Abbreviations:ABE (Association for Bariatric Endoscopy), ASGE (American Society for Gastrointestinal Endoscopy), BWH (Brigham and Women’s Hospital), ESG (endoscopic sleeve gastroplasty), NOTES (natural orifice translumenal endoscopic surgery), POEM (peroral endoscopic myotomy), RYGB (Roux-en-Y gastric bypass), TORe (transoral outlet reduction), TRIM (Transoral gastric volume Reduction as Intervention for weight Management)
It is important to understand the past in order to innovate into the future. As a member of the inaugural editorial team at iGIE, I am excited to launch a section on historical considerations in endoscopy. Over the course of my brief career, I have had the incredible opportunity to have mentors who instilled in me the value of history as a launching pad to innovate and think outside the box. It is my hope that these historical perspectives will provide valuable insights to future generations of endoscopists while encouraging them to further the science and art of GI endoscopy via innovation and investigation.
The year 2022 marked the 10th anniversary of endoscopic sleeve gastroplasty (ESG), and 2023 will mark the 20th anniversary of the first application of endoscopic suturing to treat obesity and with it the birth of bariatric endoscopy (Fig. 1). Straddling the fields of obesity medicine and bariatric surgery, bariatric endoscopy fills an important niche in our global obesity pandemic. With a strong social media following and growing presence through the American Society for Gastrointestinal Endoscopy (ASGE) and the Association for Bariatric Endoscopy (ABE), bariatric endoscopy is increasingly being adopted worldwide in selected patients with obesity.
Christopher C. Thompson is our inaugural Editor-In-Chief and an internationally renowned brand synonymous with creativity and innovation in endoscopy. Dr Thompson has multiple patents, startup companies, and countless publications to his name and is credited with having performed the first bariatric endoscopic suturing procedure in 2003 and the first ESG in 2012. In addition to having advanced the field of endoscopy, Dr Thompson has tirelessly mentored numerous trainees both in endoscopy and in research, receiving the ASGE Distinguished Endoscopic Research Mentoring Award in 2019. It is therefore fitting that a visionary, pioneer, and mentor like himself would be our first guest in the Historical Considerations section of iGIE.
Phillip S. Ge (PSG): Dr Thompson, thank you so much for taking the time to do this interview. It is truly an honor and privilege. Why don’t you go ahead and tell us a little about your own background and training in endoscopy.
Christopher C. Thompson (CCT): I was trained in traditional therapeutic endoscopy nearly 20 years ago at the combined Brigham and Women’s Hospital (BWH) and Massachusetts General Hospital advanced endoscopy fellowship program. At the time, this entailed diagnostic EUS and ERCP. We also were performing EMR for large colorectal polyps and advanced hemostasis techniques. The unique aspect of my training that ultimately shaped my career was exposure to the EndoCinch (CR Bard, Inc, Murray Hill, NJ, USA) endoscopic suturing device, which at the time was being exclusively used to treat GERD. I realized over the course of my fellowship training that the device seemed versatile and could have other potential applications, and I ultimately used it as a launching pad to innovate some of the early bariatric endoscopic procedures.
PSG: After your training, you then stayed on at BWH. Tell us about your early experience as junior faculty.
CCT: Mentorship was of foremost importance to me, and I decided to stay at BWH because I felt that there was very strong mentorship there from Dr David Carr-Locke and others. That ultimately proved critical for what I was interested in doing because the right mentor is like a safety net. From an innovation standpoint, the right mentor gives you the encouragement and freedom to pioneer procedures and is also there to support and protect you if you get stuck or get in trouble.
As such, when I started as junior faculty, I knew I wanted to push the envelope in natural orifice translumenal endoscopic surgery (NOTES, a nascent concept at the time) and in bariatric endoscopy (which did not exist at the time), and I knew that I would need the mentorship in order to have a chance at being successful. Given how much I benefitted from my own mentors, I have since encouraged every one of our subsequent advanced fellows to seek out that same sort of mentorship in the next phase of their career.
PSG: For most of your career, you’ve been a pioneer in every regard, but what specifically inspired you into bariatric endoscopy?
CCT: The timing was right, and the opportunity was there. When I was in fellowship, the obesity pandemic was becoming more evident across the United States but was being largely ignored by gastroenterologists and endoscopists. I believed that as physicians of the GI tract, we had a unique skillset that if properly developed could have a positive impact on this struggling and underserved patient population.
