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On my slides. Um I'll just explain, I'm one of the radiology registrars from Sheffield. Um and the topic today is going to be gi radiology. Hopefully in a few seconds, my slides are going to turn up. Um Are you all able to see that? Is someone able to let me know? Yeah, we can see them brilliant. Ok. Uh Good start. Right. So I'm one of the registrars from Sheffield. Um I'm specializing in gi radiology now, which is something we do in um the latter part of our training, we choose to specialize in a different area. Um Obviously you can go quite deep into the subject matter, but I think I've tried to keep it relatively relevant for medical students and foundation doctors. So thinking particularly about what imaging might be relevant for exams and also for your sort of first years on the wards as well and what sort of pathologies might come up that you might see. Um So I should also give some credit to one of my colleagues. Um Anna Toid, who's one who also helps me to make the slides. Um She's not able to be here this evening, unfortunately. Um but it's not just myself who's done these for you. It's a little group of us. Um, so, yeah, we've mainly tried to focus on the curriculum, um, sort of new national curriculum headings for this. Obviously radiology is not a big part of that, but it's something that's quite important and important on the wards as well. Um, so I try to include some cases towards the end, um, and some time for questions, um feel free to ask questions in the chat box as you go along if you need to. Um And uh hopefully powers will let me know if they're building up and I've not noticed. Um But we'll try and have a bit of time at the end if there are sort of general questions and can wait till the end. Um So in terms of the objectives, um I thought we'll keep it quite simple. We'll look at first assessing the placement of NG tubes. This is something that's done usually on a chest X ray, but it's technically an abdominal imaging thing. Um It may have been something that you've gone over before, but it's a really important um skill and something that you might be asked to do as a foundation doctor. So I think that's why we'll start with that. Um uh Elsewhere, we sort of learn more about um radiological detection of free gas in the abdomen. That's another important pointer for foundation years. Um And then we'll look at some more complex pathologies. So we'll look at the features of things like elis bowel obstruction, volvulus, malignancy, that sort of thing. We'll also have a brief look through trauma which can be quite complicated. So we'll try and sort of skip through some of that and keep it relatively straightforward. Um, so first of all, we're gonna look at nasogastric tubes. Um, so they're extremely important. Um, they're used all the time on the wards often for feeding or putting medications down for patients who are not able to swallow for various reasons. As a result of that, the position of them is really important. Um As I said, they're usually checked on an erect chest X ray. So with the patients that's upright, um it's important because if we put food or we put medications down the tube and it's incorrectly placed, that can have really serious consequences. So, if it goes into the lung, for example, we can give patients terrible chest infections. Um We've actually seen one that went into a blood vessel, um which is quite rare. I don't know how they managed to do that. Um But these things can be really dangerous if they're in the wrong place and it's a really common job to be. Well, I think at the moment in Sheffield, from our perspective, these are reported by radiologists um or radiology registrars. But certainly when I was a foundation doctor in a different trust, we were asked to do them ourselves. So it's something to bear in mind um as you might get asked to do it yourself. So just a brief reassessment of the anatomy on the chest X ray of where we're looking for this tube to go. So, on this um marked image, the green markings are the esophagus sitting behind the trachea. You won't see it very well as you can see on the unmarked image, it's not particularly clear. Um But that's roughly the path you're looking for the tube to follow. And you want the tip to be going into where we see the stomach marked on this image. So below the diaphragm, on the left hand side, that's where you're looking for the tip to be. So I've got a couple of images that are gonna sort of guide us through it. So we look for four key features of a correctly placed tube. So the first one is that it descends in the midline. So behind the heart in the line where we'd expect the esophagus to be second pointer is that it bisects the carina. So the carina is the division in the trachea into the left and right main bronchi. We want the tube to go directly through that central portion because obviously the tube's not in the trachea or we hope it's not. So we want it to be passing straight through that area because it's in the esophagus, not in the trachea. The third thing is that we're looking at for it to cross the diaphragm and roughly in the region of the midline, it's going to be a little bit off center towards the left because that's just the curve of the esophagus. But that's roughly where we're looking. And the fourth feature is for the tip to be lying below the left hemidiaphragm. We