He is an associate professor at the Division of Gastroenterology and Hepatology at the University of California at San Francisco. He is the director of advanced endoscopy at that institution and has expertise and is well known for his expertise in endoscopic ultrasound and ERCP, and he will talk to us about tricks and tips for biliary cannulation. So without further ado, Mustafa. So as stated, I'll talk about biliary sphinctrotomy including PRECUT, and this is a nice follow-up to an excellent presentation by Brian. So here are my disclosures. I guess there are three main points that I would like to discuss in this presentation. Number one, safety and success are the key outcomes more so than selective biliary cannulation. While in a biliary case, our goal is to get selectively into the bile duct at the expense of trying consistently to get into the bile duct at the expense of failing is not worth it. Oftentimes, as was pointed out in the last talk, it's better to try a different approach. Knowledge of various cannulation and access techniques is critical for anybody doing ERCP, and as stated earlier, there should be a willingness to adapt based on the situation and also knowing when to stop so that we don't cause harm. And that leads to the point that we need to know what the risk factors are pre-procedure as well as inter-procedurally, understand the adverse events as we try different approaches and know how to deal with these. So approaches to biliary access, as was pointed out, traditionally, it's been standard cannulation with a synchrotome or a cannula with contrast and or wire. And then when that was not successful, PRECUT access techniques were used. If those failed, choices were to refer to another center, retry, or refer to radiology. As was pointed out in the last talk, a nice technique that has evolved over the last sort of 15 years or so is if you have access to the bile duct, to obtain the pancreatic duct, to take advantage of that access, push the pancreatic duct downwards, placing a pancreatic stent in this setting has been shown to reduce the risk of pancreatitis. And then utilizing that approach to cannulate the bile duct and subsequently be able to perform the biliary maneuver as needed. The choice of the pancreatic stent may be such that it can be a self-ejecting stent so the patient may not necessarily need a follow-up procedure, however, the patient should have follow-up to ensure that the stent has passed even with an x-ray. So how have we sort of evolved over time? I think because of these newer techniques, there is a tendency by some providers to go towards the double wire technique with pancreatic duct access. And if that doesn't work, to move towards PRECUT access techniques, whereas I believe my sense in talking and discussing with various sort of colleagues and friends around the globe is that there seems to be a split, some people still prefer to go to PRECUT access techniques. And as was pointed out, it really is optimizing and knowing the data to see which approach is the best. So before we get into PRECUT techniques, because part of the discussion about this topic is standard biliary sphincrotomy, I do want to sort of bring up some points. Generally speaking, the bile duct will run up the middle of the mound. So while our cannulation may not necessarily sort of orient us in the same direction as we start off, the fact remains that the bile duct will run up the middle of this mound. So when we're doing a sphincrotomy, we want to try and aim to cut up the middle. In this video, you can see the mound, you can see where the middle is. Once cannulation is achieved, a sphincrotomy is started. However, you can see that the sphincrotome is misdirected towards the right side. In that setting, the sphincrotome is sort of pulled back, and then the sphincrotomy is reoriented towards the direction of the middle of the mound, thus sort of ensuring that we minimize the risk of a sphincrotomy-related perforation. And there is the final sphincrotome. You can see the wire going towards the initial misdirected cut. Biliary sphincrotomy concentrations are the type of current we use, pure versus blended. Pure cut current means that there's no coagulation involved, and that is associated with less thermal injury with increased risk of bleeding, and the blended current will lead to less bleeding and more coagulation. Continuous versus intermittent, some people prefer to cut continuously, others will do intermittently, and it also may depend on the size of the papilla. Generally speaking, with continuous currents, we will get more coagulated effect. And consideration that has to be kept in mind is tension or bowing or flexing the sphincrotome can lead to tension in a zipper cut, so uncontrolled cutting, which can lead to a perforation. In this video, you can see there's a lot of thermal injury going on. You can actually see the smoke sort of coming from the burning tissue. So the cut has been stopped, the tension on the sphincrotome has been increased, and now there is less burning and a cleaner cut. So having bow on the sphincrotome helps reduce some of the thermal injury because there isn't much movement otherwise, and we're just coagulating tissue. The extent of the sphincrotome is always a question that comes up with trainees, and the answer is it's really based on the indication and the size of the papilla. There will be a separate talk on this on large biolog stones, but generally speaking, if we think we've reached maximal sort of sphincrotome length, then it's better to stop and perform wound dilation or sphinctroplasty rather than continuing and