Approximately 60% of pancreatic cancers occur in the pancreatic head and may present as obstructive jaundice due to bile duct invasion. Obstructive jaundice often leads to poor general conditions and acute cholangitis, interfering with surgery and chemotherapy and requiring biliary drainage. The first choice of treatment for biliary drainage is the endoscopic transpapillary approach. In unresectable tumors, self-expandable metal stents (SEMSs) are most commonly used and are classified into uncovered and covered SEMSs. Recently, antireflux metal stents and large- or small-diameter SEMSs have become commercially available, and their usefulness has been reported. Plastic stents are infrequently used in patients with resectable biliary obstruction; however, owing to the recent trend in preoperative chemotherapy, SEMSs are frequently used because of the long time to recurrent biliary obstruction. Endoscopic ultrasound-guided biliary drainage (EUS-BD) is often performed in patients who are not eligible for the transpapillary approach, and favorable outcomes have been reported. Different EUS-BD techniques and specialized stents have been developed and can be safely used in high-volume centers. The indications for EUS-BD are expected to further expand in the future.

Background/Aims: Pathological evaluation is crucial for diagnosing biliary lesions and determining appropriate treatment strategies. However, tissue sampling via the transpapillary route can be difficult. In this study, we aimed to assess the efficacy and safety of a novel tapered-tip sheath system for tissue sampling from biliary strictures. Methods: This single-center, randomized, parallel-group clinical trial included patients aged 20 to 85 years admitted to Kyoto University Hospital for biliary strictures. The patients were randomly assigned (1:1) to a new or conventional method group. The primary outcome was technical success of biopsy at the target bile duct using the assigned method, as determined in accordance with the intention-to-treat principle. Adverse events were assessed in all eligible patients. Results: Fifty-six patients were assessed for eligibility between September 2020 and March 2023; 50 patients were enrolled. The patients were randomly divided into the new (n=25) method group and the conventional (n=25) method group. Technical success was achieved in 96.0% (24/25) and 48.0% (12/25) of patients in the new and conventional method groups, respectively (risk ratio, 2.00; 95% confidence interval [CI], 1.32 to 3.03; risk difference, 48.0%; 95% CI, 27.0% to 69.0%; p<0.001). Adverse events occurred in 4.0% (1/25) and 36.0% (9/25) of patients in the new and conventional method groups, respectively (risk ratio, 0.11; 95% CI, 0.02 to 0.81; risk difference, –32.0%; 95% CI, –52.3% to –11.7%; p=0.005). Conclusions The novel tapered-tip sheath system is a promising option for precisely and safely delivering biopsy forceps to target sites, thereby facilitating the diagnosis of biliary strictures.

Background: No studies have compared balloon-assisted endoscope-guided endoscopic retrograde cholangiopancreatography (BAE-ERCP) and endoscopic ultrasonography-guided biliary drainage (EUS-BD) for emergent treatment of acute cholangitis (AC) in patients with upper gastrointestinal surgically altered anatomy (SAA). Methods: This study retrospectively evaluated consecutive patients who underwent emergent BAE-ERCP or EUS-BD for AC with SAA between January 2020 and March 2024. Technical success, clinical success, procedure time, and adverse events (AEs) were compared between the two groups. Results: This study included 23 patients in the BAE-ERCP group and 14 patients in the EUS-BD group. Technical success and clinical success rates did not significantly differ between the two groups (88% vs. 100%, P = 0.51 and 95% vs. 93%, P = 0.66). Similarly, the rate of AEs was comparable between the two groups (4% vs. 14%, P = 0.54). The median procedure time was significantly shorter in the EUS-BD group than in the BAE-ERCP group (32.5 [interquartile range; IQR, 28.8–52.5] minutes vs. 70.0 [IQR, 60.0–90.0] minutes, P < 0.01). In cases with grade 2 or 3 cholangitis, the rates of technical success, clinical success, and AEs did not significantly differ between the two groups. However, the median procedure time was significantly shorter in the EUS-BD group than in the BAE-ERCP group (32.5 [IQR, 28.8–52.5] minutes vs. 70 [IQR, 56.3–90.0] minutes, P < 0.01). Conclusion While both BAE-ERCP and EUS-BD can be performed safely and effectively in patients with AC and SAA, the procedure time is significantly shorter with EUS-BD than with BAE-ERCP.

