Establishment of pure NOTES procedure using a conventional flexible endoscope: review of six cases of gastric gastrointestinal stromal tumors

Comparison of submucosal tunneling biopsy versus EUS-guided FNA for gastric subepithelial lesions: a prospective study with crossover design

BACKGROUND AND STUDY AIMS

Endoscopic ultrasound-guided fine needle aspiration (FNA) for gastrointestinal subepithelial lesions (SELs) has limited diagnostic accuracy due to technical problems and small lesion size. We previously reported a novel submucosal tunneling biopsy (STB) technique for sampling SELs. This study aimed to evaluate the diagnostic ability and safety of STB compared to that of FNA for SELs.

PATIENTS AND METHODS

The study was a non-randomized, prospective comparative study with crossover design in patients with endoluminal gastric SELs. Forty-three patients, including 29 cases with lesions < 2 cm were enrolled. A crossover design with 2 intervention stages (Group A: FNA followed by STB for 23 SELs, Group B: STB followed by FNA for 20 SELs) was implemented. The primary outcome was the diagnostic yield (DY). Secondary outcomes were technical success rate, procedure time, complication rate, and sample quality.

RESULTS

The DY of STB was significantly higher than that of FNA (100 % vs. 34.8 %; P  < 0.0001) in group A, including 100 % in overall STB. The technical success rate of STB was significantly higher than that of FNA (100 % vs. 56.5 %; P  = 0.0006), whereas the median procedure time of STB was significantly longer than that of FNA (37 minutes vs. 18 minutes; P  < 0.0001). The median specimen area of STB samples was markedly larger than that of FNA samples (5.54 mm 2 vs. 0.69 mm 2 ; P  < 0.001). No complications occurred in either method.

CONCLUSIONS

 STB had significantly superior diagnostic ability and a more adequate sample quality than FNA for endoluminal gastric SELs, indicating the suitability of STB for small SELs.

CLINICAL TRIAL REGISTRATION

UMIN 000006754.

Outcomes of gastrointestinal defect closure with an over-the-scope clip system in a multicenter experience: An analysis of a successful suction method

AIM

To demonstrate the clinical outcomes of a multicenter experience and to suggest guidelines for choosing a suction method.

METHODS

This retrospective study at 5 medical centers involved 58 consecutive patients undergoing over-the-scope clips (OTSCs) placement. The overall rates of technical success (TSR), clinical success (CSR), complications, and procedure time were analyzed as major outcomes. Subsequently, 56 patients, excluding two cases that used the Anchor device, were divided into two groups: 14 cases of simple suction (SS-group) and 42 cases using the Twin Grasper (TG-group). Secondary evaluation was performed to clarify the predictors of OTSC success.

RESULTS

The TSR, CSR, complication rate, and median procedure time were 89.7%, 84.5%, 1.8%, and 8 (range 1-36) min, respectively, demonstrating good outcomes. However, significant differences were observed between the two groups in terms of the mean procedure time (5.9 min vs 14.1 min). The CSR of the SS- and TG-groups among cases with a maximum defect size ≤ 10 mm and immediate or acute refractory bleeding was 100%, which suggests that SS is a better method than TG in terms of time efficacy. The CSR in the SS-group (78.6%), despite the technical success of the SS method (TSR, 100%), tended to decrease due to delayed leakage compared to that in the TG-group (TSR, CSR; 88.1%), indicating that TG may be desirable for leaks and fistulae with defects of the entire layer.

CONCLUSION

OTSC system is a safe and effective therapeutic option for gastrointestinal defects. Individualized selection of the suction method based on particular clinical conditions may contribute to the improvement of OTSC success.

Novel and safer endoscopic cholecystectomy using only a flexible endoscope via single port

AIM: To apply the laparoscopic and endoscopic cooperative surgery concept, we investigated whether endoscopic cholecystectomy could be performed more safely and rapidly via only 1 port or not.

