All right. We'll go on to our next case-based discussion session. We'll have Dr. Gowali come up and present a case on common pitfalls in HRM. Thank you to the moderators. I hope you guys are enjoying yourselves. Mine is not necessarily going to be a case. It's just going to be show and tell, and we'll stop whenever you guys want with whatever questions you guys might have. It's going to be mostly manometry and pH-based, and we'll talk about little tips and tricks and things that you guys might need to know. Disclosures again. So one of the things that we'd like to see in a high-resolution manometry is where the esophagogastric junction is. And one of the best ways to do that is to ask the patient to take a deep breath. When you breathe in, the diaphragmatic crura contract. They squeeze against the catheter, and you can see that compression. The other point that you see with breathing is a negative intra-thoracic pressure and a positive intra-abdominal pressure, and that completely reverses when we breathe out. So the expiration phase, the intra-esophageal pressure is going to be higher than the inspiratory phase, and the intra-abdominal pressure is going to be lower than the intra-abdominal pressure during the inspiratory phase. It's important to look at those patterns, especially when the EGJ is hypotensive, when the EGJ is very weak. It's important to do that. And one of the important things that we try to teach our operators is to recognize this, because this is what we want them to avoid. By the time we read the studies, the patients are done and gone. And so the operator needs to recognize this. Everybody knows what this is, right? This is a curled catheter. You can see that the catheter has curled at this point, right there. And so you have a mirror image pattern, okay? This is a mirror image pattern. So that's contraction, and that's where it is curled, okay? What's happened here? Can anyone point out what's happened here? Any ideas, anyone? Okay. Is this a critically imperfect study? Not necessarily, okay? Whenever you see this pattern, it means that the catheter has very likely gone through the lower esophageal sphincter, okay, and may not have traversed the next obstruction, the next area through which the catheter might need to pass. In a person without previous surgery, that next area is probably going to be the diaphragm, okay? So this might be a situation where the person has a hiatus hernia. The catheter has hit the wall of the hiatus hernia and come back up into the esophagus, okay? So you don't see that inversion pattern, and you see a mirror imaging here, okay? Can you think of any other situations where this might happen? Anybody? If it pours. I'm sorry? If it pours through the... If it passes, if it perforates or we pass it through the wall, maybe? Oh, I hope we never... A gastric pouch or the proximal stomach in somebody with a sleeve, okay? This happens to be the patient with a gastric pouch, with a Roux-en-Y gastric bypass, okay? You can see this pattern. This is not necessarily a critical imperfection, okay? This is a situation where you can visualize the lower esophageal sphincter relaxation. You can see that it's relaxing. Your IRP may not be accurate, because you don't really have a good gastric baseline, and the IRP is measured above the gastric baseline, okay? So you may have to make a visual impression. You may have to realize that the true IRP may be higher than what you recorded, because if the pressure inside that pouch is elevated, then your IRP will be falsely low, okay? So that's also a curled catheter. Here's another example of a curled catheter, okay? You don't see that pressure inversion pattern. In this case, there is pressurization in the esophagus during these events that the patient is trying to avoid from swallowing. He's contracting their UES, maybe retching, and you see pressurization that goes all the way through. The catheter is curled probably somewhere in this area, okay? In this case, the lower esophageal sphincter looks like it has been traversed, but you don't see any inversion of pressure, okay? You see these bands of pressure that go straight through. I guess I can point with this. Where am I? What am I doing wrong? Okay, here we go. You can see these bands of pressure go straight through. There is no inversion at the level of this band of pressure. So that band of pressure there is the lower esophageal sphincter without diaphragm, okay? So this is a situation where the person has a large height of scleronia, and the catheter has not traversed the diaphragm, okay? And this is not a critical imperfection. You don't need to repeat this study, but if you wanted to try and get the catheter to traverse, you could stand the patient up. Sometimes the hernia straightens out when the patient stands up, okay? Any questions so far? What about here? This is another one where the catheter has traversed the lower esophageal sphincter, but it has also traversed the diaphragm. You can see diaphragmatic crural contraction here. So this is diaphragmatic crural contraction, but you see it again in a mirror image pattern. So this is somebody with a gastric pouch again, or a sleeve, where there is no hernia, right? Has traversed the esophageal gastric junction. So this actually is a problem if you're going to measure the IRP, because you'd have to place the gastric baseline here, and not here, okay? If you place the gastric baseline here, this is actually intraesophageal pressure. So you actually have to place it here, and then do a visual assessment of whether the LES is relaxing, and that's okay. You can look at the high-resolution manometry study. This is doing the resting phase, but you can look at it during a swallow. In this case, we were able to pull the catheter back, and reposition it so that it did not curl back, all right? So these are unusual patterns. Here's another one. This was a referral that was sent to me for a very unusual esophageal pattern, and actually, it's a curled catheter in somebody with probably a hypercontractile esophagus, okay? The other clue that you can get from a curled catheter is that there is some obstructive element in the esophagus, or the esophagus is tortuous, or the LES is not relaxing. So that's another element that you can get from a curled catheter. In fact, when we looked at a whole year's worth of manometry