It is important to understand the past in order to innovate into the future. Procedural fields are well known for devices named after their original inventors, from Kelly clamps and Bookwalter retractors in surgery to the Amplatz guidewire in interventional radiology. Although several such devices exist in gastroenterology as well, arguably none is more famous and more universal than the Roth Net. In everyday gastroenterology practice, the term “Roth Net” is essentially used to describe retrieval nets made by any manufacturer, making the humble yet venerable retrieval net perhaps the single most famous endoscopic device in mainstream gastroenterology practice. Simple yet elegant in its concept, the advent of the Roth Net embodies the spirit of innovation in GI endoscopy. We are therefore honored and delighted to have the opportunity to interview Bennett E. Roth, MD, MASGE, as our distinguished guest for the Historical Considerations section of iGIE (Fig. 1, Video 1, available online at www.giejournal.org). Dr Roth is arguably one of the original endoscopists and innovators in our field. In addition to the eponymous retrieval net that he invented in 1983, Dr Roth has taught the rest of us what it means to be a consummate gastroenterologist. Over a long career in both academic and private practice (and then back to academic practice), Dr Roth embodies a spirit of lifelong learning, as a passionate gastroenterologist who is simultaneously a master generalist, specialist, and endoscopist. Dr Roth has served in numerous high-profile administrative roles, including as Clinical Chief of the University of California, Los Angeles Division of Digestive Diseases, and President of the American Society for Gastrointestinal Endoscopy (ASGE) in 1994 to 1995. Even in retirement, he has continued to mentor junior faculty while keeping up with developments and advances in the field that he so deeply loved and profoundly impacted. Phillip S. Ge, MD iGIE Section Editor for Historical Considerations Phillip S. Ge (PSG): Dr Roth, thank you so much for taking the time to provide this interview. It is truly an honor and privilege. You have been a pioneer for most of your career, partly because you have a pioneering spirit, but also partly because quite frankly you did not have much of a choice as you joined a field that was still in its infancy. Tell us about what the field of gastroenterology was like when you started your training. Bennett E. Roth (BER): When I started my training in gastroenterology, we really were in the early phases of endoscopy. Gastroenterology at the time was primarily a science and art of taking the right history, doing the right physical examination, and then making an assumption based on history, examination, and basic laboratory studies. Short of surgical exploration or simply the passage of time, there was no other way of knowing whether the diagnosis was correct or not. Consider this: Back during my training, when a patient came in with jaundice, we had to determine whether their jaundice was intrahepatic or extrahepatic. So we would pass a needle percutaneously into the liver under fluoroscopic guidance. And as we pulled the needle back, we would exert slight negative pressure to see if we got some bile and then inject contrast. If we withdrew bile, we would inject in that spot to basically get a percutaneous cholangiogram to see what the ducts looked like. If we got no bile back, we would basically assume under those circumstances that the jaundice was hepatocellular and not obstructive, basically that it was not a pancreaticobiliary malignancy. We relied on this information and operated on people in whom we suspected biliary obstruction.1Shaldon S. Barber K.M. Young W.B. Percutaneous transhepatic cholangiography. A modified technique.Gastroenterology. 1962; 42: 371-379Abstract Full Text PDF PubMed Scopus (33) Google Scholar We were correct 60% of the time. I remember another example when I was a resident, listening to a lecture by one of the premier gastroenterologists at the University of Pennsylvania on the management of colonic polyps found on barium enema. If the polyp was 1 cm or less, you would repeat the barium enema in a year. If the polyp was more than 1 cm, or if it changed in the course of the year, you would operate. That was the standard management of colonic polyps in the 1970s.2Leffall Jr., L.D. Chung E.B. Surgical management of colorectal polyps.Cancer. 