usually want it to be not just right underneath the diaphragm, it's gotta be about 5 to 10 centimeters under to make sure that the patient doesn't aspirate food or fluid back up um into the esophagus. So I've got a couple of examples of uh where things have gone wrong and we've got sort of whether they've met certain criteria. So the tube here descends in the midline is the first feature. It doesn't really, it descends in the midline for the first part. Um But as soon as we get to around where the aorta is, I don't know if you can see my pointer. Actually, I'm not sure you can. Um But as soon as we get to the carina, we can see that it's going off towards the left already. It's not dissecting the carina, it's going straight down into the left side of what looks like the chest. Um And the tip is not below the diaphragm. The tip is right in the bottom here within the lung. And this is an example of a um misplaced tube which is in the left lung, it's gone down the bronchus and out into the periphery of the lung. And I think it actually caused a pneumothorax on that image as well. So next image is another sort of commonly encountered type of tube issue. So, um again, it doesn't really descend to the bottom of the chest in the midline, doesn't bisect the carina, it's curling around and then going down the right main bronchus. So it's again not crossing the diaphragm and it's not uh the tip is not below the diaphragm either. I think this is another similar one where we've got the tube sort of descending in the midline for a reasonable way. It does look to dissect the carina, but then it's coiled and sweeping back up. You can see it much better on the marked image where we've marked the tube in green. Um But that's something to look for. If you see a coil in the um in the tube, I think this is the final example. So this one is not too bad in many ways, it's going down the midline, it's bisecting the carina. You might argue that it's just about crossing the midline. The tip is just below the diaphragm, but that's roughly where we would expect the gastroesophageal junction to be. So, as I said before, we want the tip to be at least sort of 5 to 10 centimeters below. So very well below that diaphragm because we want it to be firmly in the stomach, not at the junction, uh the gastroesophageal junction because in that case, when we put food or fluid down, it can easily just aspirate straight back up the esophagus and into the lungs, potentially. Oh, no, I thought that was the final one, but we've got another one. So in this image, similar issue, um it's gone all the way down, we can see it crosses the midline, um crosses the diaphragm in the midline, but then it's coiling around in the stomach and the tip is not sat below the left hemidiaphragm. This is an example of one that's probably too far in. So the tip is probably sitting in the duodenum rather than in the stomach. That's less of a problem because it is in a safe place. Um But usually we try to pull those ones back so that it sat in the stomach. Um just in terms of how well fluids and food are tolerated when they're put down the tube. And finally, a correctly placed tube should look like this descends all the way to the diaphragm in the midline. It bisects the carina and the center, it's crossing the diaphragm roughly in the midline and the tip is well below the left hemidiaphragm. So that's what you're looking for. They're often features that you'll see in a report from a radiologist. They'll usually mention these things. They might say the tube bisects the carina. Um the tip is below the left hemidiaphragm in a safe position for use. And if not, they'll usually state in an unsafe position and needs to be removed. So we'll move on. Um, the next sort of quick section or skill that I wanted to go through is just looking for free gas. Um, on pneumoperitoneum, I was asked to do this a lot as a foundation doctor. Certainly on surgical jobs where you're doing lots of x rays for patients that are coming in with abdominal pain, you're worried about perforation of the bowel or gi tract. So you're looking for free gas. So on an X ray, uh should be within the stomach and within the small and large bowel and they have sort of distinct patterns for pneumoperitoneum assessment. We usually would do an erect chest X ray again. So again, not quite what you'd be thinking with abdominal film. And that's because the gas will rise up to the top of the abdomen and we see it below the diaphragms here. And this is a really good example of free gas below both diaphragms causing a sort of arc shape of the diaphragm. You usually don't see the diaphragm that clearly on an X ray. So that's a sign that there is free gas. Another sign that we look for is called R sign. Some of you may have heard of it, it's sometimes mentioned. So the main thing with R sign is that when you have gas on the outside and also on the inside of an organ. So for example, the stomach or bowel, you've got gas on the inside. But if you've got gas on the outside as well, that shouldn't be there. You see rigorous sign, which is, you clearly see the outline of that organ much more clearly than you normally would. So here on the left side, below the left hemidiaphragm, you can see the outline of the stomach is very clear and that's because there's gas on both sides of the lining. So also free gas on the outside. Finally, I think my