Clinical evaluation of a novel drill dilator as the first-line tract dilation technique during EUS-guided biliary drainage by nonexpert hands (with videos).

BACKGROUND AND AIMS: In cases in which tract dilation fails using the initially selected dilation device during EUS-guided hepaticogastrostomy (EUS-HGS), dilation should be re-attempted using another device. However, switching from one device to another during the procedure is often associated with prolonged procedure time and deviation from the correct axis. Therefore, it is highly desired that the initial tract dilation succeeds on the first attempt. Recently, a novel drill dilator has become available in Japan. Because there have been no previous studies comparing this novel device versus others as an initial dilation device, this article reports on the technical feasibility of this novel device for use during EUS-HGS and compares it with a balloon catheter. METHODS: This retrospective study included patients who underwent EUS-HGS using a self-expandable metal stent between October 2021 and October 2022. Excluded from the study were patients who underwent EUS-HGS using a plastic stent or stent deployment without tract dilation. The primary outcome in this study was the technical success rate of initial tract dilation using the drill dilator. This dilator has been available at our hospital since June 2022. Thus, EUS-HGS was performed using this device as the primary dilation device from June 2022 to October 2022. As the control group, we corrected patients who underwent EUS-HGS using a 4-mm balloon catheter as the primary dilation device from October 2021 to May 2022. RESULTS: A total of 49 patients were included: 19 underwent EUS-HGS using the drill dilator and 30 underwent EUS-HGS using a balloon catheter. EUS-HGS using the drill dilator initially was performed mainly by nonexpert hands (n = 19), whereas only some procedures in the balloon catheter group were performed by nonexpert hands (n = 2). Although the initial tract dilation was successful in all patients in the drill dilator group (19 of 19 [100%]) and in 29 (97%) of 30 in the balloon catheter group, additional tract dilation was needed in 73.7% (14 of 19) of the drill dilator group upon insertion of the 8.5F stent delivery system. In contrast, the stent delivery system insertion was successful without additional tract dilation in all patients in the balloon catheter group. CONCLUSIONS: The novel drill dilator might be useful as a dilation device; however, the balloon dilation technique should be selected first upon deploying a dedicated metal stent with an 8.5F stent delivery system.

Prospective comparison study between 19-gauge needle with .025-inch guidewire and 22-gauge needle with novel .018-inch guidewire during EUS-guided transhepatic biliary drainage (with video).

BACKGROUND AND AIMS: If the diameter of the intrahepatic bile duct is much less dilated, bile duct puncture with a 19-gauge needle can be challenging during EUS-guided biliary drainage (EUS-BD). These characteristics can decrease the difficulty of bile duct puncture, but use of a 22-gauge needle is less feasible because of poor visibility, maneuverability, and stiffness of the conventional .018-inch guidewire. A novel, improved .018-inch guidewire has recently become available. We conducted a prospective study to evaluate the technical feasibility and safety of EUS-BD in patients with insufficient bile duct dilatation using a 22-gauge needle and the new .018-inch guidewire. METHODS: A 22-gauge needle was used as the puncture needle for intrahepatic bile ducts of diameters <1.5 mm, and a 19-gauge needle was selected for diameters ≥1.5 mm. As the primary endpoint of the study, the technical success rate of EUS-BD using a 22-gauge needle with the novel .018-inch guidewire was evaluated in patients with insufficient dilation of the intrahepatic bile duct. RESULTS: Forty-one patients who required EUS-BD were enrolled (22-gauge needle group, n = 18; 19-gauge needle group, n = 23). Technical success was obtained in all patients in the 19-gauge needle group. In the 22-gauge needle group, technical failure occurred in 2 patients because of nonidentification of the intrahepatic bile duct on EUS (technical success rate, 88.9%), and puncture of the bile duct itself was not performed in these patients. Mean procedure time was similar between the groups. Adverse events were observed in 16.7% of patients (3/16) in the 22-gauge needle group and in 34.8% of patients (8/23) in the 19-gauge needle group. CONCLUSIONS: Outcomes of using a 22-gauge needle with a novel .018-inch guidewire were comparable with a 19-gauge needle with a .025-inch guidewire, even in the case of insufficient intrahepatic bile duct dilatation. These results require verification in a prospective, randomized trial comparing 22-gauge and 19-gauge needles with a larger sample size. (Clinical trial registration number: UMIN000044441.).

Current status of artificial intelligence analysis for endoscopic ultrasonography.