creating a perforation. One has to be cautious with small, flat papillas, stenotic papillas, in quotes, sphinctroverty dysfunction. These patients tend to be at a higher risk of complications, including bleeding and perforation. And generally speaking, the bleeding risk, which I'll get into later in the talk, is more a feature of cutting versus not, as opposed to the size of the sphincrotome. So moving on to the real sort of issue here, which is pre-cut sphincrotome techniques. This is a nice sort of summary slash sort of figure of the different techniques by my mentor, one of my mentors, Dr. Martin Freeman, who I had the pleasure of working as well as training with, and he describes these nicely as sort of four different techniques, three needle knife-based approaches, one sphincrotome-based approach. Two of these are with pancreatic duct access and two without. And the whole idea is based on the indication, one can decide which approach to take. And I'll just go through these one by one. So needle knife at the orifice implies that the needle knife is actually extended to the papillary orifice, and then the cut is made superiorly towards the bile duct in order to obtain the access. This is a good technique for fellows or trainees, especially in the setting, specifically, I guess I would say in the setting of an impacted stone, because you have a nice bulging papilla, and that can be used to then practice needle knife over the stone and get the initial stone out using a needle knife technique. This may be a good way to sort of get comfortable with this technique. And once that has been done, deeper cannulation is achieved, the sphincrotomy subsequently extended. And in this case, additional stones are removed so that the procedure can be completed. And at the end of the procedure, there's large orifice and multiple stones that have been removed. Here, when you don't have a stone, essentially the concept, again, is to aim up the middle of the sphincter and unroof the sphincter, identify the white mound of the sphincter and then gently probe it to achieve cannulation. This is a video of a difficult cannulation where it was a very generous sphincter mound where needle knife was performed at the orifice. And again, the concept remains the same to stabilize the needle knife rather than moving it around. You stabilize it in the elevator and the scope and then coming up the middle of the mound. And the point here is, as we do this, it can be challenging to know exactly sometimes where the bigger sphincter is. However, it's generally going to be deeper, not necessarily more superior. And if we keep cutting superior, that's where the risk of perforation is. So if we suspect that the mound is in the middle here and the orifice is not very clear, we can continue the cut in that direction and then subsequently probe it, in this case with a three-frenched cannula, and achieve deeper cannulation. So this technique involves starting at the orifice. Now what's been described subsequently and has been shown to be perhaps or definitively safer is actually to avoid the orifice and start either above the orifice or the top of the mound and cutting in either upwards towards the bile that are coming from the top down towards the orifice. And that would be a needle-knife prefixed histelotomy. So cutting up or cutting down, but not at the level of the orifice. In this video, going upwards, the papilla sphincter muscle is exposed and cut further and subsequently cannulated. And in the second video, where there's a peripterodiverticulum, the mound of the biliary sphincter is identified, and this is a top-down approach in layers, unsheathing the sphincter muscle and subsequently, once biliary access appears to have been achieved, probing the area and accomplishing cannulation. An extension of this would be if pancreatic access has been accomplished to place a pancreatic stent to orient ourselves and subsequently perform a needle-knife sphincterotomy. Here the pancreatic stent has been placed, and now the orientation of the cut again is towards the middle of the mound to expose the biliary orifice and removal of the stone. In the second video, there wasn't a stone, but the same principle has been applied, and in layers the sphincterotomy is performed and subsequently cannulation can be achieved. And the fourth technique would be to actually achieve pancreatic cannulation using the sphincterotomy and orienting the sphincterotome towards the bile duct to create a sphincterotomy, either expose bile itself or make the orifice larger to then perhaps try a second wire using a double-wire technique, as was done in this case in a patient with a biliary restrictor from chronic pancreatitis. This biliary sphincterotomy can then be extended and treatment offered as needed. So those are the four main techniques. Now, before I get into sort of the depths of how one should approach these, I think it's important for us to be aware of the adverse events and risk factors associated with sphincterotomy in general, and especially with these pre-cut techniques. And of course, the ones that we know are the most concerning are pancreatitis, bleeding, and perforation. These are all cases that I have been involved in, and it's always easier to show cases when you're not the person who has actually caused the damage. So I will admit, and I will show you some cases where I've had adverse events. But this is a post-GICP pancreatitis in a patient, necrotizing pancreatitis in a patient with an anpillary cancer, whose surgery was delayed by at least six to eight months. At the time of surgery, he had metastatic