Search

Background and Aims Recently, a newly designed lumen-apposing metal stent (LAMS) with a conventional delivery system was developed. The purpose of this study was to evaluate the effectiveness and safety of a newly designed LAMS for EUS-guided drainage to treat symptomatic pancreatic pseudocysts. Methods This prospective multicenter cohort study included 34 patients with symptomatic pancreatic pseudocysts from 2016 to 2017. The patients underwent EUS-guided drainage with the newly designed LAMS (Niti-S SPAXUS; Taewoong Medical Co, Ltd, Ilsan, South Korea). Effectiveness outcome measurements included technical success rate, clinical success rate, successful stent removal rate, and procedural time. Safety outcome measurements included procedure and/or stent-related adverse events (AEs) and overall AEs. Patients were prospectively followed, and consecutive data were collected at discharge, at stent removal, and 20 days after stent removal. Results Thirty-four patients (mean age 51.7 ± 13.3 years, 26 men) were enrolled. The mean pseudocyst size was 9.23 ± 3.54 cm. The technical success rate was 97.1% (33/34). The clinical success rate was 94.1% (32/34). All stents were successfully removed. The mean procedural time from needle puncture to stent deployment was 10.3 ± 5.7 minutes. Four patients (11.8%) experienced procedure and/or stent-related AEs, including stent maldeployment (n = 1) and pseudocyst infection (n = 3). All patients completely recovered from the AEs. Bleeding caused by the stent or buried LAMS syndrome was not observed. No unplanned endoscopic procedures were required. Conclusions This study showed that EUS-guided drainage using the newly designed LAMS is technically feasible and effective for the treatment of symptomatic pancreatic pseudocysts. (Clinical trial registration number: NCT02730663.)

Background and study aims The aim of the current study was to review the outcomes of a large-scale international registry on endoscopic ultrasound-guided gallbladder drainage (EGBD) that encompasses different stent systems in patients who are at high-risk for cholecystectomy. Patients and methods This was a retrospective international multicenter registry on EGBD created by 13 institutions around the world. Consecutive patients who received EGBD for several indications were included. Outcomes include technical and clinical success, unplanned procedural events (UPE), adverse events (AEs), mortality, recurrent cholecystitis and learning curve of the procedure. Results Between June 2011 and November 2017, 379 patients were recruited to the study. Technical and clinical success were achieved in 95.3 % and 90.8 % of the patients, respectively. The 30-day AE rate was 15.3 % and 30-day mortality was 9.2 %. UPEs were significantly more common in patients with EGBD performed for conversion of cholecystostomy and symptomatic gallstones (P Conclusion EGBD was associated with high success rates in this large-scale study. EGBD performed for indications other than acute cholecystitis was associated with higher UPEs. The number of cases required to gain competency with the technique by experienced interventional endosonographers was 25 procedures.

The effects of applying an inner coating of nanosized gadolinium-doped ceria, Gd0.1Ce0.9O2-δ, sols on the porous NiFe-metal support for solid oxide fuel cell application are investigated. The GDC nanosols are synthesized by a sol-gel method using metal-alkoxide precursors and the Ni/Fe ratio of metal support is optimized. Field-emission transmission electron microscope reveals that the synthesized sols have particle size of 2–3 nm. Metal supports based on alloys composed of Ni and Fe are used in this work, and the ratio of Ni/Fe is optimised. In case of Ni/Fe ratio of 9:1, high porosity (≥ 57%) metal supports are obtained and the physico-chemical compatibility between the NiFe-metal supports and the Ni-GDC anodes is improved. The I-V results demonstrate a remarkable improvement in the power density of the GDC nanosol-coated button cell (677 mW cm−2) compared to that of the uncoated cell (437 mW cm−2) at 650 °C. The total area specific resistance after the coating GDC nanosols significantly decrease from 0.226 Ω cm2 to 0.125 Ω cm2. These results reflect that GDC nanosols play an important role in reducing the resistances due to the effective expansion of the triple phase boundary and the improved connectivity of the ionically conductive phase.

Background Although endoscopic retrograde cholangiopancreatography (ERCP) is a first-line diagnostic modality for suspected malignant biliary stricture (MBS), the diagnostic yield of ERCP-based tissue sampling is insufficient. Peroral cholangioscopy-guided forceps biopsy (POC-FB) and endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) are evolving as reliable diagnostic procedures for inconclusive MBS. This study aimed to evaluate the usefulness of a diagnostic approach using POC-FB or EUS-FNAB according to the stricture location in patients with suspected MBS. Methods Consecutive patients diagnosed with suspected MBS with obstructive jaundice and/or cholangitis were enrolled prospectively. ERCP with transpapillary forceps biopsy (TPB) was performed initially. When malignancy was not confirmed by TPB, POC-FB using a SpyGlass direct visualization system or direct POC using an ultraslim endoscope was performed for proximal strictures, and EUS-FNAB was performed for distal strictures as a follow-up biopsy. Results Among a total of 181 patients, initial TPB showed malignancy in 122 patients, and the diagnostic accuracy of initial TPB was 71.8 % (95 % confidence interval [CI] 65.3 % – 78.4 %]. Of the 59 patients in whom TPB was negative for malignancy, 32 had proximal biliary strictures and underwent successful POC. The remaining 27 patients had distal strictures and underwent successful EUS-FNAB. The accuracy of malignancy detection using POC-FB for proximal biliary strictures and EUS-FNAB for distal biliary strictures was 93.6 % (95 %CI 84.9 %−100 %) and 96.3 % (95 %CI 89.2 %−100 %), respectively. The overall diagnostic accuracy for the combination of TPB with either POC-FB for proximal strictures and EUS-FNAB for distal strictures was 98.3 % (95 %CI 95.9 %−100 %) and 98.4 % (95 %CI 95.3 %−100 %), respectively. Conclusions An approach using POC-FB or EUS-FNAB according to the stricture location may be useful in the diagnosis of suspected MBS.

