Dr. Peter Ngo - Third Space Endoscopy: Pediatric POEM and GPOEM for achalasia and gastroparesis

Good morning everybody. It's my pleasure to introduce someone today who interfaces with our department on a near daily basis and whose expertise is critical is a critical component to the success of our esophagealatrizia team. I love doing these introductions for people not in our department because I always learned something new about how all the things they've done, all the great things. For instance, Dr. Noenai went to the same residency program. So we both trained at UC Irvine. He attended medical school at UCLA and then did his subsequent fellowship in pediatric gastroenterology at Boston Children's Hospital. He's the current medical director of the esophageal and airway treatment center and is one of the critical providers for advanced endoscopy here at Boston Children's. Well, I think that anyone who does esophageal surgery knows about his expertise in things like endoscopic incisional therapy and the use of evax for esophageal preparation as well as his contributions and recent implementation of the esophageal occlusion balloon for temporary management of bleeding. But I didn't know this, but he's also only one of a handful of pediatric gastroenterologists in the country who offer the poem procedure, which is what he's here to discuss with us today. So please give a warm welcome to Dr. Peter Noenai. Okay, thank you for giving me the opportunity to speak today about third space endoscopy, poem, g poem, and also some of the future of third space endoscopy. There's a pleasure to talk here in front of this group and also a pleasure to talk about this topic. Let's see. All right, it does work. Okay, so we'll talk about esophageal acolygia briefly. What is third space endoscopy in poem? How did it originate? We'll spend some time talking about the actual procedure technique, and I have a number of videos, and then our adult and pediatric poem experience as well as how we manage pre and postoperatively poem patients, a little bit about the learning curve, our experience here at Boston Children's, and then sometime less on g poem, which is an evolution of that poem technique to the gastric pylorus, and also a bit about the future of third space endoscopic procedures. So acolygia results from degeneration of ganglion cells in the myantaric plexus. You got failure of lower subduals fincter relaxation, loss of peristalsis. It's a chronic idiopathic condition. It has a relatively low annual incidence. There's no gender difference. Typically, these are healthy patients that develop it, typically diagnosed between 25 and 60 years of age with a smaller percentage occurring in the pediatric age range, and there are some rare associations with genetic disorders, but most of them occur in healthy patients. One of the ways we assess acolygia symptom severity is with the Eckhart score. This is a sum of four severity scores for different clinical symptoms, and so it ranges from zero to 12. As you can see, a score under three is which is what we typically use as a cutoff criteria for successful intervention, would have some occasional symptoms in those categories. We diagnose acolygia with high-resolution esophageal monometry. You have an elevated integrated relaxation pressure. You have characteristic findings on esophageal, which most of you are familiar with, endoscopic findings that can be characteristic with a dilated esophagus, a relatively tight sphincter, and also absence of other conditions that could cause dysphagia. Endo flip, I'll talk about it in a little bit. So how do we treat acolygia? The options are pneumatic dilation, which is typically with a balloon to greater than or equal to 30 millimeters of diameter, and you really need that diameter in order to tear some of those muscle fibers of the lower esophageal sphincter and laparoscopic or thoracoscopic esophageal myotomy, and then poem. And out of favor now are things like lower esophageal sphincter Botox, calcium channel blockers because of lack of efficacy in studies. The high-resolution esophageal monometry shows three different types of acolygia. You have type one, two, and three based on a Chicago classification. All of these have a lack of relaxation of the esophageal gastric junction, which is this line at the bottom here. In all of these you have a swallow at the top. These are composite images, but you have a swallow at the top and then you have lack of relaxation with the pressure staying above 30 millimeters of mercury. And in type one, you have essentially no contractions in the body of the esophagus type two. You have panesophageal pressurization, and type three, you have a more spastic component with higher pressure, but discordinated contractions in often the lower esophagus, which has an implication for how we might treat it with myotomy as far as the length of that lower sphincter myotomy and into the body of the esophagus. So what is third space endoscopy? So conventional endoscopy occurs in the intestinal lumen, which is the first space. And over the last two decades, we've had endoscopic pioneers that have ventured out of this first space into the peritoneal cavity, which would be the second space. And that's through the lumen of the GI tract, and most particularly or most commonly the stomach, although other lumen have been used. And this gave rise to the concept of notes procedures, or natural orifice transluminal surgery. And so in 2004, Calu reported in a pig model peritoneoscopy by going through the gastric wall. And then over the next several years, 2007, 2008, you started to get these first reports of small series of human notes procedures going through the gastric wall for colisostectomy, for appendectomy. But notes procedures struggled at this point. There's a lack of optimal dissection devices and retraction devices. And really, the main issue was difficulty in having a very secure closure of the entrance to that second space. So if you're going through the gastric wall, you have to be very certain you've got that closed because you've got gastric secretions there that can leak right onto your peritoneum. And on top of that, during the procedure itself, you can have spillage of gastric contents into the peritoneum and peritoneitis risk and the like. And so really in the later 2000s, notes procedures started to fall out of favor. Didn't seem like that was going to go anywhere in large numbers and outside of major academic and investigative centers until really poem and use of the third space. So the third space is the potential space inside the wall of the GI tract. In particular, that submucosal plane under the mucosa. And this really started to get more experience in with endoscopic submucosal dissection, which I'll get to in a minute. But in Japan, in particular, they have a large number of gastric mucosal lesions and gastric cancers that need resection. In the US, we typically were using endoscopic mucosal resection EMR in which you go in with the scope with a cap, you suction up the mucosal lesion into the cap and do a snare resection of that lesion. And you can get a pretty good size chunk of mucosa and take it off in full and you protect the muscle layer underneath. But you