Detection and endoscopic classification of intraductal neoplasms of the bile duct by peroral cholangioscopy with narrow-band imaging (with videos).

BACKGROUND AND AIMS: Indirect diagnostic modalities are unsatisfactory for detecting intraductal neoplasm of the bile duct (IN-B), which can be detected by peroral cholangioscopy (POC) with narrow-band imaging (NBI). We investigated the POC findings of IN-B and developed a feasible endoscopic classification system. METHODS: Four hundred seventy-one patients who underwent direct POC from April 2008 to July 2020 were enrolled. Intraductal superficial lesions of the bile duct (ISL-Bs) were classified according to surface structure and microvascular pattern on POC with NBI and correlated to histologic findings after POC-guided forceps biopsy sampling (POC-FB) or surgery. The primary outcome was the detection rate of IN-Bs, and the secondary outcomes were the associations of POC findings with IN-B, technical success rates of POC and POC-FB, and adverse events. RESULTS: Direct POC was successful in 458 of 471 patients (97.2%). Among the patients, 131 (27.8%) exhibited ISL-Bs. The technical success rate of POC-FB was 94.7% (124/131). Among the 124 patients who underwent POC-FB, IN-B was revealed in 54 (43.5%), for a detection rate of 11.8% (54/458). Papillary lesions (P = .041), nodular lesions (P = .044), and irregularly or regularly dilated and tortuous vessels (P = .004 and P = .006, respectively) were POC findings associated with IN-B. The area under the receiver-operating characteristic curve of the novel classification system was .899. CONCLUSIONS: POC with NBI can be useful for the detection of IN-Bs. Our novel classification system based on both surface structure and microvascular pattern may allow differentiation of IN-B from ISL-Bs.

Feasibility of Cholangioscopy Using Multibending Ultra-Slim Endoscope Through a Lumen-Apposing Metal Stent for Choledochoduodenostomy.

BACKGROUND AND AIMS: Endoscopic ultrasound (EUS) guided choledochoduodenostomy using a lumen-apposing metal stent (LAMS) allows access to the biliary system with a sufficiently large diameter stent. However, an appropriate endoscope for this purpose is required. We evaluated the feasibility of per-oral cholangioscopy (POC) using a multibending ultra-slim endoscope through a LAMS for EUS-guided choledochoduodenostomy. METHODS: Twelve patients who underwent EUS-guided choledochoduodenostomy, followed by POC via a LAMS, were enrolled. POC was performed with an multibending ultra-slim endoscope. The primary outcome was technical success, defined as examination of both hepatic ducts and either the distal common bile duct or stricture site within 10 min. The types of intervention and adverse events were also assessed. RESULTS: Technical success was achieved in all cases with the multibending ultra-slim endoscope. Narrow-band imaging endoscopy was performed in five cases (41.7%) and POC-guided targeted biopsy was performed in three cases (25.0%). Stone extraction during POC was performed in two patients (16.7%) and foreign body removal from the intrahepatic duct was performed in one patient. One patient underwent additional metal stent insertion under direct visualization. After POC, no stent migration or severe adverse events were seen in any case. CONCLUSIONS: POC using a multibending ultra-slim endoscope for diagnostic or therapeutic purposes can be performed effectively and safely through a LAMS after EUS-guided choledochoduodenostomy.

Efficacy of narrow-band imaging during peroral cholangioscopy for predicting malignancy of indeterminate biliary strictures (with videos).

