Okay, thank you for your kind introduction. My name is Yuto Shimamura from Showa University Koto Toyosu Hospital in Tokyo, Japan. First I'd like to thank Dr. Fukami and Dr. Yahagi, NASGJGS, for having me to talk in this prestigious course. I will discuss ESD basic techniques and share some essential tips. Now I have no COI to disclose. This is the agenda of my talk. I will review the preparation of ESD and ESD basic techniques and briefly discuss traction techniques and basic strategies. I'll go over some of the key equipment in ESD. The operator should know what is required to safely and effectively perform ESD. Distal attachment is required in all cases, regardless of the lesion location. It maintains an optimal field of view and allows the application of traction to some mucosal layer for efficient dissection. There are several distal attachments that you can choose from. In our institution, we prefer this new super soft cap for esophageal lesions, but harder cap for gastric lesions, and tapered cap SD hood for duodenal and colonic lesions. How should the distal attachment be placed? If an overpressure evacuation hole exists, it should be placed opposite from the working channel. Also, better not to put it too deeply so that you can directly visualize the working space at 6 to 7 o'clock. I'll briefly introduce knives. It's been discussed already. Distal knife can be used in all situations, from marking to dissection, and it allows accurate and pinpoint tissue dissection and is useful in fibrotic cases. The knife should be moved from the center to the periphery of the lesion and from the near side to the far side, as shown here in the illustration. Insulated tip knife minimizes the risk of perforation. With a long blade, it allows faster and efficient dissection. The movement of the knife is different from needle knife. It should be moved from periphery to the center and far side to the near side of the lesion. There is also a scissor type that has the capability of grasping the tissue, which allows stable dissection. The direction of knife movement is similar to needle knife. This is the image of our operating room. It is essential to have the equipment in the proper place, and CO2 is highly recommended. It is advantageous over air insufflation in the case of unexpected complications such as perforation. Maintaining clear visibility is vital to achieving a high-quality procedure. We feel that lens cleaner and Q-tips, these are must tools for our procedure to ensure clear visibility. I'm not going into details, but with regard to general settings, these are settings for ESD in our institutions. For mucosal incision, we use endocut I. We use forced or swift coagulation mode for the dissection of upper GI lesions. Swift coagulation mode is applied in colorectal lesions. Now we'll move on to the ESD basic techniques. ESD is divided into several steps. One, marking. Two, injection. Three, mucosal incision. Four, trimming. And five, some mucosal dissection. The first step is to mark the lesions, and marking is required in locations where lesion boundaries are difficult to delineate. It is often easier to trace the lesion in the colorectal lesions so that this step can be skipped. However, marking is necessary if there is no clear demarcation. And to assess the lesion, magnifying NBI or other IE chromoendoscopy, such as indigo carmine and iodine staining, should be definitely used. And important tips are as follows. The suspicious area adjacent to the lesion must be included in the resected area, resected specimen, and markings should be placed on the site diagnosed as definite non-neoplasia. And for nearly circumferential esophageal lesions, markings should be placed close to the margin. This is to decrease the resection area, which in turn will lower the risk of stricture. For poorly differentiated gastric lesions, markings should be placed further than 5 millimeters. And also, preoperative negative biopsies can be performed if necessary. We usually use a soft coag in the esophagus and forced coag in the stomach for the markings. The second step is injection. A good needle selection and good injection are mandatory. A sharper needle reduces the puncture force but increases the risk of penetrating too deep. Expanded inner lumen allows high-viscosity liquid to pass through smoothly, but it may create holes that cause liquid leakage after some mucosal injection. So as you can see here, the first puncture force is the most important. Try not to inject too deep or too shallow. If the initial injection is successful, the subsequent injection becomes much easier. We use an injection needle 25 gauge with a 4 millimeter and prefer to use a blunt type needle. It's better to inject just after the markings where the mucosal incision is planned and the needle tip is slightly maneuvered within the submucosa to identify the ideal plane while the solution is injected. And the precise maneuver of the needle tip enables control of the direction of bleb creation up like this as shown here. And also please note that puncturing into the base of the previous elevation makes the subsequent injection easier. And this has been also discussed. There are several high-viscosity solutions available. There are benefits and limitations to each of them. So it depends on the operator's preference. In Japan, I think hyaluronic acid and glycerol are popular solutions used in ESD, especially in the initial submucosal lift. For additional injection, we prefer to use saline with blue dye, applying a jet function of the knife. Although saline dissipates quickly, but it can be added without taking out the knife. In our institution, 5 cc of indigo carmine is added to 500 cc of normal saline to create the blue dye solution. And this video clip shows the advantage of using the knife jet function. You can start the mucosal incision with a small cut, then calibrate the depth of the incision and adjust the depth as you cut. And we can also add injection, and then you can continue with the incision. And I will move on to the mucosal incision. The critical point here is to take sufficient margin around the markings to achieve R0 resection and inject solution into the submucosal layer as needed. And a shallow mucosal incision is made with the endo-cut mode to reduce the incidence of bleeding during the incision. And the incision line is deepened with a coagulation mode and coagulating the submucosal vessels when needed. And the other tip is to take advantage of the submucosal layer identified and continue to dissect that layer. The importance here is to identify the submucosal layer and to use that and to continue. And the next step is a trimming. It