So for the next roughly 30 minutes we're going to be talking about cholangioscopy and pancreatoscopy. Now as a caveat, these are really advanced techniques that have gotten easier and easier to use. And what we've seen is the volume of these cases have increased over time. So as was mentioned earlier, the utilization of cholangioscopy may have been much lower 10 years ago. Why was that? Well, difficulty with setup, difficulty with using the devices. They weren't as slick and easy to use. But these still represent a very small percentage of the types of interventions that we use for ERCP. As was mentioned, the number of ERCPs is somewhere between 600,000 and 700,000 a year in the U.S. The fraction of those that use cholangioscopy may be at best 1 in 20 to 1 in 50. I don't know. I'm just ballpark guessing, right? So there is an opportunity there to increase that rate, and in some places maybe even less than that, maybe less than 1 in 100. And so there's an opportunity to increase this modality. And so I want to show you some of the historical aspects of things and where we're going. So we're going to review the devices that are currently on the market. We're going to understand the indications for these interventions, discuss limitations, and then adverse events. So cholangiopancreatoscopy devices, now we actually have two that we have in the U.S. market that we have been using. And unfortunately, this market's been dominated by one company, and so I think everyone synonymously applies cholangioscopy with Spyglass. So it's just easier to say Spyglass than cholangioscopy. No one's going to really say that. But these involve a processor and then a disposable scope that goes along with these. Now we have competitors, and outside of the U.S., there's many more processors and competitors in Asia. So here, I just wanted to show this setup, and let me see if I can click on this. It's a link to a YouTube video, so it's nothing great. But it does go over kind of what are the steps that are required for setting up. So this is just the most commonly used one. You have to unbox the device, and as Dr. Kara mentioned, you know, he gets less complaints from his staff. I still get complaints from my staff when I'm setting this up when it's unanticipated. Even though it's pretty easy to set up as you can see here, it does deviate. You have to get the cart in the room. You have to have it set up, flushed, primed. You have to reroute the connections of the monitors that you're routing to it. And so you're basically, a lot of things have to happen. And that's why I like to have more than two people in the room to kind of just get things going quickly. Because when I want to use this device, I like to use it quickly. So it's not only taking it out, flushing the channels, attaching the appropriate instruments, but then also attaching it to the actual scope, processors, and then routing the imaging. So if you're going to be supporting this type of intervention in the future, you're going to be seeing the nurses and techs struggle with okay, I need to get this now on monitor 1, monitor 2, and you know, how to do that. And that's something that's beyond your control. But just to be aware of what are some of the things that people are dealing with when they're setting these up. Now what are the indications? I want to specifically speak about cholangioscopy for the first few minutes and then we'll switch to pancreatoscopy for the last few minutes. So the indications, the most common ones are for stone removal and stricture evaluation. Okay. These are the two most common things, and these are some of the most common indications for ERCP in general. Also for wire placement in unique circumstances like trying to place a wire into the gallbladder when you need to drain a gallbladder for cholecystitis. And to direct and assess therapy, and we'll talk about that. Now cholangioscopy for biliary stones is really reserved for the difficult bile duct stones. Now if you look at all stones, all comers, you're not going to use this modality for stones that are the most common garden variety, you know, 5 millimeter stone in the common bile duct. That's not really kind of the use of cholangioscopy. But what is very useful for is for large stones, and we usually use a cut point of 15 millimeters or larger. Failed prior attempts at clearance of stones. So you try to get a stone out, couldn't get it, or even during that same session. Impacted stones that are really wedged in, they're hard to pull out with a balloon or a basket. And then multiple or numerous stones. I like to think of using cholangioscopy in this case to make sure that I got everything out. Sometimes there's so many stones there, you can't tell if you've gotten everything or not, and so cholangioscopy can be helpful. Specifically in those in the intrapadic duct location, so here's a diagram here. So when we're talking about garden variety stones, these are stones here in the common bile duct. So they're sitting in the lower duct, as Dr. Chahal just mentioned, you do a sphincterotomy, you put a balloon or a basket, and you pull these stones out. Well, when they're stones wedged way up into these ducts here above the bifurcation, it's often very difficult for us to identify and visualize. And so having a tool that allows us to directly visualize these stones is helpful. And then also for stones that are located above a structure where it may be difficult to pull through because there's a narrowing down below. So this is an example of an intrapadic bile duct stone. So these are stones