don't have great margins necessarily for these larger lesions. And so that's what developed a little more in Japan. And I'll go through that in a minute. In 2007, Suriyama reported in a pig model use of a mucosal flap safety valve to enter that second space. So you would tunnel under the mucosa and then make your entrance into the second space. And that would prevent spillage of contents into the peritoneum and also let you close the space in a site away from that opening to decrease later risk of leakage. And then in 2007, Paserika and Texas did the first esophageal myotomy in a pig model. And then it was in 2008 in Yokohama, Japan that Harold Hiro in a way did the first poem procedure in humans. And poem has then since become the first widely adopted notes procedure. So what is the procedure itself? So the top diagram here is the diagram from Innoes first 2010 report on not only that first human poem, but his experience with the first 17 consecutive human poem patients, which all did very well. What you can see is in the top diagram, you have a diagram of what's going on. And the pictures I've put below are pictures of poem procedures that we've done here at Boston Children's. It kind of correlates with what's going on in each picture. So as you can see, the goal is to cut this lower esophageal sphincter here. Typically, it's done in the right posterior section as esophagus, but you can do it anteriorly as well. And in order to get there, you start several centimeters up. It depends on the length of the myotomy that you want to do. But you start this tunnel by creating a mucosal blab and then cutting into that blab so that you're in this sub-mucosal plane, but still inside the esophagus, that you have at the base of this area here, there's still the muscle layer. So you don't have a full thickness hole here into the medius thinum. But then you get into that space and you can tunnel over this muscle layer. And then you start your myotomy at a certain level away from the opening. And then you can do a full thickness myotomy and you close that with clips. There are other methods of closure too, endoscopic suturing and a newer X-TAC, but typically clips are used. So historically, first open myotomies, between 1985 and 1997, there were seven studies that looked at pediatric esophagus myotomies that are open with a good excellent outcome in 71 to 97% of these cases, but it's much more invasive. And so after that, there was more of a focus on all right, what's more minimally invasive when we have a study here from some of our own providers here, Fox and Fishman, that looked at 22 pediatric patients that underwent at the time minimally invasive esophagus myotomy for acolytes. And this was the largest study of the time. Most of these were trans abdominal aposcopic. And you can see the mean duration of hospitalization this is thoracolaposcopic less than three days. And this is conversion nine days and otherwise thoracoscopic 4.8 days, less than five days. So going back to poem and ESD, so I like to describe it to patients that submucosal spaces as the space where if you're getting a PPD, all the now people doing the tea spots of our newest generation won't know what I'm talking about. But the that submucosal space you can put in saline there, raise that submucosal space, but within minutes, that bleb is gone, the flu is just absorbed, but that space you can just stand up that space and work within that space quite well. So we don't have the kinds of malignancies that they have in adults and in particular in Japan where ESD took off, but as I was in this is in 2019 doing poem training, you have to learn and discuss copy of supucosal dissection techniques because it's the same technique. We did have a patient here, Boston Children's, that had a CDH1 mutation and a gastric cancer. And this is a young patient, you know, remember about maybe 10, 11 years old. And so she needed a gastrectomy, which Dr. Weldon did, but we also noted that she had a gastric inlet patch in her upper esophagus. And there have been reports of these congenital gastric inlet patches, which is gastric mucosa in your epusophagus. In CDH1 patients can, over time, convert to a gastric cancer as well. So we wanted to get rid of this mucosa as well. We considered open procedures, but sub-mucosal dissection would be much less invasive. And so that's what we performed. Here you can see this gastric inlet patch. You can see a sub-mucosal dissection where we stay above that muscle layer, but remove this tissue with clean margin there and it's attached to a wax block here. And you can see on this is initially in 2019 with narrow band imaging, you see that mucosal change easier and then a follow up one couple years later shows that that tissue there is entirely gone. So getting back to acolygia though. So in acolygia your target is this area at the lower esophageal sphincter and you need to get there through the lumen of the esophagus. But if you do your surgery and the scopically through the mucosa right there, you have a much higher risk of leak. And so that's where you enter the tunnel much higher and tunnel down first before doing the myotomy. So it's essentially the same type of surgery as would be done with a minimally invasive surgery laparoscopically, ethericoscopically. You want to dissect and cut out that muscle, separate that sphincter and you want to keep that mucosal barrier intact because that's your barrier between the lumen and all the bugs of the GI tract and your sterile space. So again, it's the same type of procedure. This diagram here is a little mislead because it makes it look like you're staying essentially within the esophagus. But really in this picture below it, you can see this is a full thickness myotomy. This is into the medius thinal space and when you get down onto the gastric cardio, you're just into the peritoneal space there. But because you have this tunnel above it, as long as you keep that mucosal intact, you should have a very low risk of leakage into that space. So some of the benefits, it's incisionless minimally invasive. You don't have to dissect out the phrenosophageal ligaments. We can't do fundo-plications right now with PoEM in pediatric snobies doing that. There is a PoEM plus F that HaroHero anyway came up with, which is an endoscopic fundo-plication. I think it has some problems that uses clips that use it's got a ways to go till it's ready for prime time, I think. But at the same time, most of these patients, especially these young patients, we weren't at least in our center doing fundo-plications at the get-go with them anyways. And our experience so far is that actually the incidence of esophageitis and it's particularly erosive esophageitis has been pretty low. So and then we all get into some of the data in a minute on that. PoEM equipment. So there are some different things we use for example for different pedals which you have to get used to for different electro-surgical pottery, currents, injection, hydro-disexion through the needle and also flushing. So a number of those pedals in addition to a number of different knives. We use saline and we stain it with methylene blue or indigo-carming. You usually want to give just the amount to make it about