BACKGROUND AND AIMS: Direct peroral cholangioscopy (POC) can be useful when combined with narrow-band imaging (NBI) to explore the etiologies of indeterminate biliary strictures. We evaluated the efficacy of NBI compared with that of conventional white-light imaging (WLI) during POC diagnosis of indeterminate biliary strictures. METHODS: Consecutive patients with indeterminate biliary strictures were enrolled from 2016 to 2019. The primary outcome was diagnostic accuracy, and secondary outcomes were technical success, adverse events, and visualization quality when predicting malignancy. RESULTS: Seventy-one patients underwent direct POC under NBI during targeted biopsy sampling. The strictures were successfully explored and adequate biopsy samples obtained in 67 of 71 patients (94.4%). In terms of visual impression, WLI and NBI afforded 75.0% and 87.5% sensitivity, 82.9 and 91.4% specificity, and 82.8 and 91.3% accuracy, respectively. The areas under the WLI and NBI receiver-operating characteristic curves were .80 and .96 (P = .01). Under NBI, the visualization quality of surface structures, microvessels, and lesional margins was higher than that under conventional WLI (P < .05). CONCLUSIONS: Direct POC under NBI effectively and accurately predicts malignancies of indeterminate biliary strictures. NBI effectively illuminated surface structures, microvessels, and lesional margins.

Peroral cholecystoscopy using a multibending ultraslim endoscope through a lumen-apposing metal stent for endoscopic ultrasound-guided gallbladder drainage: a feasibility study.

BACKGROUND: Endoscopic ultrasound-guided gallbladder drainage (EUS-GBD) using a lumen-apposing metal stent (LAMS) has rendered endoscopic gallbladder assessment through a stent possible, but an appropriate endoscope is required. We assessed the feasibility of peroral cholecystoscopy (POCC) using a multibending ultraslim endoscope passed through a LAMS after EUS-GBD. METHODS: 14 patients with a LAMS for EUS-GBD who consecutively underwent POCC were included. POCC was performed using a multibending endoscope inserted through the LAMS. The primary outcome was the technical success rate, defined as complete endoscopic examination of the gallbladder from the orifice of the cystic duct to the fundus. The types of intervention and adverse events were recorded. RESULTS: 17 POCCs were performed in 14 patients. Of the 17 POCCs, 15 (88.2 %) were technically successful. Narrow-band imaging endoscopy was performed in 12 procedures (70.6 %), and cholecystoscopy-guided target biopsies were obtained in six. Gallstone extraction was performed in two patients. After POCC, all LAMSs remained stable and no adverse events were observed. CONCLUSIONS: POCC using a multibending ultraslim endoscope can be effectively and safely performed through a LAMS after EUS-GBD.

Modified non-flared fully covered self-expandable metal stent for preoperative biliary drainage in pancreatic cancer.

BACKGROUND AND AIM: Durable biliary drainage is essential in patients with pancreatic cancer in the era of effective neoadjuvant chemotherapy (NACT). Plastic stent (PS) tends to occlude easily, and current metal stents are designed for nonresectable cancer. We evaluated the efficacy of a modified non-flared fully covered self-expandable metal stent (M-FCSEMS) during the perioperative period in patients with resectable or borderline resectable pancreatic cancer. METHODS: Consecutive patients with resectable or borderline resectable pancreatic ductal adenocarcinoma had a 12-mm M-FCSEMS (M-FCSEMS group) or 7-Fr PS (PS group) placed for biliary decompression before NACT or curative-intent surgery. The primary outcome was the re-intervention rate, and secondary outcomes were technical success, stent patency, and adverse events (AEs). RESULTS: Endoscopic stent placement was technically successful in all 60 patients. Twenty-three patients underwent surgery and 37 NACT before surgery. Re-intervention was performed in 10.0% (3/30) of patients in the M-FCSEMS group and 36.7% (11/30) of patients in the PS group (P = 0.030). The stent patency at 180 days was 89.8% (95% confidence interval, 77.3-100.0%) in the M-FCSEMS group and 30.2% (95% confidence interval, 11.4-80.0%) in the PS group (P < 0.0001). Stent-related AEs occurred in 10.0% (3/30) in the M-FCSEMS group and 40.0% (12/30) in the PS group (P = 0.015). Surgery-related AEs occurred in 10.5% (2/19) and 14.3% (3/21) in the M-FCSEMS and PS groups (P = 0.549). CONCLUSIONS: Modified non-flared fully covered self-expandable metal stents are effective and safe for durable biliary drainage in patients with resectable or borderline resectable pancreatic cancer during the perioperative period.

Endoscopic Bilateral Stent-in-Stent Versus Stent-by-Stent Deployment in Advanced Malignant Hilar Obstruction: A Meta-Analysis and Systematic Review.