graphic has not worked at all here. So we might skip on from that one. But the football sign um is basically you get a large on a, on an a abdominal x-ray where the patient is lying flat, you'll see a spherical appearance of free gas. Um Unfortunately, I think my graphic has not worked very well there. Um So I will skip on the final sign that we look for with free gas is called the falciform ligament sign. Now, the falciform ligament is um a ligament within the liver which divides the right and left lobe of the liver. We normally would not see this on an X ray. Um It's something that's just not visible, but as the blue arrow points to the line there, that is the ligament seen within the two sides of the liver, you shouldn't be able to see that normally. So that's a definite abnormal finding and that means that there's free gas, there's also an element of a football sign on there as well. You can see a rim of gas forming a spherical shape because that's all risen to the top of the patient while they're lying flat. So those were just a brief sort of recap of topics that you might find elsewhere on sort of chest imaging mentioned. Um But I thought they'd be good to go through as they're sort of some of the most relevant gi sort of abdominal presentations. Um So now we're gonna go through some more complex presentations, things that you'll probably have either seen on the wards talked about in lectures, that sort of thing. They are all quite common some more than others. But there are often things that um are queried when patients come to hospital with an acute abdomen, abdominal pain, abdominal distension. Um So I thought we'd go through some of these um conditions and look at what imaging findings look like in a brief sense. Obviously, you're not gonna be expected to diagnose things on a CT when you're starting in your foundation years, but it's useful to have some pointers and to understand um what we're looking for. So, uh the first one is ileus and ileus is failure of the passage of gastric contents through the small bowel and colon when there is no mechanical obstruction. So this is basically a sort of failure, a paralysis of the intestinal motility. Everything's just sort of slowed down the bowels not working as it properly should. Um, but there is no actual blockage, stopping things from passing through. It's just going a lot slower than it should do and things are getting a bit backed up. So, in terms of how these patients present can be asymptomatic, um, they can present with nausea and vomiting, progressive abdominal distension as things are backing up, um, reduced bowel movements and they can have reduced or absent, bowel sounds as well. So a little bit like, um, bowel obstruction, we'll talk about that afterwards. Um, in terms of the causes, the most common causes are usually things like drugs, medications we give people specifically, opio opioids are really bad for this. Um, which of course, a lot of patients are on, especially if they've had surgery, surgery in itself is another cause. So patients who've had surgery are doubly at risk really. Um, and it's quite commonly seen after surgery of all types. Um, usually abdominal surgery. Um, and the final one is sepsis. So any kind of infection can lead to this sort of slowing down of the bowel. So I've got an image here just to go through some of the X ray features. Um, so what we're looking for really an ileus is a sort of generalized, uniform gaseous distension of the large and small bowel. So there is no mechanical obstruction. So we're gonna see the colon and the small bowel start to distend and fill with gas because things are backing up slowly as things are not passing through. Um, you'll get definite involvement of the large bowel. Um, and there'll be no, what we call transition point. So I'll talk about that a little bit more in a few minutes. But the transition point is something we look for, uh, particularly on act scan when there's an obstructed bowel. So we look for an area where the bowel goes from being dilated suddenly to being collapsed. And that's because usually there's some form of obstruction. So we shouldn't really see that in this condition, we should just see generally slightly dilated bowel loops that are enlarged and starting to fill with fluid, um, just move on. So this is a sort of still ct image. It's not the best way to show you this. Um I was hoping to get some images that sort of scroll through the CT, but that can be quite complicated. Um So I thought we'd just keep it fairly simple. Um All the sort of loops and sort of gas filled areas at the front of the CT are bowel loops, they're all larger than they should be. Um, and they're all either gas or fluid filled. So things are backing up. We've got gas and fluid in the abdomen. Um And that's just an example of how this would look on CT. So, moving on now to bowel obstruction Um, I'm just gonna pause, have a quick sip on my water and I'll be back in a sec. Ok. So bowel obstruction can have really similar appearances to ileus and they can be hard to tell apart sometimes. Um, but this is when the passage of bowel contents is blocked. Um, and there are various different things that can cause the blockage. I'll go through some in a minute. Um, and it is usually a surgical emergency. Um, because when the bowel is mechanically obstructed, it needs to be decompressed quickly. Um, otherwise it can lead