Dielectrophoretic Capture of Cancer-Derived Small-Extracellular-Vesicle-Bound Janus Nanoparticles via Lectin-Glycan Interaction.

Glycosylation is closely related to cellular metabolism and disease progression. In particular, glycan levels in cancer cells and tissues increase during cancer progression. This upregulation of glycosylation in cancer cells may provide a basis for the development of new biomarkers for the targeting and diagnosis of specific cancers. Here, they developed a detection technology for pancreatic cancer cell-derived small extracellular vesicles (PC-sEVs) based on lectin-glycan interactions. Lectins specific for sialic acids are conjugated to Janus nanoparticles to induce interactions with PC-sEVs in a dielectrophoretic (DEP) system. PC-sEVs are selectively bound to the lectin-conjugated Janus nanoparticles (lectin-JNPs) with an affinity comparable to that of conventionally used carbohydrate antigen 19-9 (CA19-9) antibodies. Furthermore, sEVs-bound Lectin-JNPs (sEVs-Lec-JNPs) are manipulated between two electrodes to which an AC signal is applied for DEP capture. In addition, the proposed DEP system can be used to trap the sEVs-Lec-JNP on the electrodes. Their results, which are confirmed by lectin-JNPs using the proposed DEP system followed by target gene analysis, provide a basis for the development of a new early diagnostic marker based on the glycan characteristics of PC-sEVs. In turn, these novel detection methods could overcome the shortcomings of commercially available pancreatic cancer detection techniques.

Clinical correlation of cholelithiasis in patients undergoing percutaneous endoscopic gastrostomy.

The risk factor for cholelithiasis include low physical activity. With an aging society, the number of bedridden patients who undergo percutaneous endoscopic gastrostomy (PEG) has increased, and cholelithiasis has often been found in these patients. This study aimed to evaluate the risk factors correlated with cholelithiasis in adults who underwent PEG. This retrospective single-center design study reviewed patients who underwent PEG and were confirmed to have cholelithiasis through imaging from March 1996 to December 2021. The investigated variables were age, sex, body mass index (BMI, kg/m2), cause of PEG insertion, initial physical activity status, laboratory findings on PEG insertion day, and incidence of acute cholecystitis. The differences between categorical and continuous variables were analyzed using Student's t test and chi-square test. We enrolled 576 eligible patients who underwent PEG insertion. A total of 161 patients were detected with cholelithiasis (28.0%). The overall independent risk factors for cholelithiasis in patients who underwent PEG insertion were increased C-reactive protein (CRP) levels and decreased physical activity status (bedridden state). The incidence of cholelithiasis was increased by up to 30.7%, especially in patients with bedridden status. However, the incidence of acute cholecystitis among cholelithiasis group was only 5.6%. BMI and total cholesterol were positively correlated with the size of gallbladder (GB) stones. One of the major risk factors for cholelithiasis is decreased physical activity, especially in patients who underwent PEG insertion. Abdominal imaging is recommended to confirm the presence of cholelithiasis and to consider prophylaxis for cholelithiasis, especially in bedridden patients with elevated initial CRP levels at the time of PEG insertion.

Role of Probiotics in Preventing Carbapenem-Resistant Enterobacteriaceae Colonization in the Intensive Care Unit: Risk Factors and Microbiome Analysis Study.