At the same time, on the surgical side, it was the early days of laparoscopic Roux-en-Y gastric bypass (RYGB). There was an increasing clinical need for preoperative evaluations and postoperative care for this patient population from a GI and endoscopic perspective. We also had to deal with a lot of complications as these surgeries were being developed, including anastomotic leaks, gastrogastric fistulas, and weight regain. I worked together with surgeons to establish new workflows and streamline care for these patients. Shortly after joining faculty my first academic title was “Director of Bariatric Endoscopy,” which was completely made up at the time but now seems to have gained traction.
Finally, we also had a lot of new technology that was becoming available in part because of the advent of NOTES. Key among these new technologies was the development of an endoscopic suturing device. Together, these advancements provided the perfect nidus for innovation.
PSG: Tell me a little about the beginnings of bariatric endoscopy.
CCT: Intragastric balloons had come and gone in the 1980s, but that was just a procedure. I believe the field of bariatric endoscopy came about in the early 2000s as a result of the increasing need to endoscopically address surgical complications while at the same time there was a variety of endoscopic surgical procedures being developed to treat obesity.
A seminal moment was in 2003, and I had only been on faculty for a few months. I had a patient with a history of RYGB who was suffering from significant weight regain and GERD from a gastrogastric fistula that was just below the lower esophageal sphincter. I had been performing antireflux procedures with the Bard EndoCinch device at the time, and although it had never been described before, it naturally made sense to try closing the fistula. So I called our bariatric surgeon and said, “Hey, I think I can close this hole with this endoscopic suturing device.” They were excited by this possibility, given that at the time, surgical revisions were associated with high operative morbidity and even mortality. I closed it with the EndoCinch, we did an upper GI series that demonstrated successful closure, and they clinically improved. The surgeons were amazed by this, and I believe that was the real beginning of bariatric endoscopy because at that point we realized we could use endoscopic suturing to help patients lose weight.
The best part is that the patient’s fistula actually closed, they started losing weight, and their reflux symptoms improved. As you know from the subsequent literature, in hindsight this approach only works in a minority of patients, but this built confidence for the bariatric surgeons, and they were willing to send additional patients.
PSG: Such an amazing story. Where did you go from there?
CCT: Once we realized we could use endoscopic suturing to close fistulas and help bariatric patients lose weight again, it was a small step from there to consider making the gastrojejunal anastomosis smaller to enhance what was believed to be the restrictive mechanisms of the procedure. We did a small review from our own historical series and realized that outlet size appeared to correlate with weight regain. This concept eventually led to the development of transoral outlet reduction (TORe). I started performing these in late 2003 and presented this as well as the fistula closure work at Digestive Disease Week in 2004
1and subsequently published results of the initial series in 2006.
- Thompson C.
- Carr-Locke D.
Novel endoscopic approaches to common bariatric postoperative complications.
Gastrointest Endosc. 2004; 59: P3
- Thompson C.C.
- Slattery J.
- Bundga M.E.
- et al.
Peroral endoscopic reduction of dilated gastrojejunal anastomosis after Roux-en-Y gastric bypass: a possible new option for patients with weight regain.
Surg Endosc. 2006; 20: 1744-1748
The idea of endoscopic suturing for weight loss was novel enough that I patented the concept of techniques for these “bariatric endoscopy” procedures as a new method (Fig. 2).
3We then licensed the patent to Bard, which in turn helped fund the endoscopic suturing studies that we were doing at the time, including gastrogastric fistula closures, outlet reductions for weight regain, outlet reductions for dumping syndrome, oversewing of marginal ulcers, and ultimately primary endoscopic therapies for weight loss and the predecessor to ESG.
- Thompson C.C.
Endoscopic gastric bypass defect repair. US Patent No. 8,623,009.
US Patent and Trademark Office, Washington, DC2014
PSG: So, your initial pioneering work with gastrogastric fistulas naturally led to the development of TORe. How did that step come about and were there challenges that you had to overcome?
CCT: The key lesson here is one that I’ve taught every subsequent fellow, and that is to learn to view advanced endoscopy from a disease standpoint, because if you understand the physiology and pathophysiology of disease, that trains your mind to be able to think about novel therapies rather than just randomly or aimlessly trying things. From our TORe experience, we realized that we had to figure out the pathophysiology of weight regain after RYGB, which has to do with a dilated outlet. Technically, the outlet is basically like a fistula that was a bit farther downstream. Interestingly, the size of the gastrojejunal anastomosis/outlet didn’t seem to be a major factor in dictating the patient’s initial weight loss after RYGB, but it did seem to be a significant factor contributing to weight regain in some patients. We learned a lot about the outlet and postulated that reducing the outlet size would allow patients to lose weight. I remember one of my initial presentations on the topic in 2005 at the American Society for Bariatric Surgery (the predecessor to what is now known as the American Society for Metabolic and Bariatric Surgery), where this idea was met with significant resistance from the surgeons who believed that RYGB was permanent and that outlet reduction wouldn’t work from a mechanistic standpoint.