Endoscopic ultrasonography (EUS) is an essential diagnostic tool for various types of pancreatic diseases such as pancreatic tumors and chronic pancreatitis; however, EUS imaging has low specificity for the diagnosis of pancreatic diseases. Artificial intelligence (AI) is a mathematical prediction technique that automates learning and recognizes patterns in data. This review describes the details and principles of AI and deep learning algorithms. The term AI does not have any definite definition; almost all AI systems fall under narrow AI, which can handle single or limited tasks. Deep learning is based on neural networks, which is a machine learning technique that is widely used in the medical field. Deep learning involves three phases: data collection and annotation, building the deep learning architecture, and training and ability validation. For medical image diagnosis, image classification, object detection, and semantic segmentation are performed. In EUS, AI is used for detecting anatomical features, differential pancreatic tumors, and cysts. For this, conventional machine learning architectures are used, and deep learning architecture has been used in only two reports. Although the diagnostic abilities in these reports were about 85-95%, these were exploratory research and very few reports have included substantial evidence. AI is increasingly being used for medical image diagnosis due to its high performance and will soon become an essential technique for medical diagnosis.

Endoscopic ultrasonography-guided hepaticogastrostomy using a novel laser-cut type partially covered self-expandable metal stent (with video).

Endoscopic ultrasonography (EUS)-guided hepaticogastrostomy (HGS) is of clinical benefit in patients with failed endoscopic retrograde cholangiopancreatography (ERCP). However, some endoscopists are concerned about the potential risk of adverse events. Bile peritonitis due to bile leakage through the fistula is one of the possible adverse events following EUS-HGS. Recently, a novel laser-cut type partially covered self-expandable metal stent (PCSEMS), which is a dedicated stent for EUS-HGS, has become available. This stent has an uncovered part, despite it being a laser-cut type stent, along with a flared end. In addition, it uses a 7-Fr stent delivery. Therefore, tract dilation might not be needed to deploy the stent, which might reduce the incidence of stent migration. In this study, the safety of EUS-HGS using this novel laser-cut type PCSEMS was evaluated by assessing technical success, which was defined as successful stent deployment, and clinical success, which was defined as reduction in serum total bilirubin levels by 50% and resolution of symptoms related to biliary tract obstruction within 2 weeks. Five patients with unresectable malignant biliary obstruction underwent EUS-HGS using the novel stent. Stent deployment was successfully performed without tract dilation in four patients, although tract dilation using a balloon catheter was needed in one patient. Clinical success was obtained in all patients, and adverse events including abdominal pain and bile peritonitis were not observed in any of the patients. EUS-HGS without tract dilation can be safely performed using a novel laser-cut type PCSEMS. A prospective comparative study evaluating this stent versus conventional stents is needed to corroborate our results.

Electrohydraulic Lithotripsy for Pancreatic Duct Stones Under Digital Single-Operator Pancreatoscopy (with Video).

BACKGROUND: Recently, a digital single-operator cholangiopancreatoscope (DSOC) has become available. This system allows the performance of electrohydraulic lithotripsy (EHL) even within the main pancreatic duct (MPD). However, there are only few reports of EHL for MPD stones using SPY-DS. AIMS: The aim of this study was to evaluate the technical feasibility and efficacy of EHL for MPD stones under DSOC guidance. METHODS: Between October 2016 and August 2017, patients with MPD stones were retrospectively enrolled in this study. The presence of MPD stones was diagnosed by endoscopic ultrasound and MRCP. The patients' baseline characteristics and those of the stones, including their size, number, and site in the MPD, number of EHL procedures, and adverse events, were reviewed. RESULTS: A total of 21 patients were retrospectively enrolled. The etiologies of chronic pancreatitis were idiopathic (n = 4) and alcohol induced (n = 17). The pancreatic stone was variously located in the head (n = 6), body (n = 11), tail (n = 1), head and body (n = 2), and body and tail (n = 1) of the pancreas. Median pancreatic stone size was 12 mm, and the mean number of ERCP sessions was 1.29 (range 1-3). EHL was successfully performed in 15 patients (85.7%, 18/21), and the rate of complete stone clearance was 88.2% (18/21). Severe adverse events were not seen in any of the patients, although one patient developed mild acute pancreatitis. CONCLUSIONS: In conclusion, although additional case reports and prospective studies are needed, EHL under DSOC may be an option to treat MPD stones.