Older patients with multiple comorbidities often necessitate prolonged hospital stays and antibiotic treatment in the intensive care unit (ICU), leading to a rise in multidrug-resistant organisms like carbapenem-resistant Enterobacteriaceae (CRE). This study examined risk factors for carbapenem-resistant Enterobacteriaceae colonization in the ICU and assessed probiotics' preventive role. In this single-center, retrospective study, 9099 ICU patients were tested for stool CRE culture from March 2017 to April 2022. We excluded 136 patients with CRE colonization within one week post-admission and 26 who received probiotics before CRE colonization. Ultimately, 8937 CRE-negative patients were selected. Logistic analysis identified CRE colonization risk factors and evaluated probiotics' influence, including Saccharomyces boulardii or Lactobacillus rhamnosus, used by 474 patients (5.3%) in the ICU. Compared with data on initial admission, 157 patients (1.7%) had newly discovered CRE colonization before discharge. In a multivariate analysis, coronavirus disease 2019, the ICU, tube feeding, antibiotics such as aminoglycoside, extended-spectrum penicillin, stool vancomycin-resistance enterococci colonization, and chronic kidney disease were significantly associated with de novo CRE infection. However, probiotic use was negatively correlated with CRE infection. Managing risk factors and administering probiotics in the ICU may help prevent CRE colonization; large randomized prospective studies are needed.

Prognostic Impact of Minimal Pelvic Fluid in Locally Advanced Pancreatic Cancer: A Multicenter Retrospective Study.

BACKGROUND/AIMS: Minimal pelvic fluid (MPF) is occasionally encountered on computed tomography (CT) scans during the initial staging of newly diagnosed pancreatic cancer. However, its clinical relevance has scarcely been studied. This study intends to explore the incidence of minimal pelvic fluid and its relevance in terms of survival in locally advanced pancreatic cancer (LAPC) patients. MATERIALS AND METHODS: The medical records of patients with LAPC at 4 tertiary referral institutions were retrospectively reviewed from January 2005 to December 2015. Minimal pelvic fluid was defined as a fluid collection volume in the pelvic cavity of <100 mL as determined by abdominal CT. The association between the presence of MPF and patient survival was evaluated. RESULTS: A total of 59 patients (male:female, 33:26; median age, 68 years; range 46-82 years) with LAPC were enrolled. Of the 59 patients, 22.0% (n = 13) had MPF, and 78.0% (n = 46) had no pelvic fluid (NPF). Baseline clinical characteristics in the 2 groups, including extent of the tumor stage, extent of spread to the lymph nodes stage, and pattern of treatments, were not significantly different. However, median overall survival was significantly less in the MPF group [9.7 months, (95% CI, 5.9-13.5)] than in the NPF group as determined by the log-rank test [16.9 months, (95% CI, 9.3-24.5)] (P = .002), and univariate and multivariate analyses showed that the presence of MPF independently predicted a poor prognosis. CONCLUSION: The presence of MPF was found to be significantly associated with reduced survival and an independent poor prognostic biomarker in LAPC patients.

Finding the ideal sedative: a non-inferiority study of remimazolam vs propofol in endoscopic retrograde cholangiopancreatography.

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) requires an ideal sedative that provides a predictable action duration and meets safety requirements. We compared the efficacies and safeties of remimazolam and propofol in patients who had undergone ERCP. METHODS: In this prospective, randomized, single-blind, single-center study, we compared the performances of remimazolam and propofol for inpatient ERCP. Study medications were administered under the supervision of an endoscopist. One hundred and ten patients scheduled to undergo ERCP were randomly assigned to receive remimazolam or propofol. The primary endpoint was a composite of successful completion of the procedure and no requirement for rescue medication. Secondary endpoints included sedation efficacy, recovery time, and adverse events. RESULTS: Of the 110 patients randomized, 108 underwent sedation, and ERCP (53 received remimazolam and 55 propofol). The primary endpoint was met for remimazolam and propofol in 100% of patients in both arms. Incidences and frequencies of emergent adverse events, including desaturation, requiring treatment were comparable in both arms. However, ERCP was started sooner in the propofol arm (mean, 63.18 ± 16.56 s) than in the remimazolam arm (75.23 ± 32.27 s; P-value = 0.02). Time to full alertness after ERCP was also significantly shorter in the propofol arm (304.18 ± 146.25 vs 448.34 ± 224.09 s; P-value <0.001). CONCLUSION: Remimazolam is not inferior to propofol in achieving successful ERCP completion without rescue medication. Incidences of adverse events were comparable. Remimazolam is a safe and effective alternative to propofol for ERCP sedation, expanding options for clinicians and improving patient outcomes.