that have been wedged in, and you can see the ducts above it. They're not huge, but the location is just making it difficult to remove them and to find out how many stones there are. And in this technique, we're actually using a basket, which is through the cholangioscope. And then you can see, initially I thought it was just one, and then all of a sudden you see a couple more small stones behind it. And yes, these are not large stones, but having this technique to identify, isolate, and then to remove the stones is actually very helpful. This is somewhat unedited. I wanted to show you kind of what we struggle with trying to get a basket around. The directionality, the torque that we often will require to wrap around these stones can be challenging. And then you can see I'm pulling back below some of these other ducts that are branching off and then pulling this out of the patient. Now for large bile duct stones, I have to say, and this question was asked before, I do think large papillary balloon dilation has revolutionized the management of large stones. But this is, again, as mentioned, this is a dilation after sphincterotomy. So we do a limited sphincterotomy. The bile duct has to be dilated. You cannot dilate the distal bile duct to 15 or 18 millimeters when it's only 5 millimeters. So if there's a stricture down below, it doesn't work. You have to have a big duct and a big stone. I actually used this yesterday, and I was trying to get the video from the case yesterday because it's much nicer than this one. But you can see after we did the balloon dilation, there's a big gaping opening now. Then we can go in, and you can see all these stone fragments that were coming out as we kind of fragmented the stone, inadvertently trying to pull them out. And you can see all these stone fragments that are there. So this technique has really revolutionized stones. But in those limitations where you cannot dilate the duct because the duct is small or because there's a narrowing and the distal duct is either 4 or 5 millimeters, the stone is up in the common hepatic duct, or you just have a really giant stone that's not going to come out no matter what, there are options for us. So these are mechanical lithotripsy, but for cholangioscopy-directed lithotripsy, which is breaking down the stone, there's electrohydraulic and laser lithotripsy. And so in this video, here's a stone that's pretty big. We're taking a look at it. And one of the limitations with electrohydraulic lithotripsy is you have to have saline. You need to have a medium to conduct this. And so we use saline. We irrigate that as we're putting the probe adjacent to it, and then we're firing off. And you see this screen, what happens when you fire and blast the stone. You kind of lose visualization momentarily. But then you dig and dig, and then you hopefully fracture the stone into pieces. If you touch that tip to the stone, you just bury a hole in the stone. You actually have to be just a few millimeters away from the stone and let the saline conduct and then allow for the lithotripsy to happen. You can see now we've fragmented this stone into multiple pieces that are still very big, but they're now manageable to extract. So this is the process of how to break down stones. In a large multinational study, mostly in countries in Asia, they found that for difficult biliary stones as I defined on the prior slide, success in a single session was 80%. So these are patients who have gotten repetitive ERCPs, and now you're able to clear it all in one setting. The issue is you have to know that going into the case, and you have to have the time to do that going into the case. Sometimes you've got very limited time, you've got 14, 15 cases, and you don't have the bandwidth scheduled. It was misscheduled for a 30-minute case. So you need to have time to do these. These are not cases that can just be done in 20 minutes. Now switching gears to biliary strictures, there's a big opportunity for biliary stricture evaluation and assessment in my personal opinion. The reason being brush cytology, what we just do is basically a pipette brush kind of that goes back and forth, has a sensitivity anywhere from 8% to 43% based on the definitions. But the specificity is really good, meaning if you have a cancer diagnosis, it's really cancer. Sensitivity means that there is a cancer there, but you're only able to diagnose it 8% to 43% of the time when there's actually a patient with cancer. And so if you loosen the definitions, okay, if someone has suspicious cells, then you can increase that sensitivity. What are the challenges? Well you need to find the desired target. You can see here we're in an ERCP and the stricture is here on a branch off. So just to get a wire across, a brush across is difficult. These tumors can be very dense in stroma. So when you brush it they get mostly kind of loose, bland looking cells and not cancer cells. So it's hard for the cytologist to actually get a diagnosis. And there's a lot of variability with interpretation. So how do you improve diagnostic accuracy? Well there's better brushes. You do it, you brush more. So you do either 30 brushes across the stricture or you can do multiple brushes of the same area and that has shown to increase the diagnostic accuracy. And you can see here, but with 30 brushes we're saying woohoo, 57% of the time we're actually diagnosing a cancer that's in there. And so how do we improve this? I think there's a multi-modality approach. So you get better with the actual acquisition of the tissue. You improve the