We will next go to Northwestern University with Dr. John Pandolfino for a demonstration of high-resolution esophageal manometry. Dr. Pandolfino, we can see your screen now. So what I was asked to do today was to actually look at a manometry study that's actually flowing in front of me right now and present a few cases and just talk about, you know, how I evaluate these patients, how do we perform manometry in achalasia, and I will tell you that achalasia, you know, is a really beautiful disease state because it has such a heterogeneity, and although there are three, possibly four subtypes, if you include EDG outflow obstruction, that's not where the beauty goes away in achalasia. There are so many little nuances that I think are important for people to appreciate when they're evaluating these patients that often get overlooked and glossed over. Similarly, I think there's a very big difference between when you are actually doing a manometry to diagnose achalasia and then doing a manometry to actually follow up on achalasia. I will tell you that in my practice, I almost uniformly used high-resolution manometry to follow up patients at 6 to 12 months, but outside of research protocols now, I pretty much abandon that approach and typically utilize time-varying esophagram and functional luminal imaging probe if their time-varying esophagram is abnormal, and I'll speak to that in the lecture later on today. Now, what you're seeing here on the screen, hopefully, are swallows that are occurring in a very timed, live-sequence fashion in terms of the space-time domain, and what you're clearly seeing here is that we're getting very good swallow durations here. There's the upper sphincter contracting and relaxing, opening here. I will put in the Z so you can see the liquid here. The purple color, obviously, is the impedance signal, and really what I just want to get at here is that when you see a manometry like this, and it's important, a lot of these patients are very uncomfortable, and although we have the Chicago classification protocol, which states that we should do 10 supine swallows, we should do multiple rapid swallows, then move the patient into the upright position, do an additional five upright swallows, then potentially do multiple rapid swallows again, and then maybe some solid food challenges and then a rapid drink challenge, I think it's really important to realize that many times when you're seeing these patients, you have a pretty good pre-test probability that this is achalasia, and when you do the manometry, is it really necessary to put people through this enormous exam that sometimes can last 20, 25 minutes in order to complete it to make the diagnosis clinically? Of course, research-wise, we're always going to try to get our research protocol, but in the context of patient comfort and knowing how uncomfortable manometries are, having had nine of them now myself, I'm certainly sensitive to that issue. So this is a beautiful example of a type 2 achalasia pattern. You're seeing this pressurization here. It's quite beautiful. There's really no contractions, and in this particular example, the patient's pressures are ranging anywhere from 30 to 45, so definitely pressurizing, not really something suggestive that there's too much activity underneath there, but certainly there might even be a little bit of mild dilatation in this patient, and that's also an important thing. The distinction between type 1 and type 2 achalasia is actually very arbitrary. That 30 mmHg cutoff that we use to define this had no basis in science or biomechanics. It really was just this observation from classic physiology in the esophagus that noted that a peristaltic wave with a closure pressure of 30 mmHg was typically uniformly able to empty the esophagus, so that was kind of the threshold, the physiologic threshold for bolus transit and emptying across the esophagal gastric junction, and that's really been the reason we use that threshold, but I would tell you, if you really were clearly trying to define whether someone has dilatation without recoil and the ability to normalize, the pressure probably should be on the range of 10 mmHg. In fact, we looked at that, we presented an abstract at DDW, we never published it overtly, but certainly that probably is the issue. The other fact is that the beautiful thing you're seeing here too is that as you continue to fill the esophagus with more and more volume, you start to see a rise in the panesophageal pressurization level, so you go from green now to yellow, so now you're getting up to the point where the pressures are around 60 mmHg, and that's kind of an important component because we believe that once you get to panesophageal pressure greater than 70 mmHg, that is a risk factor for you to see spasm post-treatment when you've had successful myotomy at the esophagal gastric junction. So here we've gone through, as I've spoken here, 10 swallows, you can clearly see that the EGJ is not opening, you can clearly see that there is bolus retention that is significant, the panesophageal pressurization levels are way above 30, so this would be very consistent with a type 2 pattern. Now I would not fault someone in a busy clinical practice who just scoped a patient, saw that they had a tight EGJ, there were secretions in the esophagus, that maybe you can get away with finishing out the 10 swallows here and being very comfortable with this diagnosis with probably an accuracy level of 99% and not putting the patient through. So I would certainly