1974; 34: 940-947Crossref Scopus (4) Google Scholar PG: A very different world indeed. As I understand it, endoscopy started while you were in training. How did you become involved in endoscopy? BR: Endoscopy changed everything. It was with the advent of endoscopy that we really made the giant step forward of seeing what the gut looked like and what sort of disorders were present that we could visualize for the first time. But it was not universally available. In the early days, deciding who to perform an endoscopy on reminded me of being a resident on the nephrology service deciding who to put on hemodialysis. It was a very big decision. Endoscopes were limited in availability, and they were not quite as maneuverable. It was not quite as easy to intubate the esophagus. There were not very many teachers either, and so I was essentially self-taught in endoscopy. I remember as a fellow at UCLA (University of California, Los Angeles), we had 3 scopes—a gastroscope, a side-viewing duodenoscope for the first attempts at ERCP, and a colonoscope. The gastroscope broke 6 weeks into my fellowship, and we had to send it back to Japan for repair. Over the 6 to 8 weeks where the gastroscope was gone for repair, I was forced to perform all of my upper endoscopies using a side-viewing duodenoscope. So I got a little bit of initial instruction from Richard F. Corlin, MD, who was a fellow 3 to 4 years before me and who was in practice in Santa Monica, and Robert C. Goldstein, MD, who was a fellow 1 year before me. I got some very basic instruction information from them, and soon got pretty adept at doing endoscopy using an instrument that was really developed for something different. So when it came time to perform ERCP, I was already pretty good at getting the scope en face and facing the papilla. So it was a blessing in disguise. PG: It must have been interesting to become a pioneer in endoscopy as a fellow, with none of your senior attendings knowing how to perform endoscopy. Was there resistance to the introduction of endoscopy at the time? BR: At the time, it was a battle between the highly respected gastroenterology faculty around the country and us new guys who were derisively referred to as “scope jockeys.” There was a famous cartoon that circulated around with elephants with scopes rather than trunks, standing in a circle scoping each other, as a put-down on people who did endoscopy versus those who were stellar clinicians and good thinkers. But it did not take long until everyone began to realize the value of upper and lower endoscopy. Once that realization came, the science and practice of gastroenterology completely changed. PG: After your fellowship training, you were hired as junior faculty at UCLA. Tell us about the early days of being on faculty. BR: I was the first person who was hired on faculty who was trained in endoscopy.3Lewis M. Bennett E. Roth, MD. J Clin Gastroenterol. 2003; 37: 275-277Crossref Scopus (0) Google Scholar With the exception of a few cases that Richard Corlin did, I basically became the first faculty member at UCLA to perform endoscopy and the first person at UCLA who performed ERCP as a fellow. It is really hard to imagine this nowadays, but at the time I did not have any real formal training in technique, because nobody was really all that adept in ERCP in the United States. The European and Japanese endoscopists were ahead of us, and many people traveled to Europe or Japan a few weeks at a time to observe and learn. ERCP at the time was purely diagnostic; there was no papillotomy, no stenting, none of the things that would seem standard today. I ended up doing endoscopy and ERCP simply because nobody was around at UCLA who could do it. So, in my first 3 to 4 years as a junior faculty member, I essentially performed or shepherded every endoscopic procedure at UCLA. PG: As an early pioneer in endoscopy, tell us about the endoscopy unit at the time. How were cases done at the time? BR: At the time, we had 2 fellows and a single-bed endoscopy unit with a recovery area in the hospital that we used for both inpatients and outpatients. We rarely had any anesthesia coverage. Procedures were either done without sedation in some cases or with a combination of meperidine and diazepam. After outpatient upper endoscopy, patients recovered for about an hour and were then driven home. Colonoscopy was also a procedure that was really just getting off the ground. At the time, the performance of a colonoscopy entailed a 3-day hospital stay. On day 1, the patient would be admitted to the hospital and placed on a liquid diet. On day 2, they were given a laxative. We did not have polyethylene glycol-3350 (GoLYTELY, Braintree Laboratories, Braintree, Mass, USA) at the time, so they received primarily a magnesium citrate–based bowel preparation. The procedure was then performed on day 3. If all went well and the patient was comfortable, they would be sent home that night. So every procedure regardless of what was planned or anticipated was associated with a minimum 3-day hospital stay. It was only with time that Medicare and insurance companies eventually agreed to pay for true outpatient endoscopy where patients would cleanse at home, be put on a liquid diet for as much as a week in advance, and then would come in the morning of the procedure. Endoscopy at the