Okay. Welcome back. For those of you who are just joining in, we've just finished the first session of our EGD masterclass. The EGD masterclass has focused on esophageal strictures, eosinophilic esophagitis and gastric malignant and pre-malignant lesions. So Dana Early just gave us a wonderful masterclass on esophageal strictures. And now it is the turn for Iko Hirano. Iko is professor of medicine at Northwestern University and session two is going to be focused on eosinophilic esophagitis. Iko is going to start off initially with EOE, endoscopic assessment and dilation to be followed by EOE diet and medical therapy back to back. So Iko, if you can have your camera on, we can see your slides. And Iko, of course, is one of the masters in eosinophilic esophagitis, has been part of several guidelines as well as several white papers related to that. So I'm going to be talking about EOE, my favorite topic, my favorite disease. And we'll start off with endoscopic assessment and dilation. And this dovetails really nicely with Dana Early's talk about strictures. So there's going to be some content overlap, but I'll try to keep that to a minimum. So to cover this topic of stricture management, we're going to look at how to best assess strictures. And again, Dana really covered this really well. There are some peculiarities to EOE, so I'll discuss that and focus on that. Then I'll talk about what we talk about when we talk about a conservative dilation approach. And just to call out, there was a recent ASGE consensus statement that was put out by Seva, Pratik Sharma, and others in the EOE world about endoscopic assessment and dilation in EOE. So a lot of things are being referenced there. The third topic I'll talk about is stricture dilation. Is it really effective and safe? And we'll look at, quickly, some of the data there, and I think all of you know the answer to that already. So we talked earlier today about methods to assess strictures, and I think that was one of the Q&A questions about particularly proximal strictures. And Dana talked about using a barium esophagram, particularly the barium tablet. We have endoscopy that we use a lot, and that's kind of our mainstay. I think the esophagram is really, in a lot of places, gone by the wayside, and I think that's a shame. There's a lot of value to barium esophagrams, and endoscopy has a lot of pitfalls. Impedance planimetry, or FLIP, is really coming on the scene, and it probably is the most accurate way to determine strictures. It's expensive and time consuming, but it probably is the most accurate way we have to detect even subtle strictures of the esophagus. And then the fourth approach is to shoot first and ask questions later. That's just to do a dilation and see what happens from your dilation, which we heard about earlier today. So endoscopy, something near and dear to my heart, the system that's been developed and validated now in multiple studies around the world, is called EREFS, which is an acronym that stands for the EOE Endoscopic Reference Score. EREF conveniently is an acronym that also stands for the five major endoscopic features of EOE that include the edema, rings, exudate, furrow, and stricture formation. You can see here some of the gradations of the severity of the different characteristic features that you can detect endoscopically. Now, what about EREFS? There has now been, again, these studies both in Europe and the US, and now another study done by Chris Ma that showed a high degree of intra- and intra-observer agreement for EREFS using classification of EREFS. Endoscopic activity measured by EREFS has now been shown to be a major determinant of what physicians, particularly gastroenterologists, consider to be more severe disease. EREFS has also been associated with food impaction risks as well as symptom severity using validated PRO tools. And in terms of accuracy, both in terms of sensitivity and specificity, there's been a high degree of accuracy shown for endoscopic assessment of this disease, both in children and adults with eosinophilic esophagitis. The fidelity and accuracy of EREFS has now been shown in prospective studies. In fact, there have been now over a dozen placebo-controlled randomized trials that have shown that EREFS works to detect meaningful changes in endoscopic activity using medical and dietary therapies. And it's become an important secondary endpoint of clinical trials at this time. Now, what about endoscopy? One of the pitfalls for endoscopy in the assessment of EOE is strictures. Endoscopy, again, we use it all the time. And one of its major limitations is stricture determination, both in terms of detection and accuracy to determine what the stricture caliber is. It becomes very obvious when the scope gets stuck in the esophagus or can't traverse a stricture. But when you have more subtle strictures that are greater than the diameter of the endoscope, it can be more difficult to determine the presence or the diameter of the stricture. This was nicely shown in a study done by one of our GI fellows, Matt Nelson, who looked at this and compared radiographic analyses with endoscopic assessment using EREFS. And what he nicely demonstrated was that endoscopy is clearly superior for detecting the inflammatory features of EOE. Endoscopists can detect the edema, exudates, and furrows of the esophagus to a much greater degree of sensitivity than a barium esophagram. However, when it comes to the