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Christopher J Gostout

Publications and source records attributed to Christopher J Gostout.

At least 19 recordsLinked to original sources
PubMed2007

Endoscopic full-thickness closure of large gastric perforations by use of tissue anchors.

BACKGROUND: A flexible needle-catheter tissue-anchoring device was developed to accomplish full-thickness tissue apposition of the GI wall. The aim of this study was to identify the performance of this device for repair of large iatrogenic gastric perforations in a porcine model. OBJECTIVES: Six pigs. DESIGN: Short-term survival animal study. SETTINGS: Pigs were studied while they were under general anesthesia. Device performance in differing gastric locations and wall thicknesses was assessed by 2 perforations more than 2 cm in size created for each pig along the greater curvature and the anterior wall. INTERVENTIONS: Each perforation was closed by parallel placement of tissue anchor sets sequentially along the length of the perforation. MAIN OUTCOME MEASUREMENTS: One week follow-up endoscopy and necropsy were performed. RESULTS: Twelve perforations were closed with the 48 tissue anchor sets. All animals survived for 1 week without clinical complications. Follow-up endoscopy and necropsy revealed that all tissue anchors remained with firmly held sutures and sealed perforations. CONCLUSIONS: Full-thickness closure with a new tissue-anchoring device simply and successfully repaired large iatrogenic gastric perforations.

Animals↗
PubMed2006

A novel endoscopic approach to brachytherapy in the management of Hilar cholangiocarcinoma.

OBJECTIVES: Traditionally, biliary brachytherapy sources are placed percutaneously via transhepatic drains or endoscopically via nasobiliary tubes (NBT). Another ERCP is needed for stent replacement after NBT removal. The aim of this study was to determine the feasibility and safety of endoscopic transpapillary insertion of irradiation sources through 10-Fr stents. METHODS: Medical records of Mayo Clinic Rochester patients undergoing biliary brachytherapy for hilar cholangiocarcinoma (CCA) were reviewed. Patients were part of a treatment protocol with curative intent including external beam radiation therapy (4,500 cGy), radiation sensitization (5-FU), and low dose rate (LDR) brachytherapy (<3,000 cGy) followed by liver transplantation. The 10-Fr biliary stent placed across the malignant biliary stricture was directly cannulated using a radiopaque (192)Ir embedded ribbon within a 300-cm long, 5.1-Fr plastic sheath. After withdrawal of the endoscope, the external end of the brachytherapy catheter was rerouted transnasally and secured. Each patient was hospitalized in a shielded room up to 24 h after which the brachytherapy catheter was removed by hand. RESULTS: Between 1999 and 2004, 32 patients underwent biliary brachytherapy via endoscopically placed 10-Fr plastic stents (mean age 50.6 yr, 69% PSC, bilateral brachytherapy catheters 28.1%). The technical complication observed was immediate brachytherapy catheter displacement (7 of 32, 22%) managed by prompt brachytherapy catheter repositioning. CONCLUSION: LDR biliary brachytherapy administration via endoscopically placed biliary stents is technically feasible and appears reasonably safe in select patients with unresectable perihilar CCA. Unlike NBTs, stents can potentially be placed in bilateral ductal systems to accommodate dual brachytherapy catheters when indicated.

Bile Duct Neoplasms↗
PubMed2006

The endoscopic transilluminator: an endoscopic device for identification of the proximal jejunum for transgastric endoscopic gastrojejunostomy.

BACKGROUND: Localization of the proximal jejunum is important for creation of gastrojejunal anastomosis to palliate gastric outlet obstruction or for treatment of obesity with gastric bypass. OBJECTIVE: To facilitate identification of the proximal jejunum during transgastric endoscopic gastrojejunostomy with the use of an endoscopic transilluminator (ET). DESIGN AND SETTING: Acute experiments in a live porcine model. INTERVENTIONS: The ET is a 3500-mm long, 6F radio-opaque tube with a fiberoptic core that lights up at its distal end. When situated in the intestinal lumen, it transilluminates the bowel wall. With the animal under general anesthesia with endotracheal intubation, a colonoscope was advanced to the proximal jejunum. A plastic tube (3500-mm long, 3.5 mm in diameter) was passed through the biopsy channel and placed into the small bowel. The colonoscope was withdrawn, leaving the tube in place. The ET was introduced into the jejunum through the tube. A gastric wall incision was made and the endoscope was advanced to the peritoneal cavity. The transilluminated loop of the proximal jejunum was identified and gastrojejunal anastomosis was made by use of a previously reported endoscopic technique. MAIN OUTCOME MEASUREMENTS: Identification of the proximal jejunum. RESULTS: Eleven pigs (average weight 55 kg) had ET placement. In all of the pigs, placement of the ET was performed easily to the proximal small bowel, and the proximal jejunum was successfully localized by either direct visualization of the transilluminated loop only or with the aid of fluoroscopy. The tip of the ET was usually located about 50 to 70 cm distal to the ligament of Treitz. There were no complications related to the use of ET. LIMITATIONS: The device has not yet been evaluated in humans. CONCLUSIONS: The ET is a safe instrument and can be used to identify the proximal jejunum to facilitate endoscopic gastrojejunostomy.

