you can see coming up here. So we can see this division rather than having two parallel lines as we had in the or nearly parallel lines as we had in the right lateral, we've now got this V-shaped appearance of the er, the left crura being cranial to the right ru. Makes a slight difference also to the heart.

The heart tends to rotate a little bit more in the left lateral view, so we normally take the right lateral view for looking at the heart because it's in a more constant position and the left lateral allows the heart to move around. So, The question here is, you've all seen the nodule, hopefully, is it in the left cranial lung lobe, the right cranial lung lobe, or the cranial mediastinum, or is it outside the thoracic cavity? Right, 40% said it's in the left cranial lung lobe.

22% in the right cranial lung lobe, 32% in the cranial mediastinum, and 6% said that it was outside the thoracic cavity. So the left lung lobe, left cranial lung lobe gets the majority. Although it's not by any ways unanimous, so, well, it is in the left cranial lung globe where we could have taken a dorsoventral obviously to show that, and we normally take the dorsoventral because the the heart and lungs are in a very constant.

Position for that. We turn the animal on its back, and then we may get slightly more view of the lungs, but there's always the risk that if there's any fluid in the chest, that, that will be redistributed and could cause problems. So our standard is a left to right lateral, a left and right lateral and a dorsoral, and that shows the mass within the left cranial lung lobe.

Now, could it have been within the within the mediastinum? Well, there's no evidence that the lung lobes are moved around the mass. They seem to be completely within the mass.

The reason that it's in the right, in the left cranial lung lobe rather than the right is because when you add a lion animal on its side, this lower lung lobe will deflate and there's less air around the mass. So if it's in this side, it will be less clear, whereas on the opposite side, on the left side, there will be more air within the lungs, and this will. Accentuate the border of the mass.

So in the right lateral, showing the left cranial lung lobe, we get a nice view of the mass, whereas when we put it into left lateral cubies, so the air is squeezed out of the left side, we can't make out the mass as clearly. And again, we can see that there's no movement of the lung lobes around the cranium mediastinum. If it's in the cranium mestinum, the lung lobes can't extend past it and it wouldn't show up ventral to the mass.

If it's outside the chest, there will always be air around it and it will look very opaque on both left and right lateral views, but of course should be picked up by clinical examination. So just to show the difference in sensitivity of X-rays versus CT. CT is great for looking at the thorax because of the air-filled lung, but also because it's a it's a cross-sectional imaging technique that allows us to look at slices of the body rather than compressing the whole body into a two-dimensional representation of a three dimensional structure.

So I've just taken a few slices out of the CT. We can see the mass, of course, that's very obvious, but we can also see that there's a mass in the contralateral side on the right side dorsally, which we hadn't appreciated on the radiographs. Another one more cordially on the left side and a further one on the right side.

So this has a number of secondary metastasis from the primary lung tumour. It was a primary lung tumour with secondary metastasis, and that makes the surgical treatment of this condition very much more complex. Because, obviously the secondary metastasis will grow even if the primary is removed, where if the primary is the only tumour, then removing that has a fairly good long, lasting action on the patient.

The second case I want to show is an Italian Sinoni, 2 year old female called Bracken. Bracken had a 2-week history of acute onset hemoptysis, so bringing up blood stained fluid. This was progressive over the two week period and Bracken was now dull, depressed, and inappetent.

There was dried blood around her nostrils. She had tachy mucous membranes, tachycardia, increased respiratory effort, and increased lung sounds and crackles, especially in the right middle lung fields. So here's the left lateral view of the er er thorax of Bracken.

This obviously shows the right side better, which is where some of the pathology was thought to be present. And here's the dorsoventral view, showing that the pathology is certainly more severe on the right side. So, what is your diagnosis?

Has this dog got pleural effusion? Is there a primary lung tumour, a lung load torsion, or is there diffuse lung pathology with consolidation? OK, so the majority of you felt there was diffuse lung pathology with consolidation, which is the correct answer.