the color of windex and that's the stain that submucosal space so that you can see as you're dissecting the difference between the muscle layer and that submucosal space. We also use a small little endoscopic cap at the scope to move the surface of what you're dissecting away from the tip of the scope. We have some advances in endosurgical currents and as I mentioned, there's these knives that have high pressure hydro-disexion so you don't have to change instruments nearly as often. Well the setup is here we're doing them in an OR but in adult centers that do them frequently. Most of these are now done in endosurgical units like GPU equivalent. I'm not there yet so I'm keeping them in the main OR. Occasionally you can get lost in that tunnel. You can spiral in the esophagus especially with a tight LES. You have a couple of different mechanisms to try and avoid that but if you want to make sure you've gotten down onto the gastric cardio before you start doing your myotomy you can use a second tower and a second endoscope and transaluminate through there to see. You can also just inject that stained die or the stained saline come out of your tunnel and go and look and make sure you're in the right space that usually is sufficient. So some of the complications you can have you can have leak through the tunnel you can have clinically significant capnoparitanyum and capnothorax. Some degree of capnoparitanyum capnothorax is normal because you're in that space in the peritanyum and when you're in the media Steinem you can extend that air into the into the thorax without you know naturally and usually that's fairly asymptomatic and resolves quickly with using CO2. You can have bleeding within the tunnel we have a number of mechanisms to address that very very rarely now out of thousands and thousands of poems that have been people that have gotten into pericardium with an anterior poem or other large vessels but that's extremely rare and in the early reporting mucusal injuries so accidental mucusotomies were reported as complications but really they're very easily managed with clips and so there's something to make a note of just as if you were doing a heller you would make a note if you made a mucusal you breach the mucusa but you could stitch that up and to prevent a leak but it's kind of a close call so we I do think it's an important marker but it hasn't seemed to affect outcomes as far as risk of serious adverse events sometimes you can have usually with more novice and osteopist I think people can sit on the CO2 too long and blow in too much CO2 into the peritanyum and you can get some compromise with ventilation and you could need to use a needle decompression either of the chest of the peritanyum I've not had to do that but that's also no longer considered a complication of the procedure but just part of the procedure itself here we have a video of one of the poems that I've done here at children this is the first step using just an injection needle into the mucusa you inject it in pull it back a little bit to make sure you're in that submucosal space and inject some of that methylene blue and saline to make a big mucusal bleb so that's really separating out the muscle from that space and then you can take your knife and essentially just enter through that mucusa you we make a linear incision it has to be big enough to fit this cap what you see on the end of my scope which is just a little over a centimeter in diameter although newer scopes are hopefully making shrinking these things down to make them easier so you can see you undermine the edges a bit and then you can pop in with the scope cap and then here oh well it's already gone but that's something you coastal space was this gauzy material here you can see very clearly this is the circular muscle layer on the bottom and you want to try and dissect as close to that layer as possible because the overlying mucusa up here that protects the native esophageal lumen that you want to make sure you don't injure oh this one so this is within that tunnel as you're tunneling down to the lower esophageal sinker and with the different electro surgical currents this is the hydrodisexion so you can see I dissect through the tip of that knife with that stained saline and then you can use your knife with different cottery currents to kind of dissect out that gauzy submucosal space and stay right over that circular muscle layer here there as I mentioned there are some techniques for dealing with vessel this is actually fairly small vessel in the submucosal space but this is a coag-grasper which allows you to both tamponaut and clamp onto the vessel before applying a coagulation current so that you can take those vessels and decrease your risk of bleeding it is fairly important to have a pretty clean working space because bleeding in there kind of stains everything red makes it much harder than if you didn't have the issue at all so we're pretty pretty diligent with that here this is the actual myotomy so once you've dissected down you want to do that myotomy this is the circular muscle fibers and here you can see the longitudinal fibers underneath that layer and this is something called an espionife it's kind of like scissors that can coagulate and cut as well but you can see as you cut that muscle fiber it splits apart and you can see the longitudinal muscle layer underneath that quite clearly that longitudinal layer is really quite thin as I'm sure you're used to seeing surgically and so that often just separates and becomes full thickness just from just from blunt dissection so but here you can see at the lower savage finck sphincter myself and most of my colleagues would do a full sickness myotomy because you want to get more separation of the edges of the muscle as well to open up that lower sphincter and so this is really in the media's final space and when you're down at the end of the tunnel in the peritoneal space that muscle layer is pretty vascular and so sometimes as you're doing that dissection you can have some bleeding from some vessels there we often will use just saline irrigation to be able to see the location inside of that and then you can switch instruments to something like the coaggrasper to kind of grab down at the vessel area clamp it and hopefully cauterize and we can also use a low dose epinephrine to try and clamp some of these vessels and decrease bleeding for better visualization as well some people would use that in their saline mixture but most of us don't and then at the end you have your mucusotomy and that you close in like zipper technique with clips typically starting from the distal end to the proximal end and as I've learned from experience here you definitely need to make sure that this top layer that you evert the edges and you also create a ridge so that any saliva coming down really goes down either side to decrease the chance it gets into the tunnel here you have a pre myotomy lower esophageal sphincter endoscopically you can see a very dilated lower esophagus you also can see mucusal changes consistent with with stasis of fluid and esophagus it's it's really a very tight LES and when you're going through there you also want to be sure that you're not injuring the mucusa