Long-term outcomes of endoscopic ultrasonography-guided balloon-occluded gastrojejunostomy bypass for malignant gastric outlet obstruction (with video).

BACKGROUND AND AIMS: Endoscopic ultrasonography-guided gastroenterostomy (EUS-GE) is a minimally invasive technique for gastric outlet obstruction (GOO). EUS-guided balloon-occluded gastrojejunostomy bypass (EPASS) aims to improve stent deployment and minimize migration in EUS-GE. In this study, we evaluated the long-term outcomes of EPASS. METHODS: We retrospectively analyzed 37 patients (mean age 71; 21 males) with symptomatic, non-refractory GOO who had undergone EPASS. RESULTS: EPASS achieved a 94.6 % (35/37) technical success rate including 2 cases of stent mis-deployment. The mean procedure time was 27.3 min, with a double-balloon tube insertion time of 10.4 min. Initial GOO scores improved from 0.43 to 2.14 and 2.60 at 7 and 28 days post-EPASS, respectively. The clinical success rate was 89.2%. The rate of adverse events, including fever and abdominal pain, was 16.2%. The mean overall survival post-EPASS was 193.5 days, with no stent occlusion or migration (100% patency). CONCLUSIONS: EPASS demonstrates safety and reliability in EUS-GE, offering a viable option for symptomatic malignant GOO treatment.

Long-term outcomes after EUS-guided antegrade intervention for benign bilioenteric anastomotic stricture.

BACKGROUND AND AIMS: Bilioenteric anastomotic stricture (BES) is a well-known adverse event after bilioenterostomy. Recently, EUS-guided antegrade intervention (EUS-AI) has been developed for cases that are difficult to treat by balloon enteroscopy-assisted ERCP. However, no data are available on the long-term outcomes after EUS-AI. The main goal of the present study was to clarify the long-term outcomes of EUS-AI in such patients. METHODS: Between November 2013 and November 2021, 34 patients who were followed for more than 1 year after EUS-AI for BES were identified. The primary endpoint was the rate of stricture resolution. Secondary endpoints were factors associated with stricture resolution, rate of BES recurrence, rate of conversion to surgery, and rate of hepatic fibrosis progression during follow-up. RESULTS: The median follow-up period was 56.7 months. Stricture resolution was achieved in 17 of 34 patients (50%). A multivariate analysis confirmed that the presence of bile duct stones (odds ratio, 9.473; 95% confidence interval, 1.66-53.98; P = .01) was significantly associated with stricture resolution. The stricture recurrence rate was 33%, and the median time from stent removal to recurrence was 31.2 months. Four patients underwent surgery because of recurrent cholangitis. During the median follow-up period of 56.7 months, 25% progressed to hepatic fibrosis based on the Fibrosis-4 index grade. Interestingly, patients without cholangitis during follow-up did not show progression of hepatic fibrosis. CONCLUSIONS: EUS-AI has achieved acceptable long-term clinical outcomes. EUS-AI can be a viable alternative treatment of choice before surgical treatment in patients who are difficult to treat by conventional approaches.

Optimal mode and power output of electrosurgical units for endoscopic papillectomy based on animal experiments and a preliminary clinical study (with videos).

BACKGROUND AND AIMS: The optimal electrosurgical unit (ESU) settings for endoscopic papillectomy (EP) have not been investigated. We conducted animal experiments to determine the optimal endoCUT settings with VIO (Erbe, Tübingen, Germany) ESUs and then conducted a small clinical study. METHODS: Dedicated animal experimental models were created. To investigate the incision force, chicken meat was resected with a snare whose handle was a hung weight. To investigate the coagulation effect, a surgical needle electrode was inserted into a pig liver and energized, and to determine changes over time in the coagulation status, simulated EP was performed using a living pig. These experiments were performed using the knife-setting or snare-setting endoCUT modes and various effect, duration, and interval settings and compared with results for ICC (Erbe) ESUs. Based on the results, we performed EP in a small number of patients. RESULTS: The main factor affecting the incision force was duration. The coagulation effect was related to not only effect but also duration. In the endoCUT mode, knife-setting produced a higher incision force and lower coagulation effect. The nondischarge coagulation effect may cause deep ulceration. Based on the animal experiments, we concluded the ideal ESU setting for EP, "VIO EP mode," is knife-setting with high duration, lowest effect, and low interval settings. In the clinical study, there were no significant adverse events such as bleeding, pancreatitis, or perforation. CONCLUSIONS: "VIO EP mode" seems to afford optimal papillectomy. Larger scale clinical studies are needed to accumulate further data and make clinical comparisons with the ICC ESU.

