UT Austin now, so we'll go forward. So I have no disclosures. And the first case is a 20-year-old male presents, or has had a recent history of orthotopic liver transplant for acute liver failure, and he's now jaundiced and has elevated LFTs in a cholestatic pattern. He's been compliant to his post-transplant medications, and liver biopsy doesn't show rejection. His vessels are patent on ultrasound, and MRCP demonstrates a main duct obstruction, and he's referred for ERCP for further evaluation. So just one comment on anatomy post-transplant. So there's a duct-to-duct anastomosis between the donor and recipient, and anastomotic strictures can occur. So this is what we're gonna be dealing with. I'm gonna start. I hate to interrupt you already, but I have at least seen two cases where people have done an ERCP, people who have Roux-en-Y anatomy not knowing they have Roux-en-Y anatomy. So for the fellows in the audience, please read the operative note, because it's really, really bad for them to do an ERCP and try to cannulate the bile duct through the native papilla. I'm sure all of you do, but I've seen it at least twice, so at least two different fellows have missed it, including two different attendings. Sorry, go ahead. That's a perfect comment for what I wanted to say next, which is that it's very important to review your imaging before you start any procedure so you know what to expect. So as you can see here, there is a stricture between the donor and recipient bile duct. And so just a few comments. So since we're talking a little bit about technique, the sphincter tone is bowed a little bit here. It's at the 11 or 12 o'clock position. And then the wire is seen passing easily up into the bile duct. One important point is that the endoscopist has unbowed the sphincter tone before passing it into the bile duct, so that doesn't put excessive tension on the bile duct. And now we see that there's contrast in the bile duct, so they're able to cannulate pretty easily. And now the intrahepatic ducts are opacified. So here, what's pointed out is the stricture on the cholangiogram. And so the endoscopist here has estimated the length of the bile duct and the diameter. And one way to do this is to use the duodenoscope as your guide. So the distal diameter is 11.3 millimeters. So if you use that as your guide, you can estimate the length or the diameter of the strictures. Just moving forward a little bit. So again, it's pointed out. I'm gonna pause here to ask the faculty, when you see this, what would your next step be? Would you try to dilate this stricture? Would you proceed to stent placement? If you chose to do stent placement, what kind of a stent would you decide to do and why? Well, the questions probably go in the opposite order, at least in my mind. The decision on dilate or not dilate is based on the decision on what type of stent you're gonna be using. If you're using metal stent, probably no need to dilate. If you're using plastic stent, then you need to dilate. I mean, the main concern is that there is a significant mismatch in between the two sizes of the duct. And importantly, the smaller size is the native duct. So you clearly, you'll have hard time putting multiple stents at the same time. At most, you can probably do one single 10-frame stent. Is that really like a distal duct? Is that the recipient duct that little or is that just underfilled? That's how it looks. I think it's just a size mismatch and a stricture kind of combination. But I guess to Peter's point, I think it's, to me, that duct diameter is contraindicated for a metal stent. You'll get, it'll be very painful and you'll get secondary stricturing when you try to put a metal stent into that size duct. That's, obviously, we all know there's a data out there showing metal stents for liver transplants and how it reduces number of procedures. But there were exclusionary criteria based on duct diameter and generally, it's the donor duct diameter that you worry about of creating a new stricture there. But for me, this is not something metal stent would work. Also, the metal stent paradigm in transplant has come full circle in 20 years. First, we said it's not a good idea. Now, we're saying it may be better. Personally, I think most transplant centers don't like you to put metal stents across their ducts. This is an unusually mismatched donor-recipient case here. I think it all depends on how fresh from the transplant the patient is, how badly jaundiced they are, what your goals are for this patient, and so forth. So I think, in the initial setting, a balloon dilatation and a 10-fin stent would be probably adequate until you regroup. In terms of metal stents and duct caliber, a lot of these stents are relatively malleable and the radial forces are not quite significant. So I think if you need to put it, you'll probably get away with it. There are some smaller caliber stents available now, but I think in the beginning, you'll probably want to be a little more conservative and just get the job done and see where it goes. I think, at a minimum, passing a dilation balloon gives you a dry run to see how a stent would do without really burning any bridges or getting stuck or losing or spending money on a stent. So I think I would start with that, not knowing the degree at which we are from the original. This is not a pediatric patient, right? 20-year-old. Okay, young patient. So that explains a lot. Put contrast in the balloon and look at the anastomosis. See how big the recipient duct looks. At least feel how a dilation balloon feels to go inside of the duct. Does it pass with ease, or is it really hard to even get that in? Then you're gonna have a hard time getting a stent. Question with dilation is how fresh from the transplant is everyone comfortable with dilation? That's where I brought up the timing. I think there is no data on that, I think, but we generally will say about four weeks is reasonable, Peter. What do you think? That's what we use in our center, four weeks. Before that, we'll avoid dilation. It's obviously purely empirical. But, I mean, in this case, guys, I'll be hard-pressed to say that there is a stricture there because the duct mismatch is so significant. What I'll personally do, I'll just stick a 10-franc stent and see whether the patient's LFTs will improve. And if they not, look for alternative