METHODS: Two dogs (11 and 13-mo-old female Beagle) were used in this study. Only 1 blunt port was created, and a flexible endoscope with a tip attachment was inserted between the fundus of gallbladder and liver. After local injection of saline to the gallbladder bed, resection of the gallbladder bed from the liver was performed. After complete resection of the gallbladder bed, the gallbladder was pulled up to resect its neck using the Ring-shaped thread technique. The neck of the gallbladder was cut using scissor forceps. Resected gallbladder was retrieved using endoscopic net forceps via a port.

RESULTS: The operation times from general anesthetizing with sevoflurane to finishing the closure of the blunt port site were about 50 min and 60 min respectively. The resection times of gallbladder bed were about 15 min and 13 min respectively without liver injury and bleeding at all. Feed were given just after next day of operation, and they had a good appetite. Two dogs are in good health now and no complications for 1 mo after endoscopic cholecystectomy using only a flexible endoscope via one port.

CONCLUSION: We are sure of great feasibility of endoscopic cholecystectomy via single port for human.

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.

Closure of iatrogenic large mucosal and full-thickness defects of the stomach with endoscopic interrupted sutures in in vivo porcine models: are they durable enough?

BACKGROUND

In this study, we evaluated the technical feasibility of mucosal approximation of large ulcers via an endoscopic suturing system after endoscopic submucosal dissection (ESD), assessed the durability of these sutures, and compared this technique with serosal apposition of full-thickness gastric wall defects using the same device.

METHODS

Post-ESD ulcers were closed with mucosal apposition in 7 pigs, and endoscopic full-thickness resection (EFTR) defects were closed with serosal apposition in 3 pigs. Pigs recovered for 1 week; they were then euthanized and necropsies were performed.

RESULTS

Primary defect closure was achieved in 85.7% of the post-ESD closures and in 100% of the post-EFTR closures (p = 0.67). All pigs survived for 1 week. At necropsy, sutures had loosened in the post-ESD animals, although only minor deformity of the ulcer edges was observed in all repaired post-ESD ulcers. Meanwhile, all of the post-EFTR defect closures were sustained for 1 week.

CONCLUSIONS

Primary closure of post-therapeutic defects can be accomplished using the device. Inverted serosal apposition provides a more durable and reliable repair than everted mucosal apposition.

Analysis of the amount of tissue sample necessary for mitotic count and Ki-67 index in gastrointestinal stromal tumor sampling

There are no established opinions concerning whether the amount of tissue affects the accuracy of histological analyses in gastrointestinal stromal tumors (GISTs). The aim of the present study was to investigate the appropriate amount of tissue sample needed for mitotic count based on the risk classification of GISTs and the Ki-67 index using the following three methods: endoscopic ultrasound-guided fine-needle aspiration (FNA), a novel sampling method called tunneling bloc biopsy (TBB), and biopsy forceps followed by TBB (Bf). Forty-three samples (12 FNA, 17 TBB and 14 Bf) diagnosed as GISTs by immunohistological analysis were utilized. The major and minor axes and overlay area of one piece of specimen (OPS) from the three sampling methods were measured using digital imaging software and were analyzed comparatively regarding the acquisition of histological data. The mean major and minor axes (mm) and overlay areas (mm2) were in the order of TBB > Bf > FNA. The evaluable rates by mitotic count and Ki-67 were, respectively, 75% (9/12) and 83.3% (10/12) for FNA samples, 100% (17/17) and 100% (17/17) for TBB samples, and 100% (14/14) and 100% (14/14) for Bf samples (P>0.05). Three FNA samples were judged unevaluable due to too small specimens in overall diagnosis including mitotic count and Ki-67, calculating the cut-off value for the overlay area of OPS as 0.17 mm2. Comparing the concordance rates between the pre- and post-operative samples, TBB samples was significantly better than FNA (P<0.05). Conclusively, while the amounts of tissues obtained by TBB and Bf are unnecessary for the histological assessment of mitotic count and Ki-67 index, developments of the FNA method are needed to minimize sample error. Considering the technical aspects, as well as the size of the specimens, could help to guide therapeutic planning and improve diagnostic yield for GI subepithelial tumors.