because this is the mucus that you have to keep intact to prevent leakage after your poem so one of the other things that we do is we do an endopflip measurement or functional lumen impedance planimetry and so endopflip is a balloon a low pressure balloon that we use that inflates in the esophagus or in any GI lumen and what it gives you is at the different markers on the balloon the you get the balloon pressure as well as the diameter at those markers and so using diameter and pressure you can calculate a distance ability of a sphincter and so the this is a pre myotomy this is in the esophagus you can see based on the shape of this balloon that this is your lower esophageal sphincter and the distance ability is 2.3 which is clearly abnormal and consistent with acoolagia and then we do our myotomy and then put that same catheter down and measure the distance ability again and we want to see that typically over 5 that's what's been reported to correlate with better long-term outcomes post poem and you can see it's 7.7 here and with there have been a number of cases which we're looking at more critically to show that when you have a suboptimal initial post myotomy endopflip you can do additional myotomy or additional lateral lateral myotomy or more full thickness myotomy to improve those measurements and then this is that same patient after the myotomy the tunnel is closed and I'm coming down to look to make sure there's no breach in the mucosa over that area and the LES is much more open so how do we manage these patients postoperatively and well preoperatively we make them NPO if they have a history of large amounts of stomach contents maybe longer we limit solid foods and then postoperatively NPO for the first day a esophagram on postop day 1 primarily not to look at emptying as much because you can self swelling more to look at is there a leak from the tunnel or through an accidental mucosotomy and as long as that looks okay go to clear liquids for two days soft full liquids for three days and soft solids for two days so within a week you're back on a regular diet and most of us use some antibiotic course as well some of this isn't standardized so I see a lot of variation in how long people take to advance back up to solid foods and then long term we monitor for reflexes of a gynes and try and quantify that with pH impedance as well so from some of the earlier studies this is 2014 poem that looked at follow up on 100 patients with a more long term follow up this was at least five years of follow-up so this is actually earlier poem cases but like 2019-20 when the study came out I think or 2021 and so Eckhart Square of less than three follow up of 75 months long term overall success 79 percent five year freedom from intervention 96 percent which is really quite high and significantly better than our initial pediatric poem experience which has been reported which I'll get to in a minute and 93 percent expressed complete satisfaction with the poem so and so out of this one seven out of those hundred patients had additional interventions pneumatic dilation lap heller redo poem at 51 months so there's some meta-analyses looking at comparisons between poem versus heller myotomy poem versus pneumatic dilation and one year success and really what you can see is so going to pneumatic dilation poem is favored and from a reflex perspective pneumatic dilation was favored but that's mainly because you didn't do an effect of myotomy compared to heller you have poem favoring poem on this side favoring heller on that side lap heller and and then here this is pneumatic dilation versus heller obviously heller also has a benefit but in conclusion poem and lap heller have fairly comparable efficacy and they may increase treatment success compared to pneumatic dilation and poem may have a lower rate of serious adverse events in this in this meta-analysis so looking more specifically at pediatric data with poem so this first multi-center report in 2019 looks at a large number relatively large number pediatric poem patients but most of these are performed by adult poem providers who had done a handful of kids and pooled together all of their experience both in the U.S. and abroad and it includes a number like Moan Kassab and I think Vistav Rosan here a number of different providers and so these are 14-year-old patients Eckhart pre-score was 7.5 pre-treatment data a number of different things myotomy most of them were it was a mix between anterior and posterior and the extent of the myotomy so you can also see a mix between full thickness and selective and overall there were good outcomes 91 percent of patients with an Eckhart score of less than three good technical success low adverse event rates and moderate post poem reflexes opajitis in 21 percent with 20 percent 22 percent still on PPI's let's see how much time 7.30 so got time perfectly all right so more specifically since that time we've had more data in pediatric poem and many of these are outside of the U.S. there's large centers in Asia that are doing quite a few poems and but in the U.S. there only two in here aside from my unpublished data which is down at the bottom here is wood and patrocyan so wood is James Wall at Stanford as a pediatric surgeon and he prior to doing is pediatric surgical fellowship had done advanced endoscopy in France and so had some endoscopic experience and the other one is Tim Cain at DC Children's so they reported first this is in 2020 22 21 and 37 patients but the results although technically successful there were quite a few rein interventions in this group with so far several years of follow up so out of these 21 patients 13 required pneumatic dilation in the time period one laparoscopic heller and two had a repeat poem and in the 37 from DC Children's four of them were converted to lap heller at the time of poem of course I guess if you're a surgeon doing the poem you know like eh this is really tough I'm just gonna switch so you know maybe not not so worrisome if I had to it be maybe a little more worrisome and pneumatic dilation the repeat poem so 16% required rein intervention which is significantly more than the larger adult studies and I'll get to my data here in a bit but poem versus heller you can see at cart scores for both of these drop significantly some differences and operative time is less and myotomy length is typically longer and length of stay was shorter so here is a comparison between heller and a scopic dilation and poem with a relatively large number of patients from pooled from other studies and you can see that the success rate with the poem was really quite high using the measures of success in the studies and further surgical intervention which is another way to measure success really low in the poem group although that wasn't the experience so far published in the pediatric data that we just looked at what about the learning curve for poem so that's been looked at a couple different ways this is a study from Lee Swanson from in Portland and they looked at they have a fellowship training program so they had an attending doing the original poems and then transition attending and fellow and then the fellow primary and what they measured because all of the outcomes were