Welcome back, I'm Naoki Sayahagi from Keio University. I'm going to show you how to conduct ESD using DualKnifeJ. Currently, I'm working together with Dr. Kato, also coming from Keio University. He is the chief of the endoscopy unit, and Prof. Toyonaga is giving us a comment during my procedure. Well, I already put a marking dot as an artificial target region, and I selected a relatively difficult area, which is the gravity side. Therefore, I would like to show you how to remove this kind of difficult region using a traction method for the proximal one, and using the water pressure method for the distal one. Well, before conducting actual mucosal incision and submucosal dissection, I would like to inject solution to the submucosal layer. There will be some fibrosis at the G-junction, so I would like to use a little bit viscous agent, which is endocrine, provided by Olympus. Currently, I'm inserting the injection needle, and this is the device which we can inject very viscous agent. Otherwise, we cannot inject this kind of viscous agent. Open it, please. So in this situation, I'd like to give submucosal fluid cushion at the anal side first, checking the edge of the marked area, then insert, make a puncture a few millimeters outside the marking dot, which is on the assumed incision line. Okay, injection, please. Because it has some risk of having bleeding during submucosal injection, that's why I always locate the injection site a few millimeters outside the marking dot. Then if there is some bleeding, we can cut there and stop the bleeding. Okay, injection a little bit more. It's really nice. Oh, okay, stop it, please. We can create a really nice... Like mountain. Yeah, like mountain. Yes, that's right. Then we can inject around here. Okay, injection, please. Okay, stop. Currently, I'm controlling both up-down and right-left channel together with my left hand. Therefore, I can use my right hand to control the seesaw of the injection needle. Injection, please. Okay, that's good. Slightly go to the oral side. Hi. Yes. Okay, stop. Checking the nice lifting sign. Injection, please. Okay, stop. Really nice. And using down angle, I would like to make a puncture at the outer side. Okay, stop it, please. The power of lifting is quite strong because of the viscous nature of the solution. Okay, injection, please. Oh, surprising. Jumping up. Okay, stop. Injection, please Okay, looks good enough. Okay, that's good. Needle in. It's really nicely lifted up. Do you know what solution the actual solution is? Endocrine is a kind of starch. I don't know. Polymer? Polymer. Synthetic polymer. Okay Absorbable. As if it remains in the stomach, it can be absorbed. Okay, that's good. Okay After checking the smooth movement of the endoscope, we can start the causal incision. Because I'm planning to use traction device, I would like to make a circumferential causal incision at the beginning of the procedure. Okay, knife out. And it is always very important to check the cleanness of the knife tip. If it becomes dirty, it doesn't cut well. Therefore, we should check the cleanness of the knife tip all the time. Now we can see the clean tip of the metallic part and gently touch to the target mucosa and press the foot pedal of the cutting current. Now, this is the endocut eye effect 1 and Duration is important. Now, duration 2 is okay, right? Yes, duration 2 is okay. Because dual knife has higher current density, that's why it's easy to cut. Because of the thinner electrode. Now, the white ceramic tip stays on the surface. It is very important. And keeping this distance, I can easily control the direction. By stepping the foot pedal intermittently and checking the direction and recognizing the marking dot, I can easily make a causal incision. And slightly pushing forward. Now, I'm controlling both up-down and right-left channel together with my left hand and controlling the shaft of the endoscope with my right hand. And slightly pushing forward to the inner side, I can easily make a smooth mucosal incision. But it is mandatory to keep the white ceramic tip on the surface. Otherwise, it doesn't cut well. By the way, this is 2mm dual knife J. It is good for gastric ESD procedure. By torquing my wrist and using down angle together with right-left channel, I can easily control the direction. Okay. Then, move back to the outer side and catch the edge of the incised area with the metallic tip of the dual knife. Then, go to the other side. We can make a mucosal incision by pulling back manner. But usually, making incision by pulling back manner tends to go deep. It is a little bit dangerous. That's why I prefer to make a mucosal incision by pushing manner from proximal side to distal side. It is much safer. Okay, giving the same pressure to the target tissue, I can make a nice mucosal incision like this. And check the incision line. Yes, coming very close. Insert the tip to the mucosal edge. Then, connect the incision line. I'm slightly torquing my wrist. Then, I can easily control the direction. Although I'm not twisting the shaft of the endoscope, I can easily control. Then, next step is to trace the inner edge of the incised area with the coagulation current. Because there will be some vascular network within the submucosal layer, therefore, I usually use coagulation current for the submucosal dissection. Tracing the inner edge of the incised area in order to separate the edge of the incised area from the surrounding tissue. Especially at the inner side, it's very important to trace the inner edge. Otherwise, it becomes a little bit difficult to finish the submucosal dissection. By utilizing the limb of the transparent hood, we can check the separation of the tissue from