time also included diagnostic laparoscopy/peritoneoscopy. It is quite funny to think about natural orifice transluminal endoscopic surgery nowadays because we were doing aspects of that in the very beginning! We would perform 3 to 5 of those cases a week in the endoscopy unit for various indications: evaluation of unexplained ascites, diagnosis of peritoneal metastases, diagnosis of peritoneal tuberculosis, and for liver biopsy sampling when patients had risk factors that were prohibitive for traditional percutaneous liver biopsy sampling. I actually learned a great deal about laparoscopy from Telfer B. “Pete” Reynolds, MD, a highly respected hepatologist who directed the renowned Los Angeles County–University of Southern California Liver Unit. With the assistance of George Berci, MD, a highly respected surgeon and endoscopist from Cedars-Sinai Medical Center (and who is still alive and practicing at 101 years old!), we put on an annual course for training fellows and practicing gastroenterologists on the use of laparoscopy. Ultimately, most of these indications went away with the advent of CTs, which allowed radiographic guidance for percutaneous procedures. PG: Given that you were one of very few people who knew how to perform endoscopy, how did that influence your practice and did it focus primarily on endoscopy? BR: Surprisingly not, and I think it had a lot to do with the way that I viewed endoscopy. I have always seen a very broad population of patients, first at UCLA, then in private practice, and ultimately back at UCLA. I saw patients with inflammatory bowel disease, patients with functional bowel disorders, swallowing disorders, recalcitrant acid reflux issues, and also ran a gastroparesis clinic in which I assessed patients to determine optimal management including their candidacy for gastric stimulators. Nowadays, with the complexity and time involved in many of the advanced endoscopy procedures, it has become necessary to have some of our team concentrate as interventionalists. But I really enjoyed having a broad practice, where I interviewed and evaluated every patient. So in that sense, I practiced gastroenterology, and I viewed endoscopy as a means to an end. PG: Viewing endoscopy as a means to an end is a really important mindset and one that I sincerely hope will continue to resonate with younger generations. I also admire your tremendous courage to become a pioneer in such a nascent field. In the early days of your career, did you ever have doubts about the future of endoscopy? Did you ever wonder to yourself what if the technology did not pan out? BR: You know, I never really thought about that. I suppose I just never really doubted the value of endoscopy, and that if endoscopy did not pan out for some reason, I would have had to find other ways to put food on the table. But I never really thought that this was something that would just be a passing fad and would go away and we would be back to the days of pipe smoking and musing about diagnoses. Endoscopy was a truly compelling advancement. The diagnosis and management of many diseases fundamentally changed with the use of endoscopy, and every day there was new reason to believe in its value. For example, you might not know that eosinophilic esophagitis was not even a known diagnosis in those early days.4Dobbins J.W. Sheahan D.G. Behar J. Eosinophilic gastroenteritis with esophageal involvement.Gastroenterology. 1977; 72: 1312-1316Abstract Full Text PDF PubMed Scopus (212) Google Scholar I remember when I had a patient with odd findings on endoscopy, with linear fissures that looked like red bricks. We were just becoming aware of this entity at the time, so I called H. Worth Boyce, MD, FASGE, a highly respected endoscopist and esophagologist, who had been one of the first to manage varices endoscopically. I called him, described the findings, and he said it was eosinophilic esophagitis. Biopsy samples confirmed the diagnosis. That was a clear example of the early value of endoscopy. The key thing really was figuring out how to best utilize endoscopy and the tools that you could then use to evaluate and treat these disorders. The old comment of “Oh you’re just an endoscopist” was total nonsense; on the contrary, you have to be a good gastroenterologist to know how to be a good endoscopist because you needed to have good fundamentals in order to know how to correctly use the tools and technologies at your disposal. PG: You mentioned the endoscopic management of varices. I would imagine that the advent of endoscopy seismically changed the diagnosis and treatment of GI bleeding. Tell us a bit about the endoscopic management of bleeding and the role you played in shaping the field. BR: Endoscopy changed the management of GI bleeding enormously. In the early days of endoscopy, we basically were only interested in and able to figure out one thing—where was the