Animals↗
PubMed2006

Immediate endoscopic closure of colon perforation by using a prototype endoscopic suturing device: feasibility and outcome in a porcine model (with video).

BACKGROUND: Perforation is an uncommon but potentially devastating complication of colonoscopy. Surgical closure is the standard of care. Immediate endoluminal closure of a perforation would avoid the morbidity and mortality associated with general anesthesia, laparotomy, and surgical repair. OBJECTIVES: To evaluate the feasibility and safety of full-thickness endoscopic closure of colonic perforations with a prototype endoscopic suturing device, the Eagle Claw, in a porcine model. DESIGN: Endoscopic animal experimental study of closure of colon perforation by using a porcine model. SUBJECTS: Ten pigs were included in the study. INTERVENTIONS: The Eagle Claw was used to close small perforations (1.5 to 2 cm) of the colon created by needle-knife with the animal under general anesthesia by using the endoluminal route. All animals received intravenous antibiotics and were allowed to eat after 24 hours. MAIN OUTCOME MEASUREMENTS: The animals were monitored daily for signs of sepsis and peritonitis. On day 7, they were euthanized. The peritoneal cavity was examined for fecal peritonitis, and the colon perforation site was checked for wound dehiscence and pericolic abscess formation. RESULTS: Endoscopic closure of the colon perforation was successful in 7 animals, and they recovered well without any sepsis or peritonitis. Necropsy did not reveal fecal peritonitis or pericolonic abscess formation at the site of perforation, and the perforation healed well. Closure was successful in 1 animal, but necropsy revealed dehiscence of the colon perforation site. Endoscopic closure was unsuccessful in 2 animals, and these were euthanized immediately. CONCLUSIONS: Closure of acute perforation of the colon is feasible with the Eagle Claw endoscopic suturing device in a porcine model.

Animals↗
PubMed2006

Pilot study of the porcine uterine horn as an in vivo appendicitis model for development of endoscopic transgastric appendectomy.

BACKGROUND: Iatrogenic inflammation of the porcine uterine horn may serve as an in vivo appendicitis model for the development of endoscopic transgastric appendectomy. OBJECTIVE: Five female pigs. STUDY DESIGN: Animal study. SETTINGS: General anesthesia. MAIN OUTCOME MEASUREMENTS: Anatomical appearance and technical feasibility. INTERVENTIONS: Three pigs were used to identify an injectable material that would inflame the uterine horn, and 2 pigs were used for a pilot appendectomy. Three types of materials were individually injected into the bilateral uterine horns, and the ideal material to inflame the uterine horn was injected into the right uterine horn for the last 2 pigs. After 24 hours, the injected uterine horns of the first 3 pigs were assessed and a pilot appendectomy was performed in the last 2 pigs. RESULTS: Ethanolamine oleate (EO) injected uterine horns demonstrated similarities to the inflamed human appendix. Simulations of the appendectomy were successfully performed by using the EO model. LIMITATIONS: Suboptimal existing tools. CONCLUSIONS: This preliminary study demonstrated the technical feasibility to create a model for acute appendicitis by using the porcine uterine horn and transgastric appendectomy.

Animals↗
PubMed2006

Tissue anchors for transmural gut-wall apposition.