Efficacy Analysis of Suprapapillary versus Transpapillary Self-Expandable Metal Stents According to the Level of Obstruction in Malignant Extrahepatic Biliary Obstruction.

Background/Aims: The use of a self-expandable metal stent (SEMS) is recommended for unresectable malignant biliary obstruction (MBO). Stent-related adverse events might differ according to the position of the stent through the ampulla of Vater (AOV). We retrospectively evaluated SEMS patency and adverse events according to the position of the SEMS. Methods: In total, 280 patients who underwent endoscopic SEMS placement due to malignant distal biliary obstruction were analyzed retrospectively. Suprapapillary and transpapillary SEMS insertions were performed on 51 patients and 229 patients, respectively. Results: Between the suprapapillary group (SPG) and transpapillary group (TPG), the stent patency period was not significantly different (median [95% confidence interval]: 107 days [82.3 to 131.7] vs 120 days [99.3 to 140.7], p=0.559). There was also no significant difference in the rate of adverse events. In subgroup analysis, the stent patency for an MBO located within 2 cm from the AOV was found to be significantly shorter than that for an MBO located more than 2 cm from the AOV in the SPG (64 days [0 to 160.4] vs 127 days [82.0 to 171.9], p<0.001) and TPG (87 days [52.5 to 121.5] vs 130 [97.0 to 162.9], p<0.001). Patients with an MBO located within 2 cm from the AOV in both groups had a higher percentage of duodenal invasion (SPG: 40.0% vs 4.9%, p=0.002; TPG: 28.6% vs 2.9%, p<0.001) than patients with an MBO located more than 2 cm from the AOV. Conclusions: The SPG and TPG showed similar results in terms of stent patency and rate of adverse events. However, patients with an MBO located within 2 cm from the AOV had a higher percentage of duodenal invasion with shorter stent patency than those with an MBO located more than 2 cm from the AOV, regardless of stent position.

Development of novel biliary metal stent with coil-spring structure and its application in vivo swine biliary stricture model.

Background: As of date, endoscopic biliary stenting with plastic stent (PS) and self-expandable metal stent (SEMS) have been widely used for the palliation of biliary tract strictures. However, these two stents have several limitations regarding the management of biliary strictures caused by intrahepatic and hilar cholangiocarcinoma. PS has short patency and also risks bile duct injury and bowel perforation. SEMS is difficult to revise when occluded by tumor overgrowth. To compensate for such shortcomings, we developed a novel biliary metal stent with coil-spring structure. The aim of this study was to investigate the feasibility and efficacy of the novel stent in a swine model. Methods: The biliary stricture model was prepared in six mini-pigs using endobiliary radiofrequency ablation. Conventional PS (n=2) and novel stents (n=4) were deployed endoscopically. Technical success was defined as successful stent placement and clinical success was defined as >50% reduction of serum bilirubin level. Adverse events, stent migration, and endoscopic removability for one month after stenting were also assessed. Results: The biliary stricture was successfully created in all animals. The technical success rate was 100 %, and the clinical success rate was 50% in the PS group and 75% in the novel stent group. In the novel stent group, the median pre- and post-treatment serum bilirubin levels were 3.94 and 0.3 mg/dL. Stent migration occurred in two pigs and two stents were removed by endoscopy. There was no stent-related mortality. Conclusions: The newly designed biliary metal stent was feasible and effective in a swine biliary stricture model. Further studies are needed to verify the usefulness of the novel stent in the management of biliary strictures.

A novel bipolar electrocautery-enhanced delivery system with a lumen-apposing metal stent for EUS-guided drainage: A porcine study.