With our hypothesis in mind, we started performing TORe and conducted a large, prospective, double-blind, randomized, sham-controlled trial that provided level 1 evidence for the procedure.
4Our initial procedures were performed with the EndoCinch, and even though the efficacy signal was good, the initial durability wasn’t great because the EndoCinch stitches were only partial thickness, whereas today we have full-thickness suturing and much better durability. But over time, TORe has continually evolved and has clearly become an important procedure for the management of weight regain after RYGB (Fig. 3).
- Thompson C.C.
- Chand B.
- Chen Y.K.
- et al.
Endoscopic suturing for transoral outlet reduction increases weight loss after Roux-en-Y gastric bypass surgery.
Gastroenterology. 2013; 145: 129-137
TORe is really the perfect example of how you can innovate a new procedure and continually improve on it. We started by gaining an understanding of the underlying pathophysiology of the condition and mechanisms of action for the proposed procedure. We began using interrupted sutures. We then gained understanding of mucosal healing and the limitations of endoscopically placed sutures. We subsequently started preparing the mucosa by adding argon plasma coagulation before endoscopic suturing. Then we improved our suture pattern with the advent of purse-string TORe. We further improved our tissue preparation by adding a modified endoscopic submucosal dissection of the outlet before purse-string TORe. Over serial improvements and iterations, we have taken the procedure from 3% total weight loss to 12% total weight loss, and we’re still continuing to improve the procedure.
PSG: Moving onward, the success of TORe seemed to naturally lead to the development of ESG, and 2022 marked the 10th anniversary of the first ESG for primary weight loss that you performed with Rob Hawes. Tell us a little about how ESG came about.
CCT: The original idea for primary endoscopic therapy was already there from our experience closing gastrogastric fistulas and making outlets smaller. But it was a further stretch because now we had a whole stomach to work with. There were actually 2 groups working on this. Roberto Fogel (Hospital de Clinicas, Caracas, Venezuela) was working on an endoscopic analogue of vertical banded gastroplasty called endoluminal vertical gastroplasty, in which he would take 1 running suture and create a vertical sleeve along the lesser curvature (Fig. 4).
5At the same time, I was working on an endoscopic analogue of gastric imbrication, a surgery primarily performed in Central and South America, in which we would take multiple running sutures and pull the greater curvature in onto itself.
- Fogel R.
- de Fogel J.
- Bonilla Y.
- et al.
Clinical experience of transoral suturing for an endoluminal vertical gastroplasty: 1-year follow-up in 64 patients.
Gastrointest Endosc. 2008; 68: 51-58
6In the United States, the Cleveland Clinic had the most surgical experience, so I partnered up with their surgical group, traveling back and forth to work on animal models to develop the procedure.
- Galvao Neto M.
- Zundel N.
- Campos J.
- et al.
Endoluminal greater curvature plication: a case series.
Obes Surg. 2013; 23: 1028-1029
This greater curvature gastric remodeling procedure was the immediate predecessor to ESG. We performed the first in-human procedures in 2008 as part of a trial called TRIM (Transoral gastric volume Reduction as Intervention for weight Management) (Fig. 5).
7At the time, we were using a second-generation Bard suction-based suturing device called the RESTORe device. Again, we weren’t getting full-thickness stitches that contributed to significant suture loss, but there was a good short-term efficacy signal that was encouraging.
- Brethauer S.A.
- Chand B.
- Schauer P.R.
- et al.
Transoral gastric volume reduction for weight management: technique and feasibility in 18 patients.
Surg Obes Relat Dis. 2010; 6: 689-694
Then in 2012, the second-generation OverStitch device (Apollo EndoSurgery, Austin, Tex, USA) became available. I had been peripherally involved with the development of the first generation and its predecessor, the EagleClaw, which were general multipurpose suturing devices with an eye toward NOTES access closures and perforation closures, which I then extrapolated to bariatric endoscopy.
In this case, the technology eventually caught up to what we had envisioned, and thus ESG was born. I performed the first in-human ESGs in Calcutta, India on April 29, 2012, with Dr Robert Hawes assisting and a small team from BWH and Apollo Endosurgery in attendance (Fig. 6).
- Kumar N.
- Sahdala H.N.
- Shaikh S.
- et al.
Endoscopic sleeve gastroplasty for primary therapy of obesity: initial human cases.