to, um, eventually backing up within the bowel distention. And that can lead to perforation of the bowel. So, can occur in the small or large bowel, small bowel obstruction is much more common. We'll just move on to look at some of the causes. And so I've got the presentation first. So presentation will usually involve abdominal pain and distension, vomiting. Um, as there's no other way for the bowel contents to come out. So eventually, once you get very backed up, you start to vomit and what we call absolute constipation. So not passing any stool and not passing any wind either in terms of the causes, the biggest three causes. And they're sort of important to learn for your medical school placements and exams because they'll come up a lot. Um, the first one would be adhesions. So these are sort of scar tissue, uh, within the abdomen from previous surgeries usually. So, if a patient's had any previous surgeries, like a cholecystectomy, um, c section, um, any other kinds of abdominal surgery, they can be at risk of adhesions. Um, hernias is the next one. Um, most types of hernia can have bowel within them and that can be cut off at some point and cause obstruction. The final one is malignancy and that's more and more common as time goes by. Um, so developing a tumor and eventually it gets so large that it will either compress the bowel from the outside, um, or it will fill the lumen of the bowel and prevent anything passing beyond it. Other less common causes would be things like volvulus, which we'll talk about later. That's rotation of the bowel, uh diverticular disease strictures which are narrowings within the bowel fibrotic narrowings which occur in diseases like Crohn's disease. And um, another one that will come across later into su exception, which is where the bowel invaginate into itself. So, thinking first about small bowel obstruction, um, it accounts for 80% of mechanical bowel obstruction. So it is much more common you're looking for on an X ray, um, dilated loops of small bowel. So this is quite common thing to do when patients come into A&E initially. Um, they may have an initial presenting X ray to look at. Um, they would need a CT to properly look for a bowel obstruction. Um, but you might be asked to give your opinion on an X ray. Um, to say whether you think the bowel looks dilated or not. Um So small bowel loops should only measure up to six centimeters at their very maximum diameter. Um They shouldn't be any larger than that. They also should be predominantly in the center of the abdomen, but they can be all over as you can see from this image but predominantly central. And you should be able to see the valvular convenes, which are the little lines that go across the small bowel. Um, the little folds, the way to tell them apart from large bowel is that these ones go all the way across the bowel from one side to the other. Um And they create when the bell's dilated, what we call a sort of stack of coins appearance. So they sort of stack up one on top of the other, um, similar appearance to that large bowel obstruction, X rays will differ. Obviously, it's the colon that's descended. Um But you may have some small bowel distension as well because obviously that is proximal to the colon. Um You might be able to see the Haustra which are the folds within the large bowel. They differ from the valvulae cones by the fact that they don't cross the entire bowel. So you'll see lines that go part way across the dilated loop of bowel, but not all the way across from one side to the other. Um You also might see some colon that's collapsed distally to where the blockage is. I don't think on this image we can see any of that. Um And similarly, you may have little or no air in the rectum uh in the center because no gas is getting through. And you may see small, small bowel dilatation, but it depends on whether the ileocecal valve is incompetent or competent. So that means whether the valve in the ileocecal region is open or closed for content to go through. So the final thing also to touch on with bowel obstruction is what we call closed loop bowel obstruction. This is much more of a sort of radiological and possibly surgical thing. Um So this might be a little bit more detail than you need, but it's useful to know. So this is something we really worry about. Um, it occurs when there's a, there are two points of obstruction within the bowel. The segment of B between those two points of obstruction will start to distend massively because the content cannot go either way and it can lead to quite commonly leads to perforation of the bowel. Um, which means that content goes into the abdominal cavity that can cause a horrible sepsis and can be lethal for many patients. Um It can also cause bowel ischemia as well. So, in cutting off two segments of the bowel, um the blood supply to the bowel in between is often cut off as well, and that can lead to, um, ischemia of that particular bowel loop. So it, the only other circumstance when it can occur that's worth mentioning because it comes up sometimes in medical school, um, is in the large bowel, if there's an obstruction distally in the large bowel and the ileocecal valve is what we call competent or shut. Um, then there won't be any spillage of content back into the small bowel. So it can't be decompressed. So the whole of the large bowel will be, um, starting to dilate um, and