Reduction effect of bacterial counts by preoperative saline lavage of the stomach in performing laparoscopic and endoscopic cooperative surgery

AIM: To investigate the effects of gastric lavage with 2000 mL of saline in laparoscopic and endoscopic cooperative surgery.

METHODS: Twenty two patients who were diagnosed with a gastric gastrointestinal stromal tumor were enrolled. In former term, irrigations of the stomach were conducted whenever it was necessary, not systematically (Non systemic lavage group). In latter term, the stomach was thoroughly cleaned with 2000 mL of saline using an endoscope with a water jet, and Duodenal balloon occlusion was conducted to prevent refluxed bile and pancreatic juice (Systemic lavage+balloon occlusion group). The gastric wall was sprayed with 20 mL of distilled water, and 20 mL of gastric juice was collected in a sterile tube and submitted for culture. 20 mL of ascites was also collected from the laparoscopic ports and submitted for culture. We compared WBC, CRP, BT between two groups, and verify the reduction effect of bacterial counts in Systemic lavage+balloon occlusion group.

RESULTS: WBC count before, 1 d after, and 3 d after laparoscopic and endoscopic cooperative surgery (LECS) were 5060 (95%CI: 4250-9640), 12140 (6050-14110), and 6910 (5320-12520) in Non systemic lavage group, 4400 (3660-7620), 8910 (6480-10980), and 5950 (4840-7860) in Systemic lavage+balloon occlusion group. Significant differences between two groups at the day after LECS (P = 0.029) and the 3 d after LECS (P = 0.042). CRP levels in Non systemic lavage group and in Systemic lavage+balloon occlusion group were significantly different at the day after LECS (P = 0.005) and the 3 d after LECS (P = 0.028). BTs (°C) in Non systemic lavage group and in Systemic lavage+balloon occlusion group were also significantly different at the day after LECS (P = 0.004) and the 3 d after LECS (P = 0.006). In a logarithmic comparison, bacterial load before gastric lavage, after lavage, and ascites culture were 6.08 (95%CI: 4.04-6.97), 0.48 (0-0.85), and 0.21 (0-0.56). The bacterial counts before and after gastric lavage were significantly suppressed (P = 0.007), but no significant difference between gastric juice culture after lavage and ascites (P = 0.154).

CONCLUSION: Pre-LECS lavage with 2000 mL of saline exhibited a bacteria-reducing effect equivalent to disinfectants and obtained favorable results in terms of clinical symptoms and data.

Endoscopic full-thickness resection for gastric submucosal tumors arising from the muscularis propria layer

AIM: To evaluate the efficacy, safety and feasibility of endoscopic full-thickness resection (EFR) for the treatment of gastric submucosal tumors (SMTs) arising from the muscularis propria.

METHODS: A total of 35 gastric SMTs arising from the muscularis propria layer were resected by EFR between January 2010 and September 2013. EFR consists of five major steps: injecting normal saline into the submucosa; pre-cutting the mucosal and submucosal layers around the lesion; making a circumferential incision as deep as the muscularis propria around the lesion using endoscopic submucosal dissection and an incision into the serosal layer around the lesion with a Hook knife; a full-thickness resection of the tumor, including the serosal layer with a Hook or IT knife; and closing the gastric wall with metallic clips.

RESULTS: Of the 35 gastric SMTs, 14 were located at the fundus, and 21 at the corpus. EFR removed all of the SMTs successfully, and the complete resection rate was 100%. The mean operation time was 90 min (60-155 min), the mean hospitalization time was 6.0 d (4-10 d), and the mean tumor size was 2.8 cm (2.0-4.5 cm). Pathological examination confirmed the presence of gastric stromal tumors in 25 patients, leiomyomas in 7 and gastric autonomous nerve tumors in 2. No gastric bleeding, peritonitis or abdominal abscess occurred after EFR. Postoperative contrast roentgenography on the third day detected no contrast extravasation into the abdominal cavity. The mean follow-up period was 6 mo, with no lesion residue or recurrence noted.