Gastroenterology. 2014; 5: 571-572
- Kumar N.
- Abu Dayyeh B.K.
- Lopez-Nava Breviere G.
- et al.
Endoscopic sutured gastroplasty: procedure evolution from first-in-man cases through current technique.
Surg Endosc. 2018; 32: 2159-2164
PSG: Is ESG still evolving as a procedure today?
CCT: Absolutely. I believe it was the following year that Dr Barham Abu Dayyeh and the Mayo team published the use of interrupted sutures to perform the procedure. These were ultimately added to the procedure as reinforcing sutures, and it continued to evolve. Now a “U” stitch pattern has largely replaced the original triangular stitch pattern; however, the underlying principle remains the same since the original TRIM and ESG procedures in that we use running sutures to reduce the greater curvature in an attempt to narrow the width and shorten the length of the stomach. There are still clearly some limitations to ESG in its current form. There is variability in the technical performance of the procedure with regard to number of sutures, number of stitches per suture, and types of stitch patterns. There’s also an issue of durability (ie, stitches falling out), and whether you are consistently affecting gastric motility. These issues are likely impacting the clinical results. There are also many other suturing and plication platforms that are now available or in clinical trials, such as the Incisionless Operating Platform (USGI Medical, San Clemente, Calif, USA [Fig. 7]) and the Endomina system (EndoTools Therapeutics, Brussels, Belgium) (Fig. 8), among others.
10We also need to think more about patient selection and personalized approaches to therapy.
- Jirapinyo P.
- Thompson C.C.
Endoscopic bariatric and metabolic therapies: surgical analogues and mechanisms of action.
Clin Gastroenterol Hepatol. 2017; 15: 619-630
PSG: A common theme to your innovativeness is a deep understanding of pathophysiology and mechanisms of action. Let’s expand on that a bit further.
CCT: It is incredibly important to understand pathophysiology so that you can achieve a direct treatment effect. It is also important to understand mechanisms of action because you can potentially use these mechanisms to alter normal physiology to achieve a treatment effect without directly addressing the underlying pathophysiology. For example, it’s hypothesized that the proximal small bowel has an active role in the pathophysiology of obesity and insulin resistance involving local inflammation, leaky tight junctions, and dysregulation of the neurohormonal axis. Potential ways to directly address this proposed small-bowel pathology is with duodenal mucosal resurfacing (Fractyl, Lexington, Mass, USA) (Fig. 9)
- Galvao Neto M.P.
- Rodriguez L.
- Becerra P.
- et al.
Hydrothermal duodenal mucosal resurfacing: a novel procedural therapy for metabolic disease.
VideoGIE. 2016; 1: 10-11
12, which ablates the involved tissue so that it comes back healthier, to block the area with a duodenal jejunal bypass liner (EndoBarrier, GI Dynamics, Boston, Mass, USA), or to manipulate the neurohormonal axis with various emerging devices.
- Haidry R.J.
- van Baar A.C.
- Galvao Neto M.P.
- et al.
Duodenal mucosal resurfacing: proof-of-concept, procedural development, and initial implementation in the clinical setting.
Gastrointest Endosc. 2019; 90: 673-681
On the other hand, with gastric procedures, we are altering normal gastric physiology to achieve a treatment effect without necessarily treating the underlying pathophysiology of obesity. Recall that digestion occurs in 3 distinct phases. In the first phase, the fundus stretches to accommodate food. In the second phase, the food is mixed and broken down. In the third phase, the food is emptied out of the stomach. If we think about how devices work, the original primary obesity surgery endoluminal (USGI Medical) procedure focused only on accommodation and most of the plications went into the fundus to create early satiation. ESG impacts both accommodation and grinding and breakdown of food. The transpyloric shuttle directly impacts the antral pump and delays emptying. Nevertheless, these devices are not directly addressing the underlying pathophysiology of obesity but are altering normal physiology to achieve weight loss.
This understanding is what led us to our most recent iteration of ESG, termed “gastroplasty with endoscopic myotomy,” which we first performed in 2021.
13In this new procedure we start by performing a pylorus-sparing antral myotomy to inhibit the antral pump and delay gastric emptying and subsequently perform an abbreviated ESG to address the first and second phases of digestion. By leaving the pylorus intact and focusing on the antrum, the myotomy has the opposite effect of a gastric peroral endoscopic myotomy (POEM). We are preliminarily seeing a delay in gastric emptying with the half-life increasing from 90 to over 200 minutes. Addition of the antral myotomy is hypothesized to provide a more consistent delay in gastric emptying than suturing alone, improve technical variability, and also improve weight loss and durability. We believe this approach will enhance both satiety and satiation after the procedure. We are now studying the effect of antral myotomy alone, without ESG, and early results are encouraging. Again, the theme is using our understanding of physiology to guide innovation.