22% thought there might be a lung load torsion. Lung load torsion is always difficult to diagnose. With radiographs, or can be, and certainly something you should always, consider, in cases where there's displacement of the bronchi.

Primary lung tumour, 11% and pleural fusion 13%. So. Let's have a look at those radiographs again and see what we can identify from them.

So here's the left lateral view and there's no doubt at all that there's consolidation of lung tissue. You can see an air bronchogram coming down, the branching air bronchograms from that bronchus. The bronchus is .

Probably, here, either the middle lung lobe that's extended or maybe the cranial lung lobe that's displaced down, but it's not really displaced in the way that you would have a lung lobe torsion that goes through 90 degrees or even 180 degrees, so it will be completely displaced by that change. But look at the rest of the lung, and those of you who made the diagnosis that this had diffuse lung pathology are absolutely right. There's marked bronchial and interstitial markings within this caudal lung field area, extending down ventrally, so there's some air bronchograms developing ventrally down here, the changes in the cranial lung lobe over here.

As well as that consolidated right middle lung load that we could see on the dorsoventral radiograph again with air bronchograms going through. Now one of the signs of a lung lobe torsion is when we have consolidation of the lobe and displacement of the lobe, but we also have a vesicular pattern. And the vesicular pattern is small groups of air pockets, very small air pockets grouped together, giving it a sort of very fine bubbly appearance.

And if you see that, you should be concerned that there might be a lung load torsion. Is there pleural fluid? I don't think there's a lot of pleural fluid.

There might be just a little bit of a fissure line around here, maybe a little bit of retraction away here. There's certainly not a marked amount of pleural fusion, and probably not a lot more than would normally be present within the thorax. Pleural effusions usually taps the lung lobes equally on both sides.

Certainly, even if it's a unilateral, fluid accumulation, all the lung lobes on the affected side will be collapsed to a similar degree and will still remain air filled, so that doesn't look likely. So on ultrasound, there's no doubt that this right middle lung lobe is very consolidated. If you look at the lung tissue with ultrasound, the air will reflect back all the ultrasound and so you don't see anything deep to that reflection.

All you can appreciate is that there is movement with respiration, the so-called glide sign of the lung lobes moving against the chest wall. But if you put the probe on this animal and you can see into the lung, you know that this lung is now no longer air filled. As you move around, you might find some areas where there seems to be a drop out of the information.

And that could be because there's air within the broners, it could be that there's . Other changes within the pathology that is causing that drop out as well. And then in this area, we saw what looked like a sort of more mass-like lesion with some sparkly hyperchoic areas.

These are in real life, little air bubbles that have moved into the. Tissue, not enough to reflect all the ultrasound back, but enough to reduce the inflammation, distant to it, but also to come up as these bright sparkles. So there seems to be some mass-like lesions within that area.

Well, the surgeon was convinced that there might be a lung lobe torsion, so it went in, and this is the lung lobe that was affected with the consolidation. You can see that it's markedly abnormal and consolidated, and that was removed, leaving the more normal air filled lung, the pinker areas of normal lung to expand into that area. Well, this is the histology of that lung showing that.

There are eosinophilic granulomas filling up that lung lobe. And when we know that they're earsinophilic granulomas here, it makes sense that the caudal lung lobes and the cranial lung lobes were also affected by osinophilic bronchoneumopathy or pulmonary infiltrate with eosinophils. And in these instances, the earsinophils can either affect the bronchi, can affect the interstitial tissue, or the alveolar tissue.

So you could get eosinophilic bronchitis, eosinophilic pneumonia, and osinophilic bronchopneumonia, and the worst form. Of all is the granulomatous form, that is the one that is least likely to respond to treatment. There's a variable severity of the clinical signs in these cases, coughing is usually the primary complaint associated also with tach, dyspnea, weight loss, depression, anorexia can occur as well.

A more typical case would be this young dog here, often of large breeds, so husky types of animals, perhaps more commonly affected, and a marked bronchial interstitial pattern. You can see these bronchias tram lines going out towards the periphery. The background opacity is no longer as black as you would normally expect, so there's an interstitial pattern there.