BACKGROUND: An electrocautery-enhanced delivery system with a lumen-apposing metal stent (LAMS) is available for one-step endoscopic ultrasound-guided transmural drainage (EUS-TD). Bipolar electrosurgery has several potential clinical advantages, including reduced collateral thermal damage, enhanced hemostasis, and no requirement for a return electrode plate. In this study, we compared the technical feasibility and safety of a newly developed bipolar electrocautery-enhanced delivery system with a conventional delivery system for EUS-TD using a LAMS in a porcine model. METHOD: Ten days before the study, 12 mini pigs underwent common bile duct ligation for EUS-guided gallbladder drainage. Transenteric puncture was performed, followed by placement of a guidewire. In six pigs, a bipolar electrocautery-enhanced delivery system with LAMS (Hot SPAXUS) was inserted over the guidewire and advanced into the gallbladder, without prior dilation of the tract, by applying a bipolar cut current. In the remaining six pigs, a conventional delivery system with LAMS (Cold SPAXUS) was inserted after tract dilatation using a cystotome. The stent was removed after 4 weeks. RESULTS: In all pigs, the stent was successfully inserted and deployed in the gallbladder without adverse events. The mean procedure time of EUS-TD was significantly lower in the Hot SPAXUS group than that of the Cold SPAXUS group (mean ± standard deviation: 188.7 ± 5.2 vs 449.5 ± 97.5 s, P = .0019). Stent migration was not observed, and all stents were removed successfully. CONCLUSIONS: Endoscopic ultrasound-guided transmural drainage using a bipolar electrocautery-enhanced LAMS is feasible for reducing the procedure time while maintaining the high success rate and safety of conventional LAMS.

Efficacy analysis of hemostatic spray following endoscopic papillectomy: A multicenter comparative study.

BACKGROUND AND AIM: Endoscopic post-papillectomy bleeding is a serious adverse event with a prevalence ranging from 2% to 45.3%. Conventional hemostatic methods, including diluted epinephrine injection before papillectomy or argon plasma coagulation after papillectomy, did not show a preventive role in reducing immediate or delayed post-papillectomy bleeding. Therefore, we aimed to assess the efficacy and safety of a hemostatic powder spray for post-papillectomy bleeding and compare with those of conventional modalities. METHODS: Patients who underwent endoscopic papillectomy were enrolled in five tertiary hospitals. The group was divided into hemostatic spray and conventional control groups according to the bleeding control methods. The main outcome measurements were delayed bleeding rate and any adverse events related to the procedures. RESULTS: A total of 40 patients who received a hemostatic spray (n = 18) or conventional hemostatic methods (n = 22) after endoscopic papillectomy were included. The prevalence of delayed bleeding was not different in the two groups: 27.8% and 36.4% in hemostatic spray and conventional control groups (P = 0.564), respectively. The adverse events such as post-papillectomy pancreatitis and cholangitis were not different in the two groups. There were no procedure-related mortalities. CONCLUSION: Hemostatic spray is technically feasible and safe for the prevention or management of post-papillectomy bleeding. Hemostatic spray can be one of the options for post-papillectomy bleeding control methods owing to its convenient use.

Preclinical evaluation of endoscopic placement of a steroid-eluting metal stent in an in vivo porcine benign biliary stricture model.

Treatment of benign biliary strictures (BBS) using fully covered self-expandable metal stents (FCSEMS) has a high success rate, but recurrence can occur. Corticosteroids may be useful based on their anti-fibrotic and anti-inflammatory effects. We investigated the safety and efficacy of corticosteroid-eluting FCSEMS in an animal model. BBSs were created by radiofrequency ablation in 12 mini-pigs. Four weeks later, FCSEMS coated with 0 mg (control), 15 mg (steroid 1 × group), or 30 mg (steroid 2 × group) triamcinolone were inserted endoscopically. The in vitro drug release assay revealed that the optimal stent had 15 mg of triamcinolone and a hydrophilic membrane. No transmural necrosis or perforation occurred in any animal. Fibrous wall thickness tended to decrease macroscopically and microscopically in a triamcinolone dose-dependent manner (control vs. steroid 2 × group: 773.1 vs. 468.5 µm, P = 0.037). Thickness also decreased over time in the steroid 2 × group (3 days vs. 4 weeks: 907.9 vs. 468.5 µm, P = 0.025). Blood parameters tended to improve after stent insertion. In a porcine BBS model, steroid-eluting FCSEMS showed potential as a safe and effective treatment modality to reduce fibrotic tissue. Studies are required to confirm their safety and efficacy in humans with refractory BBS.