Background/Aims In suspected malignant biliary strictures (MBSs), the diagnostic yield of endoscopic retrograde cholangiopancreatography (ERCP)-based tissue sampling is limited. Transpapillary forceps biopsy (TPB) under intraductal ultrasonography (IDUS) guidance is expected to improve the diagnostic accuracy in patients with indeterminate biliary strictures. We evaluated the usefulness of IDUS-guided TPB in patients with suspected MBS. Methods Consecutive patients with suspected MBS were prospectively enrolled in the study. ERCP with IDUS was performed in all patients. Both conventional TPB and IDUS-guided TPB on fluoroscopy were performed in each patient. The primary outcome was the diagnostic accuracy of conventional TPB and IDUS-guided TPB. Results The technical success rate of IDUS-guided TPB was 97.0% (65/67 patients). Of these 65 patients, the final diagnosis was malignancy in 61 patients (93.8%). On IDUS, the most common finding of IDUS was an intraductal infiltrating lesion in 29 patients (47.5%). The overall diagnostic accuracy was significantly higher using IDUS-guided TPB than that using conventional TPB (90.8% vs 76.9%, p=0.027). According to the subgroup analysis based on the tumor morphology, IDUS-guided TPB had a significantly higher cancer detection rate than conventional TPB for intraductal infiltrating lesions (89.6% vs 65.5%, p=0.028). Conclusions IDUS-guided TPB appears to improve the accuracy of histological diagnosis in patients with MBS.

The effects of a Cu-based additive and nano-Gd-doped ceria (GDC) sol on the sintering temperature for the construction of solid oxide cells (SOCs) were investigated. A GDC buffer layer with 0.25–2 mol% CuO as a sintering aid was prepared by reacting GDC powder and a CuN2O6 solution, followed by heating at 600 °C. The sintering of the CuO-added GDC powder was optimized by investigating linear shrinkage, microstructure, grain size, ionic conductivity, and activation energy at temperatures ranging from 1000 to 1400 °C. The sintering temperature of the CuO–GDC buffer layer was decreased from 1400 °C to 1100 °C by adding the CuO sintering aid at levels exceeding 0.25 mol%. The ionic conductivity of the CuO–GDC electrolyte was maximized at 0.5 mol% CuO. However, the addition of CuO did not significantly affect the activation energy of the GDC buffer layer. Buffer layers with CuO-added GDC or nano-GDC sol-infiltrated GDC were fabricated and tested in co-sintering (1050 °C, air) with La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF). In addition, SOC tests were performed using button cells (active area: 1 cm2) and five-cell (active area: 30 cm2/cell) stacks. The button cell exhibited the maximum power density of 0.89 W cm−2 in solid oxide fuel cell (SOFC) mode. The stack demonstrated more than 1000 h of operation stability in solid oxide electrolysis cell (SOEC) mode (decay rate: 0.004%/kh).

Background and Aims The efficacy of palliative biliary drainage by using bilateral or unilateral self-expandable metal stents (SEMSs) for a malignant hilar biliary stricture (MHS) remains controversial. This prospective, randomized, multicenter study investigated whether bilateral drainage by using SEMSs is superior to unilateral drainage in patients with inoperable MHSs. Methods Patients with inoperable high-grade MHSs who underwent palliative endoscopic insertion of bilateral or unilateral SEMSs were enrolled. The main outcome measurements were the rate of primary reintervention for malfunction after successful placement of SEMSs, stent patency, technical and clinical success rates, adverse events, and survival duration. Results A total of 133 pathology-diagnosed patients were randomized to the bilateral group (n = 67) or the unilateral group (n = 66). The primary technical success rates were 95.5% (64/67) and 100% (66/66) in the bilateral and unilateral groups, respectively ( P = .244). The clinical success rates were 95.3% (61/64) and 84.9% (56/66), respectively ( P = .047). The primary reintervention rates based on the per-protocol analysis were 42.6% (26/61) in the bilateral group and 60.3% (38/63) in the unilateral group ( P = .049). The median cumulative stent patency duration was 252 days in the bilateral group and 139 days in the unilateral group. The risk of stent patency failure was significantly higher in the unilateral group (log-rank test; P P Conclusions Unilateral and bilateral drainage strategies by using SEMSs had similar technical success rates, but bilateral drainage resulted in fewer reinterventions and more durable stent patency in patients with inoperable high-grade MHSs. (Clinical trial registration number: NCT02166970.)