esophagus, these are better detected under fluoroscopic imaging. You can see here, I've highlighted this here. So 40% detection of strictures with endoscopy compared to a 59% detection with fluoroscopic barium esophagram. I think even better highlighting this was this nice study done by the Mayo Clinic group, by Jeff Alexander, Dave Katska, and Jen Thiel, that, again, compared a very careful systematic radiographic imaging protocol where they measured the caliber of the esophagus at different points and compared it to the endoscopic reports from the Mayo Clinic esophageal team that was looking at the endoscopic detection of strictures. And you can see here that for strictures of less than or equal to 13 millimeters, the endoscopic sensitivity for stricture determination was only 33%. And that's a pretty shocking number that endoscopists are missing two-thirds of strictures that are 13 millimeters or less as determined by a barium esophagram. And I think none of us would argue that a 13-millimeter stricture is clinically relevant. So the overall take-home point here is that given the limited sensitivity of endoscopy for the detection of strictures of the esophagus, additional testing, whether it's by an esophagram with a tablet, preferably, or impedance planimetry, the FLIP technology, or, again, the shoot-first-ask-questions-later approach by just doing graded esophageal dilation, should strongly be considered for EOE patients, but particularly those who are persistent symptoms following successful medical or dietary therapy. Now, Dr. Early spoke earlier about focal strictures, the Schatzky ring, or peptic strictures. And these are examples of Schatzky ring. And I would challenge you that it can be very hard to determine accurately the diameter of that stricture. We know that Schatzky ring or distal strictures of the esophagus that are greater than 20 millimeters really should not be causing symptoms of dysphagia or food impaction. So a great way that I teach all our fellows to assess stricture diameter, which is a lot cheaper than doing, you know, impedance planimetry, is to use retroflexion. And this is not just for Schatzky ring, but also for distal strictures from peptic strictures or distal strictures from Eocenophilic esophagitis. Carefully retroflex. Make sure that your scope gives you that 180 or more degree inversion. And if you can do that, retroflex up across the cardia. It's easy when there's a hiatal hernia, not as easy when there's not a hiatal hernia. But you can very accurately determine the diameter of the distal esophagus by comparing it with your scope. Because you know the scope diameter, you just compare the stricture diameter to the scope diameter. And you can very accurately determine, is that a 10 millimeter, a 12 millimeter, a 15 millimeter? In some cases, a 20 or 25 millimeter EGJ stricture. If it's 20 to 25 millimeters or greater, there's no reason to bother doing a balloon dilation of the distal esophagus. Now FLIP again, coming onto the scene, the new FLIP technology, FLIP 2.0, that gives us a very careful topographic mapping of the esophagus. And that can help you detect these proximal, more subtle, diffuse narrow caliber esophagus, or subtle strictures of the proximal esophagus that can be very difficult to detect endoscopically and sometimes can even be subtle on radiographic imaging. Again, it's not ready for prime time yet. It's an expensive technology, but I think it may be something that we see used more in clinical trials to more accurately determine the presence of strictures and also the response of that stricture to medical or dietary therapy. Now here we're going to see an example of a esophageal dilation being performed at the distal esophagus. This is obviously a TTS balloon being inflated across the EGJ. Now, as much as people talk about looking through the balloon, it's not as easy as it sometimes sounds here. You really have to get rid of that air interface. I'm putting a little bit of water into the esophagus, which does introduce some risk of aspiration. But even with water insufflation of the lumen and pulling the balloon back across the esophagus into the scope, it can be very difficult to see what's happening. So after I've done the dilation of the EGJ in an EOE patient, what I do next, and you'll see that being performed here, is I pull the balloon back. And what I'm doing by doing that is to make sure that I haven't missed a stricture in the proximal esophagus. So that balloon inflation, you know you've dilated that balloon to, let's say, 15 millimeters. And as you pull it across the esophagus, you can compare the luminal diameter to the esophageal diameter. Here the esophagus is probably about 18 to 19 millimeters in diameter. So you can make sure that you haven't missed a subtle proximal stricture. Of course, if you get a lot of resistance, you may not want to keep pulling because you may start to cause more and more of a mucosal tear. So this can be used as a way to dilate proximal strictures, but I use it more commonly just to detect whether or not a subtle stricture is present of the esophagus. Now we're going to see here what we obviously cause here is a disruption of the esophagogastric junction. There's about a one centimeter long tear of the EGJ. The scope can now easily traverse the EGJ junction. There's a little bit of bleeding, which you would expect. So that's a successful dilation of an EGJ stricture of the esophagus. Now I want