Feasibility of pure EFTR using an innovative new endoscopic suturing device: the Double-arm-bar Suturing System (with video)

Endoscopic ligation technique for refractory gastrotracheal fistula

Endoscopic therapy has recently undergone remarkable progress, including the use of suturing procedures within the gastrointestinal tract using flexible endoscopes. However, existing suturing techniques primarily involve closure using instruments or continuous sutures using an endoscopic needle holder, leaving a gap in nodal suturing methods with extracorporeal ligation. This paper introduces a novel approach, the endoscopic ligation technique, wherein a flexible endoscope is utilized for nodal suturing through extracorporeal ligation.

Novel through-the-scope twin clip for the closure of GI wounds: the first experimental survival study in pigs (with videos)

BACKGROUND AND AIMS

We developed a through-the-scope twin clip (TTS-TC) for closing GI wounds. The objective of this study was to evaluate the efficacy and safety of the TTS-TC in GI wound closure.

METHODS

GI nonperforating and perforating wounds (≥2.5 cm) were created in live pigs. TTS-TCs were used to convert the large wounds into small wounds. The remaining small wounds were closed using conventional through-the-scope clips (TTSCs). The follow-up period was 1 month. Location and size of the wound, time of wound closure, intraoperative and postoperative adverse events, and conditions of wound healing were investigated.

RESULTS

Thirteen wounds were created in 5 live pigs, including 2 gastric nonperforating and 3 perforating wounds and 5 large intestinal nonperforating and 3 perforating wounds. The mean long and short diameters of the wounds were 4.1 (± .9) cm and 3.4 (± .7) cm, respectively. All wounds were successfully closed using the TTS-TCs combined with TTSCs. The total mean time for wound closure was 9.2 (± 5.3) minutes, and the mean time for using the TTS-TCs was 3.9 (± 4.7) minutes. During the 1-month follow-up period, no bleeding, perforation, or death occurred; all wounds healed with scar formation; and all TTS-TCs detached spontaneously.

CONCLUSIONS

The TTS-TC was successfully used to close large-sized GI wounds. The TTS-TC is a promising tool for large-size wound closure under flexible endoscopy.

Peroral traction-assisted natural orifice trans-anal flexible endoscopic rectosigmoidectomy followed by intracorporeal colorectal anastomosis in a live porcine model

BACKGROUND

Compared to traditional open surgery, laparoscopic surgery has become a standard approach for colorectal cancer due to its great superiorities including less postoperative pain, a shorter hospital stay, and better quality of life. In 2007, Whiteford et al reported the first natural orifice trans-anal endoscopic surgery (NOTES) sigmoidectomy using transanal endoscopic microsurgery. To date, all cases of NOTES colorectal resection have included a hybrid laparoscopic approach with the use of established rigid platforms.

AIM

To introduce a novel technique of peroral external traction-assisted transanal NOTES rectosigmoidectomy followed by intracorporeal colorectal end-to-end anastomosis by using only currently available and flexible endoscopic instrumentation in a live porcine model.

METHODS

Three female pigs weighing 25-30 kg underwent NOTES rectosigmoid resection. After preoperative work-up and bowel preparation, general anesthesia combined with endotracheal intubation was achieved. One dual-channel therapeutic endoscope was used. Carbon dioxide insufflation was performed during the operation. The procedure of trans-anal NOTES rectosigmoidectomy included the following eight steps: (1) The rectosigmoid colon was tattooed with India ink by submucosal injection; (2) Creation of gastrostomy by directed submucosal tunneling; (3) Peroral external traction using endoloop ligation; (4) Creation of rectostomy on the anterior rectal wall by directed 3 cm submucosal tunneling; (5) Peroral external traction-assisted dissection of the left side of the colon; (6) Trans-anal rectosigmoid specimen transection, where an anvil was inserted into the proximal segment after purse-string suturing; (7) Intracorporeal colorectal end-to-end anastomosis using a circular stapler by a single stapling technique; and (8) Closure of gastrostomy using endoscopic clips. All animals were euthanized immediately after the procedure, abdominal exploration was performed, and the air-under-water leak test was carried out.