Recanalization for Tight Bile Duct-Jejunum Anastomosis Stricture Using Peroral Transliminal Cholangioscopy (with Video).

Recently, due to improvement of imaging modality, malignant tumor such as pancreatic or bile duct cancer can be detected at earlier stage. Therefore, the frequency of surgical treatment may be increasing. According to this background, benign biliary stricture in anastomosis site may also be increasing. This complication can lead to repeated cholangitis, obstructive jaundice, or liver abscess. Traditionally, interventional radiology such as percutaneous transhepatic biliary drainage (PTCD) or surgical re-anastomosis may be the first choice of treatment for benign biliary stricture in anastomosis site. Recently, double balloon enteroscopy-assisted endoscopic retrograde cholangiopancreatography (DB-ERCP) has emerged. This relatively novel procedure has less invasiveness compared with PTCD or surgical re-anastomosis. However, DB-ERCP has also several disadvantages such as long procedure time or low technical success rate if DB-ERCP is performed by non-expert hands. On the other hand, endoscopic ultrasound-guided biliary drainage has been developed as alternative biliary drainage technique. More recently, novel transluminal approach for biliary tract through endoscopic ultrasound-guided transluminal drainage route has been reported using digital single-operator cholangioscope. We herein report technical tips for peroral transluminal cholangioscopy using digital single-operator cholangioscope, and successfully performed recanalization for tight stricture of bile duct-jejunum anastomosis.

Prospective histological evaluation of a 20G core trap with a forward-cutting bevel needle for EUS-FNA of pancreatic lesions.

BACKGROUND: Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has been established as a method to obtain tissues of various organs. To obtain sufficient tissue has clinical impact to facilitate the diagnosis by clinical pathologists, the assessment and subtyping of various neoplasms, and for further immunohistochemical investigations of tumor type. Recently, a novel 20G core trap with a forward-cutting beveled FNA needle (ProC-F) has become available. The aim of this prospective study was to evaluate the feasibility and diagnostic yield of EUS-FNA for pancreatic lesions using this needle. PATIENTS AND METHOD: In this study, the first puncture was performed using the ProC-F. Only tissue obtained with the first puncture using the ProC-F was used to evaluate diagnostic yield of ProC-F. The second puncture was performed using a 22G standard FNA needle using the same technique as for the first puncture. Second puncture was performed if the endosonographer did not feel that sufficient tissue had not been obtained by first puncture. RESULTS: Fifty-three consecutive patients who underwent EUS-FNA for pancreatic lesions were prospectively enrolled. The technical success rate of EUS-FNA using the ProC-F was 98.1% (52/53). The rate of adequate tissue obtained by ProC-F was 96.2% (50/52). On the other hand, the rate of adequate tissue obtained by the standard needle was 71.1%. The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and accuracy of the ProC-F and the standard needle were 92.5, 100, 100, 76.9, and 94.0%, and 85.2, 100, 100, 55.6, and 87.5%, respectively. Diagnostic yield of ProC-F about sensitivity (P = 0.027), NPV (P = 0.035), and accuracy (P = 0.004) was significantly higher than of standard needle. Adverse events were not seen in any patients. CONCLUSIONS: Although only tissue obtained by the first puncture was evaluated, the rate of adequate tissue and the histologic diagnostic yield for pancreatic lesions were extremely high using the ProC-F.

Anti-Ro52 antibody level is an important marker of fetal congenital heart block risk in anti-Ro/SSA antibody positive pregnancy.

OBJECTIVE: The aims of this study are to determine the incidence of congenital heart block (CHB) in the Japanese population and identify maternal factors predicting fetal CHB in anti-Ro/SSA antibody positive pregnancy. METHODS: A retrospective study was performed using 52,147 clinical records of pregnancies followed in a single center. For 183 anti-Ro/SSA antibody-positive women, anti-Ro52 and Ro60 antibodies were measured, and the odds of CHB in relation to maternal clinical features were calculated by multivariate analysis. The receiver-operating characteristic (ROC) curves for predicting CHB were constructed for the titers of anti-Ro/SSA, anti-Ro52 and anti-Ro60 antibodies. RESULTS: Fetal CHB occurred in two pregnancies among those without known risks such as positive anti-Ro/SSA antibody or previous CHB-affected pregnancy, suggesting an incidence similar to that in Caucasian populations. As for the anti-Ro/SSA antibody positive pregnancies, the titers of anti-Ro/SSA, anti-Ro52 and anti-Ro60 antibodies were independent risk factors for fetal CHB and the use of corticosteroids before 18 gestational weeks was an independent protective factor. The area under the ROC was 0.84, 0.73 and 0.74 for anti-Ro52, anti-Ro60 and anti-Ro/SSA antibodies, respectively. CONCLUSION: CHB occurred in two among approximately 50,000 pregnancies without known risks such as positive anti-Ro/SSA antibody or previous delivery of CHB-affected babies. Measurement of anti-Ro52 antibody levels may be helpful in extracting a risk group of delivering CHB infants in the anti-Ro/SSA antibody positive pregnancy.