CONCLUSION: EFR is efficacious, safe and minimally invasive for patients with gastric SMTs arising from the muscularis propria layer. This technique is able to resect deep gastric lesions while providing precise pathological information about the lesion. With the development of EFR, the indications of endoscopic resection might be extended.

Establishment of the hybrid endoscopic full-thickness resection of gastric gastrointestinal stromal tumors

A prospective observational study was conducted to establish the procedure of hybrid endoscopic full-thickness resection (EFTR) using an existing flexible endoscope. The present study included 16 patients who underwent hybrid EFTR between September 2009 and February 2013 for gastric gastrointestinal stromal tumor (GIST). The patients were selected using the following inclusion criteria for histological findings: Mitotic counts <5/high-power field and immunohistochemical stains positive for KIT or cluster of differentiation 34 (CD34). The mean patient age was 68.2 years (range, 44-81 years); the male-to-female ratio was 6:10; lesion sites at upper (U), middle (M) and lower regions (L) of the stomach were 9/6/1; and the average tumor diameter was 28.3 mm. The mean surgical time was 271 min and the surgical time became progressively faster with each successive surgery. There were 12 and four patients with mitotic counts of <5 and 5-10, respectively, which was significantly different (P=0.01). Immunohistochemical stains showed that tumors from 13 and 10 patients (81.2 and 62.5%, respectively) were positive for KIT and CD34, respectively (P=0.328). All resected surgical margins were negative. According to Fletcher's risk classification, there were five, eight and three patients at an 'extremely low', 'low', and 'intermediate' risk (31.2, 50 and 18.8%, respectively) (P=0.003). The mean postoperative hospital duration was 12.3 days (range, 10-15 days). In conclusion, an ultra-minimally invasive surgery-hybrid EFTR is a safe and established surgical endoscopy procedure.

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.

Submucosal tunneling techniques: current perspectives

Advances in endoscopic submucosal dissection include a submucosal tunneling technique, involving the introduction of tunnels into the submucosa. These tunnels permit safer offset entry into the peritoneal cavity for natural orifice transluminal endoscopic surgery. Technical advantages include the visual identification of the layers of the gut, blood vessels, and subepithelial tumors. The creation of a mucosal flap that minimizes air and fluid leakage into the extraluminal cavity can enhance the safety and efficacy of surgery. This submucosal tunneling technique was adapted for esophageal myotomy, culminating in its application to patients with achalasia. This method, known as per oral endoscopic myotomy, has opened up the new discipline of submucosal endoscopic surgery. Other clinical applications of the submucosal tunneling technique include its use in the removal of gastrointestinal subepithelial tumors and endomicroscopy for the diagnosis of functional and motility disorders. This review suggests that the submucosal tunneling technique, involving a mucosal safety flap, can have potential values for future endoscopic developments.

Pure endoscopic full-thickness resection with peritoneoscopy and omentectomy

OBJECTIVE

To investigate surgical procedures for pure endoscopic full-thickness resection (EFTR) using a flexible endoscope and a prototype of a full thickness suturing device in animal experiments.

METHODS

Six beagles were divided into two groups: sutured with over-the-scope-clip (OTSC group, n = 3) and with a prototype of the double-arm bar suturing system (DBSS group, n = 3). The peritoneoscopy, omentectomy and EFTR procedures were performed through the transgastric route. We examined the surgical procedures required to accomplish pure EFTR and survival rates of these dogs after EFTR.

RESULTS

The duodenal balloon occlusion method maintained a sufficient endoscopic view during peritoneoscopy. Grooves of 10-mm wide were created around the tumor down to the third layer for treating all blood vessels and adding landmark for full-thickness resection lines. Using the muscle layer thin-cutting method, hyaluronic acid was locally injected into the muscle layer and fine incisions were made. Creating tiny perforations provided safe access to the abdominal cavity. Although it was difficult to suture the resected site safely in the OTSC group, the DBSS prototype was useful and reliable for closing there section sites with 3-0 absorbable thread. After EFTR there were no complications in the DBSS group and the dogs were in good health on POD 30, whereas in the OTSC group two dogs died due to dehiscence and gastric juice leaks. Postmortem examinations showed abscess around the suturing sites and two OTSC were detached from the suturing sites.

