Hey, good morning, and I'd like to thank the ASGE and our course directors for the opportunity to give this talk. And we're very fortunate in this time that we have such a plethora of ESD tools and devices that we can use. It wasn't just a few years ago that we're really struggling to get the right equipment to perform ESD well in the United States. Here are my relevant disclosures. So very simple, we'll sort of go over all the different equipment that is necessary to perform ESD, as well as some additional equipment that can help you perform these procedures easier. One of the first key pieces of equipment is a simple, clear plastic cap called a distal attachment. It aids you greatly during ESD, as it aids in visualization, because it maintains a distance between the target tissue and the end of the endoscope, so you can get close to the tissue without running out. It also helps in counter traction, and facilitates the scope entering into the semicosal layer, lifting the mucosa, and helping expose the semicosal layer for dissection. Where the semicosal layer is thick, like the esophagus and gastric, we use straight-type distal attachments. But where the semicosa is narrower, tapered distal attachments can be very beneficial in conjunction with water pressure method to help get into the semicosa in duodenal ESD and colonic ESD. There's a variety of knives that are now available for use to perform ESD. The first knife we'll talk about is the needle-type knife. This is really the workhorse knife in ESD, and can be used both in the mucosal and semicosal dissection phase. There are a variety of different needle-type knives that are available from many manufacturers throughout the US. So I originally got these videos from Professor Oda when I visited the National Cancer Center, sort of talking about how to use different ESD knives for dissection. And I think they're still pertinent today. So a needle-type knife works very similar to a bovie. It cuts with the tip of the knife. You can clearly see your dissection plane. And you touch the tissue to be able to dissect through. Here's an example of a needle-type knife during ESD dissection. The semicosal layer has been stained blue with a semicosal injection fluid. And you can see under direct visualization, the needle-type knife allows for precise control and is very intuitive to use, very similar to a pre-cut sphincterotomy that you would perform during ESD, during ERCP. And nowadays, we have knives that have injection capability. This really helps potentially reduce the time needed to perform ESD. Before you would dissect, and if you had to increase your lift, you would have to remove your knife, pass an injection catheter, inject fluid, and then return to your knife. And those device exchanges were eating up quite a lot of time during dissection. With injection capability of the knife, you're able to keep the knife in play, inject into your semicosal plane, and continue with dissection. The next knife that we'll talk about is actually one of my favorite knives. That's the insulated tip knife. It has a ceramic insulated ball at the end of the knife. So it doesn't actually cut with the tip of the knife, but the long blade of the knife. It can extend mucosal incisions, but it cannot create the initial mucosal incision. And as large amounts of submucosa can be hooked with the long blade, it can potentially allow for faster submucosal dissection, as larger amounts can be hooked. So the insulated tip knife works more akin to a scalpel, where the tissue is grabbed and the knife is pulled, cutting with the long blade of the knife. Here's an example of the IT knife used in the procedure. Mucosal incision has already been made with a needle-type knife. It's hooked with a ceramic ball, and then the knife is pulled, cutting with the long blade of the knife. Now, you can see here it allows for very fast and efficient dissection, but you don't always have a good visualization of the dissection plane. The next type of knife available to us is the scissor-type knife. And like the name suggests, the knife works like a scissor. It simply grasps and cuts the tissue between the blades, and can also be used for coagulation of vessels. In a stable scope position, the scissors are advanced through the accessory channel, the tissue is grabbed between the two blades, and is dissected through. And as to use this device, the scope doesn't need to move. So when you dissect with a needle-type knife or an insulated tip knife, the scope has to move laterally. With a scissor-type knife, the actual scope does not need to move. So it works very well with the retraction methods that are dependent upon the scope. So while performing ESD, bleeding is just part of the job. So it's very important to get comfortable at dealing with bleeding during the procedure, and we have great devices to be able to stop that, called coagulation graspers. But it's important to understand that excessive coagulation can make subsequent dissection more difficult to perform. Coagulation cinches down the tissues and sort of has a fibrosis effect on the submucosa. Coagulated tissues are harder to cut through. They can result in carbonation of blood that can interfere with visualization. And too much coagulation can result in thermal damage to the muscle layer and increase the risk of delayed perforation. So it's important to be precise with your coagulation. I'll give you an example here. This is a gastric cardio tumor, and we're making the distal incision in retroflex using a needle-type knife. During the dissection, we encounter bleeding. We continue to dissect because I want to have good exposure to the blood vessel when we come in with coagulation graspers. So we clearly isolate the vessel, and we can see where the bleeding is coming