Sc-substituted La 0.6 Sr 0.4 FeO 3-δ (LSFSc) has been synthesized for utilization as an integrated ceramic interconnector of tubular-solid oxide cells (SOCs). Redox stability and electric conductivity of LSFSc were improved by optimizing the scandium (Sc) doping concentration, the pH of the synthetic solutions and the calcination temperature of the organic precursors. The crystalline phases of LSFSc were stable when the pH of the synthetic solution was below 2 and the calcination temperature was over 1200 °C. As the Sc concentration increased, redox stability was improved while the electrical conductivity decreased. To consider the trade-off relationship between electrical conductivity and phase stability, La 0.6 Sr 0.4 Fe 0.9 Sc 0.1 O 3-δ can be considered as one of the stable compositions for an integrated ceramic interconnector of tubular-SOCs.

Background/Aims Treatment for cholangitis without common bile duct (CBD) stones has not been established in patients with gallstones. We investigated the usefulness of endoscopic biliary drainage (EBD) without endoscopic sphincterotomy (EST) in patients diagnosed with gallstones and cholangitis without CBD stones by endoscopic retrograde cholangiopancreatography (ERCP) and intraductal ultrasonography (IDUS). Methods EBD using 5F plastic stents without EST was performed prospectively in patients with gallstones and cholangitis if CBD stones were not diagnosed by ERCP and IDUS. After ERCP, all patients underwent laparoscopic cholecystectomy. The primary outcomes were clinical and technical success. The secondary outcomes were recurrence rate of biliary events and procedure-related adverse events. Results Among 187 patients with gallstones and cholangitis, 27 patients without CBD stones according to ERCP and IDUS received EBD using 5F plastic stents without EST. The stents were maintained in all patients until laparoscopic cholecystectomy, and recurrence of cholangitis was not observed. After cholecystectomy, the stents were removed spontaneously in 12 patients and endoscopically in 15 patients. Recurrence of CBD stones was not detected during the follow-up period (median, 421 days). Conclusions EBD using 5F plastic stents without EST may be safe and effective for the management of cholangitis accompanied by gallstones in patients without CBD stones according to ERCP and IDUS.

Background and Aim As society ages, the need for endoscopic retrograde cholangiopancreatography (ERCP) is increasing. This prospective comparative study evaluated the safety and efficacy of midazolam- versus propofol-based sedations by non-anesthesiologists during therapeutic ERCP in patients over 80 years of age. Methods A total of 100 patients over 80 years of age who required therapeutic ERCP were enrolled and randomly received midazolam + fentanyl (MF group) or propofol + fentanyl (PF group) sedation. Endoscopic sedation was titrated to a moderate level and carried out by trained registered nurses. Main outcome measurements were sedation safety in terms of cardiopulmonary components and efficacy measured on a 10-point visual analogue scale (VAS). Results Regarding safety, hypoxia occurred in seven (14%) in the MF group and in eight patients (16%) in the PF group (P = 0.779). Increased O2 supply was more frequent in the PF group (32% vs 42%), albeit not significantly so. There were no differences in the frequency of hypotension, bradycardia or tachycardia between the two groups. Mean VAS score for overall satisfaction with sedation by patients, endoscopists, and nurses and the scores for pain during the procedures were not different between the two groups. There was no significant difference in the procedure outcomes or rate of ERCP-related complications. Conclusions There were no significant differences of safety and efficacy between midazolam- and propofol-based sedation in patients over 80 years of age. Increased O2 supply was more frequent in the propofol group, but the prevalence of hypoxia did not differ significantly.

In malignant biliary stricture (MBS), the diagnostic accuracy of ERCP‐based tissue sampling is insufficient. EUS‐guided fine needle aspiration biopsy (EUS‐FNAB) is emerging as a reliable diagnostic procedure. This study aimed to evaluate the usefulness of a diagnostic approach using ERCP‐guided transpapillary forceps biopsy (TPB) or EUS‐FNAB according to the characteristics of suspected MBS. Consecutive patients diagnosed with suspected MBS with obstructive jaundice and/or cholangitis were enrolled prospectively. ERCP with intraductal ultrasonography (IDUS) and TPB were performed as initial diagnostic procedures. Based on the results of imaging studies and IDUS, all MBS were classified as extrinsic or intrinsic type. If the malignancy was not confirmed by TPB, EUS‐FNAB for extrinsic type or second TPB for intrinsic type was performed. Among a total of 178 patients, intrinsic and extrinsic types were detected in 88 and 90 patients, respectively. The diagnostic accuracy of first TPB was significantly higher in the intrinsic than in the extrinsic type (81.8% vs. 67.8, P = 0.023). In 33 patients with extrinsic type and negative for malignancy on first TPB, the diagnostic accuracy of EUS‐FNAB was 90.9%. In 19 patients with intrinsic type and negative for malignancy on first TPB, the diagnostic accuracy of second TPB was 84.2%. The diagnostic accuracies of the combination of initial TPB with EUS‐FNAB and second TPB were 96.7% and 96.6%, respectively. A diagnostic approach using EUS‐FNAB or TPB according to the origin of MBS is considered effective to improve the diagnostic accuracy of MBS with negative for malignancy on first TPB. (Clinical trial registration number: UMIN000016886).