explanation, do a liver biopsy or whatever. Yeah, which is why going conservative is better. Also, there's another problem with this phalangeogram, this anatomy. I don't like this. And this is unfortunately the predominant anatomy in post-transplant patients. And can any of the fellows, who's on mark there? Who's the person who gets called every time? All the women, because the men are. So what do you think? Do you like this phalangeogram? Are you happy to see it? Well, at Mayo Clinic Arizona, about 90% of the cases that I've seen so far have been post-transplant. And sometimes we do it as early as two weeks after the surgery. What's the problem with the phalangeogram? The left duct is not convincingly visible. Well, let's look at the donor phalangeogram there. The donor, I'm giving you a hint. Where, the right? There's a 90 degree left turn. So, what will happen to a 10 front stent as it navigates that turn? So you have to factor that in. You have to either go well above that turn or stay well below that turn. Once you engage that turn, the stent's gonna fight the duct and likely get pushed down into the duodenum and then you're looking at a lateral wall situation. But yeah, anyway, so that's just a nuance related to ductal anatomy and plastic stenting. Can I? Dr. Eisenberg had a comment as well. Peter has a comment. Vivek actually stole my thunder about the phalangeogram but I have another question. So, I'm sure that our institution is in the minority but all of our transplant surgeons, for whatever reason, have decided to place valerian stents during the transplant process and I'm just curious how many other institutions actually have their transplant surgeons put in a stent that they want us to take out two, three months later? We do not. We don't. We don't because they need a reason to blame us. There is a stent, take it out. There is no stent to any of them. I think it's kind of interesting how some of the practices in transplant are varied in this situation and it seems like our transplant surgeons are maybe not as confident about doing their duct-to-duct anastomosis and that's the reason why they're putting in stents all the time. And so, we don't know what the outcomes are for these patients because maybe that would prevent a lot of the situations from occurring when they do put these stents in and I'm just curious. This is actually fertile research grounds, right? So, as you're progressing through endoscopy training, these are the kinds of things that you should identify as potential research projects to get interested in and if you're gonna be somebody who's interested in doing endoscopy, there are a million questions that come up every day and you're not gonna have a chance to answer all of those. So, pick one every night to research, to look up and this is how you're going to learn. This is how you're gonna learn the differences in techniques, the differences in diagnosis and the differences in treatment. It's very similar to what the post-vipple surgeons used to put pancreatic stents across the pancreatic or jejunostomy. There's a few still out there in the country. I saw a patient from Maine recently that had one. Similar concept, prevent strictures, prevent fibrosis and as we all know, most people's PJs will still nose over time. So, very good point. The case is moving on. So, in this case, they elected to place a seven French five centimeter biliary stent and just a couple of things on stent placement is that and they chose a plastic stent. So, there's an introducer part, which was the black part that you saw with three or four radio opaque markers. So, you can use that to guide where you're gonna place your stent and then you push that over the introducer and now that I'm a year out of training, I've had to teach my techs how to place biliary stents. So, remember the tech side of what you're doing as well and listen to what your attendings are telling the techs because you will have to do that in your practice too. And now we're seeing a bile leak from the intrahepatic duct. So, what are ways fluoroscopically to tell if it's a small or a large bile leak? High pressure cholangiogram. Yes, so, yeah and they didn't end up doing this here because it kind of showed up later but it didn't show up immediately and also the intrahepatic ducts were able to be opacified. So, that suggests that it's a small leak. And so, now the endoscopist is running into some technical difficulty in placing the stent. So, maybe they should have dilated to begin with. But what would you do, faculty, at this point? Would you take it out and then dilate and then try again? You know, what would you do? And what's the introducer size for a metal stent? Would that work? I would just say that where you're getting stuck would suggest to me that it's the duct size, not the anastomosis, but it's hard for me to tell on the cholangiogram because you can't have more than three centimeters of stent in right now. Right. So, I'm surprised but I usually just fight it. I go to long position, short position over and over again, make sure I don't get too much stent out because I lose my pushing force. And I mean, I may be destroying the pancreas somehow by all the pressure I'm putting but there's no point to me of trying to come out if you have a chance to still get this in because I'm not sure what else you'll do to help your situation but that's my opinion. So, it's a good idea when you're going in with the tome, how does that feel? I mean, if it's tight with the five French would, you know, really think about dilating first because, you know, to Raj's point, like, if it gets stuck in the channel, you got to come out, just go, you got to recant, I mean, it's a major pain in the neck and we've all been there where we're like, shit, I should have, you know. So, if you're feeling a little resistance, think about dilating with plasma. Can I ask a, so it might be a silly question, is there a reason like a sphincterotomy? I don't think a sphincterotomy is performed, at least not from what I saw in the video, I was just curious. That's a good question, do you always need to perform a sphincterotomy? I think for the purposes of this, you don't have to, you're just trying to cross that stricture. Or the mismatch, okay. And, you know, you're at risk of having the stent migrate too if you do a sphincterotomy, so. Yeah, I