That would be a fairly typical florid involvement with pulmonary infiltrate with osinophils or earsinophilic bronchoneumopathy. And again, it's usually bilateral. One side might be slightly worse than another, as you can see on this dorsoventral area, but this is all from the same dog, a two year old husky, as I mentioned before.

On bronchoscopy, you can often see this yellow, very tenacious. Muopurulent discharge that comes down slightly greenish on on occasions, and if you take that material and look at that cytologically, then it comes back with large numbers of eosinophils compared with other. Cells and this is an aspir from a dog with a bronchialvelava from a dog with a sinophilic bronchneumopathy, and you could see the number of earsinophils with these earsinophilic granules within the cytoplasm all over a few macrophages from the alveoli and .

Other goblet cells occasionally, but, mostly eosinophils. Now the standard cases which have a broncho interstitial pattern will usually respond very positively to prednisolar. Usually at 1 milligramme per kilogramme twice daily, and then repeating the radiographs until the changes have disappeared and then reducing the dose to the lowest effective dose.

Some may come off treatment, some may require long term treatment, and if they require long term treatment, then a term and day dosing is, is, the, the preferable way of trying to control the disease. So prognosis for control is, is usually good, except for the very severe granulomasous form of the disease as in this case. But having removed that really severely affected lung lobe, the remainder of the lung responded very well to prednisolone.

And it's a question as to whether we could have got that affected lung load to have resolved with steroids if given. At an earlier stage, but we don't have that information because we use that for the diagnosis. OK, a third case is a cavalier King Charles Spaniel, a 1 year old female called Maggie.

And Maggie was presented with a 3-week history of lethargy, coughing, and increased respiratory rate. There was no response to antibiotics or steroids, some weight loss despite a reasonable appetite. So a young dog with a very progressive tachynia and dysne in and no response to antibiotics and steroids.

Clinical examination just showed the increased respiratory rate. There were increased breath sounds over all the lump fields, and so we took these radiographs. So here's a dorsoventral radiograph and we start off with dysneic animals taking a dorsoventral radiograph because we're concerned that there might be free fluid and we don't want to push these animals into a critical state by struggling with them.

And moving them around. If they walked in, they will usually lie there in sternal recumbency without any problem. Once we've got this view, then we will try to position the animal in a different way.

If it's got fluid, then we may take the fluid off before we start positioning it in a different way, so it's no longer at risk of developing respiratory embarrassment. Now we've got the lateral view, and you can see that that's a, a right lateral view. And the question is, What pulmonary pattern predominates?

Is it a bronchial, interstitial, vascular, alveolar, or mixed capacity? So we want the predominant pulmonary pattern, so there should only be one answer. OK, so, the majority went for a mixed pattern.

Then an interstitial pattern with less with an alveolar pattern, followed by a bronchial pattern and, and very few went for a vascular pattern. So let's have a look at the detail in it. Well, firstly, we did take some arterial blood because this dog was struggling, so we supplemented with oxygen.

You can see it's arterial, PO2 is reduced, it's PCO2 is also increased. So it got some oxygen supplementation. There's very little evidence of change on the blood, just a mature neutrophilia, moderate neutrophilia considering the amount of change within the lungs.

Oh, I forgot to show you the radiographs thing, we'll have to go backwards. So what do we see here? Well, we can still see Bronky.

They're not air bronchograms. We can see the bronchi because they have a bronchial wall, so there's some increase in bronchial pattern, but the background opacity is really what is missing. We can't really see any typical lung full of air, which should be black, either in the Yeah, lateral or the dorsoventral.

On the lateral, you can see that the area of thickest lung is the one that has the most opacity, showing that it's really diffused through the whole area of the lung tissue. Again, we can see the. Air within the bronchi, but it's bordered by bronchi with bronchial walls, which we can make out so that is not an air bronchogram.