Background/Aims Controversy still exists regarding the benefits of covered self-expandable metal stents (SEMSs) compared to uncovered SEMSs. We aimed to compare the patency and stent-related adverse events of partially covered SEMSs (PC-SEMSs) and uncovered SEMSs in unresectable malignant distal biliary obstruction. Methods A total of 134 patients who received a PC-SEMS or uncovered SEMS for palliation of unresectable malignant distal biliary obstruction were reviewed retrospectively. The main outcome measures were stent patency, stent-related adverse events, and overall survival. Results The median stent patency was 118 days (range, 3 to 802 days) with PC-SEMSs and 105 days (range, 2 to 485 days) with uncovered SEMSs (p=0.718). The overall endoscopic revision rate due to stent dysfunction was 36.6% (26/71) with PC-SEMSs and 36.5% (23/63) with uncovered SEMSs (p=0.589). Tumor ingrowth was more frequent with uncovered SEMSs (4.2% vs 19.1%, p=0.013), but migration was more frequent with PC-SEMSs (11.2% vs 1.5%, p=0.04). The incidence of stent-related adverse events was 2.8% (2/71) with PC-SEMSs and 9.5% (6/63) with uncovered SEMSs (p=0.224). The median overall survival was 166 days with PC-SEMSs and 168 days with uncovered SEMSs (p=0.189). Conclusions Compared to uncovered SEMSs, PC-SEMSs did not prolong stent patency in unresectable malignant distal biliary obstruction. Stent migration was more frequent with PC-SEMSs. However, tumor ingrowth was less frequent with PC-SEMSs compared to uncovered SEMSs.

Introduction Chemo-responsiveness in pancreatic cancer is known to be dependent on fibrosis and vascularity. The purpose of this study was to assess vascular enhancement in advanced pancreatic adenocarcinoma with or without liver metastasis in computed tomography (CT) and to analyze the correlation between enhancement patterns and chemo-responsiveness. Methods Patients were assigned to either a responder group (partial response or stable disease) or a non-responder group (progressive disease) according to chemo-responsiveness assessed by CT before and after gemcitabine-based chemotherapy. Hounsefield unit (HU) was measured in pancreatic mass and the largest metastatic liver mass using region of interest (ROI). HU differences (ΔHU) between arterial and pre-contrast phase were calculated. Results Of the 101 study subjects, 78(77.2%) were assigned to the pancreas responder group {mean ΔHU (±SD), 36.7(±21.6)} and 23(22.8%) to the pancreas non-responder group {mean ΔHU (±SD), 20.6(±9.9)} (p = 0.001 for ΔHUs). Of the 46 study subjects with liver metastasis, 25(54.3%) were assigned to the liver metastasis responder group {mean ΔHU (±SD), 36.9(±21.0} and 21(45.7%) to the liver metastasis non-responder group {mean ΔHU (±SD), 17.1 (±24.0)}, (p = 0.005 for ΔHUs). Conclusion CT determined mass vascular enhancement patterns may predict chemoresponse in advanced pancreatic cancer.

Background and Aim It can be difficult to identify the cause of an enlarged ampulla of Vater (AOV). This study evaluated the accuracy of wire-guided intraduodenal ultrasonography (US) for the differential diagnosis of an enlarged AOV during endoscopic retrograde cholangiopancreatography (ERCP). Patients and Methods Thirty-four patients with enlarged AOVs of unknown cause identified on imaging studies or endoscopic observations underwent wire-guided intraduodenal US using a catheter probe. Results The final diagnoses were malignant or premalignant tumors in 10 patients (29.4%), stones in nine patients (26.5%), inflammation in 14 patients (41.2%), and cyst in one patient (2.9%). The overall diagnostic accuracy of intraduodenal US for enlarged AOVs was 91.2%. The diagnostic accuracies of stones, inflammation, and AOV tumors were 100.0%, 94.1%, and 91.1%, respectively. Conclusions Wire-guided intraduodenal US using a catheter probe is readily applicable during ERCP and may be useful in the differential diagnosis of enlarged ampullary lesions.

Background and Aim KRAS mutation analysis may provide ancillary diagnostic yield in an endoscopic ultrasound (EUS)-guided histopathological evaluation. We evaluated the clinical impact of KRAS mutation analysis with cytological and histological evaluations in EUS-guided tissue sampling, using a core biopsy needle for solid liver masses. Methods EUS-guided fine needle biopsy (EUS-FNB) using a core biopsy needle was performed in patients with primary or metastatic liver masses that were suspected malignancies. KRAS mutations were analyzed in all specimens obtained. The peptide nucleic acid (PNA)-mediated polymerase chain reaction (PCR) clamping method was compared with a next-generation sequencing (NGS) method for detecting KRAS mutations. Results EUS-FNB with a core biopsy needle was performed in 28 patients with solid liver masses located in the liver's left lobe. The diagnostic accuracies for malignancy of on-site cytology, cytology using Papanicolaou staining, and histology including immunohistochemical stains were 82.1%, 85.7%, and 89.3%, respectively. KRAS gene mutations were observed in 14.3% of patients by the PNA-PCR clamping method. The NGS method detected more KRAS mutations than the PNA-PCR clamping method: in 25% of patients. Adding the results of KRAS mutation analysis to the cytohistopathological evaluation, the overall diagnostic accuracy of EUS-guided tissue sampling was 96.4%. Conclusions EUS-guided tissue sampling for solid liver masses in the left lobe provided high diagnostic accuracy from cytological and histological evaluations. KRAS mutation analysis provided additional diagnostic yield in patients with inconclusive cytohistopathological results from EUS-guided tissue sampling. The NGS method detected additional KRAS mutations in patients with negative PNA-mediated PCR clamping test results.