Clinical practice guidelines for endoscopic papillectomy.

The Japan Gastroenterological Endoscopy Society has developed the "Clinical Practice Guidelines for Endoscopic Papillectomy (EP)" as a fundamental guideline using scientific approach. EP is a recently spreading therapeutic modality for ampullary tumors ranked as high risk endoscopic technique. Because of the paucity of high level of evidence, strength of recommendations had to be determined by a consensus among specialists. These guidelines, shed light on the following five issues: Indications, Preoperative/intraoperative preparations and techniques, Early adverse events, Therapeutic outcomes and remnants/recurrences, and Follow-up and late adverse events, to guide current clinical practice on EP.

New deployment techniques of the lumen-apposing metal stent in walled-off necrosis filled with necrotic tissue: Chick opening its mouth (with video).

The lumen-apposing metal stent (LAMS) on an electrocautery-enhanced delivery system for endoscopic ultrasound-guided transluminal drainage has been widely used for the treatment of walled-off necrosis (WON). However, deployment of the LAMS can be technically difficult in WON, which contains a large amount of necrotic tissue and a low liquid component, owing to insufficient space for expansion of the distal stent flange. It has been recommended that the LAMS is placed in WON containing necrotic tissue, because additional endoscopic necrosectomy can be readily performed via the lumen of the LAMS. Here we introduce two new deployment techniques of the LAMS for WON filled with necrotic tissue, namely, the two-step puncture technique and the back-and-forth technique, which enable the distal stent flange to be expanded like a chick opening its mouth. These techniques are expected to further improve the clinical outcomes of refractory WON.

Impact of electrical pulse cut mode during endoscopic papillectomy: Pilot randomized clinical trial.

OBJECTIVE: Endoscopic papillectomy is increasingly being used for ampullary adenoma treatment. However, it remains challenging despite increased safety with treatment advances. The ideal power output and electrosurgical current mode for mucosal resection are not established. We aimed to identify the ideal electrical pulse for use during resection. METHODS: This pilot randomized, single-blind, prospective, multicenter trial, recruited patients with ampullary adenomas and conventional anatomy who were scheduled to undergo endoscopic papillectomy. Endoscopic treatment was performed using a standardized algorithm and patients were randomized for endoscopic papillectomy with Endocut or Autocut. The primary outcome was the incidence of delayed bleeding. Incidence of procedure-related pancreatitis, successful complete resection, pathological findings, and other adverse events were secondary endpoints. RESULTS: Sixty patients were enrolled over a 2-year period. The incidences of delayed bleeding (13.3% vs. 16.7%, P = 1.00) and pancreatitis (27% vs. 30%, P = 0.77) were similar between both groups. The rate of crush artifacts was higher in the Endocut than in the Autocut group (27% vs. 3.3%, P = 0.03). Immediate bleeding when resecting tumors greater than 14 mm in diameter was more common in the Autocut than in the Endocut group (88% vs. 46%, P = 0.04). CONCLUSIONS: The Autocut and Endocut modes have similar efficacy and safety for endoscopic papillectomy. The Endocut mode may prevent immediate bleeding in cases with large tumor sizes, although it causes more frequent crush artifacts. REGISTRY AND THE REGISTRATION NUMBER: The Japanese UMIN Clinical Trials Registry (UMIN-CTR: 000021382).

EUS-guided antegrade intervention for benign biliary diseases in patients with surgically altered anatomy (with videos).

BACKGROUND AND AIMS: Although balloon enteroscopy-assisted ERCP (BE-ERCP) is effective and safe for benign biliary diseases in patients with surgically altered anatomy (SAA), BE-ERCP is not always successful. Recently, EUS-guided antegrade intervention (EUS-AI) by using a 1-stage or 2-stage procedure has been developed for BE-ERCP failure cases. The aim of the present study was to evaluate the outcome of EUS-AI for benign biliary diseases in patients with SAA. METHODS: Of 48 patients in whom BE-ERCP failed, percutaneous transhepatic intervention was performed in 11. From November 2013 until November 2017, we retrospectively reviewed cases of an additional 37 patients with SAA who failed BE-ERCP and underwent EUS-AI for benign biliary diseases (common bile duct stones [n = 11], intrahepatic bile duct stones [n = 5], anastomotic strictures [n = 21]). RESULTS: The overall technical success of the creation of the hepatoenteric tract by EUS was 91.9% (34/37). Moderate adverse events were observed in 8.1% (biliary peritonitis [n = 3]). One-stage EUS-AI by EUS succeeded in 8 cases (100%) without any adverse events. In another 26 cases, 2-stage EUS-AI by ERCP was performed about 1 or 2 months later. Endoscopic antegrade therapy under fluoroscopy was successful in 6 cases. Per-oral cholangioscopy-assisted antegrade intervention was required in 19 cases (guidewire manipulation across the anastomotic stricture [n = 6], cholangioscopy-guided lithotripsy by using electrohydraulic lithotripsy [n = 13]). In 1 case, magnetic compression anastomosis was performed. The final clinical success rate of all EUS-AIs was 91.9%. CONCLUSIONS: EUS-AI for benign biliary diseases in patients with SAA appears to be a feasible and safe alternative procedure after BE-ERCP failure.