good they didn't have serious adverse events they were just measuring those close calls that I was talking about the accidental mucusotomy so you're tunneling you you have a little hole in the mucusa you want to make sure you close that and so you know it's definitely a goal to not have that so using that as a measure kind of give some degree of the learning curve as well potentially but what they showed is that in their their length for procedure plateaued around 20 poem cases and their accidental mucusotomy rate was eight in the first eight cases six in the next eight cases five in the next 24 cases so this is you know sometimes as many as four three accidental mucusotomy's in the same case this is data from Stavros Stavropoulos who's the largest US volume poem provider he's now done close to a thousand poems and when I worked with him in like 2015 16ish he had already done like four five hundred at the time this is an analysis of his first 93 consecutive poems and what he looked at was further improvement in procedural time so how quickly are you doing the procedure which I don't know that that's a great measure of of a learning curve but it is one measure at least and interestingly he noticed that after 60 cases there was no further improvement in how fast you were doing the procedure but the outcomes weren't really any different from the first ones versus the later ones and his accidental mucusotomy rate remained pretty constant at like a 26 percent accidental mucusotomy so what do we have so far with that Boston children's here with the poems that we're doing so we've done starting in 2021 we've done 17 cases here 15 of these are type two a callagia two type three a callagias most of these patients all but one were under 19 years of age tunnel orientation most of these posterior in one case I'm posterior is my preferred spot there's less things to potentially hit on the right posterior wall of the esophagus but in one of these cases the esophagus curves to the left a little bit near the LES and I could see that the descending order was pulsing right behind that posterior esophagus I'd decided to do an anterior poem for that case so looking at procedure length in the data that we have so far this is the procedure time for the poems that I've done in red for my first 17 poems or so it may look like it's kind of following similar curve we'll see when I get the 60 you know where I am time wise but that's not really my goal to be super fast and so far no aborted or incomplete procedures or conversion to hell or so far what about Eckhart scores so and and some additional data so length of hospitalization almost all of these patients stayed just for post-op day one their esophagem advanced to clear liquids and go there was one patient that stayed for four days because I had to re feed an endoscopy to re-close the tunnel and I'll get to that in a minute now that was actually the first poem that I did here so but so far with two to 28 months to follow only the patients this is Eckhart scores that we've got from ranging from four to 12 pre-op to post-op all under two this four is actually the 29-year-old with I think a down syndrome patient who was the issue was not so much symptoms the issue was he was coming in with recurrent aspiration pneumonia and identified to have this huge dilated nearly sigmoid esophagus so more advanced stage acoolagia and we wanted to intervene on that before it became a bigger problem so symptom-wise less and re-intervention one of those 17 which I'll get to but then you know and proof is in the putting so to speak this is a poem patient that diagnosed with acoolagia here you can see the drop and weight that's the day that the poem and recovery afterwards shows you know pretty rapid rise and weight gain afterwards and then looking at my own data on accidental mucosautomies so far we had just two accidental mucosautomies so in comparison to the adult literature I'm quite pleased with that no significant capnothorex or capnoparitinium that's needed decompression and then one tunneling so this was the first poem procedure done here and with the these brigham women's proctor as well I was not entirely pleased with the closure and we debated uh you know taking off all the clips and doing it again which I should have uh but did not and uh and uh so I'll get to that here so this is the prepomemoseophogram uh oh so this is a radiologic lesson so this is a typical prepomemoseophogram and then the post-pomemoseophogram you can see the clips here quite a ways away about probably 10 centimeters in this case up from maybe seven to 10 centimeters up from the LES and really what you want to check on this first post-up they want a soft program is is anything leaking out here or if there were accidental mucosautomies which you would know in advance are you seeing anything leak out through those areas and most of these post-pomemoseophograms have looked like this however this poem a soft program you can see the clips are in this area right here and you can see there's definitely some kind of tracked outside the esophagus there and it goes all the way down to where that myotomy is which is concerning and so that's why we went in right post-op day one took off these clips and re-closed and made sure that we really everted those edges uh so that that didn't happen again and his esophagram the following day was fine um yeah this is post-op day three uh esophagram so but we've also learned some additional radiologic lessons so here is in a post-pomemoseophogram and on first look and and I was debating with the radiologist here as well thought was this looks like it's a potential poem post our tunnel leak into the tunnel track you have your clips here you see what looks like another tracked outside the lumen of the esophagus however if you would watch this in real time everything that entered this space here would drain out and clear out into the esophagus I said that can't be a tunnel leak it's the also the base of the clips is at the very back of this area whereas if it was a tunnel leak it would be going up beyond that but to be sure we got a CT scan and like I thought you can see that there's a ridge that you create in the esophagus this is a metal clip there from closing that mucus otomy and that ridge is what uh you're seeing show up as giving you that that appearance so you can see it here and it makes much more sense you have this ridge that you pull up of mucus and so your contrast goes on either side and you can get this appearance so what about poem training so I just listed some of the things I did in order to kind of get poem off the ground here but we really don't have we have dedicated advanced endoscopy training programs now in pediatrics but most of them are focused on like ERCP as an advanced endoscopy technique which is needed more more widespread and more places we don't really have standardized training criteria for these fellowships necessarily and because of the technical complexity of doing poem you really better off being already a skilled advanced endoscopus before doing the sub neocoral dissection but then that adds the difficulty in getting people who are already practicing attending gastronrologists who want to go back into