be obstructed at both ends. So I mentioned bowel ischemia just a few minutes ago. Um, obstruction is one of the causes of it, but there are several others, um, things like um clots within the blood vessels. So, emboli um atherosclerosis within the arterial system, hypoperfusion because of either a bleed or trauma. Um, and other things like closed loop bowel obstruction. Um in terms of how it presents usually with abdominal pain, bloody, diarrhea is the common presentation. Um, but also hypertension, possibly a raised lactate in the patient as well. So I'll just actually go back for a sec. So, on the images that I've got over here, we've got um, a ct of a patient and then the um a live image uh that was seen in surgery. So you can see all the sort of black and dusky areas of the bowel on the surgical image, all those areas are dead and that bowel will have to be removed because it's usually not recoverable by that stage. Um, so it's really severe for patients and something that we try to spot early on. So things that we're looking for when we're looking for bowel ischemia are things like bowel wall thickening. So I think that's a little bit better seen in the previous image. I'll just go back to it where the arrows are pointing. There are multiple loops of bowel that have got thicker walls than they should have. Sometimes we also see gas within those walls and that's called pneumatosis. Um And that's because the necrosis is causing gas to develop within the bowel wall itself, that gas can track back via the blood vessels and go into the liver in the portal venous system. So we'll see gas in the portal venous system. The other thing we might see when the bowel wall is broken down because it's necrosis is perforation. Um And free fluid and bowel contents within the abdomen. We do what's called a triple phase CT for this. Um That's a type of CT scan that gives contrast in three different phases. So essentially we do um a scan in a non contrast scan. Initially, we'll then do a scan with contrast in the arteries and then one with contrast in the venous system that just helps us to see um if the bowel wall is enhancing normally. Um So we're looking on the arterial phase to see whether there is blood flow to the bowel wall essentially. And that's something that will come up when you do surgical jobs and foundation um, radiologist may ask you if that if you have concerns about bowel ischemia, because if you do, we do a slightly different type of CT scan, this type of CT scan. Um So it's a specific scenario, there are also these areas um that we call watershed zones. So if you know much about the blood supply of the bowel, um particularly the colon is um supplied by different vessels. Um So superior and inferior mesenteric arteries supply different sections of the colon and where those sections cross over, we see um ischemia uh in watershed areas um is what we call them. So we might see ischemia more commonly there because they have a slightly poorer blood supply. So areas like the splenic flexure particularly. Um So moving on to another sort of acute abdomen presentation. Um So that's interception might be something you've come across. Um It's often a bigger to topic in pediatrics um as it's quite common in Children. So this is when one segment of the bowel is pulled into itself, um or into a neighboring loop, it's really um common in Children compared to adults, but it can happen in both. Um And it can also lead to bowel necrosis if it's not treated swiftly. Um The most common location for it is in the Ileo colic region. So where the small and large bowel meet in Children, we usually see it between about four months and four years of age, but it can happen at any age. Um And when it occurs in adults or older Children, um, it's usually as a result of a bowel lesion, um, which we call a lead point. So, um, in younger Children, we don't really see this, but in adults and older Children, if there's a mass within the bowel. Um So on this diagram here, I've drawn a little mass which is labeled lead point. That's just another word for mass. Basically, that um makes the bowel, we think it makes the bowel more likely to peristal and invaginate on itself causing an intussusception. So, in Children, young Children, the cause is usually due to what we call hypertrophic or overgrowth of the lymphoid tissue during an infection. We can't actually see that on imaging. That's something that's too small and too indistinct for us to see. So usually we don't see any, any cause in Children in adults. It's often due to a mass. As I said, that can be bowel, malignancy can be other types of bowel lesion like polyps, um lipomas, so fatty lesions, um or congenital things like the presence of a Meckel's diverticulum. In terms of presentation, it's very similar to the others intermittent abdominal pain that can be intermittent because the bowels going in and out of itself, vomiting. Um A mass. And also a classic presentation is what we call the red currant jelly stool, um, which is a jam like looking stool. And that's because it's, it's got blood within it. Um, so this is commonly assessed on ultrasound usually. And that's because we're often dealing with Children. So we don't want to use radiation if possible on ultrasound, we're looking for several signs. The first one I've demonstrated on a picture here is called the target sign. I don't know why it's come up