not advocate for a full research protocol on all of these patients. Now that being said, we did do a full exam on this patient, and I'm just going to kind of take you through how we landmark this and what's very important. And the other thing that I think we've kind of neglected focusing on IRP is the quality of the high pressure zone. Now you can clearly see in this example here, this is a patient who has essentially a high pressure zone, and I'm going to just throw in the isobaric contour tool here for a second. A very short high pressure zone. Now you know, and this goes back to this arbitrary picking of myotomy length, and I'm not a big fan of standardized myotomy. I think that when you look at this, physiologically it makes absolutely no sense to me to do a myotomy up here and a myotomy down here. I mean, this person has a high pressure zone that is probably on the order of one to two centimeters, which if you look at most patients, the high pressure zone is about three centimeters, and we're doing these enormous myotomies that may lead to other issues later on in terms of complications one to two years later. But that being said, in this particular example, I'm just going to take you through, I'm going to put my landmarks here, and as anyone who's ever seen me do this, my landmarks are not sophisticated in terms of where I put these things, because once again, the most important thing is just to have these orange balloons outside of where you demarcate this. I think the most important thing actually is making sure that you've assessed the EGJ and have identified the pressure inversion point. Every study should have at least a few deep breaths, a couple of sniffs, so that you can document this, because sometimes it's very difficult to get the catheter into the stomach in patients with achalasia, because the esophagogastric junction is not opening, they may have abnormalities in anatomy, a sink trap, or an angulation. So that being said, we're able to identify our landmarks, you make sure the upper sphincter is located here, gastric pressure, you don't want it too close to the esophagogastric junction, and once you've gotten this reasonably localized here, and I feel pretty comfortable with these, this is the pressure inversion point tool that you can use, I rarely ever use that because it's so easy to see that there's a pressure inversion point. And then I'll just kind of scroll through, and I'll kind of get my IRP measurements. Remember, IRP is not a line in the sand, that 15 millimeter per mercury cutoff is once again, you know, a logistic regression curve fits that better, so you know, 20 millimeter per mercury is better than 15, 30, your post test probability, once you see that is going to be a lot higher. But you can see people with achalasia with an IRP of 10. And that's because once again, the EGJ can relax, but not open, and you can maybe see a decent relaxation pressure because someone started out with a pretty hypotensive EGJ, but they don't relax enough, and they don't open the esophagogastric junction, and therefore, they actually do not have emptying through the EGJ. So in interest of time, I'm not going to take you through all of this, but you can clearly see here that this patient's IRP is elevated on every single swallow, there's absent contractility and panisobdural pressurization. Now we'll talk a little bit before we go on the multiple rapid swallow, I think this is an important thing to do, I will tell you that we do not do that in the supine position, especially in achalasia patients, because I have a very sensitive kind of slant towards the patient aspirating and regurgitating during the multiple rapid swallows when they already have a column of liquid that's sitting up into their throat area. But here you can clearly see, once again, the IRP is elevated and you get this panisobdural pressurization. And then, of course, I do think the RDC is extremely important, especially if you have some degree of trepidation on your diagnosis, in that the IRP may be a little bit borderline, you're not really seeing any panisobdural pressurization, by doing a rapid drink challenge, you can actually bring out a very subtle obstruction sometimes, this is not subtle, but you can bring out a subtle obstruction, and probably the best evidence of a subtle obstruction is really not the IRP, although you can clearly see in this example, the IRP is recording 33, really what's more important is the panisobdural pressurization here, in fact, I don't even care what your IRP is here, if I see this pattern in your IRP, you know, is 4, you know, you have achalasia to have proven otherwise, and there's probably some issue with your gas replacement, or where you put your sleeve here. So, in these instances, you know, I feel like the RDC has some value. So let's take a look at another patient here. And once again, shut this off here, but here's an example of a patient we're going to go first of all check and make sure that the catheter is in place you can see the deep breaths here you can see clearly that the pressure goes down in the chest and then you can see the curl contraction and the intra-gastric pressure rise. I'm going to show you if I take the pressure inversion point tool you can clearly see that all the peaks along this red line are up and as you go through the esophagogastric junction now they're all down and hence you have a negative inter-thoracic pressure during inspiration and a positive pressure in the gastric portion so you know the catheter