I guess the first question I saw from the chat was actually a great one, blending both worlds. So, can you do cold-snare polypectomy underwater? There was a paper on cold-snare polypectomy underwater. I've never tried it, and I'm not sure if it would give any advantage except, you know, all the benefits that Ashley just sort of mentioned. I think some of those videos were really amazing, and I think, you know, with cold-snare, you're really essentially doing mucosal stripping. You're not really, you know, cutting into the submucosa, and I think, you know, the more concerning vessels are in the kind of SM2 and SM3 layer, and I don't think you get there with cold-snare. So, I think there's a lot of appeal with cold. I also think, you know, the submucosal injection is important to loosen the submucosa. So, if you're underwater, if you're talking like not doing that underwater, the times I kind of do this sort of pseudo-underwater is if it's an area that I'm having a hard time grabbing. So, the underwater allows you to minimally distend the lumen and sort of hope that you can get it in the snare. So, I do that sort of modified. I mean, I was actually curious, you know, what you guys do. You said that was a terrible prep. That was like called a good prep in Cleveland. I mean, that looked pretty damn good to me. So, you know, you're at the seacum, and the small bowel just keeps pouring stuff out. I mean, I think that feels like the biggest limitation for underwater is like, I mean, that was a pretty good prep. I don't know. Yellow color is not a problem. More like solid debris coming in. We got a question from the audience. I'm talking about the prep for the underwater. Do you do a two-day prep standard or just a normal prep and hope for the best? Yeah, normal prep and hope for the best. You know, I think the seacum is the hardest part because of what Ashley said with, you know, all the stuff coming through the ileocecal valve. But actually, you know, because underwater doesn't take that long, as long as that local area you can get clean, you know, it's not too bad. The other thing is with underwater, you can do this sort of filtering thing where, you know, you're suctioning, and then you're instilling, and then everything sort of gets, you know, And after bleeding, that's sort of what you do. You're kind of putting in with your foot-activated water jet, and then you're suctioning, and everything is just clearing up over time. Is cold water better? Is cold water better? Or is the temperature of water affect peristalsis or help with water retention? Yeah, that's a great question. So, you know, there have been studies looking at water exchange and water immersion colonoscopy with warm water, where there was a randomized study that looked at that, and it was felt that there was maybe a warm water did reduce peristalsis. What I would say, though, with underwater EMR, peristalsis is actually a good thing. And so, and there's a study that was published in Japan, and Dr. Ben-Muller's on that one as well, looking at, you know, specifically peristalsis and how it helps sort of move the polyps sort of into your scenario even better. So I actually like peristalsis. We've got a question back. And when you're asking questions, if you can hold down the button on your microphone so the folks online can hear what you're saying. So for underwater polypectomy, two questions. Number one, we are not using indigo carmine or methylene blue or orice gel. So how do you know that you've injured the musculus properly or not? There's no target site. Number two, if there's a perforation, if you already immersed that segment of the colon in the water, liquid will immediately leak out due to peritonitis. So what, any comments about this? Yeah, I'll start with your second point. So I think that was one of the biggest concerns with underwater EMR, is if there was a perforation, you'd essentially be having, you know, lots of liquid going into the peritoneum. And unfortunately, you know, the rate of perforation seems to be very low. I actually had a perforation one time in the years I've done this. And it was in the acinic colon. And there was a, it was at a tattoo point. And that's sort of why I kind of caution with underwater EMR and tattoo. But it was interesting how well the patient did. And it was almost like the, when we did the CT, there was a little bit of fluid around the acinic colon. But I wonder if the water actually served as a bit of a water seal when it sort of left. Because she did surprisingly well, had really no pain. And we presented at ACG as a sort of a poster presentation. But we were able to, so in that scenario, we, you know, clearly water went into the peritoneum, but it was clean water. And we closed up the defect with clips, you know, got, put it on the fluorotable, got x-rays, you know, there was no leak. And, but it was surprising to me how well she did with really no peritoneal signs, you know, a very mild white count. And so one of the things that we were wondering about was, you know, because we were taking our time to close that perforation really, really well with clips, I would have expected more free air on the CT. And it was just minimal. So I just want to comment on the perforation. I'm sorry I had to step out. I had a Zoom meeting with people from India. And I had to go India and England. So I'm very sorry that I stepped out. But I would like to say that minimal contamination in the peritoneum is not a big deal. Even if a small amount still go out, you can just go with the scope, flush the area and clean it and suction and go back in. If you have a good closure and you give a patient IV fluid and antibiotic, usually within 24 hours they do well. And a lot of times they don't even have pain. You'll be surprised that they are asymptomatic. And we learned that when we're doing full thickness resection of chest and other tumor that going into the peritoneum through the GI tract is not inducing a lot of inflammation as cutting the skin, for example, when you are doing access like by laparoscopy. So in a way, if you have a good closure, if you have a continuous leak, that would be the problem. So even if you have some water go out, I don't think it will affect the patient as much. I have just a comment on a great presentation, Jason, on that rectal polyp that you removed with mixed LSTG. So those are probably the lesions that start carrying a higher risk for cancer. If you look at the data of lateral spread and granular tumors, particularly in the rectum that that large and mixed have a higher risk of covert cancer. So ideally, like some of the European guidelines recommend removing those in one piece. So the only way of removing that in one piece is with ESD. Now, as Jason demonstrated, you can do piecemeal EMR. And I don't know if you guys paid attention, but he removed that big polyploid area of the lesion in one piece. So, you know, it's very important. If you're going to piecemeal these type of lesions, you want to identify the area that may be a higher risk of submucosal cancer, remove it in one piece, and consider even submitting it separately from the remaining piecemeal portions and mark it for your pathologist. So you can resect the piecemeal if MBLOC is not an option, but just remember that. We'll do one more here, and then we'll cut to some of the ones from the audience. Underwater, you know, arm, is there any, like, commensal or patient position? Not really. I don't think that factors into it as much, except when there's bleeding. So typically, when I'm doing a conventional EMR, I always put water around where the polyp is and see where gravity is. And if the gravity and the puddle is directly on the polyp site, then I will usually move the patient, because the assumption is whenever I take out a snare I'm going to use hot, it's going to bleed, and that bleed is going to just pool, you know, exactly over the vessel that's bleeding, and that's a much more difficult scenario to deal with. And so before, you know, doing the EMR, find out where gravity is and move that patient so the puddle and the bleeding will go into a different plane. Yeah, that's a good point. Another option is to just, I usually like to move the patient and get the polyp where I want it, so sometimes I, like, have them go on their back. I don't use propofol for these patients so that they can hold their breath, move. And then if they have bleeding, you know, you were showing that video and I was thinking that at the time, you want to move the patient away so the blood puddles elsewhere so you can see what's going on. So it's a great, simple technique if you have the wherewithal. If they're really bleeding, you have to kind of take a deep breath and be like, okay, what's going to help me? But moving the patient so that it pours away and doesn't puddle there is a great suggestion. We have a question from Mexico. If they screamed, they'd probably be louder than me. Cold snare plus ablative techniques. Audience comment if you do cold snare. Would you add in snare tips off coag on the margins or no? You could. I think I use it more on the base areas that I have trouble with. Because I just think the margins, I don't know, in my mind, I know the jury is still out for sure and there's, you know, people looking at this. I know Heiko is pretty interested in this and Doug Rex and others. But I, you know, I don't think there's a lot of harm in doing the hot snare to the edges. Like, I think that that's probably not going to cause you bleeding or perforation. And your snare, you're dragging your snare on the normal, right? Or whatever the edge is. Not in the base. But I just prefer to just cold snare all that because it's very easy to do. I think it's the base that you get into trouble. So I'll use like hot avulsion or other techniques with heat if I need to. Because I think the base is the issue. But I don't have any proof of that. I don't know. Mohamed, what do you think? I agree with you. And I feel like you should have a mindset. If you want to go for cold snare, then you want to avoid coagulation. Then you're worried about post-pulpectomy syndrome. Then I would avoid it altogether and just use cold snare. But yes, there's nothing will prevent you from doing like soft topical. Especially using the tip of the snare. The amount of cautery is very minimal. So it may not lead to post-coagulation syndrome. But I personally didn't do that. And I feel like, you know, people like my assistant would like that. I'm not doing hot snare. So they don't have to put the pad and we are finishing quickly. And now you're asking them to add other stuff. So it's silly. But sometimes you don't know what you're getting into, right? Like you think, okay, this is going to be great. I'm going to take it out with cold. And then you get to a part where you just can't. You're not going to be like, you know, you're not going to send the patient off. You're like, sorry, I committed to cold. I'm not going hot. So I think, you know, you do what you can do. I feel like, especially those fibrotic bands that I sometimes run into. And then I'm just like questioning my decision. But I feel like theoretically there should be less risk. Because if you're only using a small area where you're using thermal therapy. But then comes the question, do you clip clothes? And I don't know the answer to that either. It's complicated. Just a couple of comments. So I think when it comes to edges, the way I think about it is really depicted nicely in that video. I think it was Heiko's video. Where there was just clear intentionality about what he was doing with those edges. And I think if you have clear intentionality about the edges. And I think that example is beautiful. Because he clearly, and if we had seen the rest of it. Probably, you know, was 50-50, 50-50, 50-50, the whole way around. And then there's no question. There's no question about those edges. And I think with underwater, we're sort of very much the same way. Each piece, we're taking a lot of normal. A little bit of polyps. So then there's intentionality at the edges. As opposed to starting in the middle. Hoping that you're going to get it. So I think the edges absolutely have a lot of intentionality. When you're approaching that with whatever modality you use. In terms of the little bits of islands. You know, I've done APC. Snare tip cautery. Hot avulsion. I don't think, personally, any of those ablated methods work. And I've gone completely to resection. In any way possible. In kind of the manner that I just demonstrated. I just, I've been, you know. Burned, you know, sometimes. It's like, you know, I go back. Look at video. And there's a little bit of maybe, maybe something there. I think the underwater inspection really helps to sort of discern where those little islands might be hanging out. Because even if you leave a little tiny morsel of a polyp. You know, it's going to come back. But there is evidence that the recurrences can be removed. So it's not like it's, I mean. You're bringing the patient back, right? You're not going to take out a five centimeter polyp and be like, See you in five years. So you're going to bring them back. If they have a small recurrence, you typically can deal with it. But it's nice to come back and have nothing, you know. Especially for the patient. That's what I meant, of course. Not for me. Especially because it's sort of like, you know. When they come back and there's another one. Oh, I've got to go through this again in three to six months. That's a real pain point for them. So that's probably the biggest driver for me. You got a question way in the back? Yeah. Sorry. I'll have the mic back here again. So thanks for the lecture. One of the questions I'll raise is practical for those in the audience. Which is, maybe each one of you can comment. Whether it's underwater or cold snare or your choice of snare. Because I often find myself in these positions. And I just go with what I normally go with. And especially, you know. If we're talking about it larger than, you know. The data up to the 15 millimeter mark for cold snare looks great. There's no bleeding. But as you showed in that last video, Ashley. And that we, you know. The slide, the video ended very quickly at that. It started to ooze and bleed. That's a reality of it, right. And for a larger polyp, cold snare polypectomy. So you will switch to some sort of, maybe, bleeding control. Or snare tip control. But for a larger polyp, cold snare polypectomy. So you will switch to some sort of, maybe, bleeding control. Or snare tip control. So you have to use something with cautery. And most of our snares are. There are some that aren't. But if you guys could just from a practical standpoint. Maybe for underwater or for cold snare. For a larger polyp. What is your snare of choice? And is there any rationale for that? So for the underwater. I use a monofilament stiff snare. It's the. There's only two monofilaments. The snares on the market. This one is made by ConMed. It's called the Beamer snare. And I think that's kind of what I've been using for conventional EMR. And I think that's kind of what I've been using for conventional EMR. For the longest time. And when I started doing underwater. I just sort of stuck with it. But one of the things that's interesting about underwater EMR. Is you don't need a stiff snare. And the duckbill snare is not considered a real stiff snare. And the duckbill snare is not considered a real stiff snare. And so I think the. And I know Chris is using. And I know Chris is using. Kind of an oval snare. That's not particularly stiff also. So I think for underwater. So I think for underwater. I think it's quite variable in what you can use. And I stuck with the monofilament stiff. Just because that's what I've been using. Just because that's what I've been using. So I'm not an ESD person. And so I actually use. Mostly 15 millimeter or smaller snares. Mostly 15 millimeter or smaller snares. I started using Captivator. It's a sort of a stiff snare. But I'm not like selling anything. We all have contracts with different companies. We don't always have. I think you have to try them out and see what you like. I actually. I did the Rocky Mountain Interventional course. And I was sitting next to Mike Bork. He probably never wants to talk to me again. But I just asked him a bazillion questions the whole time. And he basically was like. I don't use anything bigger than a 15 millimeter snare. Due to risk of perforation. And we were discussing epinephrine. And contrast and whatever. So I came back and I was like. I'm getting rid of all of my big snares. And I'm using. So I use a 15 millimeter snare to piecemeal. I mean you can get a 20 millimeter polyp. And a 15 millimeter snare generally. So it's not like I'm piecemealing little polyps. But I generally don't use big snares. Because they make me nervous. But you did a great job. You know when you're like putting this big thing out. And capturing who knows what. And you maybe can't see beyond it. It makes me a little nervous. That was Chris. There you go. So I kind of like to see what I'm taking out. And the underwater thing. I mean it's great when it works. But you do have to have some comfort. In not seeing. We're all about seeing everything. So if I could just say one thing about Cold Snare. So there's. You know. The Lesion Hunter by Microtech. Is a unique snare. And I talked to the engineer. That designed it. It's got a little metal cap. That's slightly serrated at the tip. So it's closing the polyp on now metal. As opposed to the other snares on the market. So what I found with that. Is the cutting ability is just incredible. And so. I think that. You know. When devices like that. You know sort of. Kind of raise the bar a little bit. In terms of like how aggressively you can be. Because I think you know with a lot of snares. When we get in there. We're like we grab too much tissue. And we're kind of stuck right. So I think with that serrated metal cap. On the tip of the catheter. It really can cut you know quite a bit more. And now it's almost like. Well why am I even doing underwater. Or conventionally. I can just cut it cold. Without even lifting. So it's. I think as a technology changes. And new techniques come about. And even this snare. I was really kind of impressed recently. With you know what I was able to remove. And try out the ones here. Because I actually. We just got that one from Microtech. And I've only used it a couple times. So I think trying the different ones. Is great. Especially here. It's a little hard. Because we have devitalized pig stomachs. But apparently that snare can cut through this. And I just remembered. I've had patients over multiple sessions. And so I've had. About a 20 centimeter. Polyp. In D3. And this gentleman is very old. And on blood thinners. And you know surgery doesn't want to do anything. And so I've been working. On this polyp. And you know we'll work on it for like. You know an hour and a half. And we'll just cold snare. And then we'll bring him back. And we'll keep going. Because cold snare doesn't actually. Lead to a lot of submucosal fibrosis. So I think multi-session cold snare. Might be something new. But hopefully we'll finish this. And publish it. Yeah I was going to say. I don't know that we know that for sure. I sort of wondered that. Because you're not using thermal. But I mean there is scarring. Yeah I don't know if we know that. I mean the duodenum also might be different. Duodenum. I think it's you know. You're right. I do the same thing. All right take off a little bit more. And then they come back. And there's more there. Underwater. Any preference for sedation. Like MAG versus conscious sedation. Or from technicality standpoint. I think so. You know I think. These procedures tend to be a little bit shorter. Usually. It's interesting now. With scheduling. I'll kind of review the chart. Carefully. I'll look at pictures as much as I can. And then sort of plan. Almost like a 15 minute interval. Like how long it's going to take to remove this. And most of the cases are going to be underwater. And so. I think. I think in terms of sedation. I think either would be appropriate. Most of our cases are propofol. Okay. Question. Yeah. So I think. I think lesions with prior resections. Still kind of make me nervous. So I haven't been doing a lot of that. Most of those I'm still lifting. And then because of that. Complication with tattoo that I had. I'm not removing anything with. Extensive tattoo underneath. With underwater. Question. I have a couple of questions. First question is for. Cold snare. I've noticed sometimes there will be a little stuff. I'm not sure. What do you think? It's been studied. And it's not neoplastic. So that's the good news. Yeah. But that's. You see. You often see that in just flat little. Pops that you take out. Pedunculated. You know. Probably similarly. But for sure the flat ones. We always see that. And actually someone thought. To biopsy. I think it was Doug Rex. And found that it was not neoplastic. If you have an SM1. You would assume they don't have a problem. So do a CT scan. We go through the tumor board. Do a PET scan. And do it one year to two years. But we don't have any long term data beyond that. If you have an SM2 or SM3. They should ideally go for surgery. But. And I want to say that. You can give chemotherapy and ESD. Which is already done for esophageal cancer. And we have studies. In Japan. And we have my study. And the study from Cleveland Clinic. For the SM2 lesions. In the esophagus. Not in the colon. That you can give chemotherapy. Or even conservatively. And they do well at least for three or four years. But in the colon. I think it's a higher risk. Especially in the rectum area. So I would recommend surgery for this patient. But if they are not able to go for surgery. If the surgery is not that hard. Then they can go for chemotherapy. But most of the time. SM2 and SM3. They will go for surgery. You use those. When it's hard to distinguish. SM1 versus SM2. Do you send those patients for FTRD? So FTRD would be a great option. As long as the lesion. Is less than two centimeters. But yes. Any time. The best option we have right now. Is AFTDR for this lesion. You mean like getting rid of the scar? Because if you already know the SM. It's more when the pathologist can't commit. I mean you can ask your surgeon. To do transanal excision of the scar. If you want to see. I think there's more and more data. Although I don't know. I can't spew it out. About rectal cancer. And early rectal cancers. And observation. There's a lot of patients. That aren't great surgical candidates. And I think in Europe. They're observing those patients. And they're not going to surgery. So there's more data coming out about that. So we may be able to get away with more. But you could always have the surgeon excise the scar. I think we're kind of at an interesting point. Where we're just being asked to do. More of these staging ESDs. Than ever. So ESD is not ever. Curative intent. It's always for staging. And so. When I'm asked to do an ESD. We tell the patient. Well this is not going to potentially cure you. There's a lot of other things that need to. Kind of boxes that need to be checked. With the pathologist. For this to be deemed curative. And so a lot of the times I explain it. This is going to be just a mega biopsy. Where everybody is going to get a lot more information. About what's going on. And I think. I know Mohamed has felt this too. I think a lot of our referrals. Are coming from the surgeon now. And because they're asking. Well you know. Why don't you guys go after it. And then it's these huge rectal things. And it's going to take a long time. Definitely not as fast as him. And it's like yeah. I think it's the right thing for the patient. But I think now our esophageal surgeons. Are saying the same thing. You know I was referred. I have endocrine tumors in the stomach now. So I think. And again all of these things. Are not for curative intent. They're really to understand. What's going on. So I think. That's sort of important to keep in mind. And also talk about with the patient. I think there's a lot of questions. We do need a break. We'll just go to break. But we have lots more opportunities for questions. I think the day goes on. Thank you.

cold-snare polypectomy underwater

mucosal stripping

submucosal injection

pseudo-underwater modifications

water exchange colonoscopy

peristalsis