- Thompson C.C.
- Jirapinyo P.
- Shah R.
- et al.
Gastroplasty with endoscopic myotomy for the treatment of obesity: preliminary efficacy and physiologic results.
Gastroenterology. 2022; 163: 1173-1175
PSG: Despite serial improvements, ESG remains a technically challenging procedure that requires great expertise and familiarity with endoscopic suturing. How does one develop competency in ESG?
CCT: Fundamentally, ESG requires proficiency in endoscopic suturing. Without proficiency, it can take a very long time to complete the procedure, and you can become tired and run into technical issues and ultimately complications (such as bleeding, mural hematomas, etc). But once one develops proficiency in endoscopic suturing, ESG is not exceedingly difficult, but more so that it’s time consuming.
However, this leads to a larger question of how we train bariatric endoscopy in general. In our Bariatric Endoscopy and Foregut Endosurgery Fellowship, we have a formal curriculum covering the cognitive aspects of obesity management and the technical elements for all endoscopic bariatric and metabolic therapies. Specifically, for ESG, we first train our fellows to be proficient on endoscopic suturing simulators that we have developed and validated. We then advance our fellows to clinical TORe cases. This is because performing purse-string TORe is actually more technically demanding than ESG but is a shorter procedure (1 suture with roughly 14 stitches and 1-2 reinforcing sutures). Furthermore, TORe is fundamentally safer from a training standpoint. After our fellows have become comfortable with the purse-string TORe, we move them to ESG, and by then they’re very well prepared for the challenge and can more efficiently perform the procedure.
Admittedly, we haven’t fully solved the training issues in bariatric endoscopy. Training practicing clinicians with various backgrounds and experience levels is complicated. We have developed the first textbook on bariatric endoscopy,
- Thompson C.C.
Springer Science & Business Media. New York: Springer, 2013
15and annual hands-on and live endoscopy courses (Flexible Endoscopic Surgery and Bariatric Endoscopy, Miami Beach, and Bariatric Endoscopy Live-Global), but more is needed. It will ultimately require a more active role from our professional societies and industry partners. This is why we started the Association for Bariatric Endoscopy (ABE), for which I had the honor of being the founding chairperson (Fig. 10). Through ABE training programs and guidance, documents are being developed. Several other societies are now starting to provide training solutions as well.
- Thompson C.C.
Endoscopy in the bariatric patient.
ASGE Endoscopic Learning DVD Library. Downers Grove: American Society for Gastrointestinal Endoscopy, 2007
PSG: Training issues aside, the uptake of bariatric endoscopy procedures has been relatively slow (as opposed to, say, EUS-guided cystogastrostomy). What have been the barriers to adoption?
CCT: I believe the adoption rate has been fairly similar to direct endoscopic necrosectomy and other advanced endoscopic procedures. When I started doing necrosectomies in 2003, there were only a few centers across the country performing the procedure. Even with the development of lumen-apposing metal stents, very few centers clinically offered the procedure until Boston Scientific acquired the technology and started to more aggressively promote the technique. It took well over a decade before the procedure was performed in most academic medical centers, and we are not too far off from this in bariatric endoscopy; however, there are some unique challenges.
It’s really a 2-fold problem. First, there’s the learning curve, which is both cognitive and technical. Gastroenterologists often need to learn about the basics of obesity and how to care for these patients, as well as patient selection and preoperative and postoperative care.
16Endoscopic suturing is also a rather unique skillset in the world of therapeutic endoscopy and probably has a longer learning curve than other new techniques. The second is reimbursement and infrastructure. To have a successful practice, you need an infrastructure capable of taking care of patients with obesity. You need to make sure they’re properly cleared for their procedure, that preapprovals are obtained, and that they’re properly followed-up after their procedure. You need to work closely with a multidisciplinary team to achieve this because you really don’t want people to have these procedures done without proper follow-up and overall medical care for their obesity. You need to work closely with dieticians, psychologists, medical bariatricians, endocrinologists, bariatric surgeons, and patient navigators. Most gastroenterology practices, unless they are part of an integrated weight management center, unfortunately simply don’t have that sort of infrastructure.
- Jirapinyo P.
- Thompson C.C.
Obesity primer for the practicing gastroenterologist.
Am J Gastroenterol. 2021; 116: 918-934
PSG: If reimbursement has been a barrier to adoption in the United States, does that mean bariatric endoscopy has been more widely adopted and embraced in other countries around the world?