is a crucial step between the mucosal incision and dissection. And there are the following reasons. One, it is vital to access deep into the submucosa. And two, completion of submucosal dissection becomes much, much easier when trimming is done at the edges of the specimen. And trimming should be aimed to cut muscular submucosa and superficial submucosal layer. By doing so, small vessels and fat can be cut and cauterized. And as I said, it is imperative to trim the lateral and distal edges of the specimen. And this will make your life much easier at the end of the procedure. Trimming either endo-cut or coagulation mode is acceptable depending on the condition of vascularity and fat. And try to identify the muscularis propria to aim for dissection of deeper layer of submucosa at the trimming stage. The last but the main part of ESD is submucosal dissection. Properly expose the submucosal plane to safely and effectively dissect. And about the electrocautery settings, endo-cut is used in the absence of large vessels to increase precision and speed. The cutting mode also prevents charring. And the most important thing is to always use the distal attachment cap to open up the submucosa. And I think slow and steady dissection is the key to an efficient procedure. And to achieve smoother ESD, it is better to approach deep into the submucosal layer to reduce the risk of bleeding by coagulating the large vascular trunks that branch out superficially. Deep submucosal dissection above the muscularis propria is the key to avoid bleeding and charring. But be sure not to go too deep. This video clip shows large vessels in the gastric wall penetrating the muscularis propria and branching towards the mucosa. And coagulating the larger vessels at the deeper layer is better to avoid unnecessary bleeding. So as you can see in this video, large penetrating vessels are being coagulated. And the other tip to achieve smoother ESD is to utilize the water pressure method. I'm not going into detail with this. Water pressure with jet function opens up the submucosal layer and allows better visualization. This method is especially useful in duodenal and colonic ESD. Now I will briefly go over on traction techniques and basic strategies. Traction devices are generally divided into two types, external and internal. When a lesion exists at a base of gravity and natural traction cannot be obtained, the traction method effectively achieves a good view of the operative field. So do we need traction? I think the answer is definitely yes, as it allows shorter procedure time, improved r0 resection rates, and a lower risk of perforation. And I think the clip-align method is mostly widely used as this is a simple and easy way to achieve excellent traction. So I think this will be discussed later on. Our institution uses this multipoint traction method to control the lesion with a larger surface area. I will present a short case of a large superficial esophageal lesion. And after the circumferential incision, the multipoint traction method was applied. First the snare is grabbed with the repositional clip. And these were advanced and intubated, inserted. And these are deployed. This was deployed at the oral edge of the specimen. And this was continued to deploy three clips to fix the snare to the specimen. Then adequate traction is achieved with better submucosal visualization. And this allows for safer and more efficient dissection. And this shows that the base of the resected area is clean without any muscle injury. And this traction has an advantage when encountering large vessels. Large vessels can be identified as more manageable by using this traction technique. Keeping the traction, this will easily visualize the vessel. And even if it bleeds, it is easier to identify the bleeding point. And it can be coagulated without losing the view because of this continuous traction. The other significant advantage of this traction technique is that the specimen can be pulled or can be pushed so that the ideal sub-mucosal traction can be adjusted. Now loop traction device can be also used as an internal traction technique in colonic ESD. And we can't withdraw the scope for traction, so the loop traction enables good traction and is most useful in the colonic lesions. Here is one example, one case, the loop is clipped to the specimen edge and then the loop was pulled distally with the repositional clip and deployed at the contralateral side. And then by doing that, it shows it achieves the good traction. And this is the last section of the talk. What are the things to avoid during the procedure? One, do not rush, slow but steady progress is better. Book as much time as you can when you're getting started. And do not work far away from the lesion and it should be performed close to the lesion. And also initial incision should not be too close to the lesion as it can cause difficulties accessing into the sub-mucosa. And four, lastly, congestion approach to muscular layer should be avoided. Another thing not to do is to use two hands on the knobs. The right hand should constantly be on the scope shaft for better control. And things to do are to withdraw the scope and clean the lens for better visualization. And clean the needle for a better cut. And air control is the most important thing to do. Always be cautious enough to control how much air you insufflate. I think this is one of the most important things to be cautious during the ESD. The other important thing is to start the mucosal incision from the dependent position. So you always have to consider gravity when planning the strategy. And I will review the basic strategies. First appropriate time booked. Do you have all the tools you need? Is your team familiar with tools, devices? And regarding lesions, where is the gravity, where to start, and how to proceed? And also you have to expect challenges, scope maneuverability, fibrosis, bleeding, fat. And are you going to use traction? And how are you going to manage complications? These need to be reviewed every time you start the procedure. I'm not going into details with the strategies, but there are advanced strategies such as tunnel strategy in the large esophageal lesions. Another representative strategy is the pocket creation method. I think this will be discussed later on. In conclusion, the operator should know what is required to safely and effectively perform ESD. Tips were provided in each part of ESD procedures. And traction techniques and basic ESD strategies should be applied to aim for efficient ESD. Thank you very much.

endoscopic submucosal dissection

techniques

equipment placement

knives

visibility

traction techniques