to show you the same patient on pullback what happened here. I didn't notice this when I did the initial endoscopy. Now watch here. Hopefully this is the second. Okay, now I'm pulling back the scope now after I've done that TTS dilation. Now you're seeing there's not really any injury here in the mid esophagus. The proximal esophagus looks pristine, but you'll notice here right at the esophageal inlet there's a spiral fracture. So that's something I didn't really appreciate on endoscopic. And, you know, when I looked at the esophagus and inspected it, I didn't notice that there was a very subtle proximal inlet stricture. It only became apparent to me because I did the pullback technique and I looked after doing the dilation. So an example of a proximal inlet stricture that was very easy to overlook. And this comes up, I see this at least once or twice a month, patient had a balloon dilation done and they said they didn't feel better. And the reason they didn't feel better is because there was a proximal inlet stricture that didn't really get addressed by a balloon dilation of the distal esophagus. Now here's, let me see here. Here's another example here, EOE patient. Endoscopically, you can see edema, you can see some furrows of the esophagus. The esophagus here looks very pliable. There's a nice cardiac pulsation there. And again, I, with my eyes here, I see some very subtle rings of the esophagus, but I really don't see any significant stricture of the esophagus here. I'll let that play through a little bit here. You can see a very, again, very pliable, compliant esophagus. Very hard to detect whether or not there's a stricture here. Again, you could argue with me that I'm not showing you a good insufflated view of the EGJ. But let me show you what happened in this particular patient with a savory dilation of the esophagus. So we're going to go forward here. And here's what the esophagus looked like after a 42, 45, 48. I guesstimated the diameter here was about, you know, 14 millimeters. So I started with a 42 French savory dilation, and I didn't feel any resistance whatsoever. So I went to 45, and then I did a 48 French. Again, no resistance to the passage of a Bousy dilator. And let me show you the result here. It looks a bit like a war zone. So there's a lot of blood here in the esophagus. I do a very careful inspection of the esophagus. After I start to feel some resistance, or after I passed somewhere between two to three dilators, I'll go back down and inspect the esophagus. You're seeing a fair amount of heme here in the esophagus. And after I want to clean up that heme, do a careful inspection of the esophagus. There's a little bit of a tear here, a disruption at the EGJ. But the more significant disruption here is about a 10 centimeter fracture of the esophageal mucosa that goes on from the mid-esophagus all the way up to the proximal esophagus. Again, I wouldn't have really appreciated that by tactile feel of the esophagus. So that's a very long, linear tear of the esophagus caused by a savory dilation of the esophagus. So again, the idea here is that that, you know, subtle stricture got detected through after dilation. Now, what do we mean when we talk about a conservative dilation approach? You hear that talked about, Joel Richter and others have written about conservative dilation for EOE. So these are a couple of practical tips. And again, this is something that I wrote about a few years ago, but it's even highlighted in even greater detail in the ASGE consensus recommendation that was just published a few months ago. First authors, Aceves, A-C-E-V-E-S, and Pratik and others were involved with this. But here's a few practical tips. When you're talking to an EOE patient, it's important that you outline for the patient that this may take several dilations. If you have a patient starting off with a very narrow caliber esophagus, their esophagus is 10 or 11 millimeters, you should tell them it's not going to be one time and done. You're going to need about two to three dilations to get them to the target diameter of 60 millimeters. That way they're not shocked when you tell them after the end of the procedure that they have to come back again in a few weeks. Secondly, review the reported risks of perforation. And you can quote your own center's risk of perforation or quote the literature, which is under 0.5%. You should discuss with them the dilation pain. 75 plus percent of patients who have EOE dilations will experience significant oedinophageal chest pain. And I always counsel my patients that it's going to be painful. That way, when they have the pain afterwards, they're not surprised or shocked. And third, consider analgesia post dilation. I've moved away from narcotics a lot. I find that most patients can be managed by just awareness of Tylenol. But in some cases, narcotic analgesia can be helpful using a Tylenol liquid, a Tylenol coating liquid preparation. Obviously, you don't want to give these patients tablets, particularly for very tight structures. For technical considerations, you can use balloons. Dana presented that information earlier that balloons and savers are probably equivalent. But if you use a balloon, I highly encourage you to use that pullback technique that was described by Ryan Madnick from UNC to just detect whether or not you might have missed a subtle focal proximal structure. Use savory dilations. My preference is to use savory dilations for