the surrounding tissue. Still, there is some fibrotic tissue remaining here. Therefore, I want to trace this area once again. Now, it is completely separated. It is a good situation. Then, I would like to make initial dissection at the oral side. It is important to have enough space to apply the clip and line traction. Therefore, I would like to dissect a little bit more at the oral side. But it's all the same. We don't have to go too deep. Just trace the inner edge of the incised area with the tip of a dual knife. That is usually good enough. I traced this area only twice, but it already became a nice situation. Okay, it's good enough to apply clip and line traction. Okay, sucking air and avoiding a smoky situation. Then, my assistant, Dr. Kato, is preparing the clip and line traction. It is quite a simple technique, which we usually use just a standard end clip together with dental floss. This is an Olympus reloadable end clip, and I usually use short-sized Olympus easy clip. And inserting the tip of the outer sheath to the cassette and open and close, then we can load the end clip. Okay. Then, insert the end clip to the working channel of the sendoscope. And touch the tip of the end clip and ask my assistant to open it slowly, slowly, not fully. Partially push out. Much more, much more, much more, much more, much more. Okay, that's good enough. Now we can see the metallic part of the end clip and hold here like this. Then, Dr. Kato can make a knot on the metallic tip of the short-sized end clip. He made a loop and hooked it to the metallic part and make a knot. Once more again, please. Oh, you look like a surgeon. Yes. Okay, then, yes, then cut the tail of the tentacross. Okay, it's ready to use. Pulling back the end clip to the cap and hold the line and shaft of the endoscope together. Because you want to pull back the device into the working channel, that's why you didn't open it. Yes, in order to pull back the instruments, at least into the cap, to avoid a risky situation. But to open the clip, there is some risk of it missing because it's very floppy. If you set the clip before the knot, it is very stable. Even after the set, please cut here. Cut here. Leave it, leave it. Even after opening, the clip can be inside. Inside the cap. If you vent, the clip will be easily... Ah, this sometimes happens. I want to avoid this embarrassing moment, that's why. So next, shall we try that? Yeah, okay. Next one, please. Oh, we can use this dental floss again. Again, okay. This one. Let's remove this. So... The other side, okay. Open it. Oh, this is the tape, okay. Please set. Okay. Open it, please. Okay, following Dr. Toyonaga's advice, I already opened the end clip, then make a knot. It doesn't bend. Yes. It's stable. Okay, making a loop and hook it to the opened metallic tip and make a knot. Nicely tied, and cut the tail of the dental floss, okay, it's ready to use, and putting back into the cap, okay, a little bit more, okay, and that will be very stable, and bring back to the stomach, and in separate air to recognize the edge of the dissected area, now we can see the edge, and it's ready to use, push for the endoclip and catch the edge, and check the backside, okay, please fire it, okay, nice, now we can see the line here, and giving tension by grasping the line with the surgical clamp, and let it down as an anchor, and using this surgical clamp as a weight, and most important technical tip is to go below this area, utilizing the upper limb of the transparent hood, we can easily open the submucosal space, now we can visualize the submucosal layer nicely, and check the both side, inflate air a little bit more, then we can widely open here, still there are lots of injected solution here, so it's not necessary to give additional fluid cushion, open it please, and check the edge, and hooking the tissue here, and going to the right side, sometimes it becomes a crappy situation, but don't worry, just go slow, just go slow, and there will be blood vessel here, so stay here, and not to go quickly, and step the foot pedal of coagulation a few times to coagulate blood vessel completely, then we can avoid the bleeding situation, then going back to the left side, and below the line, and check the submucosal tissue, now left side is okay, and hooking this edge, and going to right side, slowly, slowly, it's usually good enough, and white ceramic tip should stay on the surface of the target tissue all the time, unfortunately we don't see so much fibrosis, yeah, because fortunately, I wanted to see your technique for the fibrotic target, but it's okay, okay, for me, unfortunately, now the remaining submucosal tissue becomes quite small, but we should focus on the edge of the remaining tissue, initially I would like to dissect the left side, and remaining submucosal tissue becomes narrower and narrower, and because of the viscous nature of the injected solution, sometimes the lens of endoscope becomes dirty, that's why I flush the lens using the water irrigation, maybe right-hand side we can see the penetrating vessel, yes, that's right, maybe this is tiny blood vessel, therefore by catching here, if there is a really sick blood vessel, I usually use Dr. Toyonaga's special seeding technique, which we usually use very low current of first quark, I usually use 0.3 of first quark in case of finding a blood vessel, but this time there's no blood flow, that's why I can go with the swift quark, okay, checking the edge, and if there is no vascular network, I can just go here, and go to the other side, and it becomes narrower and narrower, and next I should focus on here, and dissect only this side, and remaining tissue becomes narrower and narrower, and by