Currently available peroral cholangioscopy (POC) is a duodenoscopy-assisted procedure that does not involve directly inserting an endoscope into the biliary tree. A prototype multibending (MB) ultra-slim endoscope has been developed as a dedicated cholangioscope to overcome the technical difficulties of direct POC. In this study, we evaluated the efficacy of the new MB ultra-slim endoscope compared with a conventional ultra-slim endoscope for free-hand insertion of an endoscope into the bile duct for direct POC without the assistance of accessories.Ninety-two patients with biliary disease requiring diagnostic and/or therapeutic direct POC were assigned randomly to groups examined using an MB ultra-slim endoscope (MB group, n=46) versus a conventional ultra-slim endoscope (conventional group, n=46). The primary outcome was the technical success of free-hand insertion of the endoscope during direct POC, defined as successful insertion of the endoscope through the ampulla of Vater and advancement of the endoscope up to the bifurcation or to the obstructed segment of the biliary tree without any accessories within 15 minutes.Free-hand biliary insertion of the endoscope for direct POC was technically successful in 41 patients (89.1%) in the MB group, which was significantly higher than the rate (14 patients, 30.4%) in the conventional group (P .001). The procedure time (mean ± standard deviation) of direct POC using free-hand biliary insertion of the endoscope was significantly shorter in the MB group than in the conventional group (3.2 ± 1.8 vs 6.0 ± 3.0 minutes, P = .004). Adverse events were observed in 3 patients (6.5%) in the MB group and 2 patients (4.3%) in the conventional group (P = .500), all of whom were treated conservatively. The technical success rates of the diagnostic or therapeutic intervention were not significantly different between the 2 groups in patients undergoing successful direct POC.Free-hand biliary insertion of the MB ultra-slim endoscope showed a high technical success rate without severe adverse events and effectively decreased procedure time compared with a conventional ultra-slim endoscope. Direct POC using the MB ultra-slim endoscope can be used for novel diagnostic and therapeutic procedures of the biliary tree without the assistance of another endoscope or accessory. (Clinical trial registration number: NCT02189421.).

Background A novel self-approximating lumen-apposing metallic stent (LAMS; Niti-S Spaxus, Taewoong Medical, Gyeonggi-do, Korea) has recently become available. The aim of the present study was to evaluate the outcomes for drainage of pancreatic fluid collections (PFC). Methods This was a prospective international multicentered study conducted in six high-volume institutions across Asia. Consecutive patients suffering from pancreatic pseudocyst or walled-off pancreatic necrosis (WOPN) requiring endoscopic ultrasonography-guided drainage were recruited. Outcomes included technical and clinical success, adverse events, procedural events, interventions through the stent and recurrence rates. Results Between August 2016 and November 2017, 59 patients were recruited to this study. Thirty-nine patients (66.1%) had WOPN and mean (SD) size of PFC was 11.5 (5.1) cm. Technical and clinical success rates were 100%. Mean (SD) procedural time was 35.0 (17.2) minutes. Sixteen-millimeter stents were used in 66.1% of the patients. Fifty-four sessions of necrosectomy were carried out with the stent in situ in 17 patients. Stent-related adverse event (AE) rate was 6.8%. Three patients (5.1%) suffered from bleeding after stenting and one required angiographic embolization. Two patients (3.4%) suffered from recurrence during a mean (SD) follow-up time of 325.6 (355.5) days. There were no differences in outcomes between those with pseudocysts or WOPN except for the duration of hospital stay (P = 0.012). Conclusion Use of a self-approximating LAMS for drainage of PFC was safe and effective. Endoscopic necrosectomy could be carried out through the stent with ease. The device was associated with a low rate of stent-related AE.

Objective Acquiring adequate tissue for immunohistochemical (IHC) analysis is important in the differential diagnosis of subepithelial tumors (SETs). In this study, we aimed to compare the diagnostic yield based on IHC analysis between endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and EUS-guided fine needle biopsy (EUS-FNB) after on-site cytological evaluation for cellularity in gastric SETs. Methods In 22 patients with gastric SETs, EUS-guided tissue sampling was performed on the same SET in a randomized sequence, with EUS-FNA followed by EUS-FNB, or vice versa. After on-site cytological evaluation for cellularity, the cytological and histological examinations were performed. Results There was a significant difference in the median number of needle passes to obtain adequate cellularity in the on-site cytological evaluation (2.0 for EUS-FNA vs 1.0 for EUS-FNB, P = 0.008). The proportion of adequate cellularity on the first needle pass was significantly higher in the EUS-FNB than in the EUS-FNA group (68.2% vs 31.8%, P = 0.034). However, diagnosis based on IHC examination was established in 15 (68.2%) and 18 (81.8%) cases by EUS-FNA and EUS-FNB, respectively (P = 0.488). Conclusions EUS-FNB decreases the number of needle passes to obtain adequate cellularity and yields a higher proportion of adequate cellularity during the first needle pass compared with EUS-FNA in gastric SETs. However, there was no significant difference in diagnostic yield with IHC stain between the two procedures after on-site cytological evaluation for adequate cellularity.