An air bronchogram is where we lose all the background detail, which is flooded alveoli, so we lose the wall, we lose the vessels, we lose everything around it with fluffy, ill-defined passages with air filled bronchi within the middle. But this is a very fine, if you look very closely, it's a very nodular, fine nodular opacity. This is a miy interstitial nodular or unstructured.

Pattern because in other areas it looks like a sort of a sponge-like appearance with some air pockets that don't really conform to any bronchi, but just appear like a sort of sponge, which is partly because the interstitial tissue is so much more opaque than it should normally be. OK, well, a BAL from this case showed these organisms. These are magenta trophyzoites, the magenta granules within the tropozoites suggest that this is a parasite, pneumocystis carini, .

We don't always get a positive result from a bronchoalvelavage. In some cases, we have to do a fine needle aspirate of the lung to be able to retrieve the lesions, retrieve the cytological diagnosis. Either way, you should be able to get a diagnosis of the pneumocystis organisms.

There are also a few eosinophils, very low numbers of neutrophils and a few macrophages as as well. So this is a diagnosis of pneumocystis carini, which is a yeast like yeast-like fungus previously classified as a protozoan but now moved into the fungal category. It is as with many fungal diseases associated with immunosuppression.

So these young dogs that get pneumocystiscorini in the UK, cavalier King Charles Spaniels and miniature dachshunds have been reported with pneumocystiscorini. It's associated with immune deficiency, particularly of of IgG. IgG is low and the IGM is high, but that doesn't clear the infection, so the lack of IgG is the thing that is the crucial cause of why these animals get pneumocystis carina.

It Occur in older animals as it can in older people that are immunosuppressed for some other reason and therefore prone to secondary infections with with commensal organisms. Now the treatment is with potentiated sulfonamides. Also, the fluoroquinolones has some activity against pneumocystis carini.

As well as the antifungals, so it's a question of getting the right antibiotics, the right antifungal, and then these cases resolve fairly quickly. The dyspne goes within about 4 or 5 days, and then we can see some 4 weeks later that there's good clearing of the lung. We can see the heart much more clearly.

The lungs aren't back to normal and, and maybe they'll never get back to normal because there'll be some fibrosis within the lungs associated with the original inflammation, but certainly the animal is asymptomatic and, and is is clear of the disease at the moment. The next case is a German shorthaired pointer, 4 year old neutered female. And this, German shorthaired pointer had a history of coughing over a three week period.

It was a dry, unproductive cough with noticeable halitosis. I'm going to show you the 3 views of the lung, and then I want you to answer a question as to what the diagnosis might be. This is a right lateral view of the thorax.

This is a left lateral view of the thorax. And this is the dorsoventral view of the thorax. OK, right lateral view.

Left lateral view. Dorsoventral view of the thorax. Question I'd like you to answer is, is this bronchan pneumonia?

Has it got a lung tumour, inhale foreign body or lobar pneumonia? OK, so, pretty evenly split between an inhaled a foreign body and bronchop pneumonia. Lobar pneumonia came next with the lung tumour being lowest on the list.

So let's have a look at the radiographs again in a bit more detail. So this is the right lateral view, remember, looking mostly at the left lung field. We can see an increased opacity within the caudal lung area.

We can also see that there are some changes, some peribronchial infiltration and thickening of the bronchi ventrally in the caudal and perhaps middle lung lobes on. That animal. The close up shows this area, and one of the things where you should perhaps note.

Is that there is only one bronchus. Normally there should be paired bronchi, the left and the right caudal lobe bronchus should be very close to each other. We can only identify one bronchus with air within it in that position.

Now when we look at the dorsoventral, we can see that the affected side is on the right. The left side we can see the bronchus coming down here with the artery, lateral to the bronchus, the vein, medial to the bronchus as it passes down into the caudal lung field. And we can see that these areas of lung are much more normal, as well as these areas of lung than this caudal lung field on the right.