CONCLUSIONS

Pure EFTR is feasible with DBSS when systematic methods are established. The high safety of full-thickness resection suturing will permit their clinical application in the near future.

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

BACKGROUND

Endoscopic full-thickness resection (EFTR) requires a reliable full-thickness suturing device and an endoscopic counter-traction device to prevent the collapse of the digestive tract.

OBJECTIVE

The present study aimed to assess the reliability of newly developed flexible endoscopy suturing devices and the feasibility of pure EFTR.

METHODS

A total of 30 EFTRs were performed and allocated to three groups (N = 10 for each group). The full-thickness sutures were placed using over-the-scope clips (OTSCs), hand-sewn sutures, or the Double-arm-bar Suturing System (DBSS). Air leak tests were conducted in the three groups. The times required for the placement of one OTSC suture and single-stitch simple interrupted sutures (hand-sewn and DBSS sutures, respectively) were also compared.

RESULTS

All 30 full-thickness sutures were completely and successfully placed. Regarding the air leak tests, the Mann-Whitney U test showed significant differences between OTSC and hand-sewn sutures (p = 0.003). There was also a significant difference between OTSC and DBSS sutures (p = 0.023). There was no significant difference between hand-sewn and DBSS sutures (p = 0.542). A significant difference was found in the suture time for single-stitch simple interrupted sutures among the OTSC, hand-sewn, and DBSS sutures. The Mann-Whitney U test revealed a significant difference between OTSC and hand-sewn sutures (p = 0.0001). There was no significant difference between OTSC and DBSS sutures (p = 0.533), while a significant difference was found between hand-sewn and DBSS sutures (p = 0.0001).

CONCLUSIONS

Pure EFTR is feasible if the mechanical counter traction system is used to expand a small operative field and DBSS is used to make full-thickness sutures. The high safety of full-thickness resection and full-thickness suturing allows for clinical applications of this method.

Current evidence in gastrointestinal surgery: natural orifice translumenal endoscopic surgery (NOTES)

BACKGROUND

Natural orifice translumenal endoscopic surgery (NOTES) is a technique that uses transvisceral access to perform surgical procedures entirely through a natural orifice. Despite the increasing awareness of NOTES, there remain obstacles to its technical feasibility and widespread acceptance. Furthermore, with the paucity of high-level supporting evidence, NOTES currently remains an experimental technique.

OBJECTIVE

This article reviews the goals, applications, technical and practical challenges, and future direction of NOTES in gastrointestinal surgery.

Indications of endoscopic submucosal dissection for symptomatic benign gastrointestinal subepithelial or carcinoid tumors originating in the submucosa

Endoscopic submucosal dissection (ESD) for upper gastrointestinal (GI) subepithelial tumors (SETs) originating in the muscularis propria (MP) layer is associated with numerous issues regarding secure closure and measures against accidental perforation. However, symptomatic benign GI SETs or carcinoid tumors originating in the submucosa (SM) may be safely resected en-bloc using ESD. In this study, the feasibility and safety of ESD as a novel method for endoscopic resection for such GI SETs revealed on endoscopic ultrasonography (EUS) was investigated. A total of 12 consecutive cases of patients with symptomatic benign SETs (n=3; 1 esophageal hemangioma and 2 gastric lipomas) or small carcinoid tumors (n=9; <10 mm, with an extremely low risk of metastasis) originating in the SM as determined on EUS, between March, 2009 and April, 2013, were retrospectively reviewed. The lesions were resected by ESD after confirming that the tumors originated from the SM. The complication rate following en-bloc resection was also determined. En-bloc resection was achieved in all 12 cases, the mean procedure time was 45 min (range, 20-120 min) and no complications occurred intra- or postoperatively. There was no tumor recurrence or disease-related mortality reported during the follow-up period (median follow-up time, 13.4 months). Histopathological curative resection was achieved with ESD without complications in all 9 cases with carcinoid tumors. Therefore, if EUS reveals a SET originating in the SM without infiltration of the MP and resection is indicated due to the presence of abdominal symptoms, ESD may be a feasible option for diagnostic treatment with minimal invasiveness. However, larger-scale prospective studies are required to establish the feasibility and safety of this procedure.