Background and study aim: The nonflared ends of fully covered, self-expandable, metal stents (FCSEMSs) may minimize stent-induced ductal injury. Suprapapillary intraductal placement of nonflared FCSEMSs for malignant biliary stricture might reduce duodenobiliary reflux and pancreatitis. The aim of this study was to evaluate the efficacy of a newly modified, nonflared FCSEMS for intraductal placement in patients with malignant biliary stricture. Patients and methods: A total of 51 patients with nonhilar, extrahepatic, malignant biliary stricture were enrolled prospectively. The nonflared FCSEMS is 12 mm in diameter, and has a central saddle and a distal lasso of 7 cm in length. An FCSEMS was placed above the papilla in all patients, with the central saddle positioned at the stricture to prevent stent migration. Results: The technical and clinical success rates were 100 % and 98 %, respectively. Early adverse events occurred in one patient (2.0 %; mild pancreatitis). A total of 12 patients underwent surgery with curative intent, one of whom (8.3 %) experienced a postoperative adverse event. No stent migration occurred in any of the patients. Cholecystitis developed in one patient (2.0 %) as a late adverse event. Stent occlusion occurred in 44.7 % (17/38), and endoscopic removal of the stent was successful in 87.5 % of patients. The mean stent patency was 297 days (95 % confidence interval, 211 – 383). Conclusions: Intraductal placement of the nonflared FCSEMS, 12 mm in diameter, was feasible for the palliative and preoperative management of patients with malignant biliary stricture. Long-term follow-up and prospective comparative studies are needed to evaluate the usefulness of intraductal placement of this stent.

A reproducible in vivo swine model of bile duct dilation (BDD) was recently established and reported for the preclinical testing of newly developed biliary devices or endoscopic techniques. The aim of this study is to develop more advanced large animal model which is possible to direct examination of the biliary tree. Six mini pigs were prepared for the study. The BDD models were first made by closure of the ampulla of Vater in all swine. Then endoscopic papillary balloon dilation (EPBD) was performed in the animals. The feasibility of single-operator peroralcholangioscopy without assistance of accessories was evaluated using an ultra-slim upper endoscope in the animals. EPBD could be implemented using a dilation balloon catheter (10 ~ 13.5 mm) in all BDD models (6/6, 100%). The success rate of free-hand direct insertion of an ultra-slim endoscope into the common bile duct (CBD) was 100% (6/6), and access to the common hepatic duct with examination was possible using the direct peroralcholangioscopy in five animals (5/6, 83.3%). None of the animals died. In the cholangioscopic examination, a bile duct polyp and a benign biliary stricture occurred naturally, respectively, in two of six swine. An in vivo swine model of biliary dilatation-based direct peroralcholangioscopy was established. This novel animal model may be useful for the preclinical research of new materials or devices because direct visualization of the biliary tree is feasible. This article is protected by copyright. All rights reserved.

Background and Aim: A major concern about endoscopic snare papillectomy (ESP) is the risk of procedure-related pancreatitis. To maintain pancreatic duct access for stent placement after ESP, wire-guided ESP (WP) was introduced. The aim of the study was to compare post-procedure pancreatitis rates, the success rate of pancreatic stent insertion, and complete resection rates between WP and conventional ESP (CP) procedures. Methods: This was a multi-center, prospective, randomized pilot study. Forty-five patients with ampullary tumors were randomly assigned to a WP group (n = 22) or a CP group (n = 23). In the WP group, a guidewire was placed in the pancreatic duct prior to ESP. A 5-Fr pancreatic stent was passed over the guidewire and placed across the pancreatic duct orifice. Results: Complete resection was achieved in 20 patients (91%) in the WP group and 18 patients (78%) in the CP group (P = 0.414). A pancreatic stent was placed successfully in all patients in the WP group but in only 15 patients (65%) in the CP group (P = 0.004). Post-papillectomy pancreatitis occurred in four (18%) patients in the WP and three (13%) patients in the CP groups (P = 0.960). In the CP group, three of eight (37.5%) patients without stents developed pancreatitis compared with zero of 15 patients with stents (P = 0.032). Conclusions: The WP method is a useful technique used to insert a pancreatic stent after ESP, compared with CP. However, there was no significant difference in the post-procedure pancreatitis or complete resection rates between the two methods.

Concern regarding the safety and efficacy of therapeutic endoscopic retrograde cholangiopancreatography (ERCP) in elderly patients is increasing as a result of the aging society. However, there are limited data, especially in the super-aged elderly. This study aimed to evaluate the efficacy and safety of therapeutic ERCP in patients ≥80 years of age. Patients 80 years of age or older (n = 312) and younger than 65 years (n = 312) who underwent therapeutic ERCP from June 2006 to April 2014 were randomly selected and analyzed retrospectively. The main outcome measurements were therapeutic ERCP-related complications and clinical outcomes in the two groups. Choledocholithiasis combined with gallbladder stone was the most common indication for ERCP in both groups. Comorbid diseases (70.5 and 29.8 %, p

