Good morning, and of course thank you to the ASGE and Professor Yahagi and Fukami for the opportunity to give this talk. Here are my relevant disclosures. So we're very fortunate nowadays in the U.S. to have multiple knives available for us to use. This was not always the case. Given the brevity of the talk, I'm going to concentrate on one knife, and with some trepidation because there are people in the room that know much more about this knife than I do. But I was recently on a panel of U.S. endoscopists talking about ESD equipment, and I was surprised to find that very few people in the U.S. actually use the IT knife. I think it's a very efficient and safe knife to use, but it takes a little time to understand how it works and what are the nuances. So the IT knife has an insulated ceramic ball at the end of it, and on the back side of the ceramic ball are the short blades of the knife. Attached to that, extending to the catheter, is the long blade. So you can cut with both the long and the short blades of the IT knife. They come in two major varieties, which is the IT 2 knife that has the longer short blades on the back of the ceramic ball, and the IT Nano knife that has a more streamlined ceramic chip, as well as a disc rather than blades, and it doesn't extend all the way to the end of the ceramic chip. IT 2 knife is generally used for gastric ESD, but as the short blades can touch the muscle layer during dissection, it's generally avoided for clonic or esophageal ESD, where the IT Nano knife is preferred and can access into narrower spaces. So these videos are a credit to my friend, Dr. Citro Abe. So here's an example of how to use the IT knife using the long blade for dissection during gastric ESD. So a mucosal incision has already been made with a needle-type knife. The ceramic chip is used to hook into the submucosa, and the knife is pulled, cutting with the long blade of the knife. As you can see, it allows for nice, controlled, fast dissection. And he stops and checks after every few cuts to make sure he's in the right plane and going in the right dissection. Once complete, circumferential incision is made, and you can see there's good separation of the tissue, and an edge has been made on the side of the submucosa. This allows the IT knife to be able to hook the submucosa layer, be dragged across, and efficiently cut through the submucosa. Similarly for IT knife dissection, we start on the outside of the lesion, working towards the center. And it's important to be able to create an edge and good separation that you're able to find a good area of submucosa to be able to hook on. Next is an example of how to use the IT knife for esophageal ESD. This is a technique that I learned at the National Cancer Center, and is my go-to technique for performing esophageal ESD. So the esophageal submucosa is unique that it is very loose, and it allows the entire ceramic chip to be entered into the submucosa layer. That way, you can cut with the backside or short blade chip, as well as the long blade. And there's less risk of perforation, because the ceramic chip is protecting away perforation. So you can see here, the ceramic chip is buried deep into the submucosa layer, allowing us to cut with both the long blade and short blade of the knife. This technique can be either combined with C-shape incision, or endoscopic submucosal tunneling, that allows for nice, controlled dissection within the submucosa layer. The final example of the IT knife use is, this is using an IT nano-knife in clonic ESD. And this video is actually my mentor in Japan, Professor Yutaiko Saito, performing ESD of a colon polyp with advanced J-neck classification. So a circumferential incision, a traction wire has been used already to expose the submucosal layer. And then you can see starting from the lateral border, the life is pulled across and backwards and very efficiently dissects through the submucosal layer. I find this knife actually pairs very well when you use traction. Here's an area of fibrosis where he's isolated normal tissue on either side of the fibrotic area and use the long blade of the knife to be able to cut through the fibrosis efficiently. So in conclusion, the IT knife works different than a standard needle type knife. It takes a little time to learn how to use it properly, but I really believe it's worth the time investment as it can be a very efficient and safe knife to use. Thank you very much for your kind attention. Ajay, any questions from audience? Go ahead. So when you use IT knife, do you, like, when we're using dual knife, we know that white ceramic tick has to be, you got to be visible. Beyond that, it could be really deeper. Because when you're using IT, a lot of time you're just, all you see is just your white ceramic tip is behind the cutting edge and then you're just moving. Towards the muscle, is there a risk of injury with that or not? And then other thing was that, do you, like, in terms of when you, do you prefer to pull back always or is pushing okay or not? Very good points. And I think you pointed out a good point. During needle type dissection, it's very important to know where your catheter edge is. So you're not slipping your actual catheter into the submucosal layer and dissecting where you don't want to do. So that's, in needle type knife, you're seeing a plane and you're dissecting through it. IT knife isn't the same way. In some ways, you have to be very cognizant about what is the curve of the musculature and you, a 3D thinking of what tissue you're grasping. So the end of the knife is not going to cut anything, right? It's more important about what tissue you're catching with that long blade when you're cutting across. So in some ways, you're going to make an edge on the side of the submucosa, so submucosal trimming, bring the knife in and hook it. But when you're doing that cutting, you're correct. You don't have visualization of that plane. You just have to make sure in your mind that you're at an angle where the muscle would not be. Yeah. I have a memory that when I'm doing it, a lot of times the tissue