Simultaneous Side-by-Side Bilateral Placement of Braided-Type Metal Stents Using a 5.9F Delivery System for Unresectable Malignant Hilar Biliary Obstruction: A Preliminary Feasibility Study.

Introduction Side-by-side (SBS) bilateral placement of self-expandable metal stents (SEMSs) is limited by technical difficulties in cases of malignant hilar bile duct obstruction (MHBO). Recently, a braided SEMS with a 5.9 F ultra-thin introducer was developed that enables simultaneous bilateral stenting.Materials and Methods This preliminary study was undertaken to determine the feasibility, safety, and effectiveness of SBS simultaneous bilateral stenting using braided SEMSs and a 5.9 F introducer for MHBO management. We reviewed 8 patients of medical reports who were performed simultaneous SBS placement of SEMSs due to MHBO between January 2016 and January 2018.Results Both of technical and clinical success rates were 100% (8/8), and success rate of stent distal end alignment was also 100%. None of early procedure-related adverse events were detected in 30 days after the stent insertion. Median duration of stent patency was 300 days (95% Cl, 280-726.9), and median survival was 229 days (range, 128-728).Conclusions: Simultaneous SBS stent placement using novel braided metal stents was found to be feasible in patients with MHBO. Prospective well-designed clinical studies are needed to certify the efficacy of the stenting technique for MHBO.

Collective bacterial disinfection by opto-chemical treatment on mature biofilm in clinical endoscope.

The present study proposes an innovative opto-chemical treatment using a basket-integrated optical device (BIOD) to disinfect mature bacterial biofilm on endoscope channels. A BIOD was designed to position an optical diffuser on the central axis of an endoscope channel and to distribute laser light concentrically to the bacterial biofilm on the channel surface. To apply thermal damage and oxidative stress to the bacterial biofilm, a low concentration of a crosslinking agent (glutaraldehyde ~0.5%) was combined with 808 nm infrared (IR) and 405 nm blue (BL) laser lights. The applied irradiances of IR and BL were 10 W/cm2 and 1.6 W/cm2 for Teflon channel model and 20 W/cm2 and 3.2 W/cm2 for a clinical model, respectively. Individual irradiation of either IR or BL for 180 s induced the maximum temperatures of 62 ± 2 °C and 53 ± 3 °C on the biofilm, respectively. The simultaneous opto-chemical treatment reduced a significant population of the bacterial biofilms (7.5-log10 for Staphylococcus aureus and 7.1-log10 for Pseudomonas aeruginosa), which were 2.9-fold and 3.9-fold higher than that of the standard treatment with 2% glutaraldehyde (GA) solution, respectively. The proposed opto-chemical disinfection method can help reduce multi-drug resistant bacteria and prevent cross-infection during the clinical usage of a flexible endoscope.

Endoscopic ultrasound (EUS)-guided cylindrical interstitial laser ablation (CILA) on in vivo porcine pancreas.

This study aims to demonstrate the feasibility of cylindrical interstitial laser ablation (CILA) in porcine pancreatic tissue to develop a EUS-guided PC ablation technique with enhanced safety. A diffusing applicator created a uniformly symmetrical laser ablation in pancreatic tissue. Ex vivo tests presented that both ablation thickness and volume increased linearly with the applied power (R2 = 0.96 and 0.90, respectively) without carbonization and fiber degradation. The numerical simulations matched well with the experimental results in terms of temperature development and thermal damage (deviation of ≤ 15%). In vivo tests with EUS confirmed easy insertion and high durability of the diffusing applicator. EUS-guided CILA warranted a feasible therapeutic capacity of ablating in vivo pancreatic tissue. The proposed EUS-guided CILA can be a feasible therapeutic approach to treat PC with predictable thermal ablation and enhanced safety.

