So, I'm going to go ahead and get started with the first lecture and introduce Michael Vasey, and Michael is professor of medicine at Vanderbilt University, and Michael's going to be talking about HRM flip, pH monitoring, how and when to use it. So, Michael, welcome. Great. Thank you so much. Thank you for the panel and ASG for the invitation. How do I follow that, right? So, I have the worst scenario. Such amazing videos. I was just in awe of listening to that. So, I'm just going to go through this pretty rapidly as my task was to really just give you the top line, how and when to do some of the tests that are listed. These are my disclosures and conflicts. So, esophageal function testing is really going to depend on what it is that you're trying to test for. So, is it because of the barrier for reflux, and there is a reason that you suspect reflux disease for which you're going to use some of the tests that I'm going to talk about? Or is it because the patient has symptoms due to abnormal transfer of food, and those are usually dysphagia and chest pain? So, let's talk about barrier for reflux and some of the tests and what the indications are. Dysfunction, the barrier dysfunction can lead to a variety of symptoms, and this is the Montreal classification about esophageal syndrome and extraesophageal syndrome. So, we're going to have patients that either have heartburn, regurgitation, or you're going to have some of the extraesophageal patients such as cough and laryngitis. And the tests that you do are similar in both, but it depends on a variety of conditions, response to prior therapy or not, endoscopic findings, but that's commonly what we test for. So, the current recommendations are empiric therapy. By the time we do diagnostic tests, patients have already tried empiric therapy, and they have obviously failed. And that empiric therapy starts with PPIs once a day, and then tapering to H2 receptor antagonist or off and lifestyle modification. In many of our patients, they have to stay on PPI therapy because reflux is a chronic disease. So, when it comes to reflux testing, this is the timeline of reflux testing. We started out with ambulatory testing in the 70s and early 80s, and then wireless testing and impedance, and now with mucosal integrity testing. That's the newest kid on the block. So, here are the tests, the catheter systems. This is the tracing, the pH monitoring, where you could correlate symptoms and reflux event, the capsule, which is the wireless device, and impedance testing, as shown here. This is the recently FDA-approved mucosal integrity testing, where you can assess the contact of the sensors on the esophagus to tell us whether or not there is damage to the esophagus, possibly from reflux, and this is done during endoscopy to tell you whether or not patients potentially have reflux. That negates the need for potentially doing any wireless testing or impedance monitoring. The indications for these tests would be the same, in that, commonly, if you treat patients and they're doing well, you usually do not need to do any diagnostic testing unless you're looking for Barrett's esophagus, where you would do endoscopy. Usually it's in patients with incomplete or lack of response to therapy, or prior to consideration of antireflux intervention, whether that be surgical or endoscopic. Now, what about transfer of food? So, that's the other function of the esophagus, and usually patients that have abnormal transfer are going to present to us with dysphagia. Ignoring the oropharyngeal component, because that's a different mechanism, if you look at esophageal function, usually what we rely on are endoscopy, manometry, and dermium swallow. With endoscopy, obviously, what we're looking for is either Barrett's or esophagitis, or strictures from reflux, or eosinophilic esophagitis, as Dr. Katzke will be talking about, and sometimes we do the endoscopy and everything looks normal, although the patient has dysphagia. Now that's when we reach out for barium swallow, looking at the peristalsis and clearance of barium, as shown in this slide. So, these are complementary tests. I would recommend all the tests, depending on the situation, but not a single test is going to be classic unless you find that classic diagnosis, and in some patients you don't, so you reach out for a multitude of tests in order to give you the balanced view. So barium swallow, obviously, is going to give you different diagnoses. You could have echolasia, you could have spasm, Schatzky's ring, and Zenker's diverticulum, as the case that's being presented, and you have the bar that's shown here, and a web, proximal esophageal web. So high-resolution manometry, this is the low-resolution manometry shown here, and this is the high-resolution manometry, but the intent is to really tell us what the peristalsis is in the esophagus, and can we explain patient's dysphagia. These are the diagnoses using low-resolution manometry, so you don't do that anymore, but we use high-resolution manometry. On top we have echolasia, type 1, type 2, type 3, and then normal peristalsis. This is absent contraction, and then you have the jackhammer esophagus shown here. The intent of high-resolution manometry, again, is to identify why the patient has dysphagia and or chest pain. And then we have endoflip, which really has gotten a lot of news, especially in patients with echolasia, as far as tailored approach. I really like this about tailored approach for myotomy. I don't personally use this, but the data are pretty strong in that area. I'd like to see more data there, but I'm looking forward to those about how to best treat patients with echolasia with a tailored approach, especially with POM and how much of a cut one would have. So when we think about then esophageal dysphagia, the tests that we're interested in, either mechanical, peptic stricture, malignancy, Schottky's ring, you're going to depend on endoscopy, mostly some barium swallow. And then if you're looking for motor dysfunction in the esophagus, such as spasm, echolasia, or absent contractility, that's when you would depend on endoscopy, but more importantly, high-resolution manometry to give you the diagnosis with the subsequent therapy. So going back to our esophageal testing, these tests up here, pH monitoring, is going to tell us about the barrier dysfunction and suspected reflux. And the test below, essentially, is going to tell us about the motility pattern and what to do for our patients. All right. I'm done. Three minutes early. Thank you so much. Appreciate it. Thank you.

HRM flip

pH monitoring

esophageal function testing

reflux testing

transfer of food