bleeding coming from and was the bleeding variceal or not. The earliest I remember anyone doing anything therapeutically was John P. Papp, Sr, MD, from Michigan State University, who pioneered some of the first techniques for endoscopic electrocoagulation for upper GI bleeding.5Papp J.P. Endoscopic electrocoagulation of upper gastrointestinal hemorrhage.JAMA. 1976; 236: 2076-2079Crossref PubMed Scopus (41) Google Scholar During my early years, Dennis “Dean” M. Jensen, MD, MASGE, was one of my fellows, and I am really pleased and proud to say that I shepherded him through his early endoscopy days. Dean dedicated his career toward evaluating and developing various modalities for management of GI bleeding, both variceal and nonvariceal, which ultimately changed the whole management of GI bleeding disorders. Mentoring Dean in his early fellowship days was probably my biggest contribution to the management of GI bleeding.6Dennis Jensen, MD.VideoGIE. 2020; 5: 1-4Abstract Full Text Full Text PDF PubMed Scopus (0) Google Scholar In the case of smart people like Dean, innovation came about because he understood physiology and pathophysiology and used that as his basis for finding ways to manipulate it to treat disease.7Jensen D.M. Cheng S. Kovacs T.O. et al.A controlled study of ranitidine for the prevention of recurrent hemorrhage from duodenal ulcer.N Engl J Med. 1994; 330: 382-386Crossref PubMed Scopus (99) Google Scholar PG: Tell me about the early days of endoscopic innovation. BR: In the early days of endoscopy, need was truly the mother of innovation. I remember my first ASGE committee assignment. I was assigned to the Standards of Practice Committee with Jerome D. Waye, MD, MASGE, who was the chair of the committee. At the time, Greg V. Stiegmann, MD, at the University of Colorado was reporting good results on the use of sclerotherapy for esophageal varices.8Terblanche J. Yakoob H.I. Bornman P.C. et al.Acute bleeding varices: a five-year prospective evaluation of tamponade and sclerotherapy.Ann Surg. 1981; 194: 521-530Crossref PubMed Scopus (137) Google Scholar,9Stiegmann G.V. Goff J.S. Michaletz-Onody P.A. et al.Endoscopic sclerotherapy as compared with endoscopic ligation for bleeding esophageal varices.N Engl J Med. 1992; 326: 1527-1532Crossref PubMed Scopus (647) Google Scholar The problem though was that the only injector at the time was made by Olympus for a semirigid scope that was short and rather large, making it suboptimal and difficult to use. Jerry (Waye) was toying with the idea of making his own injector needle, and the 2 of us were chatting and thinking about how we would do it. With Jerry’s thoughts and insights in mind, I came home from the meeting, took a 25-gauge needle and cut off the hub, glued it to a polyethylene catheter, fed the tube into a slightly larger circumference tube, and glued the remaining needle end into the distal end of the smaller tube, resulting in a retractable catheter with a protective sheath that we were able to use as an injector. It worked! Nothing fancy, but it worked. So not too long after, there was a meeting of the Southern California Society for Gastroenterology and Endoscopy. Michael V. Sivak, Jr, MD, MASGE, who was chief of gastroenterology at Mayo Clinic, gave a talk. I was the President of the Society and emcee at the time and casually mentioned something to the audience about having our own needles and starting to do sclerotherapy. Before I could fully realize the implications of what I had just said, we were inundated with referrals. It seemed as though the whole city of Los Angeles was sending variceal bleeders to us in the middle of the night—We were getting creamed! It did not take long before an accessory company took up the idea and made their own injector needle, and soon everyone had their own needle and the referral line thankfully ended. PG: It always amazes me to hear these stories, of how innovations seemed to flow so easily from an idea to clinical use. Was it really that easy? Did you always possess an innovative mindset that set you apart from others? Or was there something about the landscape that made it easy to innovate? BR: I think it was a bit of both. Looking back at my own upbringing, I always had a knack for innovation. If I needed to solve a problem or do something that required something that I did not have, whether it was knowledge, a technique, or a device, I always tried to see if I could come up with something. Again, the premise was that the need drives the invention. That’s the concept that led to the injector catheter and subsequently the retrieval net. But it was also partially the landscape. In those days we did not worry as much about medicolegal issues. I used the retrieval net on a patient for the first time when it was brought out as a prototype; we did not have institutional review boards or anything like that. In hindsight, it was probably wrong to do it that way, but glad to say it all worked out. The times have fundamentally changed. Nowadays there are more medicolegal issues, a more litigious society, and we simply cannot be as cavalier as we were. When I look back, we probably cannot do many of the same things that we did 30 years ago today. PG: It is obviously not possible to do this interview without talking about the Roth Net. Some aspects of the history of the retrieval net were covered in a previously published VideoGIE interview,10Bennett Roth, MD.VideoGIE. 