RESULTS

The procedure was completed in all three animals, with the operation time ranging from 193 min to 259 min. Neither major intraoperative complications nor hemodynamic instability occurred during the operation. The length of the resected specimen ranged from 7 cm to 13 cm. With the assistance of a trans-umbilical rigid grasper, intracorporeal colorectal, tension-free, end-to-end anastomosis was achieved in the three animals.

CONCLUSION

Peroral traction-assisted transanal NOTES rectosigmoidectomy followed by intracorporeal colorectal end-to-end anastomosis is technically feasible and reproducible in an animal model and is worthy of further improvements.

Endoscopic full-thickness resection using an endoluminal-suturing device: a proof-of-concept study

Background and study aims  Endoscopic full-thickness resection (EFTR) is used to achieve R0 resection in difficult situations and as a way to overcome the limitations of endoscopic submucosal dissection. Multiple techniques have been described but adequate tools are still under evaluation. In this study, we evaluated the safety and feasibility of non-exposed endoscopic full-thickness resection using a novel endoscopic suturing device. Materials and methods  Full-thickness resections of gastric predetermined lesions were performed on five pigs using the Endomina platform. After creating virtual lesion > 20 mm, sutures were placed around it using this triangulation platform. After tightening the knots, the bulging lesion, internalized into the gastric lumen, was cut with a needle knife. Results  R0 resections of large lesions (42 to 60 mm) were achieved in all cases. One perforation occurred and prompted us to improve the procedure by shortening the sutures for more maneuverability and reinforcing the suture line before section. Procedure duration dropped by 50 % between the first case and the fourth case. Histological analysis confirmed successful full-thickness resection of all resected specimens. Conclusion  EFTR using this triangulation platform seems feasible for lesions > 20 mm. Additional possible improvements were identified to simplify the procedure before moving to human trials.

Endoscopic full thickness resection versus submucosal tunneling endoscopic resection for removal of submucosal tumors: a review article

Submucosal tumors (SMT) are protuberant lesions with intact mucosa that have a wide differential. These lesions may be removed by standard polypectomy, endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), or surgically. However, in lesions that arise from the muscularis propria, full thickness resection is recommended. This can be completed using either endoscopic full thickness resection (EFTR) or submucosal tunneling endoscopic resection (STER). EFTR can be accomplished by completing a full thickness resection followed by defect closure or by securing gastrointestinal wall patency before resection. STER is an option that first creates a mucosal dissection proximal to the lesion to allow a submucosal tunnel to be created. Using this tunnel, the lesion may be resected. When comparing STER to EFTR, there was no significant difference when evaluating tumor size, operation time, rate of complications, or en bloc resection rate. However, suture time, amount of clips used, and overall hospital stay were decreased in STER. With these differences, EFTR may be more efficacious in certain parts of the gastrointestinal tract where a submucosal tunnel is harder to accomplish.

Feasibility and safety of third-space endoscopic full-thickness resection in ex vivo and in vivo porcine models

Background and study aims  Endoscopic full-thickness resection (EFTR) involves several technical issues that need to be addressed. We devised a novel technique termed third-space EFTR and investigated its feasibility and safety in animal models. Methods  Third-space EFTR was performed in three isolated porcine stomachs (ex vivo) and four live pigs (in vivo, 1-week survival). The technique involved a circumferential mucosal incision, submucosal tunnelling on the proximal side, endoscopic suturing of the surrounding mucosa, a circumferential seromuscular incision in the submucosal tunnel, transoral retrieval and entry site closure of the tunnel. The technical outcomes were investigated. Results  In the ex vivo study, the procedure was successfully completed with R0 resection. In the in vivo study, the procedure was completed in all pigs; however, R0 resection failed in one pig owing to snaring resection. All pigs survived without severe adverse events. Conclusions  Our findings indicate that third-space EFTR is feasible and safe. This technique may be useful as a minimally invasive endoscopic option for reliable treatment of small gastric submucosal tumours.