studies, we found that most of the curled catheters where the cases had to be aborted were actually patients with type 1 achalasia with a dilated esophagus, and that is actually a change of practice that if somebody wants some manometry in that setting, then we'd like to place it during endoscopy or just do a flip, just move to doing a flip in that setting. Here's another one. This is another curled catheter. It has hit the lower esophageal sphincter and turned back on itself. So this band of pressure is the LES complex, but it has not traversed it. It just came right back up, okay? Here's another one, curled catheter again. Sometimes these are subtle. It's difficult to, it's easy to overlook, and this was actually missed by our operator. Our operators are pretty good, but this was missed because they took one of those lower bands as being the lower esophageal sphincter, and it isn't. You don't see any inversion, and you see mirror imaging. And when you turn the impedance on, you can see the mirroring of the impedance bolus retention in the proximal esophagus. This is yet another curled catheter, okay? Again, you see the bands going up and down. Important to look at it very carefully, and one of the clues to sorting this out is to click on this little element here that says set range and change your baseline at the bottom. That'll change the colors, and you'll see subtle pressurizations or subtle pressure impressions when the pressures are very low, and sometimes that'll bring out a very high potential LES or a diaphragmatic hiatus that is wide open that is not exerting a whole lot of pressure, but if you change the pressure metrics, you might be able to see it. This is also a curled catheter. That band in the middle is because of tortuosity of the esophagus, the catheter touching one of the torrents in the esophagus, the tortuous areas where the mucosa, the wall actually juts out, okay? Another curl, you can see I have a little collection of these curled catheters. This is another curled catheter. Now we're going to move on and talk about these separations, these hiatus hernia separation between the lower esophageal sphincter and the diaphragmatic curl impression. In this case, you can see that the diaphragm is separate from where the lower esophageal sphincter is, and this separation in this case is about 3 centimeters, okay? If you are measuring the IRP here and the IRP across the entire complex is elevated, it does not necessarily mean that there is a problem with the lower esophageal sphincter. In that case, the thing to do is to move the IRP box to include just the lower esophageal sphincter, so to include just the lower esophageal sphincter so that you get a true IRP of the LES, and then move the box down to across the diaphragm and see if the diaphragm is obstructing. In this case, it does not look to be obstructing because there is enough spacing between those curl contractions and the pressure seems to be letting up that it looks okay, right? But I will show you an example of, I don't know why, I don't know what I'm doing wrong here, that's the hernia, it's a non-obstructing hernia, but look at this one, okay? You see pressurization within the hernia, okay? You see pressurization within the hernia. Whenever you see pressurization, that means that there is nowhere for that pressure to go because there is an obstruction at the distal extent or the proximal extent. In the normal setting, when there is no obstruction, that pressure in the esophagus created by contractions or breathing or whatever dissipates into the stomach. The stomach is a bigger organ, it can absorb that pressurization, you don't see it. That's the reason why you don't see intrabolus pressure in the absence of obstruction. So whenever you see pressurization of this kind here, this is the lower esophageal sphincter diaphragm, you see pressurization. This is an obstructing hernia, okay? So that's a four centimeter hernia, that's an obstructing hernia, type 3 EGJ. This patient has dysphagia or chest pain, it's probably from this. This person says they feel food sitting in the epigastric area after they eat and then when they straighten up it falls into this, that's the usual history, falls into the stomach and the dysphagia goes away. That's an obstructing hernia that probably should be repaired. Oops. Sorry, Prakash, if we can do another two minutes, we just fell behind in our schedule. Okay, okay. Thank you. Sorry about that. We'll go quickly. It's not your fault, it's our first session's. Another obstructing hernia, okay? You can see another obstructing hernia. This is an obstructing hernia and the catheter has not traversed the diaphragm. And a lot of times these kinds of hernias have both a parasopagal and axial pattern. So I'm going to go through this rather quickly, you probably know the classification of the EGJ, type 1, no hernia, type 2, small hernia, so less than three centimeters, type 3, three centimeters or larger. And if it is not clear if the EGJ is traversed, then it's worth looking at a swallow. And sometimes that will tell you whether the EGJ is traversed or not. So if there is trouble traversing the EGJ, there are certain maneuvers you can use. The patient can stand up, raise their arms, you can put a twist, you can have the patient gulp water. If there is trouble traversing the diaphragm, usually you don't need to do much, okay? If a sensor is malfunctioning, you can turn it off. And you can do that using the tools and that will create a more smooth contour. Now you can sometimes get these vascular markings from the heart or from the aortic arch, and you can usually solve that by tilting the patient slightly to the left, the vascular structure will fall away from the catheter. We don't accept dry swallows. We don't like to accept swallows next to any other esophageal event, like a TLSR or a belch, and we don't like double swallows. So these are all rejected, and the operator should get another more appropriate swallow when we encounter these. All right, we're going to go through pH and pH impedance rather quickly. This is a wireless pH study. Should I go through these? Maybe, Prakash, we'll save it for... We're going to do this again. We could do it to the next session. Get around. That's okay? Sorry, Prakash.

HRM

high-resolution manometry

esophagogastric junction

curled catheters

esophagus tortuosity