will say that I'm one of the few people who doesn't do sphincterotomy for stent placement, but there's pretty good data to show that your pancreatitis rate goes up if you place a stent without a sphincterotomy, so I've tried to adjust my practice and I only don't do it when I think the coagulopathy now, right after a transplant. So, there is, I don't know if, I can't quote data, I just know that studies exist, they can be like levels eight evidence for all I know, I just know a study exists that shows that stent placement without a sphincterotomy is an independent risk factor for pancreatitis. You're correct, and the other thing to factor in as far as the decision of sphincterotomy versus no sphincterotomy, presuming that there is no major coagulopathies, I can assure you this will be not the last TRCP this patient will get. So, might as well do the sphincterotomy, be done with it, and because you'll be there multiple times. Yeah, so I just don't do it right after transplant when there's still the portal hypertension. No, yeah, that makes sense. To delay it to the next TRCP. Yeah. Sometimes with this size of the duct, you might not feel comfortable dilating with the gluon because the smallest gluon you have is four billion, that's 12 French. So, I use a lot of passage dilators because they come in a lot of sizes. You can start with like three French, go up to all the way to 12 French. So, four to seven French dilators if you're trying to get a seven French stent in. Was it an incorrect observation that it felt like there was a lot of introducer? You know, how much introducer do people usually leave at the end of their stents? And, you know, was maybe shortening your introducer, would that have helped with getting the stent in? Yeah, because remember, when you see the marker, there's a couple centimeters of introducer, and if it's way in the liver, you will never get that stent in. So, that's the important thing as you're tech and you're teaching your tech. They can't let that introducer go far in the liver. You can push all you want, and you're never going to get it up. And maybe they weren't giving enough tension on the introducer part, right? Yeah. No, I agree. It did look like a lot. And there are different systems. I mean, this is a seven French. We don't have, we use the Cook Oasis, and we don't have seven French. We do it over a wire, but, so there are different systems. I think the other challenging aspect or anatomy of this is sort of what we talked about with the 90-degree turn, and thinking about that with your introducer. So, I like that you picked a short stent so that you don't have to deal with that above in the donor liver, and something that you have to think about with how far you're going to put that introducer. So, I like the idea that you keep it short so that you do have a little bit more control and try to have it where it's not near that turn. Would anybody in the group place double pigtail stents to navigate that turn? Because then you would have a pigtail up in the liver hooking into that 90-degree turn. So, food for thought. It is. This is some food for thought. This picture is much further below that, so I don't know that you'd need. Yeah, I don't think you'd have to go above the turn, but I think a double pigtail, the double pigtails for the fellows are hard when you have a really dilated extrapedic duct, because it'll pigtail in the extrapedic duct. But in this very narrow caliber extrapedic duct, it's gonna go up like a regular seven French would. And as soon as it gets to the dilated area, then it'll curl. And so, it's a nice thing to use for this type of case. But I think a straight seven French like this is gonna work too. Also remember, the double pigtail, the length is not the entire stent. The length is the middle portion before either pigtail starts. That's why it almost triples pigtails. So, for the fellows. By the time you're done with it. On the technical aspect of when pushing the stent, is a lot of times you need to stay very short when you have a stricture. And I know Raj was talking about going short, going long. But initially, when you are learning how to put these stents in, one of the problems is when you face that stricture, the stricture is gonna push back on you. And if you keep pushing the stent out, it's gonna bow out in the lumen. And once it starts bowing out, you're gonna potentially lose access or lose that pushing capability. Especially when dealing with stents that do not come with an introducer. If you're pushing over a wire, and that bow forms, it's done. So you need to stay short. Maintain the vector, the direction of where you're pushing, the same direction as you're bowed out to increase your chance of pushing it through. If I could just kind of query the faculty. My practice with post-transplant strictures and sphincterotomies is that I'm more conservative. I'll cut a complete sphincterotomy, but I don't always go up to the duodenal reflection. Just because I, especially in a young patient who's just had surgery, I'm worried about the long-term effects of gastric juices refluxing up to that anastomosis. Does anyone else kind of modify their sphincterotomy practice based on this in this clinical setting? I don't for transplant, I do for PSC. It's a very small sphincterotomy because, again, it's a two-way street. So, yes, bile can come in, but you can also get bacterial access into the belly, which can cause recurrent cholangitis. Jennifer, it depends on what type of stenting you're gonna be using. Using multiple plastics, you need space for those, so you need to go fairly large with your sphincterotomy. If you do metal, as long as you have separated the pancreatic orifice and the metal stem doesn't compress it, you're okay. So, I will call it adequate sphincterotomy. And that's kind of what I aim for, but I don't, I try to avoid the gaping hole that we sometimes see. Yeah, probably a little bit less than for 20-millimeter CBD stone. I think for those cases, I don't really change my practice, but I think you're really just limited by what the size of the duct is, right? So, you really just, I think that really dictates how you can cut, and that's all that really is a hard line there. All right, awesome. Okay, I think we'll move on to the next.

liver transplant

MRCP

ERCP

stent placement

bile ducts

bile leak