So if you thought this was bronchopneumonia and it's affecting one lung lobe, you need to have a reason why it's got infection within one lung lobe. Because in animals, the connection between the lung lobes is fairly continuous, so involvement of one lung lobe will usually spread to all of the lung lobes very quickly. And we only get lobar pneumonia in association with a pathology within that affected lobe.

It could be a tumour blocking the bronchus or obstructing the bronchus. It could be a foreign body obstructing the bronchus. So when we look on this side, we can see the trachea coming down here.

We can see it dividing at the carina. Into the cranial lobe bronchus, middle lobe bronchus, the caudal lobe bronchus, then we come down the caudal lobe, main stem bronchus, we can see that we lose it. We cannot follow it any further than that, that there's a change that we see within the lung.

It's really centred around that bronchus quite different to the bronchus on the affected side. We look at that in more detail again, we can identify that the bronchus appears to be obstructed with something in the caudal lobe on the right hand side. Now this seems to be a little bit beyond where the accessory lung lobe bronchus would come off, that would come off soon after the bifurcation about here, so the Accessory loan doesn't seem to be too involved in the process of the obstruction.

It was an inhaled foreign body. Just show you a number of other cases just to hone that into you that if you get lobar pneumonia affecting one lobe, then you should always think of an inhaled foreign body or a tumour within that lung area. This dog had a 6 to 8 week history of a soft, moist cough.

Often, of course, these coughs will start after the animal's been exercising in a field, because the most common foreign body inhaled is a whole ear of wheat or barley. It's non-responsive to antibiotics and fenbendazole, no impact on exercise tolerance, because it doesn't take up a lot of lung pathology, it just affects that one lung lobe. It's worse in the morning, or after the animal has been lying down as the mucus that is retained within that, lung lobe starts to get coughed up.

And halitosis is very common with these tumours. Sometimes the breath is absolutely repugnant, and that's what the onus may actually present for. In this case, it was referred for CT with these radiographs.

So here we can see that it's a fairly flat-chested dog. It's a little bit rotated, so it's not perhaps ideal. We can see one bronchus here, maybe a little bit of increased capacity around there.

That becomes much more obvious when we look at the dorsoventral. So we'd be looking at the left caudal lung lobe quite a way. Down actually, because here's the biification.

We can see the broncos open right way down to here. This is where the foreign body is going to be, right side is clear, accessory lobe is clear. And and here's the view from the CT.

So this is the foreign body completely blocking that bronchus. Retaining the secretions with inflammation in the dependent part of the lobe associated with that presence of the foreign body, slightly less aerational so in that. And this is what you see at bronchoscopy, you just see the end of an ear of wheat or barley.

But you've got to make sure that you remove the whole ear of wheat or barley, not just a few of these seedlings around the end. And this is what you should be retrieving. Of course, it goes in forwards and it can't come out because of these ears.

Stopping the migration outwards, a little bit of air can get past it. Seions can accumulate around the head of the wheat or barley, and of course that festers and produces the smell of halitosis. Occasionally you can see the actual foreign body, in this case here, we can see the end of the foreign body, we can see the start of the barbs coming off the side and the loss of the bronchial lumen, in that case.

The next case is an Italian greyhound, 7 years old, female, a 4 week history of coughing, precipitated by excitement or exercise. Occasionally she has coughed up blood when she gets really excited, but only a small amount of blood but still serious complication. She's positive on the tracheal pinch test.

And she has a grade 3 out of 6 systolic murmur. These are the radiographs. So dorsoventral radiograph.

Left lateral radiograph. Right natural radiograph. So look at those radiographs.

I'm going to ask you what radiological signs you could see in those radiographs. Did you identify any of the following nodules, bully consolidated lung lobes? OK, so, 44% said consolidated land loads.

33% said nodules, and 23% said bully. So what is the answer? Well, actually, the answer is that it's got all of those changes.

So if you look at the CT and if I can get this to work, worked just before, will it work again? No, it's not gonna work, so. Interesting.

It always works and then it won't work in the presentation. Anyway, I do have some slices that are taken from that CT. So these are reconstructed slices, these are sagittal slices of the left side and the right side.