Current status and future perspectives of endoscopic full-thickness resection

Flexible endoscopy has developed from a diagnostic tool for tissue biopsy sampling to a treatment tool for endoscopic resection of neoplasms in the digestive tract. In the near future, one of the advanced endoscopic techniques, endoscopic full-thickness resection (EFTR), is expected to be a feasible endoscopic procedure. In the present review, systematic review of conventional exposed EFTR was carried out. Search queries were (endoscopic full-thickness resection or EFTR) (over-the-scope clip or OTSC) (Overstitch System) from 2015 to 2017. Four retrospective, single-center studies with regard to conventional EFTR were identified. With regard to indication for conventional exposed EFTR, gastrointestinal stromal tumor was a good indication for EFTR. Mean tumor size of all four studies was 20.71 mm. In two studies, endoclips were used to close the resected opening without any complications, but the other two studies reported complications such as delayed perforation even using OTSC. Procedure times were reported from a minimum of 40 min to a maximum of 105 min. We also refer to introduction of a newly developed procedure of EFTR (non-exposed EFTR), and development of a new suturing device in Japan.

Endoscopic closure after intraluminal surgery

Endoscopic submucosal dissection is established as a curative endoscopic method for gastrointestinal epithelial neoplasms with a high possibility of complete en bloc resection; however, postoperative adverse events of bleeding and delayed perforation remain. To prevent or minimize them, several techniques for endoscopic mucosal closure have been introduced, such as using endoscopic clips, combined use of hemoclips and supplement devices, and specially designed endoscopic suturing devices. Furthermore, endoscopic full-thickness suturing technique for gastrointestinal wall defect has been developed based on the concept in natural orifice transluminal endoscopic surgery and endoscopic full-thickness resection. Several closure techniques, including over-the-scope clip, threaded bars inserted in a hollow needle, stitches or staplers, and a curved needle and thread are reported. Secure closure of the iatrogenic defect may further expand the range of therapeutic endoscopy. Accumulation of evidence for the efficacy of endoscopic closure and establishment of these techniques are desired.

Current Status of Exposed Endoscopic Full-Thickness Resection and Further Development of Non-Exposed Endoscopic Full-Thickness Resection

Endoscopic full-thickness resection (EFTR) is a procedure that makes it possible to access the lesions that are on the wall of the digestive tract via the shortest distance through the mouth. Because of the ultra-minimal invasive nature of the treatment, pure EFTR is a highly promising surgical procedure that allows the radical excision of full-thickness layers of digestive tract tumors using only a flexible endoscope. There are 2 types of EFTR methods: exposed and non-exposed. Considering the risks of contracting infection and intraperitoneal dissemination of tumor cells, non-exposed EFTR is an ideal method. However, a number of issues remain unresolved, including the method for performing a full-thickness suture under endoscopic view and the challenge of securing the operating field in the case of gastrointestinal tract collapse. Moreover, advances in the development of equipment such as full-thickness suturing devices would be helpful to make this therapeutic procedure the most minimally invasive endoscopic surgery ever.

Recent Trends in Endoscopic Bariatric Therapies

Obesity and its associated metabolic diseases including diabetes mellitus are severe medical problems that are increasing in prevalence worldwide and result in significant healthcare expenses. While behavioral and pharmacological treatment approaches are partly effective in the short term, their effects are not long-lasting. Although previous studies have described bariatric surgery as the most effective treatment for obesity, it is associated with morbidity, mortality, and economic burden. Endoluminal interventions performed entirely using gastrointestinal flexible endoscopy offer alternative approaches to the treatment of obesity that are safer and more cost-effective than current surgical approaches. The use of endoluminal techniques in the field of metabolic obesity disease has diverse promising applications including endoscopic gastroplasty, intragastric balloon, endoluminal malabsorptive bariatric procedures, and gastric electrical stimulation (GES) for the modulation of gastric emptying. This review discusses recent trends and roles in endoscopic bariatric therapies using the currently available endoluminal and transgastric technologies.