cancer. This patient, I'll show you a video of, with a sphincterotomy bleed from a needle knife. And this is a sphincterotomy-related perforation in a lady with pancreatic cancer, who again had delayed his surgery. And subsequently, while she may have had advanced disease, at the time of surgery, she certainly had a metastatic disease. So starting with pancreatitis, Dr. Freeman and I have written a couple of editorials on what we described with the four Ps. Subsequently, the fifth one has come around. But those are the patient-related factors, procedural, pharmacologic, pancreatic stents, and periprocedural fluids. I think all of us should figure out, A, a way to recognize the risk factors, and B, be aware of them. I find that oftentimes it's a lack of knowledge of what the risk factors are that is the issue. And if we specifically focus on the procedural aspect for the purposes of this talk, difficult cannulation, which is usually, by the time we're employing a pre-cut technique, we're describing it as a difficult cannulation, pancreatic guidewire passage, pancreatic duct injection, pre-cut sphincrotomy, and pancreatic sphincrotomy. So essentially, any time it's difficult or we have touched or manipulated the pancreas, the risk of pancreatitis goes up. In this large series from China, the three of the procedure-related factors were cannulation time greater than 10 minutes, needle knife pre-cut, and greater than one pass into the pancreas. On the flip side, if the pancreatic duct has been accessed, and oftentimes this is in experienced hands, in the setting of repeated attempts, it may be wiser and safer to actually leave a stent in the pancreatic duct, and if a pre-cut technique is to be employed, then to do it after placing the stent. Because removing the stent intra-procedurally or not placing the stent has been shown to be associated with an increased risk of pancreatitis. The discussion regarding pancreatitis is a bit nuanced, because in experienced hands, an early transition to pre-cut, the risk of pancreatitis may not be as high. This is not to say that all pre-cut leads to pancreatitis. At the same time, pancreatitis risk does go up, especially in experienced hands, and with delay in pursuing pre-cut. The second risk factor that we need to talk, or complication, or advanced event we need to discuss is bleeding. Of course, anticoagulation is a big one, core morbidities, but when we talk specifically about procedure-related events, intra-procedural bleeding, low endoscopistic experience, and unsuccessful cannulation with a pre-cut have all been shown to be associated with bleeding. This is a patient with a sphincterotomy-related bleeding. One of my own cases, a 12-year-old female with anomalous pancreatic bleeding junction and a type of cortical cyst presenting with cholangitis in the bile duct stone. She had a sphincterotomy, stone removal, stent placement. The surgeons also wanted to know the anatomy with respect to planning for surgery. She subsequently developed bleeding, some hemodynamic instability, and so the procedure was repeated. At this point, a vessel was identified on the lateral wall of the sphincterotomy site, which was treated with ECLIP. When we review the video afterwards, this looks like it's extremely slow. The point there was to try and ensure that ECLIP was placed appropriately on the vessel and then subsequently deployed to treat the vessel. Now, of course, the vessel oftentimes is a traversing vessel, so there has to be a second part to it on the other side. In this case, the patient had an anomalous pancreatic bleeding junction. Typically, the pancreatic orifice will be down to the left, so one has to be careful with any aggressive maneuvers here, but in this case, knowing that the pancreatic orifice was inside, coagulation was applied to the lateral, the middle wall of the vessel to try and minimize the risk of bleeding from the second side. Fortunately, she did well and subsequently ended up having surgery for her cortical cyst. And this is a case of a patient who has a history of a liver transplant with a ductal duct anastomosis with a stricture who was referred for ERCP, then by an experienced provider, resulting in an unsuccessful liver cannulation, as shown in the fluoroscopy images. It's an awkward position. Pancreatic duct access was accomplished and contrast injected. A freehand needle knife at the orifice was attempted with a plan to return in 48 hours. The patient subsequently sort of overnight developed bleeding with hemodynamic instability requiring transfusion. Now, the challenge here is that we don't have biliary access, and we also don't know the depth of the cut. So this was a hoping for the best kind of approach as we go in, but with some careful sort of maneuvering with a smaller sphincter tone and a small overnight wire with gentle probing, biliary cannulation was accomplished. As you can see, the scope is in an awkward long position, and there is a stricture and then anastomosis. So fortunately, the technology for us has evolved in today's day and age so that we have tools at our disposal. The stricture was dilated with a balloon to facilitate stent placement, and while we had the balloon out there, we placed a balloon dilated at the orifice too. And this was subsequently treated with a fully covered metal biliary stent that traversed the level of the stricture as well as the sphincterotomy site to tap on the bleeding. In this case, the area of the sphincterotomy was also treated just using a tapered cannula with epinephrine, simply because we could and we were there. I think it's a belt and suspenders approach, but