So black is going to be air, so you've got some very large bully. Some of these bully have fluid within them, so the dog is in sternal recumbency, so there's a fluid line there. And there's also a fluid line in the left cranial lung lobe bullet.

There's also consolidation of the lung. With a ground glass appearance. Surrounding it and here surrounding that change there.

On the dorsal plane starting ventrally and and working up, we can see some air filled bully here, here and here. But slightly higher up, we've still got this air filled Buller on the right hand side, we've got our consolidation on the left hand side there. We can now see fluid in another bulla dorsally on the right hand side.

And so we've got multiple bully glebs, some of which are fluid-filled. The causes of which could be parasitic, infectious, neoplastic or idiopathic. On a BAL we got E.

Coli that's cultured sensitive for refloxacin, and so the dog was treated initially with enfloxacin for 6 weeks with codeine phosphate to reduce the amount of coffee, because bully and labs, particularly in deep-chested dogs, are common and usually associated with the force of the coughing. So these are 8 months later, and whilst all the changes have disappeared, I think you'd appreciate that they're very much less than we saw on the original radiographs. The large labs and bully have disappeared or seemingly disappeared.

There might be some small bully around here, but those also may just be associated with the fact that we're looking at a three dimensional image in a two dimensional way. But considerably improvement. That was a surprise to me.

I it's a surprise to you as well that you can have that severe lung damage with all those bully and blebs, and yet antibiotics seemingly, and of course nature have resolved those changes and the lungs have gone back to normal. Dog is 100% very fit, active and healthy again. OK, I think this is our last case.

So this is a German Shepherd dog, 4 year old female. Rather poorly grown with a chronic cough. This is the radiograph.

The lateral radiograph. This is the dorsoventral radiograph. And this is a lateral view of the abdomen.

Just going back again, so this is the right lateral view. Do a ventral view. Lale The question I'd like you to answer is, is this a cranium metestinal mass?

Is it a cranial lung lobe mass? Is it a cranial lunglobula? Has the dog got megaesophagus or a vascular ring anomaly?

OK, so the majority of you got the right answer, which is a vascular ring anomaly. Then followed by a cranial mediastinal mass. Followed by megaesophagus.

Followed by cranial lung lobe mass and cranial lunglobula. Let's have a look at the pictures a little bit more detail. So on the lateral view, we can see that there are some changes in the cranial mediastinal area.

We've got this soft tissue band that comes down that we could see on the original radiograph. We can also appreciate from that that there was some Things filling this area that are now no longer present. So that would be likely to be food material.

We can see the cranium mediastinal structures more clearly than normal, although this is not a pneumo mediastinum. We can see the trachea with the dorsal tracheal band, we can see gas here, we can see the cranial vena cava coming in there, and we can see the left subclavian and brachial trunk coming out from the aorta. So what could this be?

There's nothing in the caudal abdomen and the lateral abdomen were unremarkable apart from this mineralization within the liver, which is an incidental finding in an older dog, unaffected, unassociated. With any liver malfunction. We give this dog barium and meat, then we can make our diagnosis.

This does have an enlarged oesophagus. Whether you call it a megaesophagus, it is a megaesophagus, but a typical megaesophagus will be throughout the length of the oesophagus. This then goes to a stretcher.

At the heart base, a very narrow stricture, and then goes into a normal piece of the oesophagus and then into the stomach. So this site here at the heart base would be a typical site of a vascular ring anomaly. And it looks a fairly severe amount of stricture, and the most severe stricture that we see with a vascular rig anomaly would be a ligamentum arteriosum with a right-sided aortic arch.

The right, say the aortic arch gives rise to the ligamentum arteriosum that then compresses the oesophagus as it passes down towards the stomach between the incompressible aorta, the trachea which is incompressible, and the pulmonary artery. So it acts as a band around it. You can have some aberrant subclavian arteries.