Ex vivo assessment of anchoring force of covered biflanged metal stent and covered self-expandable metal stent for interventional endoscopic ultrasound.

BACKGROUND AND AIMS: Endoscopic ultrasound (EUS)-guided transmural drainage using a covered biflanged metal stent (CBFMS) and a conventional tubular biliary covered self-expandable metal stent (CSEMS) has recently been performed by EUS experts. However, appropriate traction force of the sheath to prevent the migration during stent deployment is well unknown. Herein, we assessed the anchoring force (AF) of the distal flange in CBFMSs and CSEMSs. METHODS: The AFs of four CBFMSs (Stents AX, NG, PL, and SX) and six CSEMSs (Stents BF, BP, EG, HN, SP, and WF) were compared in an ex vivo setting. We assessed the AF produced by each stent using an EUS-guided transmural drainage model and an EUS-guided hepaticogastrostomy model consisting of sheet-shaped specimens of the stomach, gelatin gel, and gelatin tubes. RESULTS: For CBFMSs, the maximum AF of Stent AX was significantly higher than those of Stents PL and SX (P < 0.05) in the porcine model. In the gelatin series, all stents except Stent NG showed a nearly similar AF. For CSEMSs, Stents HN, EG, BF, and WF showed gradual AF elevation in the porcine stomach. Stents SP and BP showed a lower AF than the other four stents. For the gelatin setting, the maximum AF of Stents HN, EG, and WF was higher than those of the other stents regardless of the type of specimens. CONCLUSIONS: The significance of the AF and traction distance according to the property of various CBFMSs and CSEMSs could be elucidated using ex vivo models.

Expanding the indication of endoscopic papillectomy for T1a ampullary carcinoma.

BACKGROUND AND AIM: Endoscopic papillectomy (EP) has been attempted not only for benign lesions but also for early ampullary carcinoma (AC). However, there is still no sufficient evidence or consensus regarding the effectiveness of EP for early AC. Herein, we evaluated the expanding indication of EP for early AC. METHODS: Between May 1999 and December 2016, 177 patients were diagnosed with ampullary tumor before undergoing EP, and their clinical and histopathological data were analyzed retrospectively. RESULTS: There were 27 Tis-T1a AC patients and four T1b AC patients who underwent EP. Mean tumor size was 14.1 mm for Tis-T1a AC and 17.0 mm for T1b AC. For the histological grade, 50% (2/4) of T1b AC were moderately differentiated, whereas 96.3% (26/27) of Tis-T1a AC were well differentiated and papillary. For lymphovascular invasion, one (25%) occurred in T1b AC but none occurred in Tis-T1a AC. There was no AC recurrence from the date of EP until a maximum of 5 years (Tis-T1a: mean period 48.5 months [5-60]; T1b: mean period 26.5 months [3-60]). CONCLUSIONS: Endoscopic papillectomy is useful and reliable for the curative treatment of T1a AC. Large-scale prospective studies with long-term follow up are needed.

Novel peroral direct digital cholangioscopy-assisted lithotripsy using a monorail technique through the overtube in patients with surgically altered anatomy (with video).

Efficacy of cholangioscopy-assisted lithotripsy for difficult stones such as huge stones, multiple large stones and an impacted stone in patients with non-altered anatomy has been reported. Herein, we describe peroral direct digital cholangioscopy (PDCS)-assisted electrohydraulic lithotripsy (EHL) with a new technique in patients with surgically altered anatomy. Five patients received PDCS-assisted EHL with the monorail technique due to failed conventional stone extraction. Balloon enteroscope was removed, leaving the stiff guidewire in the bile duct and an overtube with inflated balloons. The cholangioscope was then inserted into the bile duct over the wire through the overtube. After direct visualization of the stone, PDCS-assisted EHL was carried out. This technique was named the 'monorail technique'. Complete removal of biliary stones in one session was accomplished in four patients and only one case required two sessions. There was no adverse event in any of the cases. PDCS-assisted EHL using the monorail technique was effective and safe for difficult biliary stones in patients with surgically altered anatomy.