2020; 5: 129-132Abstract Full Text Full Text PDF Google Scholar but I want to go into more depth on how this all came about. Having set the stage for innovation, let us talk about the development of the eponymous retrieval net that bears your name. BR: To be honest, I do not remember the exact circumstances at this point, but the idea likely stemmed from a difficult or frustrating experience from that day, probably the annoyance that I had to go back into the colon 6 times to retrieve every piece of the polyp I had cut. But that night I saw on a television commercial a guy using a net to pull fish out of the water and instantly connected the dots. Polyp retrieval presented a variety of challenges from a technical standpoint. Before the Roth Net, we relied on suctioning small polyps or bits and pieces of larger polyps, use of snares to gently grab larger polyps, or biopsy forceps for piecemeal removal.11Waye J.D. Lewis B.S. Atchison M.A. et al.The lost polyp: a guide to retrieval during colonoscopy.Int J Colorectal Dis. 1988; 3: 229-231Crossref PubMed Scopus (20) Google Scholar Large polyps would often get impacted while ensnared at the rectal sphincter, resulting in inadvertent tearing or transection. Finally, it was tedious work trying to individually handle each piece of a large polyp, and suctioning larger pieces often resulted in “red out” and total loss of visualization. And so we frequently had to repeatedly intubate the colon. All of this provided encouragement for the development of the retrieval net. But the question was not necessarily whether the concept would work, but more so how we would make it work. Fishing nets have a big handle, but believe it or not, re-creating that endoscopically was a challenge, and it remained so for quite a while. I had an image in my head of what the retrieval net would look like and how it might work, but I really did not have any expertise to figure out how to manufacture it. PG: So the idea was there, but obviously it seems that there is more to innovation than just the idea. BR: It took a while to figure out the manufacturing. At the time a buddy of mine was a urologist who had several medical inventions that he had patented. I asked him who I might speak with, and he gave me the name of a gentleman named Marlin E. Younker, who owned a company that made endoscopic accessories (Fig. 2). So I called him and described what I had in mind: The device would look like a standard biopsy forceps but with a net inside the catheter sheath rather than a grasper (Fig. 3). He liked the idea and asked me to give him some time and see if he could come up with a prototype.Figure 3Original hand-drawn illustration of the retrieval net concept.View Large Image Figure ViewerDownload Hi-res image Download (PPT) After a few months, he called me and said, “You know, I have tried every piece of material I could find but I cannot get it to stay in the sheath and not break apart or get caught.” He was using a polyethylene material that was soft and malleable, but when you pulled it back and forth in the sheath it would dislodge or tear off the snare rim. Over a year later, I was giving a talk at a national meeting of operating room nurses. I walked through the exhibit area, and sure enough there was Marlin! He had sold his previous company, took a year off, and was getting back into the medical accessory business. These were the early days of laparoscopic cholecystectomy, and the surgeons were looking for a device to grasp the gallbladder and not have it leak as they were taking it out. So I looked at the device: It was a net-like device that could open and close but had a rubber pouch instead of netting material. I told him that was basically what I had wanted to make! So, we went back to the drawing board. We ended up choosing bridal netting. Dean J. Secrest is an innovative research and development guy who worked with Marlin. He bought a variety of netting from a bridal store. But instead of molding or gluing it, he took a snare and fed the wire through the netting and cut it around and tied it on, and it worked! So they made a few prototypes and flew them out to California (Fig. 4). At first we played with grasping marbles. The very next day, I used it on a patient where I took out a polyp and then grasped the pieces out. The retrieval net worked like a charm, and