That cause strictures, but those strictures are not usually as severe as we could see in this area of study. Of course, if the aorta is on the left hand side, as it should be, then the ligamentum arteriosum between the two does not constrict the oesophagus, which passes by the trachea and and aorta. So there was mild aspiration pneumonia, which is the cause of the chronic cough.

This dog is 4 years of age, it's a congenital problem, a vascular ring anomaly, hence its poor growth. It's got a right aortic arch, which was just about visible from the from the dorsal. View, but in this case, it wasn't just a ligamentum arteriosum, it actually had a patent ductus arteriosis.

It's one of the things you should always bear in mind is that the ligamentum arteriosum may not have closed completely. It may still be allowing a certain amount of blood to pass. Between the aorta and the pulmonary artery that could be picked up with echocardiography if you considered doing that examination, but it's just a word of warning because if you're the surgeon going in and you think that it's an occluded ligamentum arteriosum and you cut it, you will get a little bit of a surprise.

Well, that's all I have for you today. I think we've got about 5 minutes left for questions. I'm very grateful for you attending these 2 sessions.

I hope that you've got something useful from these sessions, and I'm happy to answer any questions that you might have. Mike, thank you so much. That was absolutely fantastic, and I'm sorry that you're battling with your throat.

We, we don't have much longer to get through. You've done fantastically well. Thank you.

I can assure you it's not COVID, not that it can pass down the the internet, but of course, having not had a cold for 2 years, then, you know, these colds tend to be a little bit more severe, I think, as many of you probably found yourselves, since we've had, more, interaction. Yeah, it's been a bit of a strange time, hasn't it? Yeah.

Mike, there's one question that came through. It is related to the test, obviously, but it's from your first session. If I don't mind asking you quickly.

On that feline lung digit syndrome case, the, the heart looked to be, hypertrophied. Possible CK CKD. So, so the, the heart had mild degree of hypertrophy.

There was minimal left atrial enlargement, but the wall was slightly hypertrophied, which was partly because it had raised, blood pressure. And and partly because of course the hyperthyroidism that was poorly controlled, so both of those will have, you know, interacted to, to give some changes were very well spotted the part. Yeah, fantastic.

You and I have done loads of these sessions and whenever we're talking about chest radiography and everything else, this question always comes up, so it's no surprise to you. Your approach to these patients as far as, anaesthesia and sedation and that before radiography when they've got suspected severe lung pathology. Right, well, so I, I think the, it depends on how severe you think the patient is suffering from its lung pathology, and, and that obviously should come out in your, your clinical assessment and clinical examination.

I think if you, you think they're safe to sedate, then that's fine. Anaesthetizing them, of course, is even safer for the patient because then you have control over oxygenation of the lungs. I think the one thing that I would say is that if you consider that there might be pleural fluid, then you should either do a TAS ultrasound scan to check for fluid.

Or get the animal just to lie on the table, even if it's slightly rotated, and get a dorsoventral radiograph and check as to the severity of the lung pathology. But if it's got really severe lung pathology, my view would be that it's better off anaesthetized than it is necessarily sedated, and certainly, you know, sedated with . Drugs that depress the respiration rate and and and interaction.

Fantastic, thanks Mike. Most of our questions are coming through related to the Sinoni with the PIE. I'm going to group a whole lot of them together rather than going through each individual one, because they, there are a lot of similarities.

How or why would a heart-based tumour not be on your differential in that first, radiograph with a massive tracheal dorsal deviation? Oh, I, I think because the degree of lung pathology, you can see the consolidation of the lung on the dorsomeral lung projection. So if you put those together.

And on the dorsoventral lung projection, the heart doesn't look as though it's being displaced at all. Then I, I don't think I would have been worried about a heart-based mass of any particular size. Of course, you know, maybe, it's hiding a small mass, but you know, those, those I think your major pathology is definitely the lump from those radiographs.

Excellent. The other group of questions is all around, the difference between sort of first opinion and referral and the diagnostics available. If you don't have CT scans, would, a lung FNA or a BAL be, adequate to make a diagnosis?