Prospective clinical study of endoscopic ultrasound-guided biliary drainage using novel balloon catheter (with video).

BACKGROUND AND AIM: On endoscopic ultrasound (EUS)-guided biliary drainage, fistula dilation may be accompanied by leakage of bile juice, potentially along with bacteria or air, so this procedure should be kept as simple and short as possible. To date, various techniques to dilate the fistula have been reported. This prospective, single-center, single-arm study evaluated the technical feasibility and safety of EUS-guided biliary drainage using novel balloon catheters. METHODS: Tip of novel balloon catheters is only 3 Fr and tapered, and the catheters also show favorable push ability. First, biliary tract was punctured using 19-G fine needle aspiration needle. Next, we immediately inserted the novel balloon catheter, and the biliary tract and intestinal wall were dilated. Then, we performed metallic stent placement without any dilation fistula. RESULTS: A total of 20 patients were prospectively enrolled in this study. Technical success rate was 100%. Eleven patients underwent EUS-guided choledochoduodenostomy, and nine patients underwent EUS-guided hepaticogastrostomy. Median procedure time was only 11 min (range, 8-16 min) for EUS-guided choledochoduodenostomy and 14 min (range, 11-18 min) for EUS-guided hepaticogastrostomy. Adverse events were seen in 15% (3/20; self-limited abdominal pain n = 2, peritonitis n = 1). CONCLUSIONS: Although additional cases and a randomized controlled comparison with another dilation technique such as the graded dilation or cystotome dilation technique are needed, our technique may be helpful for EUS-guided biliary drainage.

Clinical utility of endoscopic ultrasound-guided biliary drainage as a rescue of re-intervention procedure for high-grade hilar stricture.

BACKGROUND AND AIM: Re-intervention after stent placement for malignant hepatic hilum obstruction (HBO) is challenging. endoscopic ultrasound-guided biliary drainage (EUS-BD) has been developed as an alternative method for failed endoscopic retrograde cholangiopancreatography (ERCP). In this retrospective study, the clinical utility of EUS-BD as a rescue drainage technique for HBO patients who failed re-intervention under ERCP guidance was evaluated. METHODS: Between April 2012 and August 2015, patients with HBO were enrolled. Patients' characteristics, kinds of metallic stents, configuration of stent placement, overall survival, stent patency, and results of re-intervention were reviewed, along with the re-intervention technical success rate. RESULTS: The biliary stricture type was Bismuth type IV in 59% (23/39) and types IIIa and b in 20.5% (8/39) each. Biliary metallic stent placement was bilateral in 38.5% (15/39), and unilateral in 61.5% (24/39). Primary stent dysfunction was observed in 71.8% (28/39) of cases. Planned re-intervention under ERCP guidance was attempted in 26 patients. The technical success rate was 62% (16/26). For the 10 patients who failed re-intervention under ERCP guidance, EUS-BD was planned. The technical success rate was 100% (10/10). The procedure time was 25.8 min. Adverse events were not seen in any patients. Stent patency after re-intervention was not significantly different between ERCP (165 days) guidance and EUS-BD (152 days) guidance (P = 0.463) CONCLUSIONS: In conclusion, EUS-BD as a re-intervention method for metallic stent obstruction was safe and feasible. If ERCP was failed, EUS-BD may be one of option as re-intervention method for high-grade hilar stricture.

Evaluation of the safety of endoscopic radiofrequency ablation for malignant biliary stricture using a digital peroral cholangioscope (with videos).