it may help reduce risk of bleeding. Interprocedurally, when there is mild oozing, this is a nice technique to tampon out the area of bleeding. And then the final big one is perforation. Any sphincterotomy, of course, has a risk of perforation, and pre-cut sphincterotomy certainly is not sort of excluded from that. There are a couple of cases that actually I was the provider for ERCP with recurrent acute pancreatitis in the setting of a small stenotic papilla, a double wire access, a PD stent, not shown here, but was placed, and then a biliru sphincterotomy was performed. As you can see subsequent, so the patient actually developed post-ERCP pancreatitis, was hospitalized for about a week, subsequently discharged, and three days later presented to a local hospital with pain, fever, signs of infection, and on CT scan, there's clearly a retrocardial perforation with extension towards the pelvis. She was transferred back to our institution. At this point, a repeat ERCP was performed, and this was treated with a fully covered model stent, which if identified either relatively sort of early or intraprocedurally is a very sort of nice and safe approach nowadays is to consider placing a fully covered model stent to completely seal the perforation. This is a second patient with an elderly lady with recurrent acute pancreatitis, non-ductal dilation with a stenotic papilla in whom pancreatic RFS access was initially accomplished, and because of the stenotic smaller papilla, a traction pancreatic sphincterotomy was performed in the hopes of achieving biliru access. Unfortunately, during the course of the procedure, it became clear to me that there was free air, so the first step was to place a pancreatic stent to ensure that we at least drained her pancreas, and subsequently, in this setting, we sort of stepped it up to an ERSC-aided access to the biliru, to the bioliquid, because of the synchrotomy, the biliru RFS was just not being able to be visualized. The sphincterotomy was performed, and the biliru access, once accomplished, was treated with a fully covered model stent. So how do we put all this together? Well, I think this has been shown, including by Dr. Reddy and colleagues, that pre-cut sphincterotomy, when done early and in experienced hands, is better than repeated attempts that can lead to damage. So of all the different approaches, what can we summarize based on some of the data? Needle knife at the RFS may be, and likely is, the higher risk of all the techniques, simply because there isn't any orientation towards the pancreas. It's literally a freehand technique, and there is a risk of all of the three complications. A fistulotomy, whether it's top-down or bottom-up, may reduce the risk of pancreatitis, because we are avoiding the pancreatic orifice. This is especially helpful for a bulging papilla, where we have a larger target that we can aim for. If pancreatic duct access has been accomplished, a pancreatic duct stent placement has been shown to reduce the risk of pancreatitis, and is the preferred approach. And subsequently, the sphincterotomy can then be performed. And then, finally, if a traction sphincterotomy is to be considered, this may be something to be done in smaller papillae, or in the setting of a diverticulum. Again, at least in my experience and my preference, if PD access has been accomplished, then placing a PD stent first, and then performing the sphincterotomy, sorry, then aiming for cutting the sphincter, placing a PD stent, and then targeting the pancreatic duct. So where do we stand currently? I think, as stated in the previous talk, it has to be optimized to the experience and comfort level of the provider. I think there continues to be a split on early needle knife slash pre-cut techniques versus attempting double-wire techniques. I think the key point here is safety and experience. And if, in an experienced hands, a pancreatic duct is achieved, is accessed, then there should be a tendency to leave a pancreatic stent. I will say that I follow more of the right side of the algorithm, where I go down towards pancreatic access, pancreatic stenting, and then make my next move. But I will acknowledge that there are those who will go straight to a pre-cut technique. But I think we've moved on, and I think this will be highlighted in this sort of seminar, that if either of those is not successful, we do have EUS-guided access techniques that we can refer, move on to. And always remember, we all have to remember that, you know, on that day, if it doesn't work out, safety first. We can always refer to a colleague, call in help if there's somebody around, retry on a different day. And there are some settings where sometimes it's just okay if we don't do it, and somebody else does, like, interventional radiology. So I'll finish with the same three points that I started with. To summarize, safety and success are key outcomes. As much as we want to have selectable recurrence, and sometimes that's just not feasible, and that is okay. The key thing is not to do harm, and to accomplish the role that needs to be accomplished. We all need to have a knowledge of the different cancellation and access techniques, and have the willingness to sort of adapt based on the current circumstances, and know when to stop. And then finally, knowledge of known risk factors for complications, and recognition of adverse events during the procedure, and then being able to manage these successfully. With that, I'll conclude, and thank you again for the opportunity.

biliary cannulation

ERCP procedures

safety

success

cannulation techniques

complications management