Okay, so my name is Aris Ahakian. I've got a couple of interesting cases today. We're gonna start with a, oh, here are my disclosures. So the first case is a case of underwater EMR. This is a patient that was referred to me for this lesion that was found in the ascending colon. And I just wanna take a quick look at this lesion here first before we start the video. So what we're seeing here is we see this kind of dominant sessile component here. And if you're not careful, you might actually think this is the polyp, but actually, if you look around it, the polyp is actually quite a bit larger than that. And it's interesting because we see here that there's this really almost depressed-looking part of the polyp here. The polyp is quite large, and then the edge is sort of heaped up kind of like a pie crust, like somebody sort of turned it up on the edges. And what really makes this even more difficult is that you can see that a tattoo has been placed here. And so this lesion has been completely tattooed underneath it. So we already know this is gonna be a fairly difficult resection. If we chose to remove this with ESD, I think everyone can agree it would be very, very challenging to remove this with a tattoo underneath it. So we actually chose to remove this with underwater EMR, which I use quite a bit in very flat fibrotic lesions and makes it much easier, I think, to grasp these lesions. So we've infused the whole lumen here with water, and we're using a 15-millimeter snare, which is often what I use with underwater EMR. And you can see here that this lesion actually comes out really quite nicely with underwater EMR. We're starting to see that darkness at the base, which represents the tattoo. In a lesion here, which I think would be really difficult, if not impossible, to lift, or very difficult to remove with ESD, using piecemeal underwater EMR, we're able to remove this in four pieces really quite quickly with a very clean-appearing resection and a clean base. And you can see the significant amount of tattoo there at the base. Keep in mind, that's not injectate. We didn't inject this lesion at all. And we're able to get a very, very quick resection there on that lesion. And this lesion was benign. This was just a simple tubular adenoma. But because of those other factors, this would have been very challenging, I think, to remove otherwise. Go ahead and move to the next slide here. So this lesion, I'm gonna just go ahead and play this here, and then we'll pause it to look at the morphology of the lesion. This was a lesion in the rectum that was referred to me for resection. And this was biopsied and found to be a tubular villus adenoma. So just to take a look here at the lesion, you can see here that what we have is really a dominant sessile nodule. We would call this a 1S component. But it's important to really look around this lesion because this particular lesion also has a flat, laterally spreading component around it. And so altogether, this lesion is really over three centimeters, and the feeling was this would be very hard to remove on block with a snare. And as Dr. Amit Rastogi nicely introduced and demonstrated earlier, these particular lesions can have occult cancer under this dominant nodule. So one option is to remove this dominant nodule separately, or the other option is to remove this, try to remove this on block with ESD or hybrid ESD. So being in the rectum and being a favorable location, we chose to remove this particular lesion with ESD. And you can see here, we're looking at this with NBI, a very nice JNET 2A pattern there. We're going ahead and injecting here with a colloid injectate, starting our circumferential incision. I generally try to stay about one centimeter margin around the lesion. And you can see here very quickly that we're starting to see a lot of submucosal fibrosis. And this is something I see frequently with these kind of bulky sessile lesions. So we're using traction here, and this is a wire loop device that we're going to clip to the distal end of the lesion, and then again proximally to the normal mucosa. And the curve on that wire is going to give us a lot of traction, and once we have that traction, you can see that the dissection in the submucosa, despite the fibrosis, becomes much easier now and much quicker. And what was a very difficult resection now became a much easier resection. Now with these bulky TVAs, always keep in mind they tend to have large vessels. It's good to try to coagulate these prophylactically. You can actually save yourself a lot of time. Now we're towards the end of the lesion here. Again, we're still encountering fibrosis, but this device has really given us good traction throughout the case. So we were able to fairly easily remove this lesion in under an hour, and we can see here we've decided to close this with sutures because of the tangential orientation. This would have been difficult to clip. But with two running sutures, we were able to close this lesion quite easily. This lesion did end up being benign, and it was found to be a tubulovilous adenoma on pathology. So retrospectively, if you had removed this with piecemeal EMR, you would have been fine, but it is important, I think, to do the right thing prospectively so that when you get in those situations where you do end up with a cancer, you can have nice, clean histological margins to evaluate the lesion. Thank you very much for your attention.

lesion

ascending colon

underwater EMR

rectum

ESD