is placed appropriately here and certainly you would begin your study with your swallows and I'm going to just kind of play this just as it was real time and you can clearly see here that this particular patient I'm going to bring this up here so I can highlight this just a little bit you know when many people swallow they swallow a lot of air and you can just see this pooling here but here's the the impedance signature showing the swallows but you can clearly see here already there's absent contractility the esophagogastric junction is really not opening here I've got the isobaric contour tool set at 30 actually let me scroll it up here a little bit it's at 29 not a big difference between 29 and 30 but just for the intents of the presentation here you can clearly see that these swallows you know once again are cinching a diagnosis of achalasia and the question now is is this patient someone who's going to have type 1 or type 2 achalasia as I mentioned I think that distinction is not as important as understanding the anatomy if I see someone with type 1 achalasia who has a straight esophagus with some moderate dilatation you know I'm still pretty comfortable that that person's going to have a very good outcome regardless of which approach you use whether it's pneumatic dilation home or hell or my honor so here you can see as the study progresses there's very little emptying and you can clearly see that this patient starting to accumulate more liquid you can get a superficial measurement of diameter using impedance and an application of ohm's law there are some technologies that allow you to do this so I'm just going to scroll through here a little bit now as you're getting through this you can see clearly that on this particular swallow there is probably a little bit more bigger in the swallow and you see this beautiful panisopter depressurization and one of the things you see when you see this level or this change is that the upper strength is doing what it's supposed to do here you can clearly see that it is protecting this particular patient or at least trying to protect this patient from aspiration and there are two specific upper esophageal center reflexes that have been shown in physiologic studies from both the milwaukee group and our group in the past and and some of the groups in australia where there's this difference in upper esophageal center function depending on the rise and the level of the intraesophageal pressure so during a belch when the pressure rises rapid in milliseconds the upper sphincter tends to relax so that you can belch however in patients where there is retention and there's a slow fill the upper sphincter tends to do what it's supposed to do and protect you from aspiration and there are some people believe that that is part of the manifestation of the symptomatology of achalasia because it's like a water balloon being squeezed on both ends and that pressure that's being generated in the body can elicit some issue in terms of stretch receptors possibly and that's one of the issues but here you can clearly see the patient finally acquiesced at the upper sphincter and probably regurgitated a little bit here or at least belched some of the air out so now you've walked into the study that looked borderline type one and now it is quickly converted to type two here but you're getting a sense that these pressures are pretty high you know and you're seeing here that these pressures now are red you know this is pretty high and this is someone that we would typically be concerned likely has non-occluding contractions in the esophagus that are most likely spastic and premature that are generating this high pressure in the old days we used to think that this was due to longitudinal muscle shortening but as you can see here there's very little longitudinal muscle shortening to explain the Boyle's law principle that would cause this pressurization and many times when you look at the esophagram on these patients they actually have non-occluding contractions that almost look like spasm but not quite to the occluding level of a rosary bead esophagus so once again you can clearly see these pressures are very high the multiple rapid swallows here you can see afterwards the patient here emptied a little bit so you know with this this is a good example here i'm going to stop this you know you can clearly see that the patient with these multiple rapid swallow was able to generate a much lower les pressure so this patient may be a little bit earlier in the evolution of achalasia and they were able to empty the esophagus the pressure levels got down but of course after that last swallow this pressurization started to accumulate again and then the patient started to develop that panis after pressurization and you'll see that again here in the rapid during challenge so once again you'll see this this is actually just the catheter being moved out and really not longitudinal muscle shortening and excursion there is a little bit of artifact here but you can see here just another check of the intergastric pressure here so now let's look at this patient after a successful myotomy so this is someone who underwent palm had a successful myotomy doing extremely well eckert score is great and let's see what they look like now so here's the post poem and the first thing you already appreciate is the fact that you know this this intra esophageal pressure level has pretty much gone away so you can imagine here was a patient before the palm their esophagus was filling