BACKGROUND AND AIM: There is no clear data to compare the effectiveness and safety of bilateral stent-in-stent (SIS) or stent-by-stent (SBS) deployment for advanced malignant hilar obstruction (MHO). This meta-analysis was done to investigate clinical outcomes of these deployment methods. METHODS: We did a literature search to identify studies that reported the clinical outcomes of bilateral metal stents in patients with advanced MHO. Weighed pooled rates (WPR) along with 95% confidence interval (95% CI) were calculated in order to compare outcomes including technical and clinical success, adverse events, and stent occlusion between the two groups. We conducted a meta-analysis using a random-effects model. RESULTS: Five comparative studies with 250 patients, and 20 single-arm studies for the SIS or SBS method were eligible for the meta-analysis and systematic review. The bilateral SIS deployment had a significantly higher technical success rate than did SBS deployment (OR 6.43; 95% CI 1.08-38.09). There was no difference in the clinical success (OR 1.23; 95% CI 0.45-3.38), overall adverse events rates (OR 0.42; 95% CI 0.15-1.18), or overall occlusion rate (OR 1.55; 95% CI 0.89-2.70). As a single-armed group, WPR of technical success of the SIS and SBS groups was 96.4% and 89.6%, respectively. Clinical success was 97.5% and 98.3%. Overall, adverse events were 35.9% and 22.6%. Occlusion rates were 27.7% and 37.7%. CONCLUSIONS: Although there was a lack of quality data and heterogeneity, bilateral SIS deployment had a higher technical feasibility than did the SBS method in patients with advanced MHO, without differences in terms of clinical success, adverse events, or occlusion rates.

A Preliminary Study on the Efficacy of Single-Operator Cholangioscopy with a New Basket for Residual Stone Retrieval After Mechanical Lithotripsy.

BACKGROUND AND AIM: The detection of residual or fragmented common bile duct (CBD) stones after lithotripsy can be improved by the high-resolution imaging quality of digital, single-operator cholangioscopy (SOC). However, therapeutic interventions for the removal of residual CBD stones are limited by the lack of appropriate tools. We retrospectively evaluated the role of SOC and the newly developed Dormia basket for the evaluation and removal of stones remaining after lithotripsy. METHODS: Thirty-four patients who had undergone lithotripsy for retained CBD stones with no evidence of filling defects in occluded balloon cholangiography from March 2017 to October 2018 were included in the study. After balloon cholangiography, the bile duct was evaluated by SOC for complete evacuation of the stones. The detected residual CBD stones were directly retrieved by inserting the newly developed Dormia basket into the working channel of the SOC. The incidence of residual stones detected by SOC and the success rate of residual stone retrieval by SOC were investigated. RESULTS: Digital SOC was successfully performed in all patients. Of these, 11 patients (32.4%) had residual CBD stones. The residual stones were successfully removed in 10 patients (90.9%) by SOC using the Dormia basket, except in one case of residual stones left in the hepatic duct. There were no adverse events associated with the SOC procedures or direct stone removal. CONCLUSIONS: Digital SOC combined with the newly developed Dormia basket was useful for the detection and extraction of residual CBD stones under direct visualization after lithotripsy.

Use of peroral cholangioscopy to screen for neoplastic bile duct lesions in patients with bile duct stones (with videos).

