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Hi, everyone. I think we'll give a few more minutes for people to join. Then we'll get started. Okay. Good evening everyone. Thank you for joining our first talk for a series of, uh, I our bikes this year. Um, we are joined here by Doctor Rent who is a radiology registrar at Southampton General Hospital. And he'll be talking to us about the fundamental principles of interventional radiology. Um If anyone has any questions during the talk, just put it on the chat and I will read those out at the end. Um, and we can go through those at the end. I'm gonna hide you over to right now. Hi, everyone. Uh My name is Ren. Thanks for the introduction. So he, so I'm one of the radiology STT based in Southampton at the moment. So I'm hoping you can see my, I'm sharing my presentation. Yeah, we can say that. Cool. All right, apologies. I did try to turn on my camera, but I think the computer at work has banned the website from turning on the camera for some reason. So, yeah, I apologize for that. So today I'll be talking about the fundamental principle of intervention radiology. So, uh first of all, I'll start with just talking about the basic vascular anatomy and now focus mainly on the neck vessels and the femoral vessels because that's where we do most of the punctures in I R. And after begin some basic knowledge of the vascular anatomy, I'll talk about how do we actually gain access into the vein or the artery? And then I'll show you a picture of what a typical intervention radiology theater looks like. And I talked you through all like the different parts and components within it. And then last but not least, I'll briefly run past like common, commonly use shift wires and catheters in I R. All right. So we start with the vascular anatomy in the neck. So on the left of your screen, you can see a very nice illustrative pictures demonstrating the common critic arteries of the in the red here and the internet jacket low vein in blue and you have the other structures within your neck as well. So in the middle, have your airway, your truck here and the esophagus behind it. Obviously, you have your tire, it looks as well and the other neck muscles either anterior and posterior and some of the fats around. And if you imagine if you put the ultrasound probe on this area of the neck perpendicular to the vessels, you will get a transverse view of all the neck vessels and the surrounding organ and it will translate into these pictures here on your right hand side. So obviously, we're mainly looking at the common carotid artery and the internet jugular vein. And there's some useful tips and tricks to differentiate which one is the artery and which one is the vein and usually the artery is medial to the vein. But that can be misleading at times depending how you position the probe and the patient's position as well. So other methods to differentiate is as we all remember from medical school, the artery a war is stronger and more elastic than the vein. So it always most likely appear to be like rounded, where else the vein is not. And other more reliable method is because ultrasound is a dynamic study. If you're ever in doubt, you just have to gently put a bit more pressure on the patient's neck and then what you notice is the vein will sort of collapses whereas the artery will remain open. Okay. Hopefully, that makes it clear. And then obviously, when we are doing the puncture, we don't really need to see stuff like the tire oid or all this like neck muscle at the back. What we want is just the vessel as big as possible, right in the middle of the screen somewhere like this. So that's the common carotid artery because it's in the media site, it's like demonstrated on these pictures here. And that's the internet jugular vein on the latter. And again, if you ever indulge, just put some pressure off the, on the patient skins and eventually collapse nicely and the Arthur will remain open. All right. And usually when you do the puncture, the needle on this bigger needle will come somewhere from here in this direction. And then when you visualize the tip of the needle, you just have to puncture into the vein and then you get access into the vein and now we shall move on to the an atomic in the femoral vessels. So once again, illustrative pictures, the head of the famous right in the middle and you have lots of different muscles in different compartments of the ties. And we are focusing on the vessels and enough. So there's lots of way to remember the orientation of the vessels of the wind. The one that I remember from medical school is the Pneumonic Vance O V A N coming from media to letter. So it's the vein artery and nerf. And now if you imagine we put the ultrasound probe on the patient's skin once again perpendicular through the vessel. So the transverse field this is what we get. So you have the artery bit more round that then the common femoral vein looks a bit flatter and always if ever indulged, put a bit gentle pressure on and the venture collapses and the artery will remain opens. And now this is a long access of view or a long gated interview of the common femoral artery. So if you imagine initially where the probe is perpendicular to the vessel. Now, if you rooted the probe 90 degrees, so that the probe is parallel to the vessel, and this is the view, you will get like an elongated view of the artery. So that's the common femoral artery and then it will branch into a superficial branch and a deep branch. The superficial branch being a superficial