this program is brought to you by Hometown Veterinary Partners learn how you can get on the pathway to partnership at Hometown vet partners.com vet candy hey everyone Dr Deja here I'm a vet with Hometown Veterinary Partners we're thrilled to team up with vet candy for this project I remember the stress of preparing for the navi and we're here to support you through it tonight we're bringing you an exciting in topic and an amazing expert to discuss it to find out more about Hometown Veterinary partners and the path to partner program head over to Hometown vet partners.com vet candy best of luck on your test hi everybody my name is Anthony fet I'm the veterinary radiologist and department head of Diagnostic Imaging at the schwarzman Animal Medical Center in little old New York City uh teaching interns and residents is a really big part of what I do I love doing it um I also have a Veterinary consulting company called Veterinary Imaging of New York where we help uh veterinarians from all over the country with their uh radiographic interpretation I'm the Web Master for the American College of Veterinary Radiology it's acvr.org check us out whenever you get a chance and I'm excited to be part of vet Candy's navali prep on Radiology if you have any questions make sure you put them in the chat um so that we can answer them for you and uh what do you say let's get started okay um I would like to thank the interns who are currently rotating in radiology at AMC they helped me with this Naval prep um in terms of finding cases that uh they thought would be helpful for uh taking the test since they took it a lot more recently than I did I haven't taken that test in oh boy oh boy 24 years it's a long time ago um let's get at it I like to call this um basically uh Radiology flash cards okay it's going to be somewhat fast-paced and we're going to go through uh different systems on the common abnormalities that you would see on a dog or a cat I have mostly dogs and cats uh for Preparation today uh sorry no pigs no large animal we can't fit them in the elevator at AMC um let's start with card cardiovascular okay um this is what a normal dog thorax will look like okay um you guys might have um learned about you know what the normal structures should be on a left lateral projection you might have artery bronchus and vein the vein being the more ventrally located structure there's also greater there's a large amount of crossover of the pulmonary blood vessels on the left lateral projection as well this would be artery and this would be bronchus the vein is kind of hard to see for this guy but the veins are ventral and the veins on the VD view are Central so if this is our trachea we bifurcate this is the artery that's the bronchus and that's the vein on this side the artery would be here the bronchus is there and vein somewhere in there that I can't very can't see very well um so yeah that that's uh the ponary blood vessels I'm going to be talking about them soon so that's why I want to introduce that to you guys right away and I could potentially see that on board so you want to remember veins are ventral and Central okay and arteries are away from the cardiac silhouette or more laterally located on the VD projection cats are similar but it's a lot harder to separate arteries and bronchus and veins just because they're smaller um this is the normal thorax of a cat you might notice that the vertebral bodies are a bit more elongated they have straighter humorous and uh they just look so beautiful um I love cats and uh you can you can really separate a lot of the anatomy there's in this guy there's not a ton of fat medius stum this is the Cena and there's your artery bronchus and vein but it's a little harder to see the vein arter is on this side again away or out laterally and uh those those are your pulmonary arteries it's the cardiac silhouette uh liver stomach liver stomach transverse colon here okay yeah and we use U restraining devices to keep them still for a couple of seconds seconds onward what does cardio megal look like what's a big art look like I'd say the most common part enlargement you're going to see is left atrial enlargement in a dog and this left atrium is right here you might have learned the coddle waist of the cardiac silhouette in a dog this is the coddle waist um and this is a large left atrium that is kind of giving us the the backpack sign I think I've heard some students talk about that this V view is a little bit oblique but oblique is okay you should still be able to see things and this rounded butt appearance here that's the left atrium remember the left atrium does not make out the outer margins of the cardiac silhouette the left atrium is in the cardiac silhouette okay so that's that is a potential boards question I would imagine you know you've got um The Border here that's made by the the left Oracle so from here to here it's not left atrium as many people might think the left atrium is going to be right here um and then when the left Oracle is large it'll bulge out and give us a bump here but again it's not the left atrient it's the left Oracle okay um what's the clinical relevance of this well as that left heart gets larger it starts to displace the thoracic trachea dorsally see how it's kind of going up towards the um the Verte column there and that big left atrium likes