BACKGROUND: With the development of NOTES (natural orifice transluminal endoscopic surgery) and efforts to advance gastric reduction surgery, alternatives for robust tissue apposition apart from suturing and current mucosal clipping devices may be valuable. OBJECTIVES: We attempted to identify functional tissue anchors that could be deployed endoscopically, with the potential to provide transmural tissue apposition. DESIGN: Short-term animal-survival study. PATIENTS: Domestic pigs, under general anesthesia, underwent open laparotomy, gastrotomy, and manual placement of prototype tissue anchors. INTERVENTIONS: Four tissue-anchor designs were evaluated (T bar, T bar with mesh bolster, star, basket). Full-thickness gastric plications were manually created in the body and the antrum via laparotomy and were secured with sets of paired anchors, also placed manually via a gastrotomy. In 1 test animal, a pilot gastric reduction was created by forming 2 rows of 4 anchor sets on the anterior and posterior walls to create a tubelike gastric lumen. MAIN OUTCOME MEASUREMENTS: Follow-up endoscopy was performed at 2, 4, and 9 weeks to visually assess the intraluminal appearance of the plications, followed by necropsy and histologic study. RESULTS: There was an overall attrition of the number of anchor sets. At 2 weeks, the T-bar anchors were first to disappear, and the mesh and the star designs began to pull through the gastric folds. At 4 weeks, there was flattening of the plications that involved 6 pairs of mesh anchors. By 9 weeks, 3 pairs of mesh anchors were lost and 3 pairs were associated with flattened folds. At the time of euthanasia, at 4 or 9 weeks, the number of retained anchors associated with intact plications for each group were as follows: T bar, 6 of 9 pairs (67%); mesh, 12 of 18 pairs (67%); basket, 14 of 18 pairs (78%); and star, 2 of 9 pairs (22%). There were no gastric adhesions and no evidence for any inflammatory changes surrounding the stomachs. The tallest plications involved the basket anchors. The basket-anchored plications contained apposed muscularis propria, with serosal fusion evident. The folds from the other anchor types were formed of mucosa and submucosa with or without superficial muscularis propria. CONCLUSIONS: The results of this experience are encouraging. The basket tissue anchors appear most promising. These findings suggest that further development of tissue anchors deployed via flexible catheter-based devices may have clinical value for transmural tissue apposition.

Animals↗
PubMed2005

Prospective, randomized, controlled trial of prophylactic pancreatic stent placement for endoscopic snare excision of the duodenal ampulla.

BACKGROUND: Tumors that arise in the region of the major duodenal papilla account for 5% of GI neoplasms and 36% of resectable pancreaticoduodenal tumors. There is limited published literature that addresses the safety of endoscopic excision of the papilla. Although there is consensus about prophylactic pancreatic-duct stent placement, there is little supporting prospective data. The aim of this randomized, controlled trial was to compare the rates of postsnare ampullectomy pancreatitis in patients who did/did not receive prophylactic pancreatic-duct stent placement. METHODS: Consecutive patients who were to undergo en bloc snare ampullectomy were randomized to placement of pancreatic-duct stent after ampullectomy or to no stent placement. RESULTS: In total, 19 patients were enrolled, and 10 received pancreatic stents. Postprocedure pancreatitis occurred in 3 patients in the 24 hours after endoscopy, all cases occurred in the unstented group, 33% vs. 0% (stented group), p = 0.02. Median peak amylase level was 3692 U/L (range 1819-4700 U/L) and median peak lipase level was 11450 U/L (range 5900-17,000 U/L). All 3 patients were hospitalized for a median of 2 days (range 1-6), and all made a complete recovery. CONCLUSIONS: Our findings suggest that a protective effect is conferred by pancreatic stent placement in reducing postampullectomy pancreatitis. Future large-scale studies are required to confirm this benefit.

Adult↗
PubMed2005

Endoscopic treatments for obesity: past, present and future.

Obesity is recognized as a serious, chronic illness affecting all ages. The cause for obesity is multi-factorial, which makes successful management complex and challenging. Meaningful weight loss is frequently difficult to achieve, particularly when the goal is not merely to lose weight but to maintain this loss. The efficacy of future endoscopic approaches needs to be validated through well-designed controlled studies, and verification of safety is essential. Endoluminal therapies must have a sound physiologic basis for their development. The availability of specialized radionuclide imaging of gastric capacity and accommodation provide a useful tool in constructing interventions. Endotherapy is likely best suited for nonmorbid obese individuals with BMI ranging from 30 to 39 or as a budge to bariatric surgery. This specific BMI range has been targeted by the National Institutes of Health for emerging technologies. Presurgical weight loss to reduce surgical risk is another potential target group. Regardless of which endoscopic methods prevail, patients will continue to require a comprehensive, multi-modality management approach to this complex disease.