Submucosal tumors: comprehensive guide for the diagnosis and therapy of gastrointestinal submucosal tumors

Small submucosal tumors (SMT) without symptoms are frequently found by endoscopic and radiological examinations. To find proper diagnostic measures and therapeutic indications for histologically undiagnosed SMT, we reviewed published articles in PubMed between 1990 and March 2013 using the key words 'submucosal tumor' and the name of a specific disease. SMT is observed in a wide range of gastrointestinal (GI) diseases and conditions, including compression by extra-GI organs and lesions, congenital tumors, inflammation, and benign as well as malignant neoplastic lesions. In the diagnosis of diseases and decision-making for therapy, endoscopic ultrasonography (EUS) and endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) may play a key role. Symptomatic SMT and SMT histologically diagnosed as malignant or potentially malignant tumors such as gastrointestinal stromal tumor (GIST) should be treated by surgery. SMT >5 cm, SMT increasing in size and those with'high-risk features' including irregular border, heterogeneous internal echo such as anechoic area, and heterogeneous enhancement by contrast media may also be removed by surgery. Laparoscopic approach is feasible for gastric GIST <5 cm and this is considered less invasive than the open approach. Emerging techniques using flexible endoscopes appear less invasive, but require further evidence and are still under clinical study. Correct diagnosis of SMT is challenging; however, EUS and EUS-FNA are useful in the histological diagnosis and clinical decision-making. In the future, minimally invasive approaches may be a mainstream of surgical treatment for small SMT.

Efficacy and safety of over-the-scope clip: Including complications after endoscopic submucosal dissection

AIM: To retrospectively review the results of over-the-scope clip (OTSC) use in our hospital and to examine the feasibility of using the OTSC to treat perforations after endoscopic submucosal dissection (ESD).

METHODS: We enrolled 23 patients who presented with gastrointestinal (GI) bleeding, fistulae and perforations and were treated with OTSCs (Ovesco Endoscopy GmbH, Tuebingen, Germany) between November 2011 and September 2012. Maximum lesion size was defined as lesion diameter. The number of OTSCs to be used per patient was not decided until the lesion was completely closed. We used a twin grasper (Ovesco Endoscopy GmbH, Tuebingen, Germany) as a grasping device for all the patients. A 9 mm OTSC was chosen for use in the esophagus and colon, and a 10 mm device was used for the stomach, duodenum and rectum. The overall success rate and complications were evaluated, with a particular emphasis on patients who had undergone ESD due to adenocarcinoma. In technical successful cases we included not only complete closing by using OTSCs, but also partial closing where complete closure with OTSCs is almost difficult. In overall clinical successful cases we included only complete closing by using only OTSCs perfectly. All the OTSCs were placed by 2 experienced endoscopists. The sites closed after ESD included not only the perforation site but also all defective ulcers sites.

RESULTS: A total of 23 patients [mean age 77 years (range 64-98 years)] underwent OTSC placement during the study period. The indications for OTSC placement were GI bleeding (n = 9), perforation (n = 10), fistula (n = 4) and the prevention of post-ESD duodenal artificial ulcer perforation (n = 1). One patient had a perforation caused by a glycerin enema, after which a fistula formed. Lesion closure using the OTSC alone was successful in 19 out of 23 patients, and overall success rate was 82.6%. A large lesion size (greater than 20 mm) and a delayed diagnosis (more than 1 wk) were the major contributing factors for the overall unsuccessful clinical cases. The location of the unsuccessful lesion was in the stomach. The median operation time in the successful cases was 18 min, and the average observation time was 67 d. During the observation period, none of the patients experienced any complications associated with OTSC placement. In addition, we successfully used the OTSC to close the perforation site after ESD in 6 patients. This was a single-center, retrospective study with a small sample size.

CONCLUSION: The OTSC is effective for treating GI bleeding, fistulae as well as perforations, and the OTSC technique proofed effective treatment for perforation after ESD.