flushing the normal saline, I can recognize the remaining tissue, by catching the edge, I can easily make dissection, now we can see the back side of the remaining tissue, and it is connected, it becomes a little bit crappy situation, in that moment, maybe reduce the tension, yeah, yeah, the weight was too heavy, that's why it was retracted too much, now we can see the nice remaining submucosa tissue, I can recognize the edge of the remaining tissue here, then easily dissect the remaining tissue, gentle movement is usually good enough, we don't have to hurry, now it's completely resected, and it is safe, and a little bit, intentionally, he performed the slope, and retrieval of resected specimen is also very easy, like this, like fishing, yeah, okay, it was very, very steady, yeah, thank you very much, for the next, I would like to show you the water pressure method, to resect the target region, located at the gravity side, therefore, I would like to remove the straight cap, and attach the ST food, coming from Fuji, yeah, they've got, okay, clean-up lens, please, okay, and it is very important to clean the lens all the time, to have a clean view, and attach the, okay, because it has a slit within the tapered tip, therefore, we should insert the instrument to the working channel first, and align the slit to the instrument, and we should check the smooth passage of the instrument, when we use this ST food, now, instruments can pass very smoothly, okay, that's fine, do you need the tape, or, it's not necessary, okay, I don't think so, it's okay, okay, then, go back to stomach, and this time, I would like to conduct the water pressure method, that's why, I completely suck the air, then, fill the lumen with the normal saline, oh, it becomes a little bit dirty, so, just clean the lumen, okay, it is very important to clean the lumen, before starting actual procedure, a question from the audience, when for coagulation of the blood vessel with the coagulasper, is soft or forced coagulation, which is better, for the actual, for coagulasper, yeah, for using coagulasper, soft coagulation mode is the best, I usually use soft coag effect 3, that is usually good enough, breathes fresh air, but maybe, I don't try it yet, but maybe low power force coagulation also can be used, but usual force coagulation for the forceps is not recommended, because it emits a spark, and it has some risk of the chart, induced breathing can happen, yeah, and also, maybe, the adhesion is too much to the coagulasper vessel will be, so, soft coagulation is the best choice for the coagulasper, and for the hemostasis, using Pro-Tip Dual Knife, I always use Spray Coag 1.2, and the vessel sealing, I always use Forced Coag 0.3. Okay, for the water pressure method, we should make a circumferential mucosal incision first, therefore, I would like to inject a large amount of solution to the submucosal layer, okay, needle up please, and recognizing the marking dot, and check the smooth movement of the endoscope, it is okay, then approach to the inner side, and puncture the area a few millimeters outside the marking dot, then start the injection, okay, injection please, okay, that's good enough, is this serine, or colored serine, now, Professor Kato is injecting the serine with some color, it doesn't seem to be the endocannabin, but okay, because we can easily open the submucosal space using the water pressure, that's why, no, such, yeah, we don't need such a viscous agent, okay, and also the Professor Saito mentioned underwater situation create a higher lifting, as if you are injecting serine, yeah, that's right, so they are performing injection underwater EMR, okay, that's good enough, this also seems to be mountain, yeah, we can create a very nice submucosal fluid cushion, maybe you can well compare with the insufflation injection we have done in the first or second case, but much more higher lifting is coming in underwater situation, this is one of the great merits for the underwater procedure. That's right. In case of insufflating air, too much protolusion will be flattened. Also, I have noticed the underwater incision, the smaller opening of the cap is better, because the soft mucosa is coming inside the cap, if you use a straight one. Okay, that's good enough. Also, in case of using a straight cap, the length of the cap looks much shorter in the underwater condition. That's why it sometimes becomes impossible to recognize the lower edge. Therefore, I prefer to use esti-food for the water pressure method. For the water pressure method, I really want to quickly make a submucosal dissection from the oral side. That's why I would like to start the mucosal incision from the anal side in this situation. As I mentioned, making a mucosal incision by pulling back mana is sometimes a little bit dangerous, but if we carefully check the situation, it will be okay. Just making a small hole, now we can see the blue color of the submucosal layer. That means the electrode already penetrated through the muscular mucosa and going into the submucosal layer. Fixing the metallic part within this small hole, I can start the mucosal incision. Usually, it will create lots of bubbles within the underwater condition. Therefore, if it is necessary, we can flush away the bubble by giving additional water irrigation. Now, the ceramic tip is staying on the surface and I don't give too much pressure to the target tissue. That's why it is a relatively safe situation. But if we give too much pressure, it will be a little bit dangerous. Right after making the initial mucosal incision, I just trace the inner edge of the incised area. So, a question from the audience. If doing underwater EMR, is it necessary to inject