Bariatrics↗
PubMed2005

Peroral transgastric endoscopic ligation of fallopian tubes with long-term survival in a porcine model.

BACKGROUND: We have previously reported the feasibility and safety of the peroral transgastric endoscopic approach for diagnostic peritoneoscopy, liver biopsy, and gastrojejunostomy with long-term survival in a porcine model. This approach eliminates incisions of the abdominal wall, providing a less invasive alternative to diagnostic and therapeutic laparoscopy. We now report successful performance of peroral endoscopic transgastric ligation of Fallopian tubes with long-term survival in a porcine model. METHODS: Six female 50-kg pigs had general anesthesia and irrigation of the stomach with an antibiotic solution. Gastric puncture was performed with needleknife electrocautery followed by balloon dilatation of the tract with 20-mm TTS dilating balloon (Microvasive). A standard upper endoscope that underwent high-level disinfection and gas sterilzation was advanced into the peritoneal cavity through a sterile overtube. Both Fallopian tubes were identified and one was ligated using Olympus Endoloops. The other patent tube served as a control. Tubal patency was evaluated by hysterosalpingogram before and after ligation. After a follow-up period of 2-3 weeks, the pigs were sacrificed for postmortem examination. RESULTS: The Fallopian tubes were easily accessed, identified and ligated in all 6 pigs. In each pig, fluoroscopy confirmed complete obstruction of the ligated tube with preserved patency of the other tube. All pigs survived well and ate heartily without any ill-effects. Postmortem examination did not reveal any peritonitis or intra-abdominal adhesions. The Endoloops were in place with complete obstruction of the ligated tubes and patency of the controls. Histopathologic examination of the tubes showed chronic inflammatory infiltrates without abscesses. CONCLUSIONS: The peroral endoscopic transgastric approach to ligation of the Fallopian tubes with long-term survival is technically feasible and safe in a porcine model. The endoscopic transgastric approach to the peritoneal cavity has potential for a wide array of diagnostic and therapeutic procedures.

Animals↗
PubMed2005

Endoscopic suturing without extracorporeal knots: a laboratory study.

BACKGROUND: To eliminate cumbersome extracorporeal knotting, we designed a new endoscopic suturing device, the Eagle Claw V. The efficacy of the new device was tested on the Erlangen model and was compared with the initial extracorporeal knotting version (Eagle Claw II). METHODS: Segments of porcine splenic arteries were placed on the mucosal surface of the anterior wall of a pig stomach. The two ends of the artery were brought out through the gastric wall and were connected to a two-channel manometer. The Eagle Claw V has a curved needle with a detachable tip. After puncturing the tissue, the needle tip was engaged into a catching cartridge, where the suture had been embedded in a tightening mechanism. The suture could be tightened by simply pulling the end. The Eagle Claw V was used to plicate the splenic arteries mounted on the stomach. Suturing was considered secure if the suture could withstand endoluminal pressure greater than 200 mm Hg that lasted at least 10 seconds. RESULTS: Eleven of 15 stitches (73.3%) gained secure plication of the vessels. The suturing time (mean +/- standard deviation 2.93 +/- 0.80 minutes) was significantly faster than that of the Eagle Claw II (9.38 +/- 1.51 minutes). The device consistently achieved penetration of the muscular layer, and 4 of 15 sutures included the serosa. The 4 failures were because of suture breakage in two, thread entanglement in one, and cartridge dislodgement in one. CONCLUSIONS: The present prototype represents significant improvements in the ease of operation and the security of the suture, bringing the technique closer to clinical use for a variety of applications.

Animals↗
PubMed2005

Eagle Claw II: A novel endosuture device that uses a curved needle for major arterial bleeding: a bench study.