and to training practices so currently in the u.s. we have four dedicated pediatric poem providers there's James Wallace, Dan Ferd, pediatric surgeon and Tim Cain at DC Children's and then Muhammad Khan is one of my colleagues at nationwide Children's in Flumba, so Hiho and he had wanted to do poem and other advanced training advanced endoscopy but took the road of after being attending going to fellowship and fellowship before starting it but we're really looking at how do we kind of what's the plan for training future pediatric gastronrologists to do these advanced procedures. So a little bit about G poem now which is a natural extension of that third space endoscopy to the Pylorus. So G poem or also known as peroral pylora myotomy or pop most people prefer G poem because now there's the whole alphabet of poems, E poem, G poem, D poem, Z poem which we'll get to in a bit. So you can have gastroprices is more multifactorial as far as the cause of the symptoms you have sphincter dysfunction but you can have motility issues and sensory input and overlay with functional issues as well so it's not as clear cut as a Galasia which is a very natural first step for third space endoscopy but there are some ways that we can quantify things with gastroprices. A four-hour gastric emptying scan is one way but the symptoms actually don't correlate very well with gastrop emptying scans but at least is one measure to look at studies and then what we use more oftenly now is a gastroprisis cardinal symptom index and then people have also looked at quality of life scores. So what is the G poem technique? So again this is a diagram from from a journal article which I like these ones and then pictures of the G poem kind of correlating images from G poem that I've performed here at Boston Children's. You can see the first step very similar to poem you do a mucosal blab and then you make your incision into that mucosal blab you can see that gauzy submucosal spacer and you want to make sure it's not full thickness here and then you get your scope with your cap into that space you tunnel over the muscle and you tunnel to the pylorus and then you do your myotomy. This is not fully completed but most of this myotomy when you cut the muscle you get that charred appearance of the muscle and this is the ring that you're seeing the circumferential ring of the pylorus and above is the lumen of the stomach and right in the front there is the duodenal lumen of the duodenal bulb and the duodenal mucosa is quite thin so there are some additional challenges with g poem which is why one of the reasons I waited a couple of years before wanting to do g poem because if you make a hole in the duodenal mucosa is directly on the opposite side of the pylorus and much harder to effectively get a clip to close it so we want to be very careful with that isection and really start your myotomy very carefully pulling back in this area and then you just close it the opening of the tunnel with clips this is just one of the last clips being deployed here this is just a short kind of composite video of a g poem here and so you've injected that submucosal space you make your mucosotomy you get your cap into that space and then you start your submucosal dissection keeping the muscle fibers at the bottom of the screen and the mucosa protected at the top and there are much larger vessels in the in the gastric space than the esophagus and so you can see here pretty relatively large vessel probably could be taken with the regular knife but much better to use coag-graspur for vessels of this size just to decrease the risk of bleeding bagulate first and then you can take that with your knife pretty easily and then this is a picture of the pylorus after doing that myotomy you can see at the six o'clock that's where the myotomy was performed so the muscles disrupted there and as you come back here's the opening of your tunnel about five six centimeters back and you can see as you go in through the tunnel there you can see the myotomy and the duodenomy of cosa and gastric mucosa above it and this is post-op contrast study so it's same to as poem originally patients were staying a little bit longer but now most people are doing these just one day hospitals stay and some of the adult providers are selectively for their healthy patients even doing outpatient poems I'm not really a fan I think people like to have one night in the hospital make sure everything goes well I would sleep better too but here you can see a soft-of-gram post-op day one you see the clips down in the antrim right here are the clips you can see nothing leaks out beyond the level of those clips it brings up that little mucosal ridge as well and then here's your pyloric area with nothing leaking out in that area so as I mentioned you but gastroparesis you have to have a little more selectivity in your patients in a chalasia a chalasia you obviously need to do an intervention gastroparesis not always so clear but we look at this gastroparesis cardinal symptom index and it uses nine symptoms a two-week recall on a one to five-lichard scale and it looks at four items for post-prandial fullness and early society three for nausea vomiting two for bloating and most notably there is no abdominal pain in that in that score because abdominal pain is much more multifactorial and has a bigger overlap with functional as well now nausea you would think is has a pretty big overlap with functional non gastric motility related issues but nausea and vomiting this criteria actually is the best predictor of success with the poem less with the g-pom less so with bloating and fullness so we have quite a bit of data now in g-pom in adults almost none published in pediatric besides case report but this is an analysis of 291 g-pom patients in 13 different studies you can see 73 to 100 percent improvement in either symptoms or quality of life based on the measures of the study but I like this study it just is a demonstrative of the effect of g-pom it's a randomized sham controlled trial multi-center in Europe from 2022 and their DSMB stopped the enrollment after 41 out of the planned 86 patients because in the 21 g-pom in 20 sham they saw they used the decrease in gsi by at least 50 percent at six months which I like that measure and that's what most people are using now and g-pom success in this group was 71 percent in the treatment group in the sham group 22 percent but the fact that you can even do a sham g-pom is great it means that like these people who had the sham g-pom they're sitting there in the hospital afterwards they feel nothing and and they're still having their placebo response as you'd expect from their sham g-pom as an improvement in their gcs i but nowhere near the three month and six months effect that you see in the actual g-pom group and at a crossover later nine of these sham patients went to g-pom and you can see that very similarly they had improvement of at least 50 percent in their gcs i at three and six months so it definitely is showing efficacy so what are some of the current and future directions of third space and dosca be oh great I have 10 minutes for questions so I'm going to be very short here because we're not going into all of this but there's