as target sound. That's my mistake. Um So we're looking for a target a bit like a bull's eye sort of shape. So we'll see a round circle with another round mass within it. So that's the appearance of the one loop of bowel being within another loop of bowel. So we call that the target sign. Um We also look uh with Doppler imaging to look for blood flow within it. Um to see whether the bowel is still alive or whether it's necrosing and dying because the blood supply has been cut off. Um The other thing we look for is called the pseudo kidney sign. So um on the, I think if it's come up correctly, um the first image is an image of an interception within a child, um which looks very indistinct, but I hope you'll agree that it looks very similar to the second image or it can do, you might have to take my word for that Um And the second image is of a normal kidney within a patient is labeled right kidney. So these things can often look just like a kidney on ultrasound for some reason that we're not particularly sure about. So, it's important to mention fluoroscopy when we're doing this because this is really important in diagnosis and treatment of an intussusception. Some of you may have seen fluoroscopy, not many of you are likely to have because it's something that it's not particularly used as much these days. Um, so what it is is the use of, um, an X ray machine that can move around the patient on a bed. Um, and we usually use contrast. Um, so sort of dye that goes within the bowel. Um, in this case, what we do is we use air and a contrast medium. Um, it's introduced into the bowel via the rectum with a rectal catheter. Um, we use this to diagnose the interception. So we might be able to see that bowel within bowel on the imaging and we also use it in Children to treat it. Um, so they use high pressure air to inflate the bowel and to hopefully, um, pull out the pressure, hopefully, opens out the bowel a little bit like when you blow up a balloon and you enlarge the balloon sac by blowing into it. Um, it avoids surgery and it uses a lot less radiation than a CT scan. So that's something we use a lot in Children. But if there's, um, if there's a large mass, if it's not reducing with the pressure, or if the bowel is starting to necrose, then we have to take the patient to theater and do it that way. Um This is act of a patient just so you can get an idea of what it looks like on a CT scan. Um, we usually use CT in adults. Um, and we're again looking for what we call this bowel within bowel appearance. So this large sort of lumpy mass like area in the middle of the abdomen with the arrow pointing towards it. That's the appearance of one bowel loop having gone into another. Uh So next, I'm just gonna mention volvulus. Um You might have heard of this. It's a condition where the bowel sort of twists around itself and the mes Ry that's attached to it. The me and tree is a membranous peritoneal tissue that connects the bowel to the posterior abdominal wall and the blood supply to the bowel goes through the masonry, which is important as again, the twisting can cause bile ischemia. Um Just by the very nature of the twist, it causes what we call aba closed loop, bowel obstruction as we mentioned before because it's twisted, the loop is obstructed at both ends. So again, it is quite a high risk problem. There are two types, sigmoid, volvulus and cecal volvulus. So, risk factors include things like neuropsychiatric disorders like Parkinson's disease. Um being resident in a nursing home, I'm not sure why, but probably sedentary lifestyle, things like that. Chronic constipation, a high fiber diet, sometimes pregnancy as well. Um, presentation again similar to the others that we've mentioned as it is a type of bowel obstruction, vomiting, abdominal distension, pain, constipation. So sigmoid volvulus, um is much more common. It usually affects older patients, um, usually caused by um chronic constipation On an abdominal X ray. We're looking for a really big dilated leu of colon can have gas fluid levels in it. So we'll see gas above and fluid lying flat below and what we call the coffee bean sign. So on this x-ray that I've put up, um I think unfortunately, my graphic has not worked very well. Sorry. I think I've moved on too quickly, but essentially we're looking for um, a shape that looks almost exactly like a coffee bean. So you'll see um, a sort of circle of dilated bowel with a line running down the middle. Um And that's two, that's one big dilated loop that's folded back on itself and that's a classic appearance of a volvulus. So, something worth looking up because it'll probably come up in exams. Uh The other less common type is a cecal volvulus. So that's when we get rotation of the cecum. So the area that's the base of the colon around the ilio cecal valve usually affects younger people. Um, very similar appearance, um just a different location. So a large dilated loop of bowel like we can see in this image here. Um But it will be usually arising from the right lower quadrant and going pointing up towards the left, lower quadrant. Um And that's just because of the origin of where the cecum lies um in the right lower quadrant. Uh Next thing I'll just go through is a very small amount on sort of colonic tumors. Um They start from developing polyps. Um polyps are as I'm sure you all know, sort of benign entities, but that can advance towards