analysis of the tissue. And then you improve the optics for looking at this. So how do you improve tissue? Well you can try to do biopsy forceps. If you've supported ERCP before you know this is not an easy task to do to put a forceps in the bile duct and then in two dimension under fluoroscopy trying to target it to the right area can be difficult. When you use it in combination with brushing it improves the diagnostic sensitivity. And we had some studies looking at this where you combine brushing using a modality called FISH and biopsies. You can increase the sensitivity from like 17% with brushing, which is what the standard of care in the overall cohort to 68%. We're still not getting to where we should be, which is over 90%. And in patients with primary sclerosing cholangitis it's a little bit better, but that's because FISH is optimized for that in our center. Novel genomic markers are out there. And the reason I'm saying all of this is because you need to be aware of what's the competitive landscape. What are the threats to this? What are the opportunities? So it's not just what is the device, but also what can you do with the tissue that we acquire with this device? So I do think there's going to be improvements in NGS, in genomic signatures that will improve diagnostic testing. But as we see with cancers, even in pancreas cancers, our surgeons, our oncologists are asking us to get biopsies, to get histology, because then they can run it for more genomic sequencing that allows them to personalize the care that they offer that patient. It'll tailor the chemotherapy for that patient. So that leads me all to cholangioscopy. So cholangioscopy has been shown to improve diagnostic accuracy with ERCP. However it's a visual diagnosis. So it says, oh, yep, Dr. C put in this cholangioscope. He says it's cancer. It looks like cancer, but the biopsies came back suspicious. My oncologists, my surgeons love me, but they don't trust to treat a patient with cancer just based on the way I see it and say, yep, that's cancer. They want tissue. And they want tissue not just for saying it's cancer, but to actually personalize this care. So it's very limited in the ability to assess it just based on optics alone. So when you say, can you combine this with biopsies, it does improve diagnostic sensitivity, but again, not in a subset of patients with a specific condition called primary sclerosing cholangitis. These are the patients who are at high risk for developing cancer because of their chronic inflammation and scarring of the bile ducts. But we're limited even with combination modalities to actually diagnose cancer in these patient populations. You can see it's only an accuracy of 60%. So then we've come up with better ideas of how to classify, OK? So to get my surgeon oncologist to buy in, to say, yep, you see cancer, I believe you, I trust you. There have been classification imaging systems, most recently the Mendoza protocol, where they said, okay, if we see large tumor vessels, if we see papillary fronds, if we see ulceration, can we come up with some sort of consensus imaging features that will then say this is a high rate of cancer. And so again, what you see is they can get the diagnostic sensitivity to 90%, but then you put this into the hands of another provider. They may say, well, I'm not quite sure. I have a different interpretation of what this may be. So there's low sensitivity when you consider inter-observer variation. So one of the things I think that can improve this space and disrupt this space is AI. I think AI is helpful, as we're seeing in many other different things. We are one of the multiple centers that are looking at this. And basically what we've shown is through AI, you can basically help now level the playing field. So you can say, it's not me that is calling this cancer. It's an AI algorithm that's somewhat objective that is telling you this is cancer. So you see here this is flashing red, that means malignant in one of our iterative things. So now all of a sudden, you can take cholangioscopy and put it in the hands of someone who may not be as comfortable. And you can say, if you can get your cholangioscope up to this area, can you call this cancer? And guess what? At some centers that are using this, my colleague who helped develop this technology with me, the multidisciplinary team wants to know what the AI said. And if the AI called it cancer, they're shifting their clinical decision making based on that. So what we see here is the accuracy is higher than standard brush cytology forceps biopsies. And this is kind of our latest iteration of the AI. We have some data that we're presenting at DDW in prospective fashion. This is basically a patient where it looks red and irritated. This was actually called COVID cholangiopathy. The AI got it right. I would have gotten it wrong personally. There's another patient now all of a sudden you're seeing a concerning area and the AI is calling this. You can see it flashing red. I don't want to get into the nuances of this, but it's basically calling it malignant. This is a patient who actually had cancer. And then you can see it's cholangiocarcinoma. And you can say, well, you showed me two very different videos. Here's a video where it looks terrible. It looks red. It looks concerning. I would have been concerned about this if I just looked at the imaging here. You see it going back and forth. That's respiratory variation. It's the patient breathing and the scope going back and forth. So we'll talk about the need for stable platforms. This is