to squeeze or attenuate the main stem bronchite potentially resulting in a cough in our dogs with uh with cardi megal most common reason for left atal enlargement in most um you know most dogs I'd say classically small braid dogs is going to be mitro valve degeneration he also see in cabis uh mitro valve degeneration uh leading to Ecentric hypertrophy at the left side of the cardiac silhouette and most notably the left atrium in this Cas okay all right so this guy has left atrial enlargement but guess what his artery which is right here and his vein are actually kind of small maybe this guy's on lasic maybe he's just doesn't have congestion yet it's important to look at the pulmonary blood vessels in cases of cardiomegaly because you want to make sure that there's no evidence of congestive part failure or early congestion or distension of the pulmonary vein okay this is a case of a lung pattern we still got that big left atrium okay uh but what's new is that he's developed a lung pattern in his left c a lung Lo remember before we were just talking about what makes the left side of the cardiac silhouette from 1 to 3 o'cl on the VD view you see this little bulge that's forming right there that's a big left Oracle occurring concurrently with a large left atrium so yeah this guy's part enlargement is so substantial that his left Oracle is large as well as the left at and he's developed a Cod dorsal lung pattern which is pulmonary edema until proven otherwise you might notice the pulmonary vein's a little generous right there it's not huge though it is slightly larger though than its corresponding vein uh than its corresponding artery so yeah there's a little bit of congestion there um but uh this this this dog is positive for cardiogenic pulmonary edema we need to treat him and get a necoc cardiogram okay um this is from mitro regurgitation from mitro valve degeneration in general the edemas are codly and dorsally distributed on a lateral view in a dog and the pneumonias are cranial and vental distributed in a dog okay so lung pattern distribution is really what's most important not so much interstitial versus alular that's for another time another lecture but if you can just start to think about lung pattern distribution all these air bronchograms here this lung pattern is you know there's a lung pattern everywhere in this dog with pneumonia but it's most severe cranially inventory that's why we think he has pneumonia in this dog his lung pattern is worse codly and dorsally and there's two types of edemas that we talk about in dogs uh cardiogenic pulmonary edema as well as non-c cartisian pulmonary we'll get to that other stuff later sorry um cats are so tricky cats just never play by the rules this is a cat in congestive heart failure his cardiac silhouette is mildly enlarged how do I teach mild enlargement of the cardiac silhouette in a cat it's really hard even if you learned about vertebral heart scores um they can be tricky and unreliable especially in cats this cat is in heart failure and I feel very confident in heart failure not only because the large heart but also look at these pulmonary blood vessels I'm not going to separate uh you know artery from vein so much but look at how they just kind of make this swish appearance they kind of are distended and and almost look like like cords extending from the highights on the lateral view I like to call that the villains mustache appearance to the cardiac silhouette this is pulmonary blood vessel out here artery or vein they're all going to be big um in some cases of congestive heart failure of cats there's also this slight retraction that we're seeing through the cardiac uh to the pulmonary blood um I'm sorry the visceral plural margin of the lung this guy has a little bit of plural fluid okay and U they'll teach you an emergency that um anytime you have plural fluid in a cat you should always consider congestive heart failure and that rounding right there is another example of plural fluid so plural fluid and a cat you always have to have as a differential congestive heart failure it's just a cat thing guess what not so much in a dog plural fluid in a dog is pretty rare you don't see it every time um you you actually actually very rarely at any time see it with just mitro valve degeneration you will see it with right-sided uh enlargement and right sided congestive part failure but the plural fluid tends to be mild relative to the parital fusion okay so for now just remember you know whenever you've got plural fluid in a cat one of your differentials should always be uh congestive heart failure it certainly helps in this case since the pulmonary blood pulmonary blood vessels are so large and the heart is so large okay how how do I teach heart enlargement to uh beginners it's hard um it's hard to really measure the shape but I can promise you that this is a very large heart because it looks like a valentine right on the VD view you've got this bump here and a bump here and then it tapers to a more narrow uh Apex that's the Valentine shaped heart it works it's a sign of cardiomegaly it tends to uh be associated with a very large left atrium and in severe cases um a large right atrium notice how I said this is probably the left atrium in a cat yeah because cats are different than dogs their left atrium doesn't sit here it sits somewhere