Gadolinia-doped ceria (GDC) sols were synthesized by the controlled hydrolysis and condensation of cerium(IV) isopropoxide with each gadolinia doping agent to make a dense GDC diffusion barrier for solid oxide electrolyte cells (SOECs) and intermediate-temperature solid oxide fuel cells (IT-SOFCs). The crystallinity of a GDC sol using gadolinium(III) isopropoxide as the doping agent was five to six times stronger than that when using gadolinium(III) nitrate hydrate as the doping agent. The GDC diffusion barrier was fully densified by infiltration of a GDC sol into a porous GDC structure under heat treatment at 1000 °C. The performance of a cell was highly improved from 0.60 W/cm 2 to 0.92 W/cm 2 at 750 °C by densification of the diffusion barrier. EIS results suggest that the improved performance is mainly due to the reduced ohmic resistance through the composite electrolyte (i.e., YSZ/GDC). Finally, the degradation of a single cell with a dense GDC was maintained below 1.72%/1000 h, which was lower than that of a cell with a porous GDC (7.69%/1000 h). Based on these results, it can be concluded that the enhancement of the performance and durability of a single cell with a dense GDC was the result of reduced ohmic resistance through the composite electrolyte.

Waste CdSe film electrodes can be recycled into useful films without sacrificing their photoelectrochemical performance. Cd2+ aqueous ions have been recovered from waste CdSe electrodes by soaking in minimal amount of HCl (10.0 M) at 80 °C for 60 min. The Se2− ions, converted into H2Se(g) by the acid, have been trapped in basic NaOH solution for further use. The recovered Cd2+ ions have been used to deposit new (recycled) CdSe film electrodes onto fluorine doped tin oxide films (FTO/Glass) using aqueous Na2SeSO3 solutions by two methods. Electrochemical deposition (ECD) has been performed using applied potential (−1.0 V vs Ag/AgCl). Chemical bath deposition (CBD) has been performed in a basic medium at 70 °C. Both ECD and CBD recycled films have been prepared using recovered Cd2+ solutions, whereas fresh films have been prepared using fresh solutions. In both cases, the recycled CdSe films do not show any inferior characteristics to the freshly prepared counterparts. Effects of annealing at 150 °C and cooling rate on physical and photoelectrochemical (PEC) characteristics have been studied for different CdSe film electrodes. In both recycled and fresh systems, the CBD film electrodes exhibit enhanced uniformity, compactness and photo-electrochemical (PEC) performance by annealing. Upon annealing, the recycled and fresh ECD films exhibit less film uniformity and compactness, and consequently lower PEC performance. In ECD and CBD films, fast cooling is advantageous over slow cooling. Conversion efficiency values of ~8% are observed for the CBD recycled pristine films once carefully annealed and quickly cooled. This is higher than literature values for pristine CdSe (~5%), TiO2/CdS/CdSe (~4%) film electrodes, and resembles that for Tl/CdSe0.65Te0.35 (~8) multi-layer systems. The results show the feasibility of recycling waste CdSe film electrodes.

Background and aims Catheter-based endobiliary radiofrequency ablation (RFA) is an endoscopic local treatment for patients with malignant biliary stricture (MBS). However, excessive heating of the bile duct by the current RFA system can induce serious complications. Recently, a new RFA system with automatic temperature control was developed. In the present study, we examined the safety of the new RFA system in patients undergoing endobiliary RFA for extrahepatic MBS. Methods This prospective, multicenter study enrolled patients with unresectable or inoperable extrahepatic (> 2 cm from the hilum) MBS. Endobiliary RFA was performed using a newly developed RFA catheter (ELRA™, STARmed, Goyang, Korea) at a setting of 7 or 10 W for 120 s and with a target temperature of 80°C. A self-expandable metallic stent was inserted after endobiliary RFA. The rate of procedure-related adverse events was assessed. Results The 30 patients were enrolled in this study. Cholangiocarcinoma was diagnosed in 19 patients, pancreatic cancer was found in 9, and gallbladder cancers were recorded in 2. The mean stricture length was 22.1 ± 6.6 mm. Post-procedural adverse events occurred in three patients (10.0%; 2 mild pancreatitis and 1 cholangitis) without hemobilia and bile duct perforation. The pancreatitis and cholangitis resolved with conservative treatment. The cumulative duration of stent patency and survival were 236 and 383 days, respectively. Conclusions Automatic temperature-controlled endobiliary RFA using a newly developed catheter was safely applied in patents with extrahepatic MBS. Further prospective studies are needed to confirm the efficacy of endobiliary RFA for MBS.

Recent advances in cholangiopancreatoscopy technology permit image-enhanced endoscopy (IEE) for pancreatobiliary diseases. There are limitations in endoscopy performance and in the study of the clinical role of IEE in bile duct or pancreatic duct diseases. However, currently available IEEs during cholangiopancreatoscopy including traditional dye-aided chromoendoscopy, autofluorescence imaging, narrow-band imaging, and i-Scan have been evaluated and reported previously. Although the clinical role of IEE in pancreatobiliary diseases should be verified in future studies, IEE is a useful promising tool in the evaluation of bile duct or pancreatic duct mucosal lesions.

