to recognize the dissection plane and how to deal with the big artery. So this is a 93-year-old female who had rectal bleeding, and then she had this large mass, probably LSD, granular type, mixed type, very like a bulky mass, and then there's some flat elevated area, like extension of the flat area. Then there are a lot of mucus, which is very hard to remove with water irrigation. So it's close to the dendritic line, probably like a half-circumferential mass in the rectum. And then under BLI, it's hard to tell, but it's mostly type IIa, and then I think this area, I would say, type IIb under genet classification. And then this is a forward view. You can see that it almost extends to the dendritic line. And then we usually start the ESD from the anal side, and then I did the pocket method. And this is during the semi-ucosal dissection. I was dissecting right above the muscle, so this is right underneath the bulky mass, and then I just made a mistake at this point. And then I want to focus on these findings, and then what do you see in this situation? In the fiber? Yes, so you can see that, so on the 12 o'clock, you can see the circum, sorry, circular muscle, right? And then this is the longitudinal outer muscle. So in the rectum, sometimes those like, there's some intermuscular fiber space, and sometimes we intentionally go into the muscle layer. So this is how I ended up going into the intermuscular space. So I thought I need to go back to the surface of the muscle, so I started to inject onto the surface of the muscle right at this point. So this is the right space, so I'm injecting, and I'm trying to go back to the submucosal space. And then at this point, I found another finding. And then what do you see here? Yeah, so this is a huge artery, so this is where the perforating artery came out. So there are two arteries, so this is the larger one, and this is a smaller one, but it's still pulsating. So this is almost at the end of my EST, but I was thinking like, I really wanted to avoid a massive bleeding, so I wanted to ask all the attendees, what would you do at this point? So I just decided to just isolate those arteries, so I can probably do the vestibular sealing before cutting. But I was still thinking what to do deal with these big arteries. So this is like submucosal space, and there are two arteries, so I think there are some options. The probably first option is to just go ahead and cut with the IT knife or like a big, like a EST knife with a large surface area, with a low current density. And then the other option would be to use a coagulasper, and then just cut into it. And then I want to ask Dr. Yahagi, what do you do? I try to use the open tip of dual knife for the smaller blood vessel to seal this blood vessel. Probably I can do it, but for the larger blood vessel, we should use coagulasper in order to make sure the safety. Then even after successful cutting of the coagulated area, I will apply end clip after the complete resection of big region to avoid delayed bleeding. Thank you very much. I try precoagulation by using the low-dose forced coag by the knife itself by complexing manner. For both of them? Yeah, because there's no risk of induced bleeding in this mode. So if the vessel turns white, you can cut it by the knife itself. So basically you're going to use the low-energy forced coagulation? Yeah, to be precise, 0.4 effect by 3 with a multi-flush knife. So of course, three or four times attempt is needed. Wider space should be coagulated with a compressed manner. Still, the vessel doesn't turn white when we change to the coagulasper. But you can try. Thank you. But don't try by using the IT knife, or use a spark-emitting mode. So you may cause massive bleeding. So basically the soft coag or lower-energy forced coag? Yeah, soft coag will be too weak, voltage very low. Thank you. It is very important to observe the pulsation and color of the blood vessel after coagulation. Thank you very much. So, yeah, that's good to know. So I'm still skeletonizing the arteries. And then I wanted to share one picture with you. So this is a picture from Dr. Toronaga's textbook showing the anatomy of the artery. Let me think that you come out. Yeah, so you can see that I think this is a muscle layer here. And then usually the artery originates from the outside, the GI tract, and then penetrates the muscle, and then makes some branches in some mucosal layer. So this is a very important point. So if your dissection plane is too superficial, you will hit a lot of small arteries. But if you go underneath, like right above the muscle layer, you can catch the perforating artery. So I think this is where the muscle separates, tend to separate, and then there will be a perforating artery. So I'm going to show what I did at this point. I was not brave enough to use the knife. And then I was not confident that I can completely stop the blood flow in the artery with the coagulasper. So I decided to use, I'm not sure if this was effective, but I decided to use the clip first before coagulating. So this is the base of the artery. So I used a short clip, two short clips first, with the hope to eliminate the blood flow. And then I used the coagulasper. Do you think this is too much? So in a surgery, we usually do staples to stop the blood flow. And then I'm using the preside sect with the Bio3. And then as you can see here, there's no bleeding. And then after you dissect the blood vessels, you have to see that there's some mucosal layer behind it. And then you can safely continue the dissection. So Dr. Hiro, you said you had initially cut into the muscle also. Do you think if you hadn't cut into the muscle, you wouldn't have seen this penetrating vessel? So yeah, I think it's a separate issue. Because this is a very big artery, I would have seen this area. But I wanted to emphasize that where the artery originates, so there tend to be a separation of the muscle fibers. So we need to be careful when there's a space in between. You need to see the next muscle fiber to reorient yourself. If you cannot see the next muscle fiber, you shouldn't go into the loose space. I wanted to focus on that. This kind of very sick blood vessel is very common, especially at the lower rectum. And this kind of bulky lesion always accompanies this kind of sick blood vessel. So Hiro, I think that was a brilliant idea to just put the clips. I know you put two. Make me think how scared you were. I was sweating at the time. But yeah, I think the design of the usual clips are like it's not made to stop the bleeding. It's like there's some space, so it's not the perfect way to stop the bleeding. But I wanted to be more comfortable. Therefore, it is a good idea to capture some part of the muscle layer together with the blood vessel. Then we can fill the gap between the end of this. Oh, that's a great idea. And also, clips actually prevent the retraction once you cut it, right? Coagulate, cut it. So that has a secondary mitigation process. And it's important to know that the clip accepts the electric current. So you cannot touch it. You cannot get close to it. You purposefully went away from it. That was brilliant. Thank you. So you can see that there is some separation of the muscle fibers where the artery comes from. So this is how it looks during the ESD. And then this is another artery. I think it's smaller. So I think I could have just directly used the coagulasper. But I did this again because this is the end of the procedure. And I wanted to make sure I'm not going to have the massive bleeding. If I would do clipping in this situation, I would include the surrounding muscle layer together with the front muscle. That's a good idea. That is more stable. Yeah, because there's no space between the clip. And at this point, I decided to actually touch the clip with the coagulasper to just make sure I'm going to cauterize the artery itself. But after this, I still had some bleeding. So I did use the coagulasper to make sure there's no bleeding anymore. Sometimes we try to do that to cauterize the clipped area. But rectum is OK, probably, because it's just more forgiving. In other areas, it can cause delayed perforation. So you have to be careful. So I think this is the last. Yeah, so there's a stamp of arteries. And then this is how it looked after the ESD. And then, because this is a high risk for bleeding, I used an X powder to cover this defect. So this is how it looks when you use an X powder. I decided to apply this to the artery stamp. And then, actually, this patient went home on the same day. And there's no bleeding afterwards. OK. So this is a specimen, 10 centimeter. Actually, this was a moderately differentiated invasive adenoma. But the dissection invasion depth was 850. So it was curative resection. Thank you very much. Congratulations. Thank you. That was a great case. So is there any final question or comments to his case?

rectal bleeding

endoscopic submucosal dissection

intermuscular space

artery isolation

curative resection