Background: Endoscopic ultrasound-guided gallbladder drainage (EUS-GBD) has been recognized as an effective treatment for patients at high risk for surgery. An antimigration metal stent with tapered thin delivery system has recently been developed. The aims of this study were to evaluate the feasibility, safety, and longterm outcomes of EUS-GBD using the new metal stent. Methods: Between April 2017 and March 2020, 21 patients with acute cholecystitis unsuitable for cholecystectomy underwent EUS-GBD using the metal stent. The stent was 6 mm in diameter and 6 cm in length, with a large flare at both ends for antimigration, and mounted in a 7.5 Fr delivery catheter, which requires no dilation devices. We retrospectively evaluated clinical and technical success, adverse events, and stent patency. Results: The technical and clinical success rates of EUS-GBD using the metal stent were 95.2% and 100%, respectively. For 75% of the patients, metal stents could be placed without dilatation of the needle tract. These patients had significantly shorter procedure time (23.6 ± 9.8 min) than patients requiring needle tract dilatation (38.4 ± 17.1 min; P = 0.036). The median follow-up periods were 336 days (interquartile range [IQR] 152–919 days) and 1,135 days (IQR 1,009–1,675 days) for all and alive patients, respectively. No adverse events or recurrence of cholecystitis due to stent occlusion that occurred in any patient at follow-up was observed. Conclusion In conclusion, EUS-GBD using the newly designed metal stent showed excellent safety and longterm outcomes, and may be suitable as an alternative treatment in patients who are unsuitable for cholecystectomy.

Background: No studies have compared balloon-assisted endoscope-guided endoscopic retrograde cholangiopancreatography (BAE-ERCP) and endoscopic ultrasonography-guided biliary drainage (EUS-BD) for emergent treatment of acute cholangitis (AC) in patients with upper gastrointestinal surgically altered anatomy (SAA). Methods: This study retrospectively evaluated consecutive patients who underwent emergent BAE-ERCP or EUS-BD for AC with SAA between January 2020 and March 2024. Technical success, clinical success, procedure time, and adverse events (AEs) were compared between the two groups. Results: This study included 23 patients in the BAE-ERCP group and 14 patients in the EUS-BD group. Technical success and clinical success rates did not significantly differ between the two groups (88% vs. 100%, P = 0.51 and 95% vs. 93%, P = 0.66). Similarly, the rate of AEs was comparable between the two groups (4% vs. 14%, P = 0.54). The median procedure time was significantly shorter in the EUS-BD group than in the BAE-ERCP group (32.5 [interquartile range; IQR, 28.8–52.5] minutes vs. 70.0 [IQR, 60.0–90.0] minutes, P < 0.01). In cases with grade 2 or 3 cholangitis, the rates of technical success, clinical success, and AEs did not significantly differ between the two groups. However, the median procedure time was significantly shorter in the EUS-BD group than in the BAE-ERCP group (32.5 [IQR, 28.8–52.5] minutes vs. 70 [IQR, 56.3–90.0] minutes, P < 0.01). Conclusion While both BAE-ERCP and EUS-BD can be performed safely and effectively in patients with AC and SAA, the procedure time is significantly shorter with EUS-BD than with BAE-ERCP.

Background: Endoscopic ultrasound-guided gallbladder drainage (EUS-GBD) has been recognized as an effective treatment for patients at high risk for surgery. An antimigration metal stent with tapered thin delivery system has recently been developed. The aims of this study were to evaluate the feasibility, safety, and longterm outcomes of EUS-GBD using the new metal stent. Methods: Between April 2017 and March 2020, 21 patients with acute cholecystitis unsuitable for cholecystectomy underwent EUS-GBD using the metal stent. The stent was 6 mm in diameter and 6 cm in length, with a large flare at both ends for antimigration, and mounted in a 7.5 Fr delivery catheter, which requires no dilation devices. We retrospectively evaluated clinical and technical success, adverse events, and stent patency. Results: The technical and clinical success rates of EUS-GBD using the metal stent were 95.2% and 100%, respectively. For 75% of the patients, metal stents could be placed without dilatation of the needle tract. These patients had significantly shorter procedure time (23.6 ± 9.8 min) than patients requiring needle tract dilatation (38.4 ± 17.1 min; P = 0.036). The median follow-up periods were 336 days (interquartile range [IQR] 152–919 days) and 1,135 days (IQR 1,009–1,675 days) for all and alive patients, respectively. No adverse events or recurrence of cholecystitis due to stent occlusion that occurred in any patient at follow-up was observed. Conclusion In conclusion, EUS-GBD using the newly designed metal stent showed excellent safety and longterm outcomes, and may be suitable as an alternative treatment in patients who are unsuitable for cholecystectomy.

