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Objectives Methods Results Conclusion Detective flow imaging endoscopic ultrasonography (DFI‐EUS) is a recent imaging modality developed for detecting fine vessels without the need for ultrasound contrast agents. The aim of the present study was to evaluate the utility of DFI‐EUS for solid pancreatic lesions and to compare the diagnostic ability for pancreatic cancer (PC) between DFI‐EUS, directional power Doppler (eFLOW) EUS, and contrast‐enhanced harmonic (CH)‐EUS.Patients with a pancreatic lesion who underwent DFI‐EUS, eFLOW‐EUS, and CH‐EUS between March 2019 and November 2023 were retrospectively enrolled. Final diagnoses were confirmed by pathologic examination of EUS‐guided tissue acquisition and/or resected specimens. Lesions were categorized into the three patterns of poor, mild, and rich vascularity on DFI‐EUS and eFLOW‐EUS, and hypo‐, iso‐, and hypervascular on CH‐EUS. PC was defined as a poor pattern on DFI‐EUS and eFLOW‐EUS, and a hypovascular pattern on CH‐EUS.The final diagnoses of 90 examined tumors were PC (n = 57), inflammatory mass (n = 6), autoimmune pancreatitis (n = 13), neuroendocrine tumor (n = 9), and others (n = 5). The sensitivity, specificity, and accuracy for diagnosis of PC were 93%, 82%, and 88%, respectively, on DFI‐EUS, 97%, 42%, and 77% on eFLOW‐EUS, and 95%, 89%, and 92% on CH‐EUS. The accuracy of DFI‐EUS was significantly superior to eFLOW‐EUS (P = 0.005), but no significant difference was found between DFI‐EUS and CH‐EUS.DFI‐EUS is more sensitive for depicting vasculature than eFLOW‐EUS, and has higher diagnostic sensitivity for PC. Evaluation of vascularity on DFI‐EUS is useful for the differential diagnosis of pancreatic lesions without the need for intravenous contrast agent. [ABSTRACT FROM AUTHOR]

Laparoscopic subtotal cholecystectomy, a bailout surgery for cholecystitis, can result in postoperative bile leakage, so surgical ingenuity is required. An 88‐year‐old woman had pain at the right hypochondrium. Abdominal computed tomography showed swelling of the gallbladder and thickness of the gallbladder wall, leading to diagnosis of mild acute cholecystitis. Percutaneous transhepatic gallbladder drainage was performed to alleviate cholecystitis because the patient was taking antiplatelet medicine. Laparoscopic cholecystectomy was then performed within 72 hours from the onset. The gallbladder was operatively found to be strongly fibrotic, so the procedure was switched to laparoscopic subtotal cystectomy, dissecting the gallbladder at the infundibulum‐cystic duct level. The gallbladder stump was closed with barbed suture and omentopexy was added due to fragility. There was no significant postoperative bile leakage. Additional omentopexy to stump closure in laparoscopic subtotal cholecystectomy was thought to be useful in prevention of postoperative bile leakage. [ABSTRACT FROM AUTHOR]

We investigate the cause of the insertion loss of our holographic switch by determining the relation between the diffraction efficiency and the hologram patterns generated by the control beams. According to the calculation the theoretical insertion loss is 7.4 dB with loss distribution of 0.03 dB under the conditions of a previous experiment. We find that incomplete storage of the interference pattern on the optically addressed spatial light modulator is the strongest factor determining the insertion loss.

We extended the scale of a previously reported holographic switch [Appl. Opt. 34, 8137 (1995)] in which each input is assigned to one of the control light sources to control a large-scale switch with low power. The average losses of the four inputs were 28, 33, 35, and 36 dB. The average cross-talk-to-signal ratio of one of the inputs was -16 dB. Key words: Holographic switching, optical interconnects, spatial light modulator, ferroelectric liquid crystal.

Simulating the positions of output beams under the assumption that a liquid-crystal display acts as a binary phase modulator reveals that the number of the outputs increases almost linearly with the square root of the number of pixels assigned to an input. This result is confirmed by experiments, and it is estimated that 1016 outputs can be obtained when the number of pixels is 700 X 700. Holographic switches with liquid-crystal displays are therefore suitable for large-scale switches. Key words: Holographic switching, liquid-crystal display, computer-generated hologram.

Objectives: Among subepithelial lesions (SELs), gastrointestinal stromal tumors (GISTs) should be identified and surgically treated at an early stage. However, it is difficult to diagnose SELs smaller than 20 mm. In recent years, endoscopic ultrasound (EUS) elastography (EUS-EG) and contrast-enhanced harmonic EUS (CH-EUS) have been reported to be useful for the diagnosis of SELs, although the diagnostic accuracy of a combination of EUS techniques with image enhancement is unknown., Methods: Patients with SELs who underwent EUS-guided tissue acquisition, EUS shear-wave elastography (EUS-SWE), EUS strain elastography (EUS-SE), and CH-EUS from January 2019 to June 2023 were enrolled. To assess the diagnostic accuracy for differentiating GISTs from other SELs, shear-wave velocity on EUS-SWE, the strain ratio on EUS-SE, and vascularity on CH-EUS were determined and their diagnostic accuracies were compared., Results: Forty-three patients were enrolled. When the cut-off value was set at 3.27 m/s, the sensitivity, specificity, and diagnostic accuracy of shear-wave velocity were 28.6%, 86.2%, and 34.9%, respectively. When the cut-off value was set at 3.79, the sensitivity, specificity, and diagnostic accuracy of the strain ratio were 93.1%, 64.3%, and 83.7%, respectively. The sensitivity, specificity, and diagnostic accuracy of CH-EUS were 79.3%, 92.3%, and 83.7%, respectively. When EUS-SE was combined with CH-EUS, the sensitivity and diagnostic accuracy were the highest among binary combinations of image enhancement modalities., Conclusions: EUS-SE and CH-EUS are useful for differentiating GISTs from other SELs. Furthermore, the use of both modalities may further improve the identification of GISