I would like to thank the course organizer for having me today, it's my pleasure. And we're going to talk about when and how we close the defect. Okay, this is my disclosure. So the objectives of this talk will be we discuss about base, resection-based inspection after polyp resection, and we revealed a valuable technique for closure of the mucosal defect and the perforation, particularly about CLIP and suture, and reveal data on closure. So first, after we finish resection, EMR or ESD, it's very important to carefully examine the base of the lesion, because that can prevent delay complications, like recurrence or delay perforation. So what are we looking at? First, looking at the mucosal level. Mucosal level is the polyp, any residual polyp. You want to look at both the margins, around the margins, and within the defect itself, because sometimes there might be an island in between the snares that are left and we need to remove. And if you see any residual polyp, then remove it immediately, otherwise that will come back to be a recurrent lesion. And at the submucosal level, we look at the submucosal fibrous tissue. We usually see submucosal layer, and you may also see blood vessels. And identify these blood vessels and see if we need treatment. I will talk about treatment of visible blood vessels. And then at the muscle level is to look at evidence of muscle injury. This is a piecemeal EMR of a seagull polyp. We did it under conventional method, but sometimes we have water, so we just switch to water. So what I like to inject, so you can see blue at the submucosa, so you see submucosal tissue and blue dye. Like what Jason demonstrated yesterday, looking at the area underwater actually gives you about 1.3 times magnification. And you can see a lot better submucosal tissue and the margin. And we can see polyp right here. And this is a mucosal injection, not a submucosal injection. So it's OK. We're going to remove that residual polyp at the margin, along with this blep. It was coming out called resection. That's fine. This is just small hematoma. And then look at this side. We did not see any polyp. This is a residual. It's actually the fibrous cord, because that part was removed by coal. And use the snare tip soft coagulation to ablate normal appearing margins, about 1 millimeter in length. So we have to complete treatment. It's better than partial treatment in preventing risk of local recurrence. So that's just an example. And you don't have to do underwater, but it's also my preference. Next is look at the blood vessels. This is post-ESD. So identify blood vessel. That one was also pulsatile. You see it's pulsating. Use coagulation forceps, slightly pull forceps back to concentrate the energy, and then apply coagulation. Usually we use soft coagulation, not force coagulation for coagulating blood vessels. What is the data on doing this? It's coming from the study many years ago, post-ESD coagulation of visible blood vessels after gastric ESD. This is the retrospective analysis of over thousands gastric ESD. They found that preventive coagulation of blood vessels associated with decreased risk of delayed bleeding after ESD. So it's standard treatment, like when we completely resect the lesion, use coagulation forceps to ablate any visible blood vessels. But in the colon, we don't really have data to support. In this randomized study, they compare the EMR plus coagulation of blood vessels after complete resection versus no coagulation in over 300 patients after a large colon polyps EMR. And the primary outcome is clinically significant post-EMR bleeding. The group with the EMR group, risk of bleeding is 8% versus 5%, and there was no significant difference. So it seemed like in large colon polyps EMR, there's no data to do coagulation of blood vessels. And I myself also don't do coagulation of visible blood vessels after large polyps EMR. Usually we coagulate visible and pulsatile blood vessels. And generally, we see that post-ESD, not much EMR. And when we examine the mucosal level, look for any residual or blood vessels, there's an area sometimes that's not staining blue. And for those who are not experienced with using the underwater technique, they may have difficulty evaluating whether this area is submucosal tissue or this is muscle. In this situation, you can apply topical chromoendoscopy, basically the blue dye, like the injection that we use through the catheter at that area. And if it's stained blue, so it's not muscle. Muscle is white. So this will help us identify area of muscle injury. So this is intact. And this is a fat and submucosa and not staining well. After you stain blue, you can see that it's not muscle. So this is OK. And now at the muscle level, we look at evidence of muscle injury. And the SIDNEY classification has been described following colon EMR by Australian group. This data derived from the outcomes of over 900 patients that received large colon EMR. So they describe type 0 mean no muscle injury and up to type 5. So no normal defect. You can see that the resection plane is within the submucosa. We can see submucosa fibers, I mean tissue, and no exposed muscle. Sometimes you see blood vessels. And you see blue all around. So that's quite reassuring. Type 1 means that's an area that all submucosa been removed, like this area. And you see muscle. This is white area, circular or straighted muscle layer. That is exposed but not injured. So this is type 1 demural injury. So this is OK too. Type 2 is when it's unclear. It's unclear whether there is any injury, because the distinction between submucosa and muscle is not quite well seen. Usually it's from having serious submucosal fibrosis, or sometimes because of the fat. If we're not really sure, it's recommended to close that area. For example, this area, they are not quite sure. They close it. The other same, this is like a lot of scar tissue. And if we're not really sure this is scar tissue or muscle, part of the muscle coming out, it's recommended to place a clip prophylactically. Type 3 is when there's a partial resection of the muscle. And this is the evidence by target site, which is the circular ring, either at the base of the EMR or at the specimen. So this is EMR base. You see white ring here. Part of the muscle come off with the snare, this one as well. So it's important to recognize this and close it to prevent delayed perforation. If you want to continue to remove the polyp before you close it, otherwise it will be difficult to remove that area. And then you look at a specimen, you see the muscle, which is also the target site. This is type 3. Type 4 is mean full thickness or complete perforation. So through and through the polythene. But there's no fecal contamination into the peritoneum. This one, once recognized, also close immediately. Because air can leak, the defect going to get larger. And again, if possible, remove polyps around it before we close. And type 5 is that full perforation plus fecal contamination into the peritoneum. If you can, try to close it. But should also consult surgery to be standby. In case patient develop polytonitis. Also, the prevalence of demoral injury, type 3 target size to type 5 perforation is about 3%. 3% of overall type 1 to type 5. So it's not that common. And what is the risk factor? First is transverse colon location. It could be that transverse colon is intraperitoneal and mobile. So if we suction, we can get muscle into the snare. So that could be the explanation. On block resection of the lesion larger than 25 millimeter in size. So it might be advisable to avoid doing on block resection for non-pedangulated polyp larger than this size. In the lesion with high grade dysplasia or submucosal adhesive cancer, these lesions tend to have dysmoplastic reaction and will not live very well in that area. So it could be why there's a higher chance of muscle injury. So it's also important, this risk factor, and avoid or pay attention on the base of the resection site after EMR. So if there's a hole, then most common method of closure is still using hemostatic clip. This is easiest we are familiar with how to use and generally very effective. From the study, show the overall clip success rate means this patient can avoid surgery in about 70% to 80%. So majority of the time, this patient can avoid surgery. There are several brands of clips available in the market, different shapes, size. And the largest available now is 22 millimeter in size. And most clips now you can rotate and can close and open. The ideal closure for perforation, we should try to achieve deep closure. So to compare the two, deep closure, you get a lot of tissue within the clip from both sides of the defect. And there's no space left within the clip, whereas look at this clip, almost fall off. So this clip will fall off at the end of the procedure. So we should try to achieve deep closure to achieve protective effect of the clip. And before clipping, find the position. Try to align the defect at the center or toward the left, slightly left of the screen. It will be easier to, because when we advance clip, it go toward the left side. And we use suction of CO2 to approximate edges of the defect. And one thing that very important to recognize is that clip retract when we close. That's the mechanism how we deploy clip. So if we, when we know this, then when we ask assistant close the clip, we need to slightly push the clip forward. Otherwise, we end up with superficial closure. And consider using sipping fashion closure, which is less than 1 to 2 millimeter space in between clips. This will, you can achieve the proof, conceal the leak. So if, but if you close for prevent of bleeding, may not need every 1 to 2 millimeter. But for perforation, try to close next to each other. So this is a poly, 20 millimeter on block resection in a transverse colon. And after we close it, I mean after we resect it, we see a hole. And I think everyone can see, like, the muscle layer here is very thin. So now we're going to clip it. There's no contamination, so we immediately close. So first clip went the center. We don't like it. Like, better the first clip go start outside so that the diameter becomes smaller. Slightly gently push and close to compensate for clip retraction. And now the following clip, the diameter of the width of the defect becomes smaller. Next clip go next to that one. And because it's a perforation closure, we do sipping technique. And after, slight gentle suction as well to move both edges together. Check the position of the clip, both side. You can see there's no gap at all. Check this side, and go and check the other side. And if there's any rest part that we don't see, we see exposed, then you can add clip. Besides clips, what else we can use for iatrogenic colonic perforation? You can use over-the-scope clip, an endoscopic suturing device. But we have much less data on efficacy, so the available study success rate is very high, 90% to 100% in closure. The limitation is that you have to remove the scope and reinsert the scope to the location of the perforation. So if it's in the right colon, it's very difficult to do. And during that time, there might be contamination, or the defect become larger, or you may not be able to get back there. So this generally still limit to the defect in the rectum or in the distal colon. Let's move on to prophylactic mucosal defect closure, not for perforation. After the mucosal resection. So we have multiple randomized studies show that closure of non-pedunculated, after EMR of non-pedunculated polyps in the right colon decrease risk of bleeding, quote unquote, with coagulation, not for co-resection. So this, I think our speaker already mentioned this meta-analysis. I just showed a graph. This is a meta-analysis of individual patient study from four randomized trial. So over than 1,000 patients. And you can see the risk of bleeding in non-clipping is 9%, versus 3.5% in clipping group. And number needed to treat, number needed to clip to prevent one delay bleeding is 18. So it's actually not too bad. And if you look into the detail, interestingly, the delay bleeding in transverse colon is actually very low, only 1% after last poly-EMR. Most bleeding is in the cecum, followed by in the ascending colon. So now what I learn is in the cecum, I will close, I try very hard to close complete closure. So here, if you look at partial and full complete closure, it's still better to attempt closure, even though it's only partial, because the risk of bleeding is still lower, like 1% versus 9%. Better than not attempting at all. So if you can achieve full closure, that's best. But if not, try to close it. So does it improve, decrease other risk of complication? It decreased risk of delay bleeding, but doesn't decrease risk of delay perforation, post-polypectomy syndrome, or abdominal pain. So no other protective effect of clip. Another meta-analysis, this one, including both randomized and non-randomized study, look at delay bleeding risk. So if we know that for proximal polyp, large polyp, risk of bleeding is lower, significant p-value, but we see that especially if we can achieve complete closure, and a patient with that on anti-thrombotic. So these are, so we try to achieve complete closure if we can, and particularly those who are on anti-thrombotic. But clip closure does not decrease delay bleeding for large distal polyps and smaller polyp, polyps smaller than 20 millimeter, even those who's on anti-thrombotic. So that's what evidence say. How about for colorectal ESD? There are not that many studies in closure of colorectal ISD defect, of eight study, only three randomized studies, but they are small randomized studies, over than 1,000 patients. Similarly, it showed that prophylactic clip closure decreased risk of delayed bleeding. Delayed perforations, P value is like 0.5, so it's not significant, but borderline. And does not decrease risk of post-polypectomy syndrome. So, but the problem is we don't know what type of lesion in the colorectal ISD that most benefit from clipping. It might not be practical to close all the defect. But risk factor of delayed bleeding after colorectal ISD is lesion larger than four centimeter, rectal lesion, patient on anti-thrombotic, so during procedure, you encounter more than three arterial bleeding. So this may be the lesions that you consider close, but we don't have the study to confirm that. What is the main challenge of a clip closure? If we can, we want complete closure, but complete closure, like in the study from a large poly-EMR, you can achieve complete closure in only 60%, 60, 65%. So, most of this, you can't, so what do we do? There are many modified clip closure techniques that can improve a rate of complete closure, like hole and drag, I think Sri has shown that, string suture, clip, there are so many, but we'll show some of them. Or you can just use alternative devices, like suturing or the scope clips, or through the scope suturing. So I'll talk about some modified technique. In this way, we don't need anything more than just clip. So the first one is hole and drag closure technique. So use a clip and close clip at the one side of the defect. So usually when we close clip, we align the center of the clip in the middle of the defect, right? We're not doing that here. We close it at one side, and then drag or advance scope to the other side of the defect, open the clip, and grab, now grab the other side, and then close. Now the defect becomes smaller, so you can follow by smaller clip to close it. So there's a, after we ablate that lesion in the sacrum, okay, looks fine. So this is the regular clip, not the mantis, but you can see, like, grab one side, and okay. Now this is the other side. Okay, move a little bit. Open, don't come out. So adjust, and then grab the other side. Slowly advance and close. First of all, this is superficial closure, but at least it make the defects become smaller. So usually we don't rely on that clip to hold a defect. It's gonna come out, but we're gonna add additional clip, and this one is better closure, and we're gonna add additional clips next to the first one to reinforce that area. So this is the first one you see superficial closure, so add another clip there. So the key, the other thing is don't keep pushing the clip. Go in with the tibiotoscope, and adjust the clip and have it on force. So now you can see, now we achieve complete closure. Okay. So what is the data on this technique? Published by Japanese group since 2016, they closed post-ESD defect in 19 patients. The mean size of the defect is four centimeters, very big. So our complete closure is 94%. So this is very good success rate, and no adverse events. You can see the clip they use is different from what we use. When they do drag technique, they use the bigger clip, but when they reinforce, they use smaller clip, and the smaller clip have smaller stems. It's not coming into view when you try to close the remaining defect. Otherwise, all the clip sticking out from the defect, and you can't see the defect very well. So that is helpful. The newer clip by Boston Scientific called Mantis Clip has the anchor plonk. So this, the tip here, embed into the tissue. So when we do this hole and drag technique, when we open clip to grab the other side, many times it slip off. But with this anchor plonks, it prevent the tissue from slipping away. So it might improve success rate of doing this technique. Another clip, this is from Microtex called Dual Action Clip. So basically have two independent clip component, the yellow and blue. So you can open one side at a time, or you can close both side at the same time, or open one side and close one side. And both each sides controlled by different handles. So this is an example. After resection, this defect is wide. So to approximate, it's not that easy. Open one side, grab and drag, and then open another side. So first, do this in the center of the defect to make it small. Now, you can see the diameter is, the remaining defect, you can use regular clip now. And just one or two more clip, and we can close the entire defect. This is also available. So another technique that simple to do is called string or suture clip method. So tie suture to one side of the clip. So, but it's better to use it with 3.2 millimeter single channel, not 2.8. Otherwise, it's like keep pulling the clip. So with that initial clip, hold, I mean, clip the far side of the defect. And then next clip, the near side. Then pull suture from outside the scope. Now you see both side of the defect come together. Next clip, you press to reinforce. And now the defect become narrow. Now we can close it with the smaller clip. Cut the suture. This is scissors, endo-scissor cutter. This is a second string. Far side, pull, and the near side, and then reinforce clip. And now this is a large duodenal EMR. And the endoscopist was able to close it completely. In the, this method was described actually back in 2016, published in 2018 in 10 patients. Close duodenal EMR, ESD. Like this is almost four centimeter defect, very large lesion. Success rate is 100% in Japanese pen. Okay, it may not be 100% by us yet. Time to do this procedure is 20 minutes. So it takes some time. And they found that the patient has shorter hospital stay when you close it. It might be that it decrease delay bleeding during after procedure. So there are many more modified clips technique, but those are the one that commonly used. So let's move on to the different devices. Let's first talk about suturing device. There are, or overstitch. There are now two versions. One is overstitch, a low-end overstitch SX. So the difference is the SX is using with the single channel scopes. Whereas the original overstitch, you have to use it with double channel scope. And only this double channel scope, this Olympus 160 and 180 on Fuji film, this version, not Pentax double channel scope. Whereas this single channel scope is overstitch SX, compatible with more than 20 scopes from four platforms. So if you decide to buy one, you have to think about what scope you have. And Olympus no longer manufactured this double channel scope, only Fuji film. So another difference is, because this overstitch SX, everything go outside. So you have one additional channel because the helix can also go outside the scope. Whereas there's no additional channel for the regular overstitch. And because there are these two options, the helix can go to this one or this scope, accessory channel. You can adjust it. And this mounting tower, you can adjust the orientation. Whereas the overstitch, original one is fixed position. So let's see, this is the original overstitch. So after remove the lesion, okay, we have everything ready. First, have to bite at the mucosa to the defect, not defect outside because the first bite will be where the synth will be deployed. It has to be at the mucosa. Now exchange. So you can go from left to right or right to left, but maybe easier to go from right to left because you can see suture on this platform. You can see suture on the right side. Now, before go to the next bite, we have to have slack. We're not sure all this. And then let's move on. This is a third bite. So the more tissue you get, the better, more secure. If you get too superficial tissue, it will like just rip and tear the mucosa. And this is just continue. What is the space? Probably about one centimeter space between the bite should be enough until the last bite. Okay, so now that's... Where's my synth? Okay, we already dropped the needle. And that's the synth. You can see it go to the first bite. And this time we need to pull suture tight. So all the suture will slowly go through the tissue and come off through the scope. And then once it's tight enough, then deploy. This is a 2.0 suture. That's the overstitch original one. This is overstitch SX. This procedure done by Muhammad. Thank you for the video. So the full thickness resection. This is PENTAX single channel scope. And you can see the orientation of the suture is different. It's at four o'clock versus the other one it was at seven o'clock. And the needle tower is coming from lower up. You can see that was, I missed that. That's a helix. So this helix going through the channel outside the scope. Pull and take the bite. So let's see the initial bite without helix. It was very superficial here. Yeah, so very superficial. So he say he didn't like it. He try again with helix. Now we get deeper tissue and more secure. And do the same technique. And now this is helix too, but come through the scope at five o'clock from the PENTAX endoscope. So because you have additional one more channel you can choose whatever channel you want to use helix. And the rest is the same. Other technique the same. Deploy the cinch. And this is closure, complete closure. What is the data on suturing to close vehicle cell defect? Not a lot of data. So far I found two study including 43 patients, both gastric and colorectal. But 21 of these patients have a digital colon, lesion in the digital colon or rectum. And the resected specimen size is almost four centimeter as well. Usually we need only one, but we can use most patients require one to three sutures. Take about 10 minutes to close this defect. No reported adverse events due to suturing. And most of these patients can be discharged the same day. It doesn't mean if you don't close you cannot discharge patient, but it's just more reassuring. Another device is called through the scope suturing device, which this has the helix tags at the tip. So this is through the scope. So we don't have to remove the scope to put the instrument on. Now we can use it through the scope anywhere we are in the GI tract. And it's designed to reach the muscle layer, but not through the muscle layer. So in one system, if you open the system, it has a four, five millimeter tag. And each tags connect with the suture. So this is already deployed. As mentioned, it should reach to the surface of the muscle layer. And when we deploy this thing, sorry, this tag, we want to deploy as deep as we can. And after we deploy all the four tag, put the things the same way with indoor suturing and tighten the suture. So you can see that it's close up the defect because each area has a tag located at. So let's look at the video. This is a three centimeter lesion in the ascending colon with depression or maybe recurrent too. So after remove it with ESD, the defect is like this. It's a little bit over the four, but when you deflate, suction air is small. The defect looks smaller. This is the system. This is a X tag. You can see go through, it can go through the scope. Either like 2.8 or 3.2 millimeter channel. Both, this is a first tag. A gentle push, what important is try to stay on force. That way it go deeper. And the assistant close the handle, it turn, drive the tag into the tissue. That's the third one. And then you lie it, do deploy. Usually we add additional more turn, like three more turns. You see it going through the tissue nicely. And once we finish that, put a cinch to hold the suture. The same way with the endosuturing. If we doing this closure for the large defect, we need either more X tag system or you can put clips. Depends on what remaining defect look like. You can calculate how much more cost it will be. For this one, we use the second tag. And with two tag, it close the defect completely. So what is the data on this? So this, the multi-center study, we looking at the prophylactic closure of X tag. This through the scope suturing after cortical ESD. And the median lesion size is larger than three centimeter. In 82 patients. So complete closure was achieved in 92%. So was just 65% of the literature for clip. So that's look pretty good. This 92%, it could be clip, sorry, X tag alone or through the scope, plus putting clips at the remaining defect. Okay, so let's, oh, I have time. So take-home points. A careful inspection of the resection defect is critical. Important, we have to identify and treat mainly residual adenoma and evidence of a neural injury because that's when you can prevent recurrent adenoma. Because that's when you can prevent recurrent adenoma and delay perforation. And of the classification of deep neural injury, the type three and type two, type five is what we strongly recommended to close once you identified. Type two is a type that is unclear distinction between submucosa and muscle. Ideally should be clip as well if you are not sure. And prophylactic closure has been shown to prevent delayed bleeding for both EMR and ESD. So for EMR, if we remove the large polyp larger than 20 millimeter in the right colon, we should close the defect if we do EMR. For ESD, it seem to decrease risk of delayed bleeding, but we still need to did more data to know which patient we most benefit from clip closure. And if we cannot achieve complete closure, there are many other techniques that we discuss that you can apply or use alternative devices to achieve complete closure. Thank you.

careful examination

closure of the defect

polyp resection

complications

recurrence

perforation

techniques for closing the defect

prophylactic closure