femoral artery and the deep branch would be the profunda femoral artery. And where we usually do the puncture in I are, we tends to puncture the common femoral artery. And what we want on the images, we want to have the head of the femur somewhere behind it as well. Because if you imagine you're coming through with the needle here where you want to puncture the CFA just around here, what you want is a very solid platform on the back. So that would be the head of the femur. So that's easier for you to puncture because it's probably lots of extra like support and stability when you try to do the puncture and different operators has different matters of puncturing the CFA. Some of the consultants prefer to, first of all put it into the long axis view, guide the needle to somewhere around here just above the femoral head and then they'll go back to the transverse view and try to get the needle right in the middle of the artery before they puncture into it. Some consultants prefer to do everything in just the transverse view, but that takes a bit of time to get used to where you have to keep pending the probe towards the head or towards the toe to try to find the tip of the needle and then puncture the artery from that. And where are some consultant prefer to do the whole proceed. Uh do the whole puncture just on the long axis. View every method it's safe. As long as you can visualize the artery and visualize the tip of the needle so that you know where you're going and not damaging the surrounding structures. And uh in intervention cardiology, they like to use the radio artery as their side of puncture in I R B. Very rarely used the radio artery. That's because mainly it's just it's smaller competitor, common femoral artery, but sometimes we do use them if needed. And now that we have some knowledge on the vascular anatomy, I'll talk about how do we actually get access into the vessels. So now, basically this uh the Seldinger Tank is the most widely used technique to get into the vessels. And it's created or pioneered by a Doctor Seldinger, a Swedish radiology consultant back in the 19 fifties. And now it's the most vitally technique used in the world. So to do this, first of all, you need to puncture the desire vessels or it could be either like a fluid collection or cavity. So for example, it could be like interact um in a abscess or like a liver abscess. Or sometimes if the patient has like hydronephrosis iss, you want to put a nephrostomy into the kidney, that's all part of like Seldinger technique as well. So you have punctured into the lumen with a needle and once the needle is in place, depending what you are puncturing, if it's in the artery, you have blood squirting out. And if it's a vein, then you might have just a bit of blood oozing out. And if it's like an abscess, you might have puss coming out. And immediately once you get access into the lumen, you pass a wire through the needle and push it into the lumen. And once the wire is in, you, you have to apply forward pressure on the wire while pulling the needle back. And then you can remove the needle over the wire. And while keeping the wired steady in place, you would then pass either a sheep or cattle over the wire into the lumen. And once the shift is in, you can just withdraw the wire all together. And with the shift in city, you have a secure access to the vessels. And this is just like a diagram to illustrate the seldinger technique again. So once again, starting from the top left, you have a needle into the lumen. And then immediately after that, you pass a wire through the needle into the lumen. And then while the wires in, you can withdraw the needle. And usually because the needle is a very small caliber needle, so you need to make a small incision on the skin. Enable for you to pass a bigger catheter through the skin into the lumen. And then you pass a catheter over the wire into the lumen. And once the categories in, you can withdraw the wire and now you have a secure access. And there's two, in terms of like vascular access, there's two main types of puncture. One is called anti great puncture. And the other is called retrograde puncture. And to make this simple, it's basically the direction of the shift or the catheter in relation to the direction of the blood flow. So in this diagram, here we are puncturing the common femoral artery. So it's arterial puncture. So let's look at see first. So on see the direction of the sheath is along with the direction of the blood flow. So fight towards the leg. So it's an anti great puncture because it's with the flow of the blood. Whereas in diagram, a the shift is pointing away from the legs of fact towards the heart. So it's against the blood flow in the artery. So it's a retrograde puncture. So if you imagine if you're puncturing the vein, it's just the other way around. But the basic principle is always the same, it's always in relation with the direction of the blood flow. And this is a picture I took last week uh the intervention radiologist theater in Southampton. So this picture looks a bit busy that lots of things going on here and I'll break it down for you. So right in the middle of the screen here, that's the table where the patient will lie on. So the patient head can either be on this end or it can be on this end. And as you can see here, this bid here, it will allow the table to be moved up or down. And one other movement the table can do is to proof to tip the table so that the patient hub, the patient heads move like towards the uh move up. So affect this way, all