e-pom which is the regular poem for acolytic cardioresucleasia stirs subucosal tunneling endoscopic resection for eucosal tumors so just tumors if they're especially under two centimeters g-pom or pop and then zankers was the next one where they would do a septum division with the v-pom but really that's been now kind of all different kinds of diverticulae can be treated in the same way and they're more just calling it d-pom a soffadil stricter the chemical poetry for per oral endoscopic tunneling for restoration of the esophagus I think that I think it only made it on the list because it sounds like a poem but the newest on the block is for her sprung disease per rectal endoscopic myotomy and so far there are nine adult sinus series with short segment her sprung is recognized in adulthood with improvement after prem and then one eight-year-old done in in india with prem as well with reported good outcome at I think it was 48 weeks post so originally was starting to do this we wanted to just get the word out just first just get poem patience from our local referral area but then our media department has put together some things to get the word out there and after this you know the volume has started to pick up we did four poem in 2021 five in 2022 eight so far in 2023 and I have like three next month as well so in conclusion so poems first widely accepted and and practice notes procedure and it's made successful by these of the sub-mucosal tunnel it's safe and effective option with growing experience here at children's it is rapidly growing but remains limited to providers with advanced endoscopic experience and g-pom seems to be safe and effective with early pediatric experience and there are multiple new third space endoscopy procedures both in early practice and potentially on the horizon and I did not discuss the very very early data on g-pom and infant pylori myotomy which is so far not in the US yet but a report in China of like 21 patients so far I think before that becomes something that's more considered we need to miniaturize some of these devices and the endoscopic tools that we have which are because adults are doing poem and sub and third space endoscopy they have a desire to have smaller equipment as well because why have a bigger scope to do a sub-mucosal tunnel when you can do it with a smaller one and so the scope manufacturers are kind of moving in that direction which will definitely benefit benefit pediatrics so thanks to this is Stavros who did most of my training experience hero from Brigham who was a proctor that came to observe our poems here and Sam who assists with all of the endoflips and patient selection as well thank you well Peter I want to thank you for bringing us up to date on this really spectacular experience when you first approached me a few years ago and say you're going to get into this you'd probably call it a little I have skepticism on my part having done a lot of work scuff and sacramanemies and we were really were the place that introduced minima invasive isocomitaminer 4-equalasia in pediatric long time ago but you've clearly proven that this can be done in children and can be done stafely with 17 cases without significant complication and that's something that surgeons need to accept I believe and I think that you should be congratulated for pushing this forward and demonstrating to us what makes sense a lot of us when notes first came out and people make it holes in stomachs and holes in the genus to put scopes in to avoid putting them through a belly button where a scar on a belly button and such a bad thing it all seemed a little bit nuts to us and sometimes seem like an excuse for somebody who wasn't surgically trained to do surgery but this is different right and so as somebody who did a lot of staf chromatomy so I want to just publicly acknowledge that this makes sense I do have one question and we have some questions coming online for those online please enter into the Q&A you mentioned getting into the peritoneal cavity is normal when we do these minimally invasively obviously if you do it through the laparoscopic approach which is what most adult and even most pediatric places do we did them thoracoscopically for a long time for subtle reasons but it was actually rare if ever I don't recall ever getting into the peritoneal cavity because when you would down below the cruse and you get down all the way through this vincter you're actually pushing from above you're pushing down the pharynx-outgill membrane which essentially becomes the cirrhosis you don't actually have the stomachs you don't have to get into the peritoneal cavity I would think it would be even less likely from the interal lumenal approach to get into the peritoneal cavity but you find you usually do get into the peritoneal cavity or do you do on purpose? so the experience has been that the original myotomies that were done tried to be all selective circular limited just to the LES very short like three centimeter myotomies and what we found was that symptom improvement and re-operation were much higher than if you did more extensive and so if you go onto the gastric cardio one to three centimeters was the historically what people would say that's how far you tunnel but then that means you can make sure you're over the hump of that lower esophageal sphincter you can make sure you do the full myotomy of the lower sphincter and usually just to be a little safe you extended out another centimeter so onto the gastric cardio if you do extend it too much there is now that we have longer term follow-up and adults there is a complication of blown out myotomy where you actually have a diverticulum the mucosal diverticulum shows up in that area that it can extend through the whole LES so I think it's a little bit of a pendulum I think we we we were doing three centimeters and then now they've pulled back to okay you just got to make sure you're totally past the LES and onto the gastric cardio to make sure that that LES is open and the same with the tunnel people used to do like five centimeters of of potential space tunnel before you did your myotomy and now people are just doing one or two centimeters only so everything's become a little more refined in that approach I do think for things like type three acoolagia you definitely want to look at the high resolution monometry and see how large of an area is spastic to know how much of a myotomy to do but yeah so we and when I say enter the peritoneal space the gas from your insufflation enters the peritoneal space normally my scope is not typically coming out and looking at you know at the plow it tissue and such very much unless you're doing an endo a poem plus aph which is the fund oblication where you actually go out into the peritoneal space retroflex trying grab cardio the stomach grab the esophagus and cinch them together with for for to pay type and the scopic fund oblication but again I see problems with that with the equipment things now I don't think you know we'll see if I think people can improve on it with other devices yeah like many things in surgery measurements of specific sort of have to do one centimeter three centers tend to be not very physiologic we found we were doing these