BACKGROUND AND AIMS: Although cholangiocarcinomas (CCAs) can be diagnosed using several modalities, the detection of early-stage cancers remains unsatisfactory. We explored whether peroral cholangioscopy (POC) could be used to screen for neoplastic bile duct lesions including CCAs in patients with bile duct stones. METHODS: Two hundred seven patients who underwent endoscopic removal of bile duct stones were enrolled between August 2010 and July 2018. The primary outcome was the detection rate of intraductal neoplastic biliary lesions by direct POC. Secondary outcomes were the technical success rates of direct POC and POC-guided forceps biopsy sampling (POC-FB), the diagnostic accuracy of the direct POC findings, adverse events, and the number needed to screen to detect a neoplastic bile duct lesion. RESULTS: Direct POC was successful in 199 of 207 patients (96.1%). Mild cholangitis developed in 2 patients (1.0%) and was treated conservatively. Of the 199 successfully performed POCs, 31 patients (15.6%) exhibited abnormal intraductal mucosal lesions. The technical success rate of POC-FB was 90.3% (28/31 patients). The pathologic diagnoses after POC-FB were CCAs (n = 4), intraductal papillary neoplasms of the bile duct (IPN-B) (n = 2), an adenoma with dysplasia (n = 1), and benign lesions (n = 21). Direct POC correctly distinguished non-neoplastic from neoplastic bile duct lesions in 91.6% of patients. Curative surgical resection was performed for the 5 patients with CCAs or IPN-B. The number needed to screen to detect a neoplastic bile duct lesion was 29.6. CONCLUSIONS: Direct POC using a dedicated, ultraslim upper endoscope usefully screens for neoplastic bile duct lesions including CCAs in selected patients with bile duct stones.

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.

Efficacy of a modified short fully covered self-expandable metal stent for perihilar benign biliary strictures.

BACKGROUND AND AIM: Endoscopic management of a benign biliary stricture (BBS) on the hilum is complicated and challenging. Although the placement of a fully covered self-expandable metal stent (FCSEMS) is possible to increase effectiveness, stent migration and stent-induced adverse events are problematic. We aimed to evaluate the usefulness of a modified short FCSEMS with a long lasso in patients with a difficult perihilar BBS. METHODS: Patients with perihilar BBS within 2 cm from the hilar confluence that failed initially with plastic stents were enrolled. A modified short FCSEMS was deployed and then removed 5-6 months later. The primary outcome was clinical success. Other technical success, adverse events, endoscopic success of stent removal, and recurrence of stricture during the follow-up period were measured. RESULTS: Endoscopic intraductal placement was technically successful in all patients (n = 19). Combined contralateral plastic stent placement was performed in 13 patients (68.4%). The median duration of stent placement was 163 days (range, 138-196 days). Endoscopic stent removal was successful in all patients except one spontaneous distal migration. Stricture resolution without de novo focal stricture occurrence was 100%. Endoscopic stone removal after stricture improvement was successful in all 13 patients with bile duct stones above the stricture. During a follow-up period (median 635 days) after stent removal, only one recurrence developed. CONCLUSIONS: Temporary placement of a modified intraductal short FCSEMS with or without a contralateral plastic stent improved perihilar BBS in patients that primarily failed by plastic stents. Combined biliary stones were also successfully removed after stricture resolution.

Preliminary study of a modified, nonflared, short, fully covered metal stent for refractory benign pancreatic duct strictures (with videos).

BACKGROUND AND AIMS: Fully covered self-expanding metal stents (FCSEMSs) are considered to be more effective than plastic stents for the treatment of main pancreatic duct (MPD) strictures associated with chronic pancreatitis (CP) because of their larger diameter and exertion of a radial expansion force. However, the current FCSEMSs have several limitations. To overcome these, a novel modified nonflared FCSEMS was developed. In this study we conducted a prospective long-term follow-up evaluation of the efficacy of the novel FCSEMS for the treatment of refractory benign PD strictures in patients with CP. METHODS: Consecutive patients with symptomatic CP associated with refractory MPD strictures were enrolled prospectively in this single-arm study. The nonflared FCSEMS was placed intraductally or transpapillary according to the location and length of the stricture. Stent removal was performed at 3 months after placement. The primary outcome was the resolution of the pancreatic ductal stricture. RESULTS: Endoscopic placement of modified nonflared FCSEMSs was technically successful in all 25 patients. Intraductal FCSEMS placement was performed in 14 patients (56.0%). Stents of diameter 8 mm were used in 17 patients (68.0%). Stents of lengths 3 and 5 cm were inserted in 22 (88.0%) and 3 (12.0%) patients, respectively. In 1 patient (4.0%), stent migration developed. All other stents were removed successfully. After stent removal, resolution of the MPD stricture was confirmed in all patients, and no FCSEMS-related de novo stricture was observed. During the follow-up period (median, 34 months; interquartile range, 25-56) after the stents had been removed from the 25 patients, reintervention for recurrence of MPD stricture with abdominal pain was performed in 2 patients (8.0%). CONCLUSIONS: Endoscopic placement of a novel modified nonflared FCSEMS resulted in long-term stricture resolution with pain relief and reduced the rate of stent-related adverse events, particularly stent migration and stent-induced de novo MPD stricture. (Clinical trial registration number: UMIN000035681.).