the patient heads will move down this way. And then you have like right in the middle, this floral machine. This is what we call a C arm. So the CM can be either one of two, they can be either a ceiling mounted, see um like the one in this picture or they be they can be a floor mounted cm where this bit here instead of flight being attached to the ceiling will be attached to the floor. And then this is the actual X ray machine. So this is the machine that generates the X rays and it will leave the X ray machine pass through the patient hit the detector. And that's how you get the X rays, all the floral image and the c of itself, it's got a few movement. So if you can see this, that's the railing on the ceiling. And this whole machine can either move to this direction or this direction, depending uh which part of the border you want to image. And then this cm itself, it can rotate 360 degrees. And then if I bring attention to this bid here, so the whole thing can be tilted once again, either towards the patient hit or to watch the patient's feet to give you a bit more angulations to sometimes uh open up the images and then hiding in the background there that just like a big screen to show like the live pictures of the X rays and the floral to guide the treatment or the procedure. And then this bit there in the background, there's a pump injector. So usually we figured out with contrast and we can connect it to the catheter or, and it will allow the contrast to be pumped through at a much higher pressure than what like it's humanly possible to achieve by pushing down the contrast in the syringe. And usually that will give you a much better, better uh angiogram. And here you can see there's lots of that tiny little controls that's used by the radiograph for to control either the X rays machine or the C arm as well during the procedure. And I just want to quickly talk through who's usually involved in like I our case. So obviously there will be a consultant or registrars, the first operator. And then depending on the complexity of the case, uh he or she might have either one or two assist them. And in big cases like Eva, it's very common to have to assistant. And obviously you need to have a Scrum nous as well. And once again, depending on the complexity, sometimes you can have up to, to scrub nurses and you will have a radiograph in the room as well. And they would be the one sort of like dealing with control of the C arm and change the setting of the x rays to let you optimize the image that you are taking apart from the scrum nurse, that's going to be other eye on nurses in the room as well. Generally, there will be at least two other one will be in charge of monitoring the patient's vital signs during the procedure. So that's the ops machine there. And the other, I honest would be basically a runner to get sort of like equipment like catheter, different types of wire, shape, stand balloons from like either from the cupboard in the room or sometimes they might have to even go to like a specific cupboard or other rooms to get like very specific equipment for the procedure. Okay. And, and do not forget that slide. The lets you. So when they're actually doing the case, this would be pulled out. So basically, to protect the first operator from excessive radiation. All right. And I thought it would be useful for me to talk to sort of like this slide here because before I went into I are, this is all very confusing to me. So I hopefully I'll be able to make it a bit simpler for you guys to understand so that it would be less confusing for you if you step foot in the I R theater one day. So the diameter of the needle is measured engaged. And the confusing bit is the lower the gauge, the larger than needle. And one good example is if I'm sure we've all been asked to do like Cannulas on patient. A blue Cannula is 22 gauge and the green Cannulas 18 gauge where it makes your heart beat a bit faster when you need to put the green Cannula in a patient. At least that's why I always feel like. So the the kind of like makes sense because the green Canada's 18 gauge is bigger than the blue Cannula 22 gauge. So that's kind of like how I remember and catheter and she if they are measured in French unit so short for either F R or just F and one French is equivalent to one third of a millimeter. Whereas the wire diameter they are measured in interest. So the company used like, oh 18 or oh 35 wire basically just mean there are 0.18 inch in diameter or 0.35 inch. Hopefully, this makes sense. And now I move on to talk about uh the sheep. So on this picture here, right in the middle, the white bed, that's the shift itself. And then the one on the bottom, the pink bit, that's the dilator. So you might notice the dilator is much longer than the shape itself and it has a purpose for that. So to assemble the all come slides of separately like this and for you to assemble, you will need to put the dilator through the ship itself. So that if you imagine when this being put through the sheath, that this tip here would lie somewhere like here. And that's because when you puncture the skin into the vessels, the needle is quite small and the wire is even smaller because in the past through the needle. And then after that, I'm not sure if you remember from the diagram earlier, you need to make a small skin incision before you pass the shift and the tile ator in. And hopefully, what the dilator does is because the tip is quite shop, not sharp, like soft and narrow and gradually go back up to sort of like the at the bigger