bunches on me and I'm like, I'm like, essentially traction is supplied by me and it's not cutting properly. Is it, should I use endocut mode more or coag mode? Because whenever I use coag, it just hangs on it and just keeps like there. Yeah, those are two great points. And I forgot to answer one of your previous questions. I generally like to pull and cut with the IT knife. If you have to push, I generally would use a needle type knife to do that cut. I think a lot of the times when I see people use IT knife, they just put it at the border and then step on the pedal and then try to move across. I don't think it works very effectively like that. And please, you guys have much more experience than I do, but I tend to capture the tissue and sort of pull on it like loading a bowstring. And once that tissue is already under tension, then I'll hit the pedal and cut what I've already captured. Do you feel like there's more bleeding with the IT knife because you're not seeing the plane? So when you're ripping the submucosa apart and digging the swing? I think you do have to be careful about the blood vessels and make sure any area that you're cutting, you're exposing well. So if you do have bleeding, that you're able to deal with it. I actually find there's more cautery effect when you cut with an IT knife compared to a needle type knife. So I don't think I'm encountering more bleeding. Thank you very much. Well, just to add to the IT comment, when you are not be able to cut, is it so you keep applying? Are you using coagulation mode, swift coag or dry cut? Probably swift coag, right? I would use coag, but then I use force coag. So in that case, if you're insufficiently touching the tissue and giving a traction or tension, you're desiccating tissue and getting much more resistant. So if that's the case, you may have to change the more cut forward current. However, if you're not cutting well with a force coag or swift coag, you may be touching or trying to cut the vessel. So you have to be prepared that you may see when you cut, you may see positive bleeding. Yes, nobody else is. Peter, you do use IT, right? Yeah, I mean, it's my favorite knife in the stomach and in the esophagus. And I basically, you covered most of the stuff. The only last thing that I will say is that the angle of the knife in relation to the tissue is the key component. You have to be at acute angle, preferably 45 degrees or so. Sometimes you cannot get the 45 degrees angle. But if you're into oblique angle, you will be very difficult to cut. I find actually less bleeding with the IT knife. The blade is much thicker than any other knife, so you get more coagulation. And as Sergei was saying, if I see a vessel coming, I will slow down the movement of the knife and that will provide more coagulation in that area. The final thing is by observing at various workshops, the common problem is too much contact in between the blade, the long blade of the knife and the tissue. So if you're not cutting well, a typical maneuver is actually to pull the knife a little bit towards you, allow for smaller surface area of the knife to touch the tissue, concentrate your current density. And if you coagulate at one spot for a while, you desiccate the tissue, then that makes your cutting even that much difficult. Then you have to switch to cutting current in order to get out of that stuck position and continue with a coagulating current. That's right. And most of the institutions nowadays use swift coag, not the force coag with IT. And Sergei is clearly the exception, using spray for the submucosal dissection and in his hands works well. But the main concern with spray is that you burn the bottom of the specimen and you may end up with a positive deep margin. So swift, forced, precise sec will be the usual modalities that most endoscopies will use. I just wanted to add regarding that comment about the bunching the tissue. It's generally a bad idea. So what happened is that you are forcing the knife to work and you should not do that. You attach and you create your job is to create the contact and then the generator will give you the proper voltage to cut it. And if you are bunching the tissue you are not making it faster, you are making it slower because there is much more resistance in that situation. All you need to do you provide the contact and then let generator to find the setting and do it. And from that point of view also tapping on the pedal may be counterproductive because if you do it too fast generator is not able to get full cycle. Generator runs only like half of the cycle or one fourth of the cycle. So you need to really let it work before you are trying to move forward. One more question for the IT guy. Do you pull the scope or do you or keep the knife like whatever is out is out or you also while you are pulling you are moving your scope to change the knife position as well? Generally during PSD I try to do most of my movements from the scope itself. Sometimes based on the position you might have to adjust the knife. Great discussion. One more question on cost effectiveness. I know you cannot make the initial incision with an IT knife and so you have to use a second knife. With that can you make the initial incision with maybe something cheaper like a snare tip or to try to have some cost effectiveness from that perspective? I think you can. I think in Japan they used to use a different sort of very cheap stick taffeta initially to make that incision. The truth is I think even in most cases that I use an IT knife I do use parts to use it. So it does involve opening two different knives. From a hospital standpoint mostly the argument that I make is for our industry time is money. If some device can shorten our procedure times I think it makes financial sense. The reprocessible needle knife is still available so if you really want to cut the cost you can choose that. If you have a reprocessing that's going sometimes they throw things away. Let's take a 10 minute break. Thank you so much.

IT knife

endoscopic submucosal dissection

ESD procedures

IT 2 knife

IT Nano knife