being malignant. Uh One thing we so things we look for um in the bowel on imaging, um polyps look circular solid lesions within the bowel, they can sometimes be pedunculated. So on a little stalk, the other thing we look for when we've got advanced malignancy is what we call an apple core lesion. So on the second image uh of the bowel at the bottom looks like there's almost a chunk taken out of it like an apple core. Um And that's because the malignancy has thickened, um the bowel wall and has created a really small lumen because there's all tumor built up around the edge. Um In terms of imaging, we use it for diagnosis of colonic cancers staging and follow up as well after treatment. Um We do things like enemas um using fluoroscopy. So, X rays um to look for lesions within the bowel and we also use types of CT. Um And there's some examples at the bottom of what a little pedunculated, fibroid looks like on CT rectal cancer is something you probably don't need to know much about in terms of on imaging. Um Just good to know that what we mostly do for rectal cancer is MRI imaging because it's very difficult to see rectal cancers on a CT scan partly um by the fact that the rectum is usually collapsed in a patient. Um It's an area of the bowel that's um usually empty when we image the patient. So, MRI scanning is much better than a CT scan. So we've gone through the sort of um abdominal, acute abdominal presentations. The next one I was gonna quickly go through is abdominal trauma. Um My colleague has made these slides and they can, I think they go into possibly more detail than we need. So I won't stay on them for too long, but we'll go through a little bit. So, um firstly, abdominal trauma, this is a sort of graphic of act and some of the findings that we're looking for. So I'm thinking particularly about high energy trauma. So things like road traffic accidents, um falls from height when the abdomen's had quite severe, um treatment. Things we're particularly looking for are free gas. So, pneumoperitoneum because that signals that we've had rupture of the gastrointestinal tract, either the stomach or, or the bowel at some point, we look for lacerations um within the major organs. So things like the liver, the spleen the kidneys and they of course, can be associated with hemorrhage because they're tearing parts of the organ tissue. Um And we also look for active bleeding from those areas. Um So I'll just move on to the next slide. Um Some of you may or may not need to know we do a slightly different type of CT scan when patients have had high energy trauma, we call this um Act Bastion Protocol. Um that's named after Camp Bastian in Afghanistan, which is I think where this particular type of CT scan was pioneered. Um It's not something you really need to know about. Um It's just, you might hear it said when you're in foundation years. Um It's just a particular timing of giving patients contrast to try and see injuries in the most clear fashion on the CT scan. Um in terms of the spleen, that's an organ that can be d badly damaged and trauma. Um, bleeds from the spleen can be really catastrophic because obviously the spleen has got a high amount of blood in it at any one time. Um So we look for things like lacerations on this CT scan. You can see a dark line through the spleen. That's what a laceration would look like on a CT scan. There's also a lot of sort of gray looking fluid around it that shouldn't be there, that's all blood. Um So that's hematoma around the outside of the spleen. Um Things like rib fractures next to the spleen can cause trauma to the spleen. So even if someone's just got rib fractures, we still have a good look in that area because they can lacerate the spleen. Um There's various grading systems of splenic injury. I won't get into it with you because it's much more complicated than you need to know. Um But basically, we're looking for tears within the spleen and bleeding from it. Um We'll just move on from there. Um Liver, similarly, that's a sort of solid organ. Again, we're looking for lacerations, um Bleeding, you can also bleed an awful lot from your liver because it's got a very uh strong blood supply. Um These are some images of blood within the liver. Uh There's a grading system again. Um So everything from, there's a bit of blood on the outside of the liver to blood within the liver. And that's all this area of low density on the sort of grade three and grade four images. On the grade five images. There's a large amount of low density within the center of the liver that indicates a high amount of trauma, loss of bleeding. Um and sort of rupture of the liver, kidneys again, similar looking for cuts or lacerations, bleeding around the kidney. Um Mostly those sorts of things as well. Um If we've got many lacerations within the kidney, as seen on the sort of grade five image. Um, the kidney can become sort of detached from its own blood supply. Um, and shatter that's called a shattered kidney and that kidney probably can't be saved that would need to be removed surgically to stop the bleeding. Um I'll skip over this slide, but the other thing we can get with trauma to the kidney is um leakage of urine. So if there's damage to the proximal ureter or the renal pelvis, we can get urine leaking out into the abdominal cavity and that can cause sepsis. Um And it can be quite nasty and even fatal for patients. Pancreas