BACKGROUND: Control of bleeding from major arteries in the upper-GI tract remains difficult with currently available endoscopic devices. We designed an endosuture device that uses a curved needle and extracorporeal knotting, and assessed the device in stopping arterial bleeding in a bench model. METHODS: Harvested porcine splenic arteries (2-mm diameter) were tunneled submucosally in pig stomach with the open end protruding into an artificially created mucosal defect. The outer end of the vessel was connected to a pulsatile pump, and red ink was infused at a pressure of about 100 mm Hg. The stomach was installed on an Erlangen endo-training model. The suturing device (Eagle Claw II), mounted outside an endoscope, has an eyed, curved needle that carries a 3-0 nylon thread. After puncture, the thread was retrieved by using a hook. Three-throw square knots were tied at the thread extracorporeally and were pushed into place by using a knotting cap. The criteria of successful plication was defined as hemostasis after knotting, no leakage at pressures of >200 mm Hg, and the vessel was completely encircled by the suture. RESULTS: A total of 25 sutures were made with the mean time of 9.38 minutes (standard deviation 1.51). Control of the bleeding was obtained with 17 sutures (68%). The causes for failure were the following: a suture was too shallow (4), a loose knot (2), incorrect suture position (1), and stomach-wall edema (1). CONCLUSIONS: Control of bleeding from large arteries by using endoscopic suturing is possible. Continued refinements of the device are required.

Animals↗
PubMed2005

Endoscopic gastrojejunostomy with survival in a porcine model.

BACKGROUND: We have previously reported the feasibility and the safety of an endoscopic transgastric approach to the peritoneal cavity in a porcine model. We now report successful performance of endoscopic gastrojejunostomy with survival. METHODS: All procedures were performed on 50-kg pigs, with the pigs under general anesthesia, in aseptic conditions with sterilized endoscopes and accessories. The stomach was irrigated with antibiotic solution, and a gastric incision was performed with a needle-knife and a sphincterotome. A standard upper endoscope was advanced through a sterile overtube into the peritoneal cavity. A loop of jejunum was identified, was retracted into the stomach, and was secured with sutures while using a prototype endoscopic suturing device. An incision was made into the jejunal loop with a needle-knife, and the filet-opened ends of the jejunal wall were secured to the gastric wall with a second line of sutures, completing the gastrojejunostomy. OBSERVATIONS: Two pigs survived for 2 weeks. Endoscopy and a radiographic contrast study performed after gastrojejunostomy revealed a patent anastomosis with normal-appearing gastric and jejunal mucosa. Postmortem examination demonstrated a well-healed anastomosis without infection or adhesions. CONCLUSIONS: The endoscopic transgastric approach to create a gastrojejunostomy is technically feasible and can be performed, with survival, in a porcine model.

Animals↗
PubMed2005

A randomized trial of endoscopic biliary sphincterotomy using pure-cut versus combined cut and coagulation waveforms.

BACKGROUND & AIMS: Endoscopic biliary sphincterotomy has complication rates of 5%-12%. The output from the electrosurgical generator may influence the degree of coagulation and the rapidity of the incision, and thus rates of pancreatitis, hemorrhage, and perforation. Some modern generators incorporate feedback control to standardize output and automate the alternating cut and coagulation modes. Our aim was to compare 2 feedback-controlled generators, one with constant pure cutting-type output and the other with an alternating cut and coagulation mode. METHODS: In this multicenter randomized study, 133 patients were assigned to the alternating cut/coag output and 134 patients were assigned to constant pure-cut output. Patients were stratified by their risk for pancreatitis. RESULTS: The overall pancreatitis rate was 1.5%, including 3 patients in the cut/coag group and 1 patient in the pure-cut group (P>.05). There were 11 poorly controlled (zipper) incisions in the pure-cut group and none in the cut/coag group (P=.02). The incision was completed in all patients without stalling. Immediate hemorrhage occurred in 35 pure-cut patients and 8 cut/coag patients output (P=.002). There were no episodes of clinically significant bleeding, delayed bleeding, or perforation. CONCLUSIONS: Biliary sphincterotomy using feedback-controlled generators results in dependable progression of incision with a low pancreatitis rate. Control of the incision is improved subjectively with the cut/coagulation output, but this did not translate into a difference in clinically significant complications.

Adult↗
PubMed2005

Direct percutaneous endoscopic jejunostomy: outcomes in 307 consecutive attempts.