EOE, particularly when I'm concerned about these long structures. And use a tactile feel. But again, sometimes a tactile feel is not as obvious as we'd like it to be. And when in doubt, check it out. If you're not sure whether you've caused disruption, just put the scope back down. I know it takes a little bit of time. Dilate two to three millimeters, put the scope down. If there's no disruption, keep going. Do more dilation. If you see a long disruption, stop the dilation session. So once you get an adequate disruption, stop that dilation session. Finally, as Dr. Early already mentioned, I like to get my biopsies after dilation. I don't think it affects the safety of the dilation. But I'm looking for that bleeding. I'm looking for that disruption to tell me that I've achieved a successful dilation. So if I don't see that, then I keep dilating. So biopsy after you've done the dilation session. There is a newer method that's been described called bougie cap. This is an optical dilator technique where you affix this bougie cap on the end of the scope. It was described for EOE patients, 50 patients from a group from Switzerland. And they described a high degree of success with this optical dilator technique. You can see that it's not a one millimeter increment, but a two millimeter increment between the bougie cap size. They did have one case where the cap got dislodged and left in the esophagus because that little tape that affixes the bougie to the tip of the scope got stuck. And they also did exclude patients with high grade structures of the esophagus. So with those important caveats, it is a technology that we may see increasingly used instead of using a typical savory dilation. The last topic here is about the safety and efficacy or effectiveness of stricture dilation. I know I'm probably running a little bit over, but I'm going to keep the second part of my talk a little bit shorter. And the safety concerns came from initial reports. These are some of the first case reports of dilation in eosinophilic esophagitis from very, you know, expert esophageal centers across the U.S. Very small series, but reported a high degree of complications of hospitalization and perforation of the esophagus from doing dilation in EOE. I think this scared a lot of gastroenterologists, shied them away from doing dilation of the esophagus, 50% in this series from Philadelphia. But we've now learned from larger series that now encompass thousands of dilations done using that conservative dilation approach. A dilation can be both effective and very safe. Clinical effectiveness over 95%. We could alleviate symptoms of dysphagia in almost every patient with eosinophilic esophagitis by doing esophageal dilation. Of course, this is uncontrolled data, but it is, I think it speaks for itself. There's a high degree of symptom efficacy for doing dilation in eosinophilic esophagitis. The caveat, of course, is that dilation does nothing to the underlying disease process. It's great at relieving temporarily the dysphagia, but it's not addressing the underlying inflammation that causes EOE or that causes these structures to develop. Perforation risks, again, initially, they were as high as 50%, but we now know the perforation risk is under 0.5% across these large case series and case reports of eosinophilic esophagitis. I'll tell you that the perforations that have been reported have all been managed conservatively. None of the perforations that have been reported have required surgical intervention. I am aware that there have been case reports not reported in the literature that have gone to surgery, but none of the reports in the literature have required surgery. They've all been managed conservatively by NPO status, getting a surgical colleague to follow along with you, and using NPO status and antibiotics. Hospitalization, about twice as common as a perforation, and these are patients that come in usually because of very severe chest pain. They end up getting admitted, getting imaging to make sure there's no perforation, but they are managed conservatively. So dilation was recommended both in the recent AGA consensus recommendation statement and also in the AGA guidelines from two years ago, that because of the high effectiveness, that dilation can be recommended for managing symptoms of dysphagia and eosinophilic esophagitis. Again, it's something that we should all feel very comfortable in doing. This one caveat is that this high degree of safety of dilation in EOE should be, the caveat is that it's being reported from centers that have really adopted this conservative dilation approach. So to summarize structure management for eosinophilic esophagitis, the assessment should include a very careful, thoughtful assessment of these potential focal esophageal inlet structures, a careful assessment of these EGJ structures. Again, I encourage you all to use a retroflex approach to assess the EGJ diameter and consider the possibility of a narrow caliber esophagus that can be very, very difficult for even expert endoscopists to detect. Bougie cap, balloon, savory dilations are all effective, but if you use balloons, I recommend the pullback. And again, dilation highly effective and safe, even for these highly severe structures that are less than 10 millimeters. With that, I'm going to transition now to my second talk.

esophageal strictures

eosinophilic esophagitis

endoscopic assessment

dilation of EOE

EOE diet

medical therapy