CCT: Obesity is a global pandemic with an overall higher prevalence than colorectal cancer. There are certain countries where bariatric endoscopy is perhaps more developed. In particular, there are countries in Europe, the Middle East, and South America that have rather robust bariatric endoscopy practices. In some of these regions, intragastric balloons are very common.
PSG: How did gastric balloons fit into all of this?
CCT: In the early 2000s, intragastric balloons were not really in the picture. It is interesting to note that the concept has been around since the Garren-Edwards gastric bubble in the 1980s. However, balloons kind of came and went. Early balloons had a lot of complications, and weight loss was unsatisfactory, which led to them being available for only a couple of years before disappearing off the market. Modern balloons are safe, and there are many patients who benefit from them for various reasons. However, to me, it took more than just balloons to create a new field. Rather, creating a new field required developing various new technologies and new procedures.
PSG: Aside from bariatric endoscopy, you’ve also been a pioneer in multiple other areas of endoluminal surgery and have started several companies. How has your expertise and understanding of other aspects of therapeutic endoscopy influenced your advancements in bariatric endoscopy?
CCT: Bariatric endoscopy represents approximately 50% of my clinical and academic efforts. There are all sorts of unexpected benefits to cross-pollination. A little bit of background here: When I was right out of fellowship, I was fortunate enough to receive a career development award from the ASGE to cross-train in surgical techniques with Dr David Rattner at Massachusetts General Hospital. That allowed me to better understand surgical principles and how surgeons view different procedures, anatomy, and pathophysiology. That was very instrumental in my early career development. Along with that, I also had grants to explore NOTES, doing a lot of work in the animal laboratory on transgastric cholecystectomy, distal pancreatectomy, and other very advanced NOTES procedures, and I was fortunate to be a co-founder of NOSCAR (Fig. 11). This led to us studying new technologies, including various multitasking platforms like robotic devices, closure devices, and new procedures.
As you know, although transluminal NOTES procedures never quite became mainstream, NOTES generated a lot of procedures like POEM and necrosectomy. POEM, for instance, was simply a means of accessing the peritoneal cavity. We would create tunnels in the submucosal space so we could do a procedure in the abdomen and then come back through the tunnel to safely close the access site. Full-thickness resection, suturing platforms, all these NOTES technologies ultimately came back into endoluminal procedures. And so that initial cross-training I had was very informative and really shaped the rest of my career.
I also found that spinning technologies out of the laboratory into startup companies was often a more efficient way to complete their development and move them into clinical practice. Startup companies are an entirely different skillset to master but are an important part of innovation. Knowing which technologies are devices that should be licensed and which can be standalone companies is important to their ultimate success. I have been fortunate to have co-founded several successful startups and have found the most important part to be the people. Having a strong team that is effective and that you can trust is critical. Corporate structure and governance, fund raising, technology development, and regulatory aspects to this process are not typically learned in medical training but are essential to the development of nascent fields such as this. We try to expose interested fellows to this process as much as possible. An example here is the development and commercialization of a novel metabolic procedure that uses self-assembling magnets (GI Windows, Westwood, Mass, USA) to create a duodenoileal side-to-side anastomosis for dual-path enteral diversion (Fig. 12).
- Machytka E.
- Buzga M.
- Zonca P.
- et al.
Partial jejunal diversion using an incisionless magnetic anastomosis system: 1-year interim results in patients with obesity and diabetes.
Gastrointest Endosc. 2017; 86: 904-912
At the same time, it is important to develop and maintain your core skills because you just never know when those skills will cross over. When you’re initially building a bariatric endoscopy practice, you’re dealing with complications from surgical procedures and may need to know how to place stents, perform pneumatic balloon dilations, do ERCPs, etc. Similarly, the ability to place stents fluoroscopically translates into placing duodenal jejunal bypass liners and ablation catheters for small-bowel procedures. Finally, some of the newer iterations of our bariatric procedures, like endoscopic submucosal dissection TORe and gastroplasty with endoscopic myotomy, are combining third-space procedures with bariatric suturing to achieve better results.
PSG: In reflecting on how far the field of bariatric endoscopy has come, where do you believe the field is headed?
CCT: Technology will continue to evolve as we have seen, making the procedures easier to perform. As far as endoscopic surgery is concerned, the inventions that have probably been the most impactful have been full-thickness suturing and plication, improved electrosurgical unit generators and waveforms, injection-type electrosurgical knives, and lumen-apposing metal stents. These technologies have made a significant impact in the way endoscopic surgical procedures are performed and in broadening their adoption. I suspect we will see more of this in bariatric endoscopy as well.