Efficacy of 3 fine-needle biopsy techniques for suspected pancreatic malignancies in the absence of an on-site cytopathologist.

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.).

Tissue acquisition for diagnosis of biliary strictures using peroral cholangioscopy or endoscopic ultrasound-guided fine-needle aspiration.

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.

Usefulness of newly modified fully covered metallic stent of 12 mm in diameter and anti-migration feature for periampullary malignant biliary strictures: Comparison with conventional standard metal stent.

BACKGROUNDS: Fully covered self-expandable metal stent (FCSEMS) are preferred for distal malignant biliary stricture (MBS). However, stent migration is a major adverse event of FCSEMS, especially for far distal MBS. We evaluated the usefulness of newly modified FCSEMS (M-FCSEMS) having 12 mm in diameter and anti-migration feature to minimize stent migration compared with the conventional FCSEMS (C-FCSEMS). METHODS: Total 102 patients were enrolled between January 2015 and September 2017 in this prospective comparative study; 50 were allocated to the M-FCSEMS group and 52 to the C-FCSEMS group. The primary outcome was stent migration, and the secondary outcomes were other adverse events, stent occlusion rate, and stent patency during the follow-up period. RESULTS: The baseline characteristics of the two groups did not significantly differ. Endoscopic stent placement was technically successful in all patients. Stent migration occurred in 8.0% (4/50) of the patients in the M-FCSEMS group and 23.1% (12/52) of those in the C-FCSEMS group (P = 0.036). The other adverse events, including stent-related pancreatitis and cholecystitis did not significantly differ between the two groups (P = 0.415). Stent occlusion occurred in 23.9% (11/46) of the patients in the M-FCSEMS group and 37.5% (15/40) in the C-FCSEMS group (P = 0.171). Stent patency was significantly longer in the M-FCSEMS group than in the C-FCSEMS group (228 vs 157 days, P = 0.048). CONCLUSIONS: Modified FCSEMS with 12-mm diameter and anti-migration feature significantly decreased the risk of stent migration and had longer patency compared with C-FCSEMS in patients with periampullary MBS.

Modified non-flared fully covered self-expandable metal stent versus plastic stent for preoperative biliary drainage in patients with resectable malignant biliary obstruction.

BACKGROUND AND AIM: Fully covered self-expandable metal stents (FCSEMS) may be better than plastic stents (PS) for preoperative biliary drainage (PBD) to relieve cholangitis or jaundice for resectable malignant biliary obstruction (MBO). However, modification of current FCSEMS designed originally for nonresectable MBO is needed to be a proper stent for PBD. The aim of this study was to evaluate the possible superiority of non-flared modified FCSEMS (M-FCSEMS) with 12-mm diameter and waist of central portion over PS in patients with resectable MBO. METHODS: Eighty-five consecutive patients underwent PBD followed by operation from August 2015 to December 2017. In each M-FCSEMS and PS group, 29 patients were matched for age, sex, body mass index, and preoperative albumin and bilirubin levels. RESULTS: The overall technical success rates of PBD using M-FCSEMS and PS were 100%. The time to operation was similar between groups (18.6 ± 10.8 vs 19.3 ± 11.6 days, respectively; P = 0.843). The prevalence of PBD-related adverse events (AEs) was 6.9% (2/29) in the M-FCSEMS group versus 27.6% (8/29) in the PS group (P = 0.037). Re-intervention before operation was required in 20.7% (6/29) of patients in the PS group but no patients in the M-FCSEMS group (P = 0.023). No differences were found between perioperative AEs in the M-FCSEMS and PS groups (27.5% vs 31.0%, respectively; P = 0.773). CONCLUSION: Modified FCSEMS led to lower PBD-related AEs, re-intervention rate, and comparable perioperative AEs compared with PS. M-FCSEMS may be a potential novel stent for PBD in patients with resectable MBO.