with water, maybe saline? Oh, no. For the underwater EMR technique, it is not necessary. The merit of underwater is that you can do it without injection. Yes, that's right. But still, in some cases, we sometimes inject a small amount of saline or some viscous agent. The drawback of the injection EMR is that it stretches the region and the region becomes larger. That's why the on-block reaction rate is coming lower. But in the underwater condition, the mass layer can be stretched. That's why the perforation rate is very low. It's a safe procedure. But you can combine it with the injection, even performing EMR under water conditions. Yes, especially the region located beside or on the haustral hood. We usually inject a small amount of solution to the sub-mucosal layer. Also, as you have already seen, water doesn't spread so well. It can create a mountain-like lifting. That's why you can minimize the injection volume when you perform the underwater injection EMR. Yes, that's right. So, just a little injection may work well. Yes. Professor Kato is performing the partial injection underwater EMR, right? In the underwater EMR, you can see the distal side of the region. So, in this case, it completely keeps the resection. To include the visualization of the distal side, we only inject the solution to the distal side. The distal side is the most risky for the vertical EMR. Now, I made 90% of the mucosal incision. Only the proximal part is remaining. Then, I can catch the edge of the incised area with the metallic part. Then, complete the circumferential mucosal incision. Have you intentionally left only the oral side of the mucosal incision? Yes, I usually leave the oral side until the end of the mucosal incision. Then, quickly start sub-mucosal dissection by tracing the inner edge. After tracing the inner edge two or three times, it's time to use the water pressure. I already traced here two times. Then, give the pressure of the water. We can easily open the sub-mucosal space. This is a great merit. The number of traces can be minimized in the underwater condition. That's right. We can easily open the sub-mucosal space, which is usually the most difficult part for the beginners. Right after going to the sub-mucosal space, we should dissect the oral side quickly and connect to the lateral side. Then, it will completely open like this. This becomes a completely safe situation. Check the vessel network and some fibrosis. If there is nothing, we can go quickly. Catch the edge and go to the right side. Go slowly, slowly, torquing my wrist. I don't control the shaft of the endoscope. I just hold it here. Still, I can control the direction. Just torquing my wrist and controlling the up-down channel is usually good enough. Now, we can see the right edge. Hook this area and go to the right side. Check the edge again. Catch this edge and go to the left side. Then, flush away the bubbles. Check the left side edge as well. Hook this edge and go to the right side. Slowly, slowly, but precisely. It's the same as Dr. Toyonaga's procedure. We should check the edge. Probably, this will be the blood vessel. I would like to switch to the first quark, 0.3. No? Just a moment. Not yet. Okay. Now... Low force is good. It's okay. This is first quark, 0.3. That means it doesn't emit spark. We can hook the visible blood vessel with an open-tip dual knife. Then, coagulate it until air bubbles come. Now, we can see the small bubbles. Then, usually, I can hook it from the other side in order to make sure the safety. After turning completely whitish, we can cut here. Please return to the swift quark. Then, hook from the outside and cut here. This is completely safe situation. Usually, we can avoid bleeding situation. Then, check the edge again. This is left side edge. Left side is okay. Then, control the direction. Slowly, slowly twisting wrist and controlling up-down angle. Check the edge again. This is right side edge catching here. Controlling direction to the left side. I don't control the shaft at all. I'm just holding here like this. Still, I can control everything. The right hand is just gently holding the endoscope. It is nearly the end of the procedure. Usually, this kind of region located at the gravity side is quite difficult. Because we cannot open the sub-enclosure space. By utilizing the water pressure method, it is relatively easy. Now, we can see the end point. Hooking the edge. And finish the procedure. This is water. Usually, we can retrieve this resected specimen by sucking the region to the cap. This is a very simple procedure. Thank you very much. If you have any question, please feel free to ask us at any time. Finally, after sucking the liquid, we can check the exposed blood vessel. If there is an exposed blood vessel, we can coagulate the blood vessel using the cross-tip of a dual knife. In that situation, we should use 1.2% of spray quark. It is a very low setting, but usually works very well to coagulate the exposed blood vessel. If this is a blood vessel, I can touch here and coagulate here. Gently touch to the exposed blood vessel. Then, stepping the foot pedal of coagulation a few times. Do you perform this technique usually in an underwater situation? We can use this technique both underwater and under CO2 gas condition. Which is better? It's all the same. Of course, the coagulation effect is a little bit stronger in the CO2 gas condition. Okay, looks fine. If you don't have any question, I would like to finish this session. Thank you very much. So far, no question. Thank you for joining us.

DualKnifeJ

endoscopic submucosal dissection

ESD

viscous agent

mucosal incision

coagulation current

clip and line traction

water pressure method