Novel ex vivo training model for freehand insertion using a double-bending peroral direct cholangioscope.

BACKGROUND AND AIM: Several experts of direct peroral videocholangioscopy (D-PVCS) using a conventional ultraslim endoscope have reported its usefulness for the diagnosis and therapy of biliary tract diseases. We have additionally developed a dedicated double-bending D-PVCS technique for freehand scope insertion. In this study, we developed an ex vivo training model for the freehand double-bending D-PVCS technique and compared it with the technique using a conventional ultraslim endoscope. METHODS: The ex vivo model was made for training using a U-shape insertion pattern. A third prototype endoscope and an ultraslim upper gastrointestinal endoscope were used. Two experts and nine non-experts performed D-PVCS using the freehand technique. RESULTS: The two experts could not advance the tip of the endoscope to the hilar portion using the freehand technique, but they could achieve technical successful insertion to the hilar portion with the third prototype cholangioscope using the freehand technique alone. The non-experts could not advance the tip of the endoscope to the bile duct using the freehand technique. On the other hand, two (22.2%) non-experts could advance the tip of the third prototype cholangioscope using the freehand technique before the training conducted by the experts. After the training, all the non-experts could advance the tip of the third prototype cholangioscope to the hilar portion. CONCLUSIONS: The novel ex vivo model using a third prototype cholangioscope was useful for training in the use of the freehand D-PVCS technique.

Shaking table tests of a one-quarter scale model of concrete hollow block masonry houses retrofitted with fiber-reinforced paint.

Unreinforced masonry (URM) buildings are prone to significant damage when subjected to ground motion. Some strengthening methods have been proposed to increase the seismic capacity. However, the widespread adoption of these methods faces various challenges, including economic constraints experienced by common people in developing countries, the complexity of implementation, efficiency, and seismic safety of each technique. This paper introduces a new retrofitting method of fiber-reinforced paint using fiberglass as the primary reinforcing material. The advantage of this technique lies in its simplicity and ease of application, with the added benefit of using the paint to improve the appearance of the house. Two 1:4 scale concrete hollow block (CHB) masonry houses were constructed to represent unreinforced masonry and retrofitted masonry structures using fiber-reinforced paint (FR-Paint). The shaking table test results indicate that the retrofitted house model showed improvements of up to 18 times in deformation capacity and up to 13 times in energy dissipation compared to the non-retrofitted house model. FR-Paint has a robust performance even in high input motion at a seismic intensity JMA of 7 (Japan Meteorological Agency). This confirms that this retrofitting method has a high earthquake-resistant performance.

Potential versatile uses of a novel ultra-thin peroral cholangioscope.

Tonozuka and colleagues report the usefulness of a newly developed ultra-thin mother-baby type peroral cholangioscope with a tip external diameter of 2.3 mm for a case of biliary stricture in which conventional peroral cholangioscope insertion was challenging. The novel scope allows simple and low-cost peroral cholangioscopy, making it highly versatile.

Early and late effects of endoscopic interventions in patients with malignant afferent loop syndrome: A single-center experience and literature review.

BACKGROUND/PURPOSE: Afferent loop syndrome (ALS) is a rare adverse event after gastrointestinal surgery requiring appropriate early decompression treatment. Several endoscopic interventions have been attempted for treatment, including endoscopic enteral metal stent placement (EMSP), endoscopic ultrasound (EUS)-guided entero-enterostomy (EUS-EE), and EUS-guided hepaticogastrostomy (EUS-HGS). However, there are limited data on outcomes, including duration of stent patency. In this study, we evaluated the usefulness of each endoscopic intervention for malignant ALS. METHODS: We retrospectively investigated nine patients with malignant ALS who underwent EMSP, EUS-EE, or EUS-HGS. Information on technical success, clinical efficacy, adverse events, stent dysfunction, and overall survival was collected and analyzed. RESULTS: The most common symptoms were abdominal pain and cholangitis. ALS was treated by EMSP in three patients, EUS-EE in three patients, and EUS-HGS in three patients. Stent placement was successful and clinically effective in all patients with no adverse events. During follow-up, stent dysfunction occurred in two patients treated by EUS-HGS. Eight patients died of primary disease during a median follow-up of 157 days. CONCLUSIONS: Each of the available endoscopic interventions for malignant ALS can be expected to produce similar outcomes, including duration of stent patency. The choice of endoscopic intervention should be made based on the characteristics of each treatment.