Direct peroral cholangioscopy for diagnosis of bile duct lesions using an I-SCAN ultraslim endoscope: a pilot study.

Background and study aims I-SCAN is a computed virtual chromoendoscopy (CVC) system designed to enhance surface and vascular patterns. In this study, we evaluated the usefulness of direct peroral cholangioscopy (POC) using I-SCAN compared with a conventional white-light image (WLI) to diagnose bile duct lesions. Patients and methods Patients with mucosal lesions in the bile duct detected during direct POC were enrolled prospectively. The quality of endoscopic visualization and the visual diagnosis were assessed using I-SCAN and WLI modes, respectively, during direct POC. Results A total of 20 patients (9 malignant and 11 benign lesions) underwent I-SCAN to evaluate lesions in the bile duct using direct POC. The quality of endoscopic visualization using direct POC with I-SCAN was significantly higher than that of WLI for surface structure (P = 0.04), surface microvascular architecture (P = 0.01), and margins (P = 0.02). Overall diagnostic accuracy of the visual diagnosis was not different between I-SCAN and WLI (90.0 % vs. 75.0 %; P = 0.20). Conclusion Direct POC using CVC by I-SCAN seems to be helpful for evaluating mucosal lesions of the bile duct, without the interference from bile. CLINICAL TRIAL REGISTRATION: UMIN000021009.

KRAS mutation analysis by next-generation sequencing in endoscopic ultrasound-guided sampling for solid liver masses.

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.

Wire-guided intraduodenal ultrasonography using a catheter probe in the differential diagnosis of enlarged ampullary lesions.

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.

Efficacy of midazolam- versus propofol-based sedations by non-anesthesiologists during therapeutic endoscopic retrograde cholangiopancreatography in patients aged over 80 years.

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.

A newly modified access balloon catheter for direct peroral cholangioscopy by using an ultraslim upper endoscope (with videos).

BACKGROUND AND AIMS: Direct peroral cholangioscopy (POC) by using an ultraslim upper endoscope has been increasingly applied for diagnosis and treatment of diverse biliary diseases. Recently, an intraductal balloon catheter has been used commonly to guide the flexible ultraslim endoscope. However, accessibility into the bile duct remains a limitation of the procedure. The aim of this study was to evaluate the feasibility and success rate of an intraductal balloon-guided direct POC by using an ultraslim endoscope with a newly modified 5F balloon catheter. METHODS: In total, 36 patients with biliary obstruction were included prospectively for a direct POC by using an ultraslim endoscope with a newly modified intraductal 5F balloon catheter. The main outcome measure was technical success, defined as successful advancement of the ultraslim endoscope into the obstructed segment of the biliary tree or the bifurcation. Secondary outcomes were mean time for the total procedure, intubation into the common bile duct and advancement up to the target site after intubation of the ultraslim endoscope, technical success rates of diagnostic and therapeutic interventions, and adverse events. RESULTS: The intraductal balloon-guided direct POC using a newly modified 5F balloon catheter was completed successfully in 35 of 36 patients (97.2%). The mean times for total procedure, intubation into the distal common bile duct, and advancement up to the obstructed bile duct segment were 27.3 ± 7.2, 2.2 ± 0.5, and 0.8 ± 0.4 minutes, respectively. In total, 49 interventions were performed in 35 patients, excluding 1 patient in whom we failed to perform direct POC. Technical success of the interventions was achieved with 44 of 49 procedures (89.8%). No adverse events, including cholangitis, were observed. CONCLUSIONS: A newly modified 5F balloon catheter seemed to facilitate performing intraductal balloon-guided direct POC for direct visual examination of the bile duct in patients with biliary obstruction. Continued development of endoscopes and accessories are expected to further improve the performance of direct POC.