in here so when their heart gets large you will see a big Bulch and it will be associated with their Atrium long story short look at the VD View and try to get an assessment for the Valentine shaped heart appearance on the lateral projection sometimes you'll see a little dimple right here before the heart starts to round out and that double humped coddle border of the heart can be a sign of heart enlargement though it's a bit subtler and I can't imagine that would be on the M um okay onward um let's talk about heartworm disease yeah this is a uh Radiology flash card for heartworm disease in a dog you might notice that the lung pattern looks like a Bronco interstitial lung pattern uh the airway margins are clearly visible extending to the lung periphery bilaterally they're partly mineralized there a bit of mineralization to the broncus right there and look at this pulmonary artery relative to the vein remember we said artery is um going to be here that's the bronchus and then the vein is ventral look at how the pulmonary artery is this thick and the vein is this thick let's go to the coddle lung loes on the VD look at this honker of a pulmonary artery right here right here and then that poor bronchus is even being attenuated relative to vein which is right here okay so huge pulmonary artery same thing's going on here it's got a big pulmonary artery large pulmonary arteries you want to worry about pulmonary hypertension the most common reason for pulmonary hypertension you know in dogs throughout the world is going to be heartworm disease in New York City we don't see too much heartworm disease um so we we'll just see pulmonary hypertension secondary to chronic lower airway disease or primary pulmon hypertension but uh in this case when those pulmonary blood vessels those pulmonary arteries specifically are this large you better have heartworm disease on your differential okay so the heartworms it's kind of a misnomer right heartworms they don't really live in the heart they live in the pulmonary arteries and those pulmonary arteries get big because of intima and Tunica thickening U and uh and then then you end up seeing it radiographically the pulmonary hypertension forms simply because of that wall thickening uh the pulmonary hypertension also forms because they throw off little clots and they embolize and so pulmonary thromboembolic disease and lower airway inflammation will contribute to the pulmonary hypertension in these dogs okay oh cat heartworm disease is so tough um you might notice that the pulmonary blood vessels are large I I love I always show this one because look at the pulmonary artery here's the bronchus right here and this is the pulmonary artery man you could drive a truck through that pulmonary artery for a cat that's a huge pulmonary artery this cat does have heartworm disease but I will say that cats never like to um follow the rules they'll have a big pulmonary artery for the first six months and then just look like it'll just look like a Bronco intitial lung pattern you won't see large pulmonary arteries okay same rules to look for though I think it it it's warranted to always have that conversation and if you've gotten anything from this lecture so far remember um uh veins are ventral and Central the arteries are away relative to the broncus so on the VD view the artery is lateral to the broncus the vein is Central um harder to do for the laterals on this we'll have to compare it to prior to to other exams but it was something like artery would be up here and vein would be ventral further down okay all right onward um we already showed a case of this this is mital valve disease in a dog the big large left atrium um he's he's uh I guess that's all I want to say I've already talked about mitro Val disease and dogs okay dilated cardiomyopathy can look a lot like mital valve uh degeneration in fact you know it's one of your differentials when you see left atrial enlargement it still could be DCM it helps to know what breed you're looking at so a classic breed for dilated cardiopathy um I guess I would think Doberman if I saw a radiograph with a big heart in ad Doberman I guess it would be dilated cardiomyopathy until proven otherwise boxers would be another example this is not either one of those but his heart is tremendous and that heart just looks so it almost looks globoid uh has rounded margins it's not limited to just the left side right side is really bellowing forward this is a case of DCM and yes the dog also has cardiogenic pulmonary edema so he's got a D up forming in these Cobble LS um yeah so it can be hard to differentiate DCM uh in dogs from mitro valve degeneration you really need breed to help you uh differentiate the two all right let's go to primary respiratory rather than cardiovascular okay oh we got to talk about feline chronic lower airway inflammation can be either um you know I I was taught when I was a kid when I was in that school it was all asth um but it's not all asthma I think the the preferred term these days is feline lower airway disease and there's two types there's the um eosinophilic form which is an asthma and then there's the neutrophilic form which is a bronchitis and there's radiographically no way to tell between those two uh what you're just looking for is just heavy linear marks throughout the lungs long linear marks that