Background and Aims EUS-guided fine-needle aspiration/biopsy (EUS-FNA/B) has a high diagnostic accuracy for pancreatic tumors. Most reports have focused on the diagnostic yield of cytology or histology; the ability of various FNA/B techniques to obtain an adequate mass of cells or tissue has rarely been investigated. Methods Patients with suspected pancreatic malignancy underwent EUS-FNB using a 22-gauge ProCore needle by either the stylet slow-pull-back technique (group A), conventional negative suction after stylet removal (group B), or non-suction after stylet removal (group C) in the absence of an on-site cytopathologist. The adequacy of the 3 techniques based on the diagnostic yield, cellularity, blood contamination, and core-tissue acquisition was evaluated. Results A total of 50 patients (27 males) were analyzed. The mean tumor size was 21 to 40 mm in 54%. The rate of a good or excellent proportion of cellularity was highest in group A compared with groups B and C (72% vs 60% vs 50%, P = .049). A >25% rate of blood contamination was more prevalent in group B (30% vs 42% vs 10%, P = .009). The rate of adequate core-tissue acquisition was not different (52% vs 34% vs 50%, P = .140). Based on the multivariate generalized estimation equation, the stylet slow-pull-back technique and a tumor size >40 mm were favorable factors for diagnostic adequacy. Conclusions The stylet slow-pull-back technique might enable acquisition of tissue and assessment of cellularity for the diagnosis of pancreatic tumors suspected to be malignant. (Clinical trial registration number: KCT0002190.)

ratio of cholangiocarcinoma (intrahepatic or extrahepatic), gall bladder cancer, and ampulla of Vater cancer was 41 (63.1%):18 (27.7%):6 (9.25%). Half of the patients (33 patients, 50.8%) were treated with gemcitabine-based and 28 patients (43.1%) with 5-fluo- rouracil-based therapy. The response rate was 3.0% and disease control rate was 21.5% in intention-to-treat analysis. Median overall survival (OS) was 7.2 months (95% confidence interval (CI), 3.9 to 10.5 months) and median progression free survival (PFS) was 3.7 months (95% CI, 2.5 to 4.9 months). In multivariate analysis, patients with good performance status (PS) (P = 0.001) and chemo-sensi- tive tumor to 2nd line chemotherapy (P = 0.000) had longer PFS as compared to the others. In addition, patients with good PS (P = 0.003), chemo-sensitive tumor to 1st line (P = 0.046), and 2nd line chemotherapy (P = 0.004) were good prognostic factors for OS. Conclusion: The effect of 2nd line chemotherapy in advanced BTC was modest and maybe beneficial in select patients.

Newly introduced direct peroral cholangioscopy and the development of video choledochoscopes have enabled more defined observation of bile duct mucosal lesions with clearer images. Narrow-band imaging (NBI) is a unique endoscopic imaging technology that provides enhanced endoscopic images of surface mucosal structures and its superficial microvessels. Advanced cholangioscopy and NBI are expected to be useful for precise evaluation and correct diagnosis of biliary tract diseases. However, the diagnostic value of advanced bile duct imaging with cholangioscopy requires further evaluation.

Background and Study Aims Endoscopic ultrasound (EUS)-guided fine needle aspiration (EUS-FNA) is one of the alternative methods for tissue sampling of liver solid mass. However, the diagnostic efficacy using cytology alone was limited. In this study, we evaluate the diagnostic accuracy of EUS-guided fine needle biopsy (EUS-FNB) as a percutaneous biopsy rescue for liver solid mass. Patients and Methods The EUS-FNB using core biopsy needle for liver solid mass was performed prospectively for patients who were failure to acquire a tissue or achieve a diagnosis using percutaneous liver biopsy. The primary outcome was the diagnostic accuracy of EUS-FNB for malignancy and specific tumor type. The secondary outcomes were the median numbers of passes required to establish a diagnosis, the proportions of patients in whom immunohistochemical (IHC) stain was possible and obtained adequate specimen, and safety of EUS-FNB. Results Twenty-one patients (12 women; mean age, 63 years [range, 37–81]) underwent EUS-FNB for solid liver masses. The median number of needle passes was 2.0 (range, 1–5). On-site cytology and cytology with Papanicolaou stain showed malignancy in 16 patients (76.2%) and 17 patients (81.0%), respectively. In histology with HE stain, 19 patients (90.5%) were diagnosed malignancy and optimal to IHC stain. The overall diagnostic accuracy for malignancy and specific tumor type were 90.5% and 85.7%, respectively. No complications were seen. Conclusions EUS-FNB with core biopsy needle for solid liver mass may be helpful in the management of patients who are unable to diagnose using percutaneous liver biopsy.

Direct peroral cholangioscopy (POC) using an ultra-slim upper endoscope is one modality of POC for intraductal endoscopic evaluation and treatment of the bile duct. Choledochoduodenostomy (CDS) is one modality of biliary bypass surgery that provides a new route to the bile duct. We carried out direct POC using an ultra-slim upper endoscope without the use of accessories in 10 patients (four sump syndromes, three bile duct strictures and three intrahepatic duct stones) previously undergoing surgical CDS. Direct POC was successful in all patients. The use of an intraductal balloon catheter was required in one patient for advancement of the endoscope into the bile duct. Distal bile ducts with sump syndromes were cleared using baskets and water irrigation under direct POC. Cholangiocarcinoma was diagnosed in one patient with hilar bile duct stricture after cholangioscopic evaluation and a targeting forceps biopsy under direct POC. Intrahepatic duct stones were successfully extracted after intraductal fragmentation under direct POC. Oozing bleeding occurred during intraductal lithotripsy but stopped spontaneously. Direct POC using an ultra-slim upper endoscope without the assistance of accessories can easily be carried out in patients undergoing CDS.