lorxcapathy the best measure was the endoscapist because when we had an endoscapist as you know doing this is when you see this think your pop open go a little past that and you're done and we because it's possible to measure where is this thing to start where where's the exact ejunction especially from the outside it's more of an atomic it was the statement of the obvious when you when you were true um we do have one question which actually you already answered um if anybody's doing g-pomphrapaloxinosis currently sounds like in china i want to try and at ping-hung-ju who i went and visited uh him in saying hi when i was giving congress out there and spent a couple days watching them and and yeah he went through the stomach with the same technique and opened the gallbladder and took out a bunch of stones and closed the gallbladder and then closed the stomach and i'm like okay but why why you know but yeah you might get a little more skepticism ongoing from surgeons about that one but but um i was skeptic called of the of the acholation as well so um our minds are up and that's a little high up here this is great and thank you for for walking us through it and i feel like i understand it much better and and obviously can have more confidence in it one of the things i'm intrigued about is a notion of diverticulum and let me explain because uh you know mucosa if that's all you're leaving and there's no border then you'd expect a diverticulum and in fact when we for example a soft geomiotamines when that was done for for um a soft geoletrageum one of the concerns was was the diverticulum having said that when we do pyloric stenosis uh uh we leave just a mucosal we're not worried about a subsequent diverticulum and it doesn't sound like it's here in in a collation so is it something about where you have hypertrophic muscle that's sort of protects against i'm just trying to understand it i think you form diverticulums more over time when you have increased pressure and so usually there has to be some degree of resistance distal to wherever the diverticulum forms so if you um that's why you get a dilated esophagus in acolygia to begin with but uh that's probably the main reason we don't seem much you know bowing out of the mucosa and blown out my otamines because you do the myotomy but then that area fills in with scar tissue you just need to get enough separation of the muscle to open this fincter um but then it fills in with scar tissue behind it and i i think there's enough scar tissue that forms there that prevents that mucosa from coming becoming a diverticulum and we haven't really seen that problem with g-pom so far forming a diverticulum in in that area and like just like you don't see it with uh and discuss with laparoscopic pylarmyalty. Here amazing technique i don't worry about any competition wanting to do this from our side of the street that's for sure so you mentioned gastropresis as a um complication uh is it temporary? Do you think it's due to injury to the to the vagus nerve um and can you see the vagus nerve when you're doing the procedure? I have not seen the vagus nerve and uh hopefully i never do because i think it should be out of the area that i'm at but i don't think i may have mentioned if i said gastropresis i think i misspoke um it's more gastrosophageal reflux as a risk with poem um gastroparesis we haven't seen as a complication from from the poem procedure uh not to my knowledge. People are treating gastroparesis with g-pom. With g-pom? Treat yeah so if you have gastroparesis then treating it with the uh endoscopic pyloro myotomy or gastric poem um well over to yeah well it's go over a little bit lower time but there's a lot of interest here so great talk um you had one of the on one of the sort of the advancement slides that i thought one of the second to last or third slide you had something about hisophageal strictures being treated this way? Yes so poetry is a peroral endoscopic huddling for restoration of the esophagus really what this was? adult patients with radiation injury prior chemo complete obliteration of several centimeters of the esophagus and so they would go retrograde through a gastrostomy, funnel under the under the surface of the mucosa, get into the scar tissue and just hack away until you get a rendezvous scope to see your needle come through and and then they use the uh stent to stent that area open. Why exactly needs to be sub mucosal tunneling? I mean it's not that different from what we've done with rendezvous procedures that are a centimeter gap and we just go through endoscopically and put a needle knife straight through where we know it is endoscopically and fluoroscopically. They just I think they gave it a poetry name so it made it into the house. I guess I was just trying to sort out in my head how you would get through a inflamed space. Tough, the top and so that actually raises a good question because one of the next evolution of this which Muhammad Khan and I had talked about and we actually have I have one of these cases coming up probably in April. Patients from California with distal congenital stricter but not a really tight one that's two, three millimeters that clearly needs our standard approach of endoscopic incisional therapy and evac but one that's eight millimeters and you can get a scope across it and they're eight years old now but solid food is getting stuck and so that sub mucosal tunneling technique if you can raise that third space safely you can definitely cut that stricter that doesn't have an acronym yet so I'm thinking about what that is going to be uh but then that's also not an adult problem so it's something that you know we can be easier on the forefront of but potentially uh yeah you good open but you know things like IBD and things like that I think you that you have so much fibrosis in that third space it technically becomes a lot more of a problem prior Botox injections and pneumatic dilations initially people were reporting oh that increases the scarring it makes it harder but then really studies that have looked at it have said success rates and technical completion of the procedures is is similar it might just take longer to safely dissect through the area well we're well over time I think what we're seeing here is yet another demonstration of what focused talent and expertise and collaboration between surgeons and advance and doscopists of which we have a cadre some in the room here really can make a difference for approaching kids as a team and I think our institution shines in this regard and we're incredibly appreciative of of viewing your colleagues expertise and finding new uses all the time so I'm running out and I uh turfed patient in your direction yesterday who who needs immediate spinal biopsy that you know us in the cardiac surgeons don't think there's any way of getting to and the pulmonary alters couldn't get to it either and I said I think I know some guys might feel like get there in a different way so hopefully you guys begin that that call the next day thanks so much for your extraordinary talent and beautiful presentation thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you so I don't have to stop here but I'm going to put it in the bigger area