Primary Needle-Knife Sphincterotomy for Biliary Access in Patients at High Risk of Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis.

METHODS: Forty patients with one or more risk factors for PEP were prospectively enrolled between June 2018 and November 2019. The cannulation was conducted in all patients using NKS as the primary cannulation technique. Success rate of biliary cannulation, biliary cannulation time, and adverse event rate were assessed. RESULTS: Of the 40 patients enrolled, 34 patients underwent primary NKS after the screening. Nine patients had 1 risk factor for PEP, 7 had 2, 8 had 3, 7 had 4, and 3 had 5. The success rate of biliary access by NKS was 94.1% (32/34). The median procedure time for NKS and the total procedure time for stone removal or biliary drainage were 4.1 minutes (range, 0.5-25.2) and 11.3 minutes (range, 3.8-40.4), respectively. Adverse events occurred in two patients (minor bleeding, n = 1; hyperamylasemia, n = 1). No patient experienced PEP or perforation. CONCLUSION: NKS might be feasible as a primary cannulation procedure in patients at high risk of PEP. This trial is registered with KCT0004886 (03/06/2018).

[Large Animal Models in Pancreas and Biliary Disease].

Rodent models, which have played important roles in preclinical research of pancreas and biliary diseases, have some limitations to translating data from rodent models to human diseases. Large animal models have recently been developed to overcome these limitations and perform translational research of medical devices and drugs in pancreas and biliary diseases. Preclinical studies using large animal models are necessary before clinical application, especially for the research and development of equipment, instrumentation, and techniques in pancreato-biliary diseases. As long as the endoscope used in humans can enter an organ, there appears to be no limitation in terms of species or organ for endoscopic experiments of large animal models. Investigators have mainly used swine for pancreas and biliary endoscopic experiments. Until now, unique swine models that investigators have been established include the normal bile duct model, bile duct dilation model, bile duct dilation+direct peroral cholangioscopy model, benign biliary stricture model, hilar biliary obstruction model, and acute pancreatitis (post-ERCP pancreatitis) model. Many preclinical studies have been performed using these established endoscopy-based large animal models to develop novel medical devices. Furthermore, porcine pancreatic cancer models induced by a transgenic or orthotopic method are currently under development. These models appear to be available for general use in the future and will have multiple potential preclinical and clinical applications.

Exosome-mediated diagnosis of pancreatic cancer using lectin-conjugated nanoparticles bound to selective glycans.

The unique profile of upregulated glycosylation in metastatic cancer cells may form the basis for the development of new biomarkers for the targeting and diagnosis of specific cancers. This study introduces a pancreatic cancer cell-derived exosome detection technology, which is based on the specific binding of lectins to distinctive glycan profiles on the surface of exosomes. Lectins with a high and specific affinity for sialic acid or fucose were attached to bifunctional Janus nanoparticles (JNPs), which facilitated interactions with pancreatic cancer cell-derived exosomes in a microfluidic device. Here, we show that pancreatic cancer cell-derived exosomes from two cell lines and plasma samples collected from patients diagnosed with pancreatic cancer were successfully captured on the lectin-conjugated JNPs with affinities that were comparable to those of CA19-9, a conventional antibody. In addition, exosome detection using our platform could differentiate between metastatic and nonmetastatic pancreatic cancer cells. This study opens the possibility to achieve a new early diagnosis marker based on the glycan properties of pancreatic cancer cell-derived exosomes.

Clinical efficacy of high-flow nasal oxygen in patients undergoing ERCP under sedation.