with liquid it was pressurizing to a level of 70 to 100 millimeters per mercury and and that in and of itself is going to cause dysphagia trying to ram more bolus into that esophagus is going to be extremely difficult so here you can clearly see that there was a very nice myotomy there's a very good drop in terms of their irp and and just the overall signal and but probably the most important thing here is the fact that i'm not so concerned with what the irp is here because in most of these patients i'm going to wind up doing a flip but really the most important thing here is that this patient has decompressed their esophagus and the interesting thing here is that although this person's irp is a little bit abnormal in both the supine and the upright position i'm going to go to the upright maybe a little bit better here you know went from 30 you know to the 20 you know this would still be considered abnormal with a little bit of pressurization this is a dramatic benefit let's take a quick peek at the multiple rapid swallows where you're challenging the esophagus there's a little bit of pressurization here but so much better than what you saw with that last page with the last venometry and here also a little bit of pressurization so this is someone who obviously is is doing better their esophagus has decompressed they have had a very good myotomy based on flip and and i think there's very good correlation between what we're seeing on this hrm this patient's flip and then how they're doing clinically and then also how they're doing on their their esophagram so i wanted to finish with a little bit of extra time for questions so um why don't we end here and and open up the panel well thanks john that was great um what what uh metrics do you look for most in terms of the postpone myotomy if you're looking to to to see it seems like flip is very very clear that we have distensibility and such but it seems like with with with with the doing the hrm there's always a question about does the irp matter does does baseline sphincter pressure matter um is this pressurization which we should look at what what what key things do you like to see after a poem yeah so i think that if um if you are following people afterwards typically my my standard clinical approach is esophagram esophagram is the best test to assess patients after a therapy at the esophagal gastric junction because the most important thing that you're looking at is did they decompress their esophagus so is that pressure gradient done and are they emptying are you able to empty that esophagus right so so to me what happens in my algorithm i'll cover this in the lecture later today is i typically get an esophagram if the esophagram is abnormal those are the patients that i bring in for endoscopy would flip um the the patients that i'm actually getting high resolution manometry in in the context of of assessing patients postpone with symptoms is really whether or not i'm trying to define spasm although you can pick that up on on flip too so the the the likelihood that i'm even getting manometries to pick pick that up is getting less and less so really what i'm looking for if i was going to use manometry and you don't have flip um and you've gotten an esophagram and your esophagram looks bad they have retention i'm looking for a i would it looks like you went on mute john muted me let me see if i can uh okay cool all right i think someone's getting a little annoyed with my voice but anyway um i think that if you're if you're thinking about you know that i'm looking at pan esophageal pressurization and the irp and really what you're looking at the irp it's not the number it's did they have a good effect you know did they go from 40 to 20 you know is there some change that you're seeing there but you know as we know there's a lot of artifact with irp especially when there's abnormal anatomy and someone with a sigmoid esophagus or a dilated esophagus so you have to you know you have to look at that with some degree of suspect when you're looking at it john do you do you think that we can get away from manometry entirely now do you think if they're you know you know things fit in terms of um you know you know past history symptoms the barium study the dosby the end of phleb um you do you think we still need anything from manometry so so once again i always tell everyone my conflict you know i have a ip on flip panometry i get 75 every time they sell a machine um you know most of that goes to charity and scholarship so if anyone wants that's my conflict um the bigger conflict is probably i've spent my whole life working on this technology so i'm obviously biased now i think in in someone who's comfortable using flip um i rarely need manometry anymore um but that being said you know there are people you know the learning curve is steep and i think for diagnosis of achalasia and normal motility i think flip is is excellent um you know do i think it's going to replace manometry completely no because i think that manometry still is really important belching syndromes patients with regurgitation um who you're not you know you don't you're ruled out um achalasia uh you know those kind of patients so i think i'm getting less and less um involved in in using uh manometry especially in the post-treatment patients um but you know i i think it's still going to have some use in in a lot of niche presentations thank you dr pandas you know

high-resolution esophageal manometry

achalasia

evaluation

follow-up

diagnosis

limitations