New devices and techniques for endoscopic closure of gastrointestinal perforations

Gastrointestinal perforations, which need to be managed quickly, are associated with high morbidity and mortality. Treatments used to close these perforations range from surgery to endoscopic therapy. Nowadays, with the development of new devices and techniques, endoscopic therapy is becoming more popular. However, there are different indications and clinical efficacies between different methods, because of the diverse properties of endoscopic devices and techniques. Successful management also depends on other factors, such as the precise location of the perforation, its size and the length of time between the occurrence and diagnosis. In this study, we performed a comprehensive review of various devices and introduced the different techniques that are considered effective to treat gastrointestinal perforations. In addition, we focused on the different methods used to achieve successful closure, based on the literature and our clinical experiences.

Management of a large mucosal defect after duodenal endoscopic resection

Duodenal endoscopic resection is the most difficult type of endoscopic treatment in the gastrointestinal tract (GI) and is technically challenging because of anatomical specificities. In addition to these technical difficulties, this procedure is associated with a significantly higher rate of complication than endoscopic treatment in other parts of the GI tract. Postoperative delayed perforation and bleeding are hazardous complications, and emergency surgical intervention is sometimes required. Therefore, it is urgently necessary to establish a management protocol for preventing serious complications. For instance, the prophylactic closure of large mucosal defects after endoscopic resection may reduce the risk of hazardous complications. However, the size of mucosal defects after endoscopic submucosal dissection (ESD) is relatively large compared with the size after endoscopic mucosal resection, making it impossible to achieve complete closure using only conventional clips. The over-the-scope clip and polyglycolic acid sheets with fibrin gel make it possible to close large mucosal defects after duodenal ESD. In addition to the combination of laparoscopic surgery and endoscopic resection, endoscopic full-thickness resection holds therapeutic potential for difficult duodenal lesions and may overcome the disadvantages of endoscopic resection in the near future. This review aims to summarize the complications and closure techniques of large mucosal defects and to highlight some directions for management after duodenal endoscopic treatment.

Review of Pure Endoscopic Full-Thickness Resection of the Upper Gastrointestinal Tract

Natural-orifice transluminal endoscopic surgery (NOTES) using flexible endoscopy has attracted attention as a minimally invasive surgical method that does not cause an operative wound on the body surface. However, minimizing the number of devices involved in endoscopic, compared to laparoscopic, surgeries has remained a challenge, causing endoscopic surgeries to gradually be phased out of use. If a flexible endoscopic full-thickness suturing device and a counter-traction device were developed to expand the surgical field for gastrointestinal-tract collapse, then endoscopic full-thickness resection using NOTES, which is seen as an extension of endoscopic submucosal dissection for full-thickness excision of tumors involving the gastrointestinal-tract wall, might become an extremely minimally invasive surgical method that could be used to resect only full-thickness lesions approached by the shortest distance via the mouth. It is expected that gastroenterological endoscopists will use this surgery if device development is advanced. This extremely minimally invasive surgery would have an immeasurable impact with regard to mitigating the burden on patients and reducing healthcare costs. Development of a new surgical method using a multipurpose flexible endoscope is therefore considered a socially urgent issue.

Novel NOTES Techniques and Experimental Devices for Endoscopic Full-thickness Resection (EFTR)

Natural orifice transluminal endoscopic surgery (NOTES), in which a flexible endoscope is used to perform operations that have traditionally required laparoscopic surgery, has garnered attention as a minimally invasive surgery that does not leave a surgical wound on the body. Among the various forms of NOTES, endoscopic full-thickness resection (EFTR) is an ultraminimally invasive endoscopic surgery that allows for radical resection, which is an extension of endoscopic submucosal dissection and involves full-thickness excision of a tumor of the gastrointestinal tract wall. With further development of the equipment, including full-thickness suture instruments, nonexposed EFTR could be a feasible surgical procedure.

Endoscopic Submucosal Dissection (ESD) and Related Techniques as Precursors of "New Notes" Resection Methods for Gastric Neoplasms

Endoscopic full-thickness resection for subepithelial tumors is one of the more attractive proposed methods for less-invasive transluminal surgery but remains challenging in terms of safety and feasibility. Currently, laparoscopic endoscopic cooperative surgery is thought to be a more clinically acceptable approach. In targeting cancers, however, more advanced nonexposure techniques are required to avoid the risk of iatrogenic tumor seeding. By combining these techniques with possible regional lymphadenectomy using sentinel node navigation surgery, an ideal minimally invasive, function-preserving gastric resection can be achieved even in possible node-positive cancers. Further development for this type of advanced endoscopic surgery is expected.