Background/Aims: Pathological evaluation is crucial for diagnosing biliary lesions and determining appropriate treatment strategies. However, tissue sampling via the transpapillary route can be difficult. In this study, we aimed to assess the efficacy and safety of a novel tapered-tip sheath system for tissue sampling from biliary strictures. Methods: This single-center, randomized, parallel-group clinical trial included patients aged 20 to 85 years admitted to Kyoto University Hospital for biliary strictures. The patients were randomly assigned (1:1) to a new or conventional method group. The primary outcome was technical success of biopsy at the target bile duct using the assigned method, as determined in accordance with the intention-to-treat principle. Adverse events were assessed in all eligible patients. Results: Fifty-six patients were assessed for eligibility between September 2020 and March 2023; 50 patients were enrolled. The patients were randomly divided into the new (n=25) method group and the conventional (n=25) method group. Technical success was achieved in 96.0% (24/25) and 48.0% (12/25) of patients in the new and conventional method groups, respectively (risk ratio, 2.00; 95% confidence interval [CI], 1.32 to 3.03; risk difference, 48.0%; 95% CI, 27.0% to 69.0%; p<0.001). Adverse events occurred in 4.0% (1/25) and 36.0% (9/25) of patients in the new and conventional method groups, respectively (risk ratio, 0.11; 95% CI, 0.02 to 0.81; risk difference, –32.0%; 95% CI, –52.3% to –11.7%; p=0.005). Conclusions The novel tapered-tip sheath system is a promising option for precisely and safely delivering biopsy forceps to target sites, thereby facilitating the diagnosis of biliary strictures.

BACKGROUND: Motion sickness is a common transportation issue worldwide. Vestibular dysfunction has been reported to be a key etiology of motion sickness. However, there are limited technologies for alleviating motion sickness. METHODS: The most appropriate frequency (Hz) and level (dBZ) of pure tone for modulation of vestibular function were determined by an ex vivo study using murine utricle explants. The preventive effects of the selected pure tone on motion sickness were then confirmed by using a beam balance test in mice. The alleviating effects of pure tone on motion sickness induced by a swing, driving simulator or real car were objectively assessed by using posturography and electrocardiography (ECG) and were subjectively assessed by using the Motion Sickness Assessment Questionnaire (MSAQ) in humans. RESULTS: The effect of short-term (≤5 min) exposure to a pure tone of 80-85 dBZ (= 60.9-65.9 dBA) at 100 Hz on motion sickness was investigated in mice and humans. A mouse study showed a long-lasting (≥120 min) alleviative effect on shaking-mediated exacerbated beam test scores by 5-min exposure to a pure tone of 85 dBZ at 100 Hz, which was ex vivo determined as a sound activating vestibular function, before shaking. Human studies further showed that 1-min exposure to a pure tone of 80-85 dBZ (= 60.9-65.9 dBA) at 100 Hz before shaking improved the increased envelope areas in posturography caused by the shakings of a swing, a driving simulator and a vehicle. Driving simulator-mediated activation of sympathetic nerves assessed by the heart rate variable (HRV) and vehicle-mediated increased scores of the MSAQ were improved by pure tone exposure before the shaking. CONCLUSION: Since the exacerbated results of posturography and HRV reflect shaking-mediated imbalance and autonomic dysfunction, respectively, the results suggest that the imbalance and autonomic dysregulation in motion sickness could be improved by just 1-min exposure to a pure tone with daily exposable sound pressure levels. TRIAL REGISTRATION Registration number: UMIN000022413 (2016/05/23-2023/04/19) and UMIN000053735 (2024/02/29-present).
Motion Sickness/therapy* ; Animals ; Mice ; Humans ; Male ; Adult ; Female ; Sound ; Middle Aged ; Young Adult ; Mice, Inbred C57BL