from. We precisely grab it with coagulation graspers. Here's an important step where we're checking to make sure that the bleeding has stopped just by grabbing the vessel, showing us that we're at the right spot. The vessel is sealed with coagulation. The second bleeding spot is found. Once again, we precisely grab the vessel and apply coagulation. And this limits the thermal damage that we're giving to the tissues in that area. Some mucosal injection fluids play a large part during ESD procedures. It is not only how long these fluids last, but also how much elevation that they give. For a while, we used a number of off-the-shelf fluids to perform ESD. We still use many of these fluids today, for instance, like methylcellulose that is commonly found in eyedrops and can be mixed with a dye like indigo carmine or methylene blue to make a submucosal injection fluid, or hydroxyethyl starch, which is commercially available as volvulin or hexastarch, and is also used in combination with dyes. Now we have a number of commercially available submucosal fluids that are very easy for endoscopy suites and nurses to use. They all have their benefits and limitations. Some have issues with bubbling, others with foreign body reaction. So I recommend that you try out these fluids and see what aligns with your practice and what you enjoy to use. So the next section is not necessary devices, but there are devices that can help make these procedures easier to perform. And so one of the major limitations of ESD, or what makes it hard, is it lacks any surgical principles of triangulation. The procedure is done through one endoscope, with an endocap at the end of it, that we essentially try to nudge under a mucosal flap to find to our dissection plane. There's no surgeon secondhand or assistant to lift the tissue up and expose that plane for our dissection. And this limitation has been known for a while, and over the years we've worked on a number of solutions. The first I'd like to highlight is actually a very simple, off-the-shelf technique called clip-line traction. It's very beneficial, it's very simple to use, and has been shown in randomized controlled trials to reduce the time needed to perform esophageal ESD. And this video is actually courtesy of my good friend Citro Abe, who highlights this technique. So first, with the endoscope outside of the patient, and the endoclip passed through the accessory channel, dental floss, suture, umbilical tape is tied to the blades of the clip. The clip is then withdrawn into the accessory channel, the endoscope is advanced into the esophagus, the clip is extended out of the channel, and at the proximal border, either on the mucosa or the superficial submucosa, the clip is placed. Once the clip is placed, the string is then pulled out of the patient's mouth. We normally put a hemostat as sort of a weight anchor to put pressure on the string. And you can see, once the lesion is retracted back, the submucosa layer is much better exposed, and there's tension on the submucosa, which makes it easier to dissect through. The other device that we wanted to highlight was the traction wire that has very recently been fully approved in the US as a de novo retraction device that can be used anywhere throughout the GI tract. This is a device that we developed and designed at the Cleveland Clinic and partnered with industry to help bring to market. It's a very simple device, it's a nitinol traction wire that's curved in its natural state. So once attached to a lesion, it returns to its pre-curved shape, lifting up the mucosa and exposing the submucosa layer for dissection. Here is a short video, and we'll obviously show off these devices more in the lab when you get a hands-on experience. This is a case of a 4 centimeter lateral spreading tumor, granular type with a dominant nodule. Circumferential mucosal incision has already been made around the lesion. A clip is placed at the distal border of the lesion with the traction wire already attached. The wire is then grabbed and placed in the opposite wall, proximal to the lesion. Once the anchoring clip is fired, the wire returns to its pre-curved shape, lifting up the mucosa and exposing the submucosa layer for dissection. In improved submucosal dissection, we're able to perform dissection in the deep submucosa, away from the rich vasculature in the superficial submucosa. It's easy to see blood vessels and avoid them. Dissection is delicately continued around the circumference of the lesion. Large, penetrating vessels can be seen and simply grabbed with coagulation graspers and coagulated. This allows us to keep a very clean and blood-free dissection plane throughout the procedure. The traction continues until the end of the procedure. The final attachments are dissected through. The anchoring clip is designed to be less traumatic. It's grabbed with grasping forceps, gently pulled off the mucosa, retrieving the lesion and the device. There are other retraction devices that are available to us in the market. There is the overtube category. These are very beneficial in clonic ESD. While they take some time to pass and put into position, they can create stability, space, and they offer dynamic retraction that can be changed throughout the procedure. And also, we've got new grasping forceps that can be manipulated to pass through double-channel endoscopes. The grasping forcep through one accessory channel and a knife or scissor through the other channel to be able to do submucosal dissection. We really encourage you to try out these new traction devices. I think they're very beneficial and make ESD significantly easier to perform. Thank you very much for your kind attention.

Endoscopic Submucosal Dissection

ESD procedures

distal attachment

knives

coagulation graspers