aren't just blood vessels um it starts to kind of look like the nooks and crannies of a of an English muffin okay to give you that bronchial pattern okay and um some lungs uh hyperinflate and some lungs collapse and I will say the right middle lung L which is right here in the sky is totally collapsed it's just a triangular bit of nothing and um collapse of the right middle lung robe is very common in cases of fine Asma or bronchitis so um keep that in mind I I could see that potentially being a board exam question because it's so common for the right middle lung LOE to collapse in cases of feline asthma the thinking is they they produce a lot of mucus and it tends to uh cause a plugging to the Bron ey uh as a result and then and then cause collapse okay so yeah we see a lot of that um dogs we see a lot of this small breed dog with a trachea that just looks so homogeneously soft tissue over this is a small breed dog with a honking characteristic to his cough this dog has conr malatia causing traal collapse super super common uh in our small breed dogs in New York City uh it's not uncommon to see a concurrent Bronco interstitial lung pattern in these guys because chronic acor bronchitis is is very common occurring concurrently with condr Malaysia causing Airway collapse um it's also pretty common to see a large liver this is the liver silhouette see that rounded margin how it extends Way Beyond the castle Arch and causes Cobble displacement of the gastric axis that's liver yeah there's there's different speculation as to why livers become large in animals with tracheal collapse some people think that it um causes a bit of a pickwickian uh appearance and causes congestion from from increase in pressure in the thorax other other people just say that it's probably because these dogs also have vacular hepatopathies including Cushings Disease so um yeah we will see a large liver occurring with uh with tracheal collapse for boards uh for the nav I guess um just recognizing that yeah this this trachea is very small and it you know you might have learned in vet school that there's a dorsal tracheal membrane and yes this is the dorsal tracheal membrane but that dorsal tracheal membrane is coming all the way down to the bottom of the trachea and there's no gas left in this part of that trachea that's because the trachea is no longer a rigid cartilaginous structure it's totally flopped like a SL like a sock so that dorsal tricle membrane is even more prominent and it's attenuating really hard to see on the VD view I don't think I'd ever be able to call it on the VD okay onward oh love this case um this is a dog that is chronic regurgitating and you might appreciate that he's chronically regurgitating because his esophagus which the dorsal margin is up here the ventral margin it's doing something like this right same thing up here here's your dorsal margin um we sometimes talk about the dorsal tracheal membrane that's just because there's gas in the esophagus on the VD view a gas filled esophagus tends to look like a V so so the two lateral walls of the esophagus tend to converge towards the Hiatus and give us a v okay I'll remove those lines so that you can go back and look this guy has moderate generalized esophageal distension because of mega esophagus okay and dogs with mega esophagus love to aspirate and there is a lung pattern sitting right over the cardiac silhouette right here that's pneumonia aspiration pneumonia sometimes in larger breed dogs you don't see the pneumonia over um on the VD view lateral to the cardiac silhouette because they're deep chested you really got to rely on looking over the cardiac silhouette or the their bronchograms to call it okay so yeah that's right middle lung lob pneumonia the right middle lung lobe um is the most common lung Lo for pneumonia in the dog aspiration pneumonia followed by the right cranial lung Lo okay I think that's could be bor fod for sure remember we talked about the right middle lung Lo and cats and in those guys that have asthma that lung lob collapses rather than stays the same size okay so and collapse of the right middle lung LOE is is rare in dogs all right cool yeah mega esophagus in this dog with secondary aspiration oh man I hope you guys are all looking at this from home and can figure out that this isn't normal this is a diaphragmatic hernia uh you can't really see the cardiac silhouette what are feal balls doing in the chest this is the colon being displaced cranially these are gas filled Loops of small intestine combination fat and soft tissue likely representing oh any old abdominal organ and uh and some abdominal or medial fat so this guy has a hi highle um has a diaphragmatic Heria it's so extensive it's really hard to figure out um what caused it I I would guess that it's probably from trauma that that uh that he has this hernia cool pneumothorax along the lines of trauma sometimes dogs and cats get hit by a car um and you will look for uh pulmonary blood vessels that just don't make it out to the lung periphery and then become really really black uh that's gas in the plural space on the lateral projections what you look for is a dorsal lifting of the cardiac silhouette it looks lifted but it's because the collapsed lung from the pneumothorax makes the heart kind of fall away from the sternum so this gas between the heart and