Estimation of subepithelial lateral extent in submucosal early gastric cancer: retrospective histological analysis

BACKGROUND

Endoscopic full-thickness resection (EFTR) is expected to make possible minimally invasive local resection of early gastric cancer (EGC). However, no consensus exists regarding how far an optimal safety margin should be set in determining the resection area by endoscopy. We aimed to investigate the optimal lateral margin of EGC which could be a candidate for EFTR by measuring the subepithelial extent (SE) of tumors.

METHODS

In 60 surgically resected submucosal EGCs 4 cm or smaller, 595 prepared slides which showed lateral tumor borders both on the epithelial surface and on the subepithelial layer were assessed. The distance between the epithelial and the subepithelial tumor edge was measured under microscopic observation, followed by analyses of the relationship between the measured SE and the histological characteristics.

RESULTS

The average and the median SE were 1.1 mm (standard deviation 1.8 mm) and 0.3 mm (range 0-12.3 mm), respectively. The 99th percentile was 8.8 mm. With regard to the histological type, the median SE was significantly greater in diffuse-type tumor than in intestinal-type tumor (0.9 mm vs 0 mm, p < 0.0001). With regard to the location of the subepithelilal tumor edge, the median SE was significantly greater in the submucosal layer than in the mucosal layer (2.6 mm vs 0.3 mm, p < 0.0001).

CONCLUSIONS

In most lesions, the SE was less than 1 cm. A safety margin may be set at 1 cm in EFTR of submucosal EGC.

Endoscopic full-thickness resection: Current status

Conventional endoscopic resection techniques such as endoscopic mucosal resection or endoscopic submucosal dissection are powerful tools for treatment of gastrointestinal neoplasms. However, those techniques are restricted to superficial layers of the gastrointestinal wall. Endoscopic full-thickness resection (EFTR) is an evolving technique, which is just about to enter clinical routine. It is not only a powerful tool for diagnostic tissue acquisition but also has the potential to spare surgical therapy in selected patients. This review will give an overview about current EFTR techniques and devices.

Current applications of endoscopic suturing

Endoscopic suturing had previously been considered an experimental procedure only performed in a few centers and often by surgeons. Now, however, endoscopic suturing has evolved sufficiently to be easily implemented during procedures and is more commonly used by gastroenterologists. We have employed the Apollo OverStitch suturing device in a variety of ways including closure of perforations, closure of full thickness defects in the gastrointestinal wall created during endoscopic full thickness resection, closure of mucosotomies during peroral endoscopic myotomy, stent fixation, fistula closure, post endoscopic submucosal dissection, endoscopic mucosal resection and Natural Orifice Transluminal Endoscopic Surgery defect closures, post-bariatric surgery gastrojejunal anastomosis revision and primary sleeve gastroplasty.

Current innovations in endoscopic therapy for the management of colorectal cancer: from endoscopic submucosal dissection to endoscopic full-thickness resection

Endoscopic submucosal dissection (ESD) is accepted as a minimally invasive treatment for colorectal cancer. However, due to technical difficulties and an increased rate of complications, ESD is not widely used in the colorectum. In some cases, endoscopic treatment alone is insufficient for disease control, and laparoscopic surgery is required. The combination of laparoscopic surgery and endoscopic resection represents a new frontier in cancer treatment. Recent developments in advanced polypectomy and minimally invasive surgical techniques will enable surgeons and endoscopists to challenge current practice in colorectal cancer treatment. Endoscopic full-thickness resection (EFTR) of the colon offers the potential to decrease the postoperative morbidity and mortality associated with segmental colectomy while enhancing the diagnostic yield compared to current endoscopic techniques. However, closure is necessary after EFTR and natural transluminal endoscopic surgery (NOTES). Innovative methods and new devices for EFTR and suturing are being developed and may potentially change traditional paradigms to achieve minimally invasive surgery for colorectal cancer. The present paper aims to discuss the complementary role of ESD and the future development of EFTR. We focus on the possibility of achieving EFTR using the ESD method and closing devices.