Hypoxemia can occur during endoscopic retrograde cholangiography (ERCP) and it is difficult to achieve adequate ventilation with the prone position. High-flow nasal oxygen (HFNO) has been recommended to be more effectively help ventilation than conventional low flow oxygen. The aim of this study was to evaluate the effect of HFNO during sedated ERCP and to identify predictors of desaturation during ERCP. The investigated variables were age, gender, American Society of Anesthesiologists classes (ASA), duration of exam, and sedative used for midazolam or/and propofol of 262 patients with sedated ERCP. The differences between categorical and continuous variables were analyzed using the Student's t test and the chi-square test. Desaturation (SpO2 ≤ 90%) occurred in 9(3.4%) patients among 262 patients during sedated ERCP. The variables found to predict desaturation were older age (p < 0.01), higher sedation dose for midazolam or propofol (p < 0.01), and use of midazolam (p < 0.01). Desaturation rate was lower during sedated ERCP with HFNO compared to the preliminary study with conventional low flow nasal oxygen. Patients with older age, higher sedation dose, or the use of midazolam might require close monitoring for desaturation and hypoventilation by nursing staff. The study shows the use of high-flow nasal oxygen reduces the incidence of desaturation during ERCP.

The use of a 532-nm laser fitted with a balloon and a cylindrical light diffuser to treat benign biliary stricture: a pilot study.

Endoscopic management of benign biliary stricture (BBS) remains challenging. Stenting is currently used for BBS management, but refractory BBS remains problematic. The aim of this study was to assess the safety and feasibility of a dilation balloon-equipped cylindrical light diffuser for BBS in a large animal model. A total of seven mini-pigs were used in the current study. Laser settings were chosen based on the findings of a previous animal study. Five animals were used in a preliminary study to establish process conditions. BBSs were created in the common bile ducts of the other two animals by intraductal radiofrequency ablation (RFA) via endoscopic retrograde cholangiography (ERC). At 4 weeks post-RFA, laser ablation was performed using a customized balloon-equipped cylindrical diffuser at 10 W for 10 s while maintaining balloon inflation for 10 s at 5 atm. A follow-up ERC was performed at 4 weeks post-laser ablation and the animals were sacrificed for histologic evaluation. BBS was observed in all animals by ERC at 4 weeks post-RFA. The mean bile duct stricture diameter in the two animals as determined by ERC was 0.8 mm. Laser ablations were performed without technical difficulty and no adverse event was encountered. At 4 weeks post-laser ablation, mean biliary stricture diameter had dilated to 1.6 mm on cholangiographic finding. On histologic examination, inflammatory cell infiltration in lamina propria and dense collagen deposition were observed, but there was no evidence of bile duct perforation. The devised balloon-equipped cylindrical laser light diffuser appears to be safe and feasible for the treatment of BBS. However, further studies and modifications are required before it can be applied clinically as a monotherapy.

A novel electrocautery-enhanced delivery system for one-step endoscopic ultrasound-guided drainage of the gallbladder and bile duct using a lumen-apposing metal stent: a feasibility study.

BACKGROUND: The use of a lumen-apposing metal stent (LAMS) capable of one-step endoscopic ultrasound-guided transmural drainage (EUS-TD) can increase the effectiveness of the procedure. We evaluated the newly developed electrocautery-enhanced (EC) delivery system with a LAMS for one-step EUS-guided gallbladder drainage (EUS-GBD) or choledochoduodenostomy (EUS-CDS). METHODS: In the animal experiment, an EC-LAMS was advanced into the gallbladder without prior tract dilation in four pigs. A conventional LAMS was inserted in another four pigs as a control group. After the animal experiment, 17 patients underwent EUS-TD using the EC-LAMS (EUS-GBD in 10 patients, EUS-CDS in 7). The primary outcome was the technical success rate. RESULTS: In the animal study, the mean procedure time was significantly shorter in the EC-LAMS group than in the conventional LAMS group. In the human study, the overall technical success rate was 94.1 %, with one EUS-GBD failure. The clinical success rate was 100 %. The overall adverse event rate was 17.6 %. CONCLUSIONS: One-step EUS-GBD or EUS-CDS using the novel EC-LAMS is a feasible approach that achieves a high success rate and maintains safety.