BACKGROUND AND AIM: The clinical impact of catheter-based radiofrequency ablation (RFA) under endoscopic retrograde cholangiopancreatography (ERCP) guidance has recently been reported; however, severe adverse events have also been noted. If tumor is not present in the biliary tract, severe adverse events such as perforation or bleeding as a result of vessel injury around the biliary tract may occur. In addition, the effectiveness of RFA may not be sufficient based solely on radiographic guidance. The aim of the present study was to evaluate the actual feasibility of intraductal RFA by peroral cholangioscope (POCS) evaluation before/after RFA. METHODS: In this retrospective study carried out between July and September 2016, consecutive patients who underwent RFA for malignant biliary stricture and POCS evaluation before/after RFA were enrolled. Primary endpoint of this study was technical feasibility of RFA, which was evaluated by POCS. Secondary endpoints were rates and types of adverse event. RESULTS: A total of 12 consecutive patients were retrospectively enrolled in this study. Stent placement using uncovered metal stents had been previously done in six patients before RFA. Tumor was seen in the biliary tract in all patients. RFA was technically successful in all patients, and clinical success was confirmed in all patients by POCS imaging. Adverse events were seen in only one patient. Median stent patency was 154 days. CONCLUSIONS: RFA for malignant biliary stricture may be safe. To confirm the feasibility and efficacy of RFA, additional cases, prospective studies, and a comparison study between with and without endobiliary RFA are needed.

Prospective evaluation of digital single-operator cholangioscope for diagnostic and therapeutic procedures (with videos).

BACKGROUND AND AIM: Recently, the digital single-operator cholangioscope (SPY-DS) has become available. This system may allow diagnosis by direct visualization and allow performance of various therapeutic procedures. The aim of the present study was to prospectively evaluate the clinical utility of DSOCS for diagnostic and therapeutic procedures for biliary disease. METHODS: Technical success was defined as successful visualization of target lesions in the biliary tract and carrying out forceps biopsy as a diagnostic procedure, and successfully carrying out treatment such as guidewire insertion for the area of interest, electrohydraulic lithotripsy (EHL), or migrated stent removal. Also, the present study aimed at investigating diagnostic yield of the cholangioscopic findings and biopsy specimens. RESULTS: A total of 55 consecutive patients were prospectively enrolled in this study; a diagnostic procedure was done in 33 patients, and a therapeutic procedure was done in 22 patients. Overall accuracy of visual findings was 93%, with a sensitivity of 83%, a specificity of 89%, positive predictive value (PPV) of 83%, and negative predictive value (NPV) of 100%. However, the overall accuracy of forceps biopsy was 89%, with a sensitivity, specificity, and PPV of 100%, and NPV of 90%. Overall technical success rate of therapeutic procedures such as selective guidewire insertion, EHL or migrated stent removal was 91% (20/22). Finally, adverse events were seen in two cases in the diagnostic group, but were not seen in the therapeutic group. CONCLUSION: Although additional cases and a randomized, controlled study with another cholangioscope are needed, diagnostic and therapeutic procedures using SPY-DS appear to be feasible and safe.

Clinical Outcome of Endoscopic Ultrasound-Guided Liver Abscess Drainage Using Self-Expandable Covered Metallic Stent (with Video).

BACKGROUND: Percutaneous drainage (PCD) is now the first-line drainage method for liver abscess because of its minimal invasiveness and high technical success rate. However, this procedure has several disadvantages, such as extra-drainage and self-tube removal. Recently, EUS-guided liver abscess drainage (EUS-AD) has been developed. However, only a few reports of EUS-AD have been reported. In addition, the clinical benefits of PCD and EUS-AD have not been reported. AIMS: In the present study, the safety and feasibility of EUS-AD using fully covered SEMS (FCSEMS) and the clinical outcomes of EUS-AD and PCD were examined retrospectively. METHODS: Twenty-seven consecutive patients who underwent PCD or EUS-AD between April 2012 and April 2015 were included in this study. EUS-AD was performed using FCSEMS. In addition, to prevent stent migration, 7-Fr pig tail plastic stent was placed within FCSEMS. RESULTS: Technical success was achieved in all patients of both groups. Clinical success was 100 % in the EUS-AD group although it was 89 % in PCD group (P = 034). Three adverse events were seen in the PCD group (self-tube removal n = 1, tube migration n = 2), but no adverse events were seen in the EUS-AD group. The median hospital stay was significantly shorter in the EUS-AD group than in the PCD group (21 vs 41 days, P = 0.03). CONCLUSION: Because of the short hospital stay, the high clinical success rate, and the low adverse event rate compared to PCD, EUS-AD has potential as a first-line treatment for liver abscess.