I believe there are a few specific areas that are going to help drive this field forward. One hot area of research is personalized medicine and gaining a better understanding of who is likely to respond to what therapies. The other area is the role of combination therapies. For example, a procedure focusing on the stomach paired with a procedure focusing on small-bowel mechanisms. Or a combination of a procedure plus a medication. We have early combination-therapy studies on TORe with medications and on ESG with medications, and these are very encouraging.
Additionally, as we better understand the pathophysiology of obesity, we will have procedures that are more targeted, more consistent, and more durable. The other aspect will be broader acceptance. We may have randomized controlled trials, large case series, meta-analyses, and cost studies, and all of them may speak to safety and effectiveness, but even that might not necessarily translate to acceptance across various medical disciplines or to proper reimbursement. Our professional societies and industry partners will likely need to play a more active role here.
PSG: For a lot of us who have had the benefit of training with you, a common theme has been a genuine reverence for how you’re able to constantly think outside the box. Was this something you were always able to do since you were young? Or was this something that was developed, trained, and encouraged?
CCT: I guess I have been thinking outside the box since I was young. Taking apart clocks and toys and almost anything to figure out how they work, etc. However, it was during my advanced endoscopy fellowship that it was really encouraged and developed. Dr William Brugge had assigned me several research and developmental projects that constantly pushed me to go outside my comfort zone. That’s how it really started to take shape. Dr Brugge encouraged me to try not necessarily harder or longer but to think differently and outside the box. We were doing stuff like direct portal pressure measurements, injecting pancreatic cysts with ethanol, and inventing core biopsy needles. In many ways, he was opening my eyes in terms of thinking about whole new ways to do things. That mentality is contagious, and that’s really when I started focusing on innovation.
PSG: In medicine, professional satisfaction is critically important to keep us grounded and motivated and to prevent burnout. What drives you to contribute every day?
CCT: It’s fulfilling to help patients. I feel really bad when I see patients in despair, and it drives me to solve their problems and relieve their suffering. When patients don’t have any options left, it drives me to innovate. From a bariatric endoscopy standpoint, although we get great results, there are very few practices that are doing this effectively, so I’m constantly driven to figure out better ways to do this, to make the procedures more durable, to shorten the learning curve, and allow for broader adoption. So many people suffer from obesity and simply don’t have access to proper care. There’s much work to do and the job is not done.
PSG: How do you view mentorship and your ongoing relationship with your mentees?
CCT: Mentorship is typically a lifelong commitment, and over “generations” a training program certainly does feel like a family. We had the first Bariatric Endoscopy and Foregut Endoscopic Surgery Fellowship program starting well over a decade ago and have trained over 30 fellows (Fig. 13). This has been very fulfilling and is a great way to build the field. The individual relationships evolve over time with each mentee as their career develops. Helping each mentee develop their career also helps develop and grow the field. As mentees come through, they learn a skillset that they will go out into the world and use to help individual patients, and hopefully they will pay it forward by training others. While they’re here and hopefully after they leave, they’re also doing groundbreaking research that helps develop the field in other ways. That youthful energy encourages us as mentors to drive the field forward. Mentees are important building blocks as we construct our field; with every mentee comes a new opportunity, a new way to see things, and it really benefits society as a whole to actively train the next generation.
The relationship takes on a different role at the junior faculty stage. To give a personal example, when I was early in my career (first several months in), we got into some pretty bad bleeding during our early fistula closures. I recall a particularly traumatic case in which the patient bled 9 units on the table. It was traumatic for the entire unit, but my mentor was ultimately able to stop the bleeding. I was distraught and told my mentor afterward that I honestly believed it was over. His response—“it's your decision, but this is an important point in your career: You can decide to not innovate anymore and be a really great high-quality endoscopist. But if you want to be a pioneer, this is the point at which you need to get back on the horse, learn from the procedure, and harden your resolve to make it better.” That was really sage advice. A good mentor in this regard knew when to push me when I needed a push, and to be a pioneer, you need a good mentor who will support you in that regard, who knows they can help you, who feels comfortable in their skillset, and is also willing to let you grow. Looking back, that was a pivotal point in the development of my career and a pivotal point in the development of the entire field.
PSG: What advice do you have for your mentees who are interested in innovation and investigation in GI endoscopy?
- 1.Make sure you develop and maintain very strong fundamentals (tip control, etc).
- 2.Understand and acknowledge your limits. Everyone has a limit, but the greater your awareness, the more you can safely push your boundaries and improve.