We would normally go for the BAL first, certainly in dogs, because that's a, you know, fairly, minor but productive procedure. In cats, it's a little bit more, problematic in that, some cats, you know, take longer to recover from, from a BAL than than dogs, and you should be prepared for that. It shouldn't be a high risk, .

intervention by any means, but it's something that you should be concerned about. Fine needle aspirate would be. Our second way of progressing the diagnosis and, and the reason we would progress it is if we, if we have a definite nodular area of pathology that we can identify with ultrasound, then we would do a fine needle aspirin if we hadn't got anything on the BAL.

Or if it's got generalised pathology, I we can't really miss, you know, the pathology wherever we go in the lung, we're going to get it. But the trick with a fine needle aspirate of the lung is that, yes, it may cause, pneumothorax. In our experience, that's fairly low to get significant pneumothorax that requires intervention.

. But you need to be quick, so you need to go into the lesion, suck back a couple of times, come out again. Don't leave the needle in there through several respiration because it will just lacerate, yeah. Yeah.

Yeah, and, and, that, that extended, BAL, recovery in cats, when you said it, it's been many, many years for me, but I've still got that vivid panic feeling in my brain of wondering what I've done wrong with a cat. Yeah, yeah, yeah, yeah. And you know, it's not that you use too much, it's just that they're a lot more sensitive.

I think. Usually they, they, they probably get some bronchial spasm associated with the fluid and that reduces their respiratory reserve a little bit more. So a little bit longer to come around on that one.

Yeah. Another question that came through on that same case was, when you do the CT, how were you differentiating between those small metastatic lesions and your blood vessels, because they were very similar in appearance. OK.

Yeah, yeah, yeah. And that's why I would have liked to have shown the video, which played just before we went on air, and Murphy. But but actually when you scan through from slice to size.

If it's a vessel, then you will follow the vessel. Whereas a nodule, you'll you won't see it, you'll see it, it'll go again as you go from cranial to caudal. You can reconstruct it in, in, in all planes, and again, you'll get exactly the same appearance.

So a nodule is definitely a nodule. The difficulty is the sensitivity of CT. That you can find small nodules that we sometimes call ditzels, which are so small, maybe just about a millimetre in diameter.

In an animal that you know has a tumour, are they secondaries or are they not secondaries? You know, it's just a whole different ball game when you've got that degree of sensitivity, and, and you have to realise that with any diagnostic technique, it has its limitations. Fantastic.

Mike, there are loads and loads and loads of, of great comments coming through and huge appreciation and thanks to you for an amazing presentation. We are running out of time, but I am gonna pop in one last question from Henrietta, and she asks, is there a breed and or gender association with right aortic arches? The, not, not really.

The, the, the gender association is with patconductors, which is more common in males than it is in females. But right aortic arches, you know, these, these are sort of embryological, you know, malformations, and, and they tend to be sporadic. And if I said I'd seen more in German shepherd dog puppies.

That's probably because German shepherd dog puppies throughout my career have been, you know, quite a popular breed, but, there is probably some genetics, but, I think it's more complex than, you know, a simple gene, that's for sure. Yeah. Mike, our time is up.

As always, it has been amazing. It has been an absolute honour and privilege to be able to chair one of your sessions again. And I'm sure if we were in an auditorium, as Anthony always says, there would be a huge round of thunderous applause.

So thank you so much for your time today. Well, thank you everyone for coming along. It's been a pleasure to give this presentation.

To everybody who attended this morning's session on the diagnostic imaging, thank you so much for joining us. We really do appreciate your time. Head over to our Facebook group.

Amy will be, dropping the link in the chat shortly. And, network with the other delegates, ask some questions, discuss some more information and things that you, you maybe didn't get answered, in your question time. And then also please remember that we have 10 webinars available on demand to watch for today and tomorrow.

So don't forget to go and and have a look at those. They are great webinars and it's more CPD for you. And yeah, I hope you have enjoyed Virtual Congress 2022.