we easily ended up using all the prototypes! From there, we put in a request to the U.S. Food and Drug Administration and got rapid approval. PG: Besides having the idea, how savvy were you in terms of protecting your idea and making sure you received proper credit for your idea? Speaking of which, what did you get in return for your idea? BR: I was very naïve in this area—I was a doctor, not an inventor. I had to rely on Marlin Younker and his team. They applied for the patent on behalf of their company, U.S. Endoscopy Group, Inc (now part of Steris, Mentor, Ohio, USA) (Fig. 5).12Secrest DJ, Younker ME. Retrieval device. U.S. Patent No. 6,814,739. Washington, DC: U.S. Patent and Trademark Office, 2004.Google Scholar Realizing this is not always the case in the business world, I consider myself extremely fortunate all these years that they have always been fair and nice and kept me as part of the team in developing new variations and new models of the retrieval net as well as other retrieval and therapeutic devices (Figs. 6 and 7).Figure 6The current Roth Net. Note the meticulous hand-woven netting around the wire frame.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Figure 7The Roth Net Platinum was the first major redesign of the original Roth Net and features a hexagonal net configuration.View Large Image Figure ViewerDownload Hi-res image Download (PPT) I receive a royalty that is based on sales. U.S. Endoscopy owned the product and so were entitled to the lion’s share for the manufacturing and marketing. Honestly, I really had no idea how to navigate the world of innovation. At first glance, it seems intuitive that the inventor of these devices would get the lion’s share, but when you think about it, your idea is actually a fairly small portion of the overall process and costs of doing business. The company has to take the risk on your idea, spend the money to get the patent, pay the salaries of the workers, and pay the costs for manufacturing, distribution, and advertising. So I felt that they were justifiably entitled to the majority of the money. In my case, U.S. Endoscopy has fortunately always been very kind to me, and so I never had any regrets (Fig. 8). PG: When you invented the retrieval net, did you have to make a separate deal with the University of California? Did UCLA try to claim royalty? BR: Coincidentally and fortunately, I was out in private practice at the time. But you bring up a good point: had I been full time at UCLA, I would have had to potentially give all the royalties to the university. PG: Rumor has it that the Roth Net is still handmade. BR: That is one thing that a lot of people may not know: The retrieval net has for the most part always been handmade. At one point, U.S. Endoscopy tried to automate the production with 1 to 2 machines that cost about $300,000 each, but found that the machine-manufactured nets did not perform as well as the handmade nets, both from a quality and reliability standpoint. They ended up dumping the machines and went back to making the retrieval nets by hand. The nets are still made by hand. There is a U.S. Endoscopy factory in Mentor, Ohio that makes retrieval nets 24 hours a day, split into three 8-hour shifts (Fig. 9). PG: As I understand it, the original net was designed for polyp retrieval and subsequently was adapted for use in foreign body retrieval as well. Can you tell us about how the design of the retrieval net has changed over the years? BR: Shortly after the retrieval net came out and we were routinely using it for polyps, we started also using it for foreign body retrieval. Although it was quite successful, we did find that it required some additional modifications in the net, with a stiffer wire and a hinged rather than oval design so that it retained its shape and pliability in small spaces. We also realized the need to manufacture nets of various sizes to accommodate small and large polyps and objects. We also changed the size of the netting spaces to achieve easier visualization for foreign bodies or polyps. Once we made these modifications, we found that the net was extremely useful for foreign body retrieval, especially small button batteries that kids tended to swallow as well as meat impactions, coins, and other small objects (Fig. 10).13Webb W.A. Management of foreign bodies of the upper gastrointestinal tract: update.Gastrointest Endosc. 1995; 41: 39-51Abstract Full Text Full Text PDF PubMed Scopus (477) Google Scholar In addition to modifications in net design by U.S. Endoscopy as well as by other medical accessory companies both in the United States and around the world, there have been numerous retrieval devices that have been introduced to our armamentarium. These include specific devices for removal of very sharp, odd-shaped, smooth-surfaced, tiny objects as well as food impactions. The current modern-day endoscopy unit is n