the sternum is the numo thorax and I would say you know if you're going to take a board exam you really need the lateral View for the pneumothorax to appreciate it I don't know if the navali is going to have that kind of detail where you'll be able to say the pulmonary blood vessels are making it out to the periphery or not just um remember you know a dorsally displaced cardiac silhouette should be thinking oh man does this guy have a numo thorax okay this guy was hit by a car and he had a bilateral pneumothorax more notable on the left and uh yeah he recovered he recovered fine I know this dog well um we got to about nag lesions right big old soft tissue things look at how perfectly round this thing is okay we call these nag lesions neoplasia abscess or granuloma basically well margined discreetly uh you know often round masses in the lungs okay so it can be associated with neoplasia abscess or granul and in this case it's a primary lung tumor of the r codal lung you can also consider pulmonary metastatic disease I'll lean more towards that if I see more than one and if they're slightly smaller than that um can't rule out granuloma depending on where you live fungal granulomas can look exactly like this so these are your nag lesions this you know in New York City because it's a bunch of Nags it's a bunch of discreetly margined and fairly small nodules um in New York it's it's it's neoplasia but specifically it's metastasis from some cancer somewhere else but I remember you know abscesses can look like this and Gran collect this oh man I can give you a history for this Radiology flash card I know he's young because he doesn't have mineralization of his cartilagenous part of the ribs I know he's young because he does have feces here this guy's just a like a seven or eight months old okay and he's got this fulminant codal dorsal lung pattern see how white the lung pattern is out at the periphery remember what we said before what is the differential what are the differentials for COD dorsal lung patterns those are the edemas right if the lung pattern was worse down here we would be thinking pneumonia this is a young dog with a fulminant codal dorsal lung pattern so I have to worry about two types of Edema cardiogenic and non-cardiogenic the heart's pretty normal in this guy I actually think if anything his heart looks small on the VD view let's talk about it Cod dorsal think EMA ask yourself is the cardiac silhouette large like the case in the bottom here where we've seen multiple cases of right mitol in sufficiency DCM HCM um that that would be uh cardiogenic pulmonary edema causing this increase in opacity but in our dog here he's a puppy he got a normal heart and boy oh boy puppies especially around Christmas time they love to hang out behind the Christmas tree and get electrocuted so this is a non-cardiogenic pulmonary edema um Associated uh with electrocution so you have to worry about electrocution in small dogs young dogs that like to chew things that they shouldn't uh seizuring dogs can also give this lung pattern upper Airway obstruction so like our French bulldogs that come in on a hot Summer's Day they will uh they will have a a choking event near drowning event um and that that can cause this lung pattern as well other things like vasculitis acute lung injury acute respiratory distress syndrome those are all things to think about when you get these fulminant lung patterns cly and dorsally but the heart is normal in size so non-cardiogenic pulmonary edema there's often a history that helps support something like oh yeah he was playing with the fire um you know or he was choked or he fell into the pool and then we um and then we we saved him so these are the type of patterns that you'll see non-card with non- cardian pulmonary edema differentials okay all right so you can rely on the left atrium in dogs we said that you can't really rely on it in cats and here's our left atrium again and I know I'm beating a dead horse on this one but the other time to think about soft tissue in this this area is for another disease okay this is not this increase in opacity that we're seeing on this dog is not because of a large left atrium when you have a large left atrium you also bring up the trachea and the main stem broni see how the trachea here is parallel or coming up close to the vertebral column in this case the trachea is diverging from the vertebral column in fact the main St broni and Corina are being being diverted downward okay times when you see this degree of downward displacement of the K main stem bronchi and no dorsal displacement of the thoracic trachea it's because of tracheo bronchial lymp atop there are tracho bronchial lymph nodes here that are increasing the opacity to the periler region not a large lip Atrium okay so um keep that in mind there another differential for increased soft tissue opacity in this region big lymph node depending on where you live this can be associated with um fungal infections okay this cat this dog had really bad F so that's it for this portion of vet cley's nav prep on Radiology where we covered the cardiovascular and respiratory systems next time we will cover the abdominal and muscular skeletal systems if you have any additional questions please be sure to drop them in the chat uh thanks for joining us today and good luck on your exam [Music]