is another area commonly injured in blunt trauma. So things like bike handlebars, steering wheels, seatbelts, um looking for lacerations to the pancreas and trauma. Um These are just different locations of lacerations we can get within it. Um The pancreas is quite hard to see on CT um when you're first starting to look. Um but it's this sort of central floppy looking organ, it's like a thin ribbon shape. Um And yeah, essentially, we're looking for similar things, cuts and lacerations within it. Um We can also get damage to the bowel and the Me Ry, which we were mentioning before we can get perforation of the bowel um due to either blunt trauma or something like a stabbing. Um So we're looking for free fluid and free gas on the outside of the bowel that suggests the bowel has ruptured. Um, I've got a couple of cases. I don't know if, um, it's a good moment to sort of go through some of them. Um, I can open the chat box, I think and see if anyone puts some answers in. So I'll go through the cases, um, just for a few minutes and I'll try and leave a few minutes for any questions at the end. Um, we can go through nice and briefly. So case one is um a patient who's recently had an energy tube put in. Um So thinking about the principles that we mentioned before, um any suggestions on whether this tube's in a safe place, not in a safe place and where it is, I think the image is quite small. So I apologize for that. But if you can zoom in, please do. Yeah. So I'm just looking at the chart, um answers look pretty good so far. Yeah. So the NG tube is looped uh into the left and then right bronchus. Yeah, that's perfect. So um it's gone down one side, it's looped and it's gone down the other um other main bronchus. So that would be in an unsafe position. Um Sort of goes without saying but indicates very strongly that it's in the trachea and needs to be removed. Um I'll just go into case two. This is a slightly more complicated case. Um This is a scan that I saw recently. This week. Uh So I just thought I'd put it in. Um This was a patient that presented with abdominal pain um and distention. Um They were a young patient in their twenties. Um This is a CT scan uh in axial and sagittal views. I'm not expecting anyone to get the answer to this because it can be quite hard. But we have gone through some of the imaging findings um in terms of sort of giving you a clue, pointing you in the right direction. Um As you're looking at the scan, the main abnormality on the axial image. So the first image is on the right side and we're looking predominantly in the bowel loops. I think this is quite a tricky one. So um if we've not got any suggestions, oh hang on, we might have a suggestion. Um I will just go through it myself. Um So the first thing I would notice about this scan is that all the sort of rounded bowel loops that we're seeing look larger than they should be. Now, that's something that you get used to when you see more scans. Um But essentially, they're all quite dilated the ones that we can see. Um And in the right side, there's one particular loop which looks really thickened on the far, right. Um And it looks like it's not got the same density of fluid within it. It's much more dense than the other bowel loops. Um This is an interception. Um, so the bowel has gone into itself. Um, and this was caused by a mass. Um, so that density that we're seeing on the inside was a, was a malignancy. Um, so this was a relatively young patient, I think they were in their forties. And, um, this, this was the first presentation of cancer, um, with a bowel su exception. Um, next case that I've got is probably a bit more of the right level something you might see in an exam. So a patient presenting with abdominal pain, some vomiting not been passing wind. Um So we're thinking about bowel related problems. Um Can anyone suggest what they might think about the the X ray? Yeah, so brilliant. We're getting lots of answers. It's definitely small bowel obstruction, the loops are all central. Um They do have the valvular convenes that are going across all the way across the bowel. Um And in keeping with that stack of coins signs, that's perfect. Um And we can't see any sort of big loops of colon on it cos presumably that is empty. I can't remember if I put another case in. Um It's just another quick one. a patient presenting with an acute abdomen into A&E we've done an initial chest X ray looking for um infection. Yeah, brilliant. You're all obviously still awake. Um There's free gas, pneumoperitoneum. Um There's arcs of gas under both diaphragms. That's brilliant. Um So these are my references. Um just for most of the images. Um And that's the end. Um So, I don't know, I'm happy to take some time for questions now if that's all right with uh Paris. I don't know if there are any that I missed on the chat. Um I'll have a look back and see if I can see any. Yeah, that's fine. Um If anyone has any questions feel free to either unmute or put any questions in the chat and I'm sure Fran will be happy to answer them for you and I've sent out a feedback form as well also. So if people can fill that in, then you'll get attendance certificates afterwards as well. Brilliant. Um, yeah, happy to take questions either about sort of related to the powerpoint or if anyone's interested in asking about, um, radiology training, that's happy to answer any questions about that.