bit in the middle. So hopefully, that will. So if I create like a tunnel or like a path through the soft tissue into the vessels without causing too much damage. That's the idea of like the dilator. And sometimes when you need to upsize your sheath, you need to put like a bigger dilator to like dilate the track before you can put a bigger shift through the track. Or else you might cause lots of like a bleeding hematoma in the soft tissue or even worse, like a dissect the vessels, right? So 12 in IR is you always flush everything before you use them. So you need to flush the sheath, you need to flush the dilator. And once you assemble your sheath, you can just put the shift through the wire into the vessels and then you can remove the wire after death. And then the shift will provide a secure access and one confusing thing about sheep and cattle, which I'll explain a bit further when I talk about the catheter. So just remember for now the shift French size is the measure of its inner diameter. Okay. And I'll talk about the catheter a bit later and to select the shift size is basically based on what are we trying to do with the procedure. So for example, if we're just doing a diagnostic angiogram, four friendship is more than enough versus if we're doing that, either a sten or angioplasty or ballooning, then we might need either a size five or six French versus an Eva. Then definitely we need at least a size like nine French or even 10. And then, as I mentioned earlier, the shift main function is to provide support and the control access into the lumen where you can exchange different type of wire catheter, etcetera. And depending on the ship of the vessel, they can either be curved or straight. Most of the time we can get away with the straight chief. And this is basically to demonstrate the size of the sheep. They are color coded universally. So you don't have to remember what color is, what size friend she if they should always be clearly written on the packaging anyway. But the more you use themselves on the day to day basis, this will just become like a second nature, right? So now I'll move on to talk about wires. So there's three main properties that determine the function of the wires in ir one is the diameter. And as I briefly touched on earlier at the most commonly time, it is oh 18035. And on the smaller end of the spectrum, we have like the A 14 is like a micro wire or you have like a slightly bigger wire like oh 38 and they have different stiffness as well. So stiffness and stare ability kinds of kind of go like hands in hand because you can't have both stiffness and stare a plate. It's kind of like a cut off between the two of them. So a very stiff wire has very little steri ability as and it's quite difficult to maneuver further wire into like tiny vessels like you want. On the other hand, a floppy wire has excellent stare ability. And then last but not least, the coating of the wire itself is one of the main properties as well. And usually they can come in either hydrophilic or non hydrophilic conversation. So hydrophilic basically just means they like water and they are very useful in the fluid environment like in the blood vessels, they are like less persistent. They're generally quite uh can be quite floppy, they can get to solve like small vessels and one thing to note that they are quite slippery. So be careful not to drop the wire on the floor. But at the same time when they are dry, they can be very sticky. So it's always, always you have to flush like any hydrophilic wire before you stick them into a catheter or a shift. Because if you stick them in when they are dry, they can get stuck to the shift or the cata to. And that, that wouldn't be pleasant and non hydrophilic wire. On the other hand, it's much easier to grip and they usually can provide more resistant or stability. And then that's based on the property. Then there's three basic type of wires, excess wire, they usually are quite short. So, so 5 40 to 60 centimeters and we only use them usually right in the beginning after we puncture the vessels, we put like a short excess wire in. So that's easier for you to remove the wire and put the shift in immediately. And maneuver maneuver wire would be a good example of quite a floppy wire with hydrophilic. And the tip is often like curve and they are used for in to try to get into like tiny vessels. On the other hand, you would have a real wire. So real worry is usually very stiff and they could be either hydrophilic or non hydrophilic. And usually it's sort of like a cut off, it's very stiff, it's stable, but it doesn't have very good like stare ability. But that doesn't matter because all we want is a very stable wire for us to exchange either like a long catheter or do the angioplasty or deployed the stand. So this table looks quite busy, but it's basically nicely demonstrate the three main properties of the wire and lots of different types of wire based on those properties. Also, on this side of the screen, you have the A 18 wire like the one a time in 2035. And then you have either the hydrophilic or non hydrophilic. And then this is like like the stiffness gradient of it. This is like stiff and this is floppy. And the most commonly wire you would tears a flat being talked about in IRM is glidewire or the brand name is called a rumor or a Benson warrior is quite used for an angioplasty. Amplex is use quite a lot of as well. Linda Qu'est and this is just a picture of a through more wire. So they usually come in a sterile packaging like this and the wife