The talk I'll be giving today is on new technologies for ESD. Here are my relevant disclosures. So I think you can get the theme that everybody's talking about, traction, and how we need to have traction as part of ESD. So one of the limitations of ESD is it lacks any surgical principles of triangulation. The procedure is done through one single endoscope for the endocap that we try to nuzzle under a mucosal flap to get to our dissection point. There's no surgeon's second hand to lift up the lesion and expose our dissection point. And as Professor Fukami elegantly said back in 2013, what we want for ESD is a second hand traction methods. And I agree with Hiro. I think I've used these robotic platforms. They're quite impressive, the speed of resection that you can do with them. But I think there's quite a few barriers until they come to prime time. So we've seen a number of sort of homemade solutions to bring traction to ESD. One of the most common is clip-line traction. It's cheap. It's effective. And in randomized controls trials, it's been shown to have shorter ESD resection times in the esophagus. But many of these homemade solutions are simple, but they're situational, and they can't be used in all cases. For instance, clip-line traction, that the traction is unidirectional and towards the mouth. So it can be used for esophageal or certain gastric ESDs done in retroflexion. The double channel approach doesn't really solve the problem, because the two devices stay coaxial, and there can be sword fighting between the two devices. So in our mind, the ideal traction device would be independent to the scope. So it wouldn't interfere with the delicate motions needed to perform ESD. We wanted it to be simple and familiar. ESD is already complex enough. We didn't want it to add half an hour just to be able to use your retraction device. It should not rely on insufflation, as we like to perform ESD in a deflated stomach. Should provide continuous traction throughout the ESD procedure, and allow for flexible scope positioning, so you can use it anywhere you plan to perform ESD. So I was very fortunate to go to Japan in 2011, to the National Cancer Center, and learn ESD under Professor Saito and Citro Abe. And at the time, I was a fellow, so I had time on my hands. So I was watching procedures and thinking about, how can we potentially make ESD easier to perform? A lot of the retraction devices that we see, which are great, like SOClip or EndoLifter, these are devices that are only available in Japan, and not in the US market. So coming back to the clinic, we developed a very simple device. It's a traction wire. It's a nitinol wire that is curved in its natural state, and one attached to the backside of the lesion. It returns to its curved shape, lifting up the mucosa and exposing the submucosal layer for dissection. So working together with industry, the device was later refined into a single nitinol wire that is curved in its natural state, and can be simply deployed through the accessory channel of a regular endoscope. Here's a short animation of how we go about using it. So markings are made around the lesion. Fluid is injected into the submucosa. And with the use of this retraction device, I find it's best to do a complete circumferential incision before placing the device, submucosal trimming to make sure there's no muscular mucosa holding it down. Then a clip with the device already attached is put on the mucosal edge of the lesion. The wire is simply grasped with a second clip, and is placed on normal tissue distal to the lesion. Once attached, the wire returns to its pre-curved shape, exposing the submucosal layer for dissection. The second anchoring clip is designed to be less traumatic, and is simply pulled off the mucosa, retrieving the device and the lesion. Here's a case of us performing traction wire ESD in a lateral spreading tumor with a dominant nodule in the rectum. Complete circumferential incision has already been made. The device, with a clip, is placed on the mucosal border. The traction wire is then grabbed with a second anchoring clip. The wire is dragged proximal to the lesion, and placed on the opposite wall. Once the device is released, it lifts up the mucosal flap, exposing the submucosal layer for dissection. With the increased submucosal exposure, it allows us to dissect deep in the submucosal layer, so we can avoid the rich vasculature of the superficial submucosa. Blood vessels can be easily identified and avoided. The dissection is carefully continued around the circumference of the lesion. Large penetrating vessels can be simply grabbed with coagulation graspers and pre-coagulated. This allows us to keep a very clean dissection field, and avoids blood, carbonization, and excessive coagulation. The traction lasts until the end of the procedure, where the final attachments are dissected through using an ESD knife. The anchoring clip is then grabbed, and gently pulled off the mucosa, retrieving both the device and the lesion. So we've just completed our first multi-center study, involving eight centers in the U.S. and one in Japan, on the initial experience of performing traction wire ESD. In total, 103 patients were included. The N-block resection rate was 98.1%. The R0 resection rate is 90%. Very importantly, the device only took two minutes to deploy, meaning it did not add significantly to the complexity of the procedure. Thank you very much for your kind attention, and let me know if you have any questions. Very nice device. Any questions? On that robot that you showed, is there a channel that communicates between the endoscopist, or whoever's operating the robot, and the end of the device? Because there are the arms, but how do you pass on the sutures? So that's a good question. So the question was, if there's an additional channel that we can pass the suture through. You have to put it at the back, or the needle. Right, so, yeah, actually there's the channel through, oh no, we can only pass the biopsy, so there's just a straight device channel, but if you need to deploy the curved suture, like a needle, you need to put it through the patient's mouth or something. So that's another, maybe, limitation. Thank you. Yeah, amazingly, that channel that the system has is humongous, up to six meters, right? So you can pass a lot of different things. The ductabats is the traction wire. I found it, it's really bouncy, it almost acts like the rubber. So that's why I put it onto the opposite wall, instead of what you intended to, on the same wall. And you did the same thing. Yeah, it's funny how that happens. We designed it to be on the same wall, but we found that we get much better traction if the anchoring clip is played higher than the lesion. And I think we're just discovering how best to use it. So Professor Saito actually drags the wire proximally, and then places it and does sort of a different type of traction that way. Yeah, I have the same experience. I used that on the same wall. It works okay at the beginning, but at the end, the end part becomes difficult. So I think the opposite wall is better. Yes. Yeah. Thank you. I'll be in the back, next to you. So it comes in 25 millimeters and 35 millimeters. But it doesn't need to, because you're taking it to the opposite wall, it doesn't need to be the entire length of the lesion. And to follow up on your point, what we found is, if you do it on the same wall for a large lesion, it folds on itself at the end, making that last part of dissection hard. So quick question. I think the key part in the wire also is not to have too much tension on it when you attach it to the opposite wall. Is that right? Absolutely. So I think there's a tendency that you want to overstretch this to give it as much traction as possible. And actually, that kind of distorts tissues too much. If you just pass it a few centimeters beyond the lesion, it allows it to naturally curve up and use the wire technique. Amit, I have a question. Is the second clip or the point of attachment reposition or in any way pulling the clip that you put and placing a second clip at a different location? Yeah. I think that's one of the parts that they want to work for the next generation, Peter, is sometimes, especially during dissection of a larger lesion, the direction you need traction might change during the procedure. One way is you can actually grab the wire with a second clip and place it on a different part of the wall, and that changes the traction. Do you see a point where the lumen is going to be almost completely decompressed so that when you insufflate then? So this is a very good point about insufflation. So this device really works independent to insufflation. Because of the curve of the wire, it will work even if the wall is close or far away. Versus maybe like SO clip, I think changes with insufflation or rubber bands. All right. There was the online question for Dr. Ehaghi. So can the water pressure method be used in the stomach? Yes. As far as the lesion is located, the gravity side, we can use water pressure method even in the stomach.

traction devices

endoscopic submucosal dissection

ESD procedures

clip-line traction

curved nitinol wire