- 3.Make sure you keep an open mind. Think outside the box.
- 4.Remember that at the end of the day, the patient comes first, and you’re doing it for the patient and not for yourself.
This article includes an accompanying recorded video interview with Dr Christopher C. Thompson (Supplemental Video 1, available online at www.igiejournal.org).
The authors and editors acknowledge Ms Kaylee Dellert for the creation of Figure 1.
The following authors disclosed financial relationships: C. C. Thompson: Consultant for Apollo Endosurgery, Boston Scientific, Covidien/Medtronic, Enterasense Ltd, EnVision Endoscopy, Fractyl, GI Dynamics, GI Windows, Olympus/Spiration, USGI Medical, Fujifilm, and Lumendi; research support from Apollo Endosurgery, Aspire Bariatrics, Boston Scientific, Erbe, GI Dynamics, Olympus/Spiration, USGI Medical, Fujifilm, and Lumendi; general partner with BlueFlame Healthcare Venture Fund; founder of and board member for Enterasense Ltd, EnVision Endoscopy, and GI Windows; advisory board for Fractyl and USGI Medical. P. Jirapinyo: Consultant for Erbe, Endogastric solutions, and Spatz; research support from Apollo Endosurgery, Boston Scientific, Fractyl, GI Dynamics, and USGI Medical. P. Ge: Consultant for Boston Scientific, Ovesco America, and Alira Health. All other authors disclosed no financial relationships.
- Novel endoscopic approaches to common bariatric postoperative complications.Gastrointest Endosc. 2004; 59: P3
- Peroral endoscopic reduction of dilated gastrojejunal anastomosis after Roux-en-Y gastric bypass: a possible new option for patients with weight regain.Surg Endosc. 2006; 20: 1744-1748
- Endoscopic gastric bypass defect repair. US Patent No. 8,623,009.US Patent and Trademark Office, Washington, DC2014
- Endoscopic suturing for transoral outlet reduction increases weight loss after Roux-en-Y gastric bypass surgery.Gastroenterology. 2013; 145: 129-137
- Clinical experience of transoral suturing for an endoluminal vertical gastroplasty: 1-year follow-up in 64 patients.Gastrointest Endosc. 2008; 68: 51-58
- Endoluminal greater curvature plication: a case series.Obes Surg. 2013; 23: 1028-1029
- Transoral gastric volume reduction for weight management: technique and feasibility in 18 patients.Surg Obes Relat Dis. 2010; 6: 689-694
- Endoscopic sleeve gastroplasty for primary therapy of obesity: initial human cases.Gastroenterology. 2014; 5: 571-572
- Endoscopic sutured gastroplasty: procedure evolution from first-in-man cases through current technique.Surg Endosc. 2018; 32: 2159-2164
- Endoscopic bariatric and metabolic therapies: surgical analogues and mechanisms of action.Clin Gastroenterol Hepatol. 2017; 15: 619-630
- Hydrothermal duodenal mucosal resurfacing: a novel procedural therapy for metabolic disease.VideoGIE. 2016; 1: 10-11
- Duodenal mucosal resurfacing: proof-of-concept, procedural development, and initial implementation in the clinical setting.Gastrointest Endosc. 2019; 90: 673-681
- Gastroplasty with endoscopic myotomy for the treatment of obesity: preliminary efficacy and physiologic results.Gastroenterology. 2022; 163: 1173-1175
- Bariatric endoscopy.Springer Science & Business Media. New York: Springer, 2013
- Endoscopy in the bariatric patient.ASGE Endoscopic Learning DVD Library. Downers Grove: American Society for Gastrointestinal Endoscopy, 2007
- Obesity primer for the practicing gastroenterologist.Am J Gastroenterol. 2021; 116: 918-934
- Partial jejunal diversion using an incisionless magnetic anastomosis system: 1-year interim results in patients with obesity and diabetes.Gastrointest Endosc. 2017; 86: 904-912
Accepted: October 30, 2022
Received: October 19, 2022Section Editor: Phillip S. Ge, MD
© 2022 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc.
User licenseCreative Commons Attribution – NonCommercial – NoDerivs (CC BY-NC-ND 4.0) |
How you can reuse
Elsevier's open access license policy
Creative Commons Attribution – NonCommercial – NoDerivs (CC BY-NC-ND 4.0)
For non-commercial purposes:
- Read, print & download
- Redistribute or republish the final article
- Text & data mine
- Translate the article (private use only, not for distribution)
- Reuse portions or extracts from the article in other works
- Sell or re-use for commercial purposes
- Distribute translations or adaptations of the article
Elsevier's open access license policy