is. It's basically in sort of fact, this plastic case over here. So this would be the tip of the wire. And at this end here, this is basically a bunk for you too inside the swinging on. Usually this is how you flush the needle initially. When you take it out from the package, you just feel the string spit like saline, you attach the syringe to this end, you give it a good flush. And when this saline coming out from this end, you know, the wire is flushed and ready to use and all the information you need would be on the packaging as well. So this is straight, it's 035 diameter. The total length of the wire is 150 centimeters and always check for the expiry date as well. And another different type of wire. So this is the Amplex super stiff. So this is the example of a real wire. So once again, all the information should be on the packaging is old 35 time eater and this is a bit longer, 260 centimeters. All right. So I thought would be interesting to show some of the real life pictures from the floor or on how the wire looks like. So this is a femur and that's the inferior pubic ramus. So if you imagine the head of the femur is somewhere around here and this is where they puncture, the CFA. So as a recap, quick recap from previously, this would be an anti bit puncture because that's the tip off the shift. They're like the, the, the bit bits of like a darker bit. So it's like in along with the blood floor in the artery. So that's an anti great puncture and all like the different clips and stuff you can see further down in the media aspect of the time. That's just the previous surgical clip from bypass and like the black fluffy stuff. It's just the calcification in the vessels and obviously, the patient has some peripheral artery disease. That's why he's having this angioplasty. So this would be the wire, what's up? This would be a Benson wire. So they're usually nice and straight and they, the consultant would try to get past the stenosis by using this wire, okay. And this is a different type of wire being used here. So as you can see, you can see the pelvis here and instead of one shift, that's two shifts, so they punctured both of the CFA and this time the shift is in the opposite direction of the blood flow. So this would be a bilateral CF a retrograde puncture and I'm not sure how well is this projecting on the screen. But can you see there is a stand there? So they have already deployed a stand in the left common island artery. And then you can see they put like two wires through the shift into the aorta and I'll just quickly jump back to the previous study. So if you remember sort of like how take the wire here looks compared to this, this over it is a much thinner wire. So this is like a maneuver maneuver where, where they try to get down to the vessel. But now they are deploying the stand, they are going to put the balloons up. So they want a real wear something very stable for them to do the treatment. And now I talk about the catheters. So, so, so both sheep and cattle is they're measuring franchise. Uh yeah, franchise. But prison, I mentioned the shift is the measure of the inner diameter, whereas the catheter is a measure of its outer diameter. And this is because if you imagine you need to pass the catheter. True, the chief and the four French catheter should be able to fit into a four French sheath. So the cata to technically should be slightly smaller than the sheaf. So that's why the cat didn't measure of its outer. Where else the shift is a measure of its inner diameter. I hope that makes sense. And the cat it has lots of function. Some of the function would be injections. So you can inject contrast through it or it could be to deliver embolization, either a cause or glues or ballooning angioplasty, deploying the stand or even retrieving and deploying devices. And one of the most common procedure that we do is IBC future either insertion or remover that's loads of loads of different types of catheter. But I would try to describe a feel based on that different characteristic. Okay. So this is a picture catheter are it's called tail catheter because it ships like a pigtail and picture catheter has lots of side whole here. And so they are quite useful like in this case. So that's the IVC filter that I was talking earlier. So this is a picture catheter in the inferior vena cava and on the outside, this would be connected to the pump injector again. So they would inject the contrast at high pressure to get a very nice venogram because they want to delineate West renal vein. So high pressure contrast coming up from the side holes to pacify the thinner caper very nicely. Because if you imagine without the side whole, if all the contrast would just to come up from like this, it wouldn't be a very nice picture. And then this is just to demonstrate even like uh similar like pictures catheter has lots of like different function. So previously, we see a picture catheter being used in the IV see. But here we are seeing the picture catheter being used to drain a liver abscess. So that's the background like normal liver. That's the big abscess that and this is what the picture category looks like on ultrasound. So previously, let all the side holds like here would be just training or the abscess. Okay. And now this is slightly basically to show there's lots of different types of cattle, uh lots of different type of catheter and I are and they're all slightly different because the shape of the tips is different. And we need like lots of like different ships of catheter because the human