BACKGROUND: Clinical utilization of direct percutaneous endoscopic jejunostomy (DPEJ) is increasing. However, little data exist regarding important clinical outcomes with DPEJ. OBJECTIVE: To describe the indications, success, and complications of DPEJ in a large cohort of >300 consecutive attempted DPEJ cases at our institution. METHODS: Institutional databases identified 316 consecutive attempted DPEJ placements between January 1996 and August 2004. The medical records of consenting patients were abstracted for demographics, indication, success, complications, and follow-up. A scheme for classifying complication severity was designed. RESULTS: Three hundred and seven attempts at DPEJ were made on 286 patients. Of these, 209 succeeded (68%). The most common indications for DPEJ included resectable distal esophageal cancer, other malignancies causing obstruction, gastroparesis, prior esophageal or gastric resection, and high aspiration risk. Overall, 81 adverse events (AEs) were associated with DPEJ placement or removal in 69 (22.5%) cases. There were 14 serious AEs, 20 moderate AEs, and 47 mild AEs. Serious AEs included 7 bowel perforations, 3 jejunal volvuli, 3 major bleeds, and 1 aspiration. The only death was due to profound jejunal mesenteric bleeding after an unsuccessful trocar pass. Moderate AEs included 9 chronic enterocutaneous fistulae. Many of the 47 mild AEs were site infections requiring oral antibiotics (23) or persistent site pain (14). CONCLUSIONS: DPEJ was associated with a moderate or severe complication in approximately 10% of cases. While DPEJ is a useful technique to gain enteral access that obviates the need for surgery and is more reliable than percutaneous gastrostomy with jejunal extension, patients and physicians should be aware of the risks involved.

Adult↗
PubMed2004

Complications of temporary pancreatic stent insertion for pancreaticojejunal anastomosis during pancreaticoduodenectomy.

BACKGROUND: Morbidity associated with pancreaticoduodenectomy usually results from complications associated with the pancreaticojejunal anastomosis, in particular, a pancreatic leak. Four patients with retained transanastomotic pancreatic stent-induced complications after pancreaticduodenectomy were identified. METHODS: Medical records for the 4 patients were reviewed, and telephone interviews were conducted. OBSERVATIONS: Each patient underwent pancreaticoduodenectomy for a peripapillary tumor with creation of a pancreaticojejunal anastomosis by using an internal 8F Silastic stent. Subsequent evaluation for steatorrhea (n=3) or recurrent pancreatitis (n=1) led to discovery of a retained pancreatic stent. In one patient, the stent was incidentally discovered. Steatorrhea significantly improved (n=1) or resolved (n=2) after stent removal. The patient with pancreatitis has not experienced another episode. CONCLUSIONS: The possibility of a retained stent should be considered in patients presenting with steatorrhea or pancreatitis after pancreaticoduodenectomy.

Adult↗
PubMed2004

Widespread EMR: a new technique for removal of large areas of mucosa.

BACKGROUND: Widespread EMR is a novel technique for resection of large areas of mucosa as a single bloc. Large lesion size (>2 cm) is a recognized limitation of current EMR techniques. This study assessed the technical feasibility, efficacy, and safety of widespread EMR in a porcine model. METHODS: Widespread EMR was performed in 6 pigs. A submucosal fluid cushion was created in the distal esophagus by using a 0.83% solution of hydroxypropyl methylcellulose. A mucosal strip 5 cm in length and including at least 50% of the luminal circumference was marginated by using a prototype cutting device. The proximal end of the mucosa was stripped from the submucosa by using a grasping forceps. The distal end was snare resected. Resected tissue was assessed histologically. Endoscopy was repeated at weeks 1 and 6. At week 6, a second widespread EMR of the mucosa on the wall opposite the initial resection was attempted to create a full circumferential resection. RESULTS: Widespread EMR was completed in all animals. The esophagus was denuded of mucosa in 5-cm lengths that included 50% of the circumference of the lumen. No procedure-related complication was observed. Histologic assessment demonstrated that the resection specimen included mucosa and submucosa but not muscularis propria. Endoscopy at 1 week revealed mucosal regrowth in two animals and ulceration in 4. At week 6, regrowth of mucosa was noted in all animals. The second wide EMR proved to be technically difficult and was associated with perforation, peri-esophageal abscess, and stricture formation. CONCLUSIONS: Wide EMR appears to be technically feasible for removal of large areas of mucosa. Mucosal strips 5 cm long that included over 50% of the luminal circumference were resected safely. Resection was followed by complete regrowth of the mucosa. However, a second wide EMR to create a circumferential resection proved to be technically difficult and unsafe.

Animals↗