Innovative noninsufflation EFTR: sufficient endoscopic operative field by mechanical counter traction device

BACKGROUND

No reliable pure natural orifice transluminal endoscopic surgery (NOTES) mechanical counter traction (MCT) device for the flexible endoscope to obtain a sufficient surgical endoscopic field has yet been developed. Our experience with 10 cases of hybrid NOTES prompted the realization of the importance of an MCT device for the flexible endoscope and inspired us to establish innovative noninsufflation endoscopic full-thickness resection (EFTR) with an MCT device.

METHODS

We performed 40 EFTR 40 mm in diameter on excised whole porcine stomachs. Twenty were resected by an MCT device to obtain a surgical field (MCT group), and another 20 were resected with a conventional endoscopic attachment (control group). We evaluated the successful resection rates of EFTR and procedure times between two groups. Next, we implemented EFTR with a custom prototype MCT device in three cases of stomach pseudotumors in female dogs. Gastric pseudotumors ~40 mm in diameter were marked within the open surgical field created by the MCT device. After resecting the pseudotumors, we conducted full-thickness suturing using over-the-scope clips.

RESULTS

In the MCT group, all 20 cases were completely resected. On the other hand, in the control group, only 8 cases were performed via EFTR (P < 0.01). The mean ± standard deviation EFTR procedure times for the MCT and control groups were 4.13 ± 0.824 and 36.26 ± 8.67 min, respectively (P = 0.001). In three dogs, sufficient surgical working spaces were obtained up to 78 mm (range, 65-78 mm), and full-thickness resections were performed safely and sutured with over-the-scope clips.

CONCLUSIONS

Our new prototype MCT device effectively obtains a sufficient surgical endoscopic field during EFTR. We are developing a new MCT with a bending function to perform EFTR in any location in the stomach.

The Performance of Multiple Transgastric Procedures Using the Natural Orifice Transluminal Endoscopic Surgery Technique: Is Pure NOTES Satisfactory?

Background/Aims

Although several groups have demonstrated the usefulness of natural orifice transluminal endoscopic surgery (NOTES), there is still concern about frequent serious adverse events. We performed this study to determine the technical feasibility and safety of pure NOTES with a transgastric approach in a porcine model from the endoscopist's point of view.

Methods

Diagnostic peritoneoscopy, liver biopsy, salpingo-oophorectomy, and Fallopian tube ligation with a transgastric approach using a two-channel therapeutic endoscope were performed in 10 healthy female minipigs. These procedures were performed in two acute models and eight survival models in consecutive order.

Results

The technical success rate was 100% for peritoneoscopy (10/10), liver biopsy (5/5), salpingo-oophorectomy (10/10), and Fallopian tube ligation (10/10). Eight cases of adverse events occurred, including one case of splenic injury, one case of bleeding after liver biopsy, two cases of small bowel adhesion after salpingo-oophorectomy, two cases of hematoma at the salphingo-oophorectomy site, and two cases of partial dehiscence at the gastric closure site. The gastric puncture site was closed with seven to eight hemoclips in four cases and two hemoclips and an endoloop in four cases.

Conclusions

The use of pure NOTES for peritoneoscopy, liver biopsy, salpingo-oophorectomy, and Fallopian tube ligation may be technically feasible, but considerable adverse events can occur during or after the procedure. Further studies utilizing specialized techniques overcome several limitations of pure NOTES are therefore necessary.

Gastric surgery and notes

Rather than being an end point in and of itself, NOTES offers an approach that encompasses the potential use of a natural orifice in conjunction with flexible instruments as a less invasive and more cosmetically appealing method of performing certain surgical procedures. Gastric surgery through natural orifices is one of the cutting-edge procedures in the evolving field of NOTES. The potential indications for NOTES involve a wide spectrum of upper gastrointestinal diseases, including achalasia, reflux disease, submucosal tumors, cancer, and morbid obesity. Although NOTES is becoming more widely used, most studies still involve only small numbers of patients, and the design of larger series and comparative trials to evaluate the early indications and results of NOTES is needed.