anatomical vessels, they all slightly different, they're not all the same. So you need a different ship catheter to try to get into different vessels basically. And then I thought I want to talk a bit more about this Simmons catheter or a Sims cata to their community used to sort of like get access into the cellar access as superior mesenteric artery or inferior mesenteric artery. So this is what the Sims catheter looks like. So it's got this like double curve. So one curve over here and one curve over that. So I can't actually find any pictures of a Sims catheter being you. So you just have to bear with my horrible drawing. So if you imagine this is the abdomen iota and this is your Celia access and this is your S M A. So if you imagine without this seems catheter, it will be almost near impossible for you to pass uh when you approach the CFA to pass a catheter up here and to try to get into this seller axis or S M A at an angle. So that's why they have this type of specific categories seems category. So if you imagine what they do during the process, they from this same category within the AORTA, they push it up past the SM and then they gently put it down. And what they trying to do is hopefully this tip of the catheter are we'll get hinged onto the seller axis. And then when they felt that it's Hench onto either the slice of S M A, they do a quick flush of contrast just to make sure they're in the vessels that they think they are and then they can just pass a wire which will come up like this into the cellar axis when then they can push the catheter into it. So just a few more pictures to illustrate different types of capital, how they use. So in this case, so this is a catheter within the popular artery. So this would be an example of a catheter with n whole rather than site whole like the one in the pigtail catheter because they don't really need the contrast to come out. Like from this end, they just want the contrast to go straight down. And obviously this patient has lots of like stenosis here and has lots of like collateralization. But yeah, this is just a good example to show a catheter with a hole. And this is another different type of catheter. So it's only being used for this specific procedure. So this is a uterine uterine fibroid embolization. So in ill, we try to keep everything as less invasive as possible for the patient because as we all know, the uterus has like blood supply from both the left and right internet, I'll artery. So in order to embolize the uterine fibroid, it would be futile if you just embolize one side because the fibroid will just continue to get blood supply from the other side and continue to grow. So they need to embolize both sides, but they don't really want to puncture both groin and if possible, they would want to just get away with just one puncture. So that's why they have this specific catheter. So it's called a robot uterine catheter. So what they do is they just puncture the right CFA. They will get this catheter or up and over the aortic bifurcation into the other. See a embolize the artery on that end. And then when they are done with that side, they just have to pull back the catheter and then they can do the embolization on the same side where they did the puncture, saving the patient's from a double puncture. And this is just to show a micro Cathy to. So this is quite an interesting case. So the patient had a ct abdomen which shows that she has a pseudo aneurysm in the splenic artery. So if you imagine that's the catheter are sitting in the celiac artery there, that's your common hepatic artery and the G D A going down there. So when they're in the Celia access, they pass a micro catheter through the existing catheter are all right. So imagine like this picture in the middle, it's just a zoom up version of, of the pictures on the left. And now you can see this sort of a smaller catheter coming out from the previous catheter. So that's a microcatheter are and then they did the engine on, on that run and then they can see this aneurysm which then they koi. So just to summarize, we touched on basic vascular anatomy, focusing mainly on the neck vessels and the femoral vessels. I talk about the Seldinger technique, how to gain access both into like vessels or in like a fluid collection or a cavity depending on the procedure you are doing. And I'll show you pictures of what the standard IR theater looks like and all the different components in it. And then I briefly talk about community, you shift wires and catheters in I R. So thank you all for listening. And do you have any questions? Thanks, run for that. That was restful. Any questions? Just put them on the chat and I'll read them out. Mhm. That's smoke. Yeah. It doesn't look like there's any more questions on there. Oh, yeah, we have no questions to silence. Yeah. Uh, well, thanks very much for attending. I'm just going to share the feedback form on there. I thank you again for doing that talk. That was great. It really concentrated on a lot of aspects of vascular in particular, but it's really useful to hear about selling the technique. Definitely. Um We've just want to remind everyone that we've got another talk next week on the fourth of May at seven PM on strokes, come back to me. Um And then we have a series of talks running through from May to June um covering the SAIR say interventional radiology curriculum topics. Uh So make sure you sign up for next week's talk, um and upcoming ones. All right. Thank you, everyone. Have a nice evening. Thanks very much, everyone. Just kind of.