autoimmune cholangiopathy. It's not cancer. I would have thought it was cancer and the AI did not call it cancer. The next I think big advancement is wire placement. This is a case I had two weeks ago where I couldn't get into the right duct. And I can see why now when I put a cholangioscope in that there was a narrowing here. So I didn't think a wire would just under X-ray would get into that area. So you use the cholangioscope to then target into this area. One of the things I struggle with is that the wire comes out at a certain orientation. And then to move it to get to that area is very difficult. My fellow tried and tried and couldn't get it. And so I had to do it. I've just done this a lot where I know where the wire is going to be. So it makes it look easier than it is because of some editing. But it's actually really difficult to kind of steer that wire where you want it to be, especially if the opening or where you want to direct your therapy is up in this area. And that hemisphere is very difficult because the wire always comes out in this orientation. So being able to steer devices or steer things requires a lot of manual torque and manipulation with the dials to get to that area. So that can be somewhat challenging. Now lastly is to direct and assess therapy. And I didn't want to talk about this too, too much because I think this is more futuristic. But as we're getting more into the therapeutic space, we're being asked to perform biliary ablation, RFA. I think Dr. Lee mentioned this. You know we're asked to decide, can you tell us what is the length of the tube? Not just is there cancer there, but does it involve the distal duct, the proximal duct? And can you do any sort of ablative therapies? So I think cholangioscopy is helpful for us to say exactly where does the cancer start, where does it end? And then if you're asked to do endoscopic-derived therapies, then you can go back in and take a look. Oh, did I actually ablate the area? I thought I was going to ablate. More to come. I think cholangioscopy is going to be an opportunity for cholangioscopy-directed therapy. What are the limitations? With current platforms, it's very difficult to keep a cholangioscope stable in that distal common bile duct. So you really need to park at least a few centimeters of that scope into the bile duct to have a more stable platform. So really something that's near the ampulla or near the entrance to the intestine, it's very difficult to assess with cholangioscopy because you just keep falling out. It's not very stable. Visualization can be challenging. Again, you need to put a lot of irrigation, you need a suction, you need to have large ports to be able to do this. And then it's also, as I mentioned, difficult to target either forceps biopsies or wire-guided placement. And it's a lot of kind of manual rotation using the ERCP scope, not the cholangioscope to get that angle. I should note that adverse events is something that is brought up with cholangioscopy. And I pulled up some of this data. We had written a guideline on this and we basically had said at the 2017 ASG guideline that cholangioscopy is associated with an increased risk of bacteremia and IE cholangitis is what we're concerned about. That's increased with biopsy sampling. But then when you look at overall patient events and you look at large world data that was published recently in 2024, you see that it's not really significantly increased compared to standard ERCP. Now I do give a dose of antibiotics for cholangitis prophylaxis any time I am going to perform cholangioscopy. We're going to switch to pancreatic disorders and we're going to talk about pancreatic duct stones and main duct IPMN, which is a growth that we see in the pancreatic duct. This is something that is kind of an expanding field for pancreatoscopy. So pancreatic duct stones are slightly different than bile duct stones. Pancreatic duct stones are calcifications that are hard. I mean these are really, really hard stones, unlike the bile duct stones that I showed you that can fracture and then when you're trying to pull them out they can sometimes fall apart. They can be soft stones. The stones in the pancreatic duct are really, really hard. And so what we typically do in these when we're actually asked to perform ERCP, we're trying to extract the stone. It's hard. So having lots of branches in the pancreatic duct is sometimes very challenging to pull these stones out. So we've shifted to two other modalities. So extracorporeal shockwave lithotripsy is basically where we historically would send these patients to a urologist. So imagine the urologist has to blast kidney stones. Those are hard as well. They said, okay, well can you just now shift your focus to the pancreatic duct and do that? What we've seen is that urologists are very hesitant to perform shockwave lithotripsy to the pancreas because the pancreas is not as forgiving organ. And so they're deadly scared of causing pancreatitis or bleeding. What we've seen is if you have a provider who is a GI provider performing this, the outcomes are much better. They deliver higher number of shocks for a longer period of time and it fragments the stones. There's been some data published out of WashU and some of the other centers that have shown you can just do ESWL for some of these patients and don't even need to do an ERCP to clear the stones. A lot of us are uncomfortable just fragmenting stones and not going in to clear them out. But what they'll do is they'll do ESWL and then at some time point later, then do ERCP to pull out the fractured stones. Either it's the same day or a couple days later or a couple weeks later. So what can we do endoscopically? We can again do lithotripsy for these stones. And this is a video from Sam, who's my partner at Mayo, where he's been using laser. He brought laser into our practice. And as you can see, this is a green homeom laser. And he's using that to fracture this really rock hard pancreatic duct stone. We've been using kind of laser lithotripsy for some of these really, really tough stones. You can see it tells you where it's going to fragment and then he hits it and steps on the pedal and delivers the laser lithotripsy. Now main duct IPMN, I mean I've got like half a dozen of these. And of course when I'm trying to put together this talk on a short notice, I can't find the best one that I have, but I found a fairly good one. So this is a high risk change in the main pancreatic duct. So patients with main duct IPMN are one of the few patients that we can see and we say your risk of cancer is extremely high. You need to get a surgery to reduce or eliminate that risk of developing pancreatic cancer. This is one of the few times that we can actually intercept a patient in their journey before going from a normal pancreas to a pancreas cancer, identifying it and dealing with it. And so what our surgeons have asked on occasion, not routinely, but at some other centers I think routinely, is can you map out that main duct IPMN? I want to know exactly how much is involved. And so what you see here is you see these papillary fronds. Basically these are the fronds that represent the main duct IPMN. The risk of developing a cancer in main duct IPMN is about 40%. That's why we tell people it's a high, high risk of pancreas cancer. Pancreas cancer is very lethal. So this is where the surgeon had asked me, can you tell me how far this extends so I know where to make my cut for surgery? Otherwise I may be forced to take the whole pancreas out. And in this patient we were able to identify where the papillary fronds began and ended. And so we spared that patient from getting a total pancreatectomy to only getting a partial pancreatectomy. So there's real world implications in main duct IPMN. Now again, this is not super, super common. But in that patient, it's extremely important to have this mapped out. Now adverse events with pancreatoscopy. Anytime we put a wire or a catheter into the pancreas, we're extremely afraid of causing pancreatitis. And I think that's going to segue well, nicely into Dr. Arain's talk. A snapshot of this is basically when you do dedicated pancreatoscopy where you're intending to go into the pancreatic duct, there was a recent review that showed no increased rates of adverse events with pancreatoscopies compared with standard ERP. Basically standard, not ERCP, but endoscopic retrograde pancreatography. They didn't need to go into the bile duct, specifically going to the pancreas duct. And there was no increased rates with pancreatoscopy alone. So conclusions, take-home points, cholangioscopy and pancreatoscopy represent exciting areas in both diagnostic and therapeutic ERCP. I do believe that these procedures have promise for more efficient therapeutic ERCP. They have to be easy to set up. The staff have to be comfortable using them. I think that the other thing I didn't put into this is cost is an issue obviously. But you can justify, if I'm going to use this device and it saves a patient from getting another ERCP, that justifies the cost of the device right then and there. And so I think that that's a conversation that people need to have and people need to understand. As you all know, having that argument sounds logical, but sometimes it isn't. Because the endoscopy cost center is looking at the equipment cost. They're not looking at the global hospital costs. So they don't care if the patient, they do care, but from a cost perspective, they don't mind if a patient's coming back for a second ERCP. But from a hospital insurance coverage perspective, of course they want you to get everything done in one procedure. And if it costs an extra X amount of dollars, yes. But to justify that to colleagues, especially some of my colleagues, to say look, can you use cholangioscopy? Well that's going to charge that patient X amount of dollars. I don't want to use that unless I have to. So these are things and conversations that I think anyone getting into this game are going to have to be skilled and know about the global landscape of how the cost benefit can impact that, not just the outcomes. I do think this can improve the diagnosis and risk stratification of biliary malignancy, something that is much needed. I think cholangioscopy is just one tool, but it's a really good tool for helping us in that direction. And again, as these platforms improve, especially with ergonomics, it was alluded to, the interventionalists suffer from a lot of musculoskeletal injuries, so anything that's more ergonomic, easier to use, is going to be helpful for adoption for endoscopists. And with that, I think we're taking questions in a Q&A later on, but this is again a team sport. This is me with my colleague, my former colleague now, Aliana, and our nurses. We work side-by-side, hand-in-hand, and the whole team needs to be comfortable with these procedures in order to have a successful procedure. And I look forward to your questions at the roundtable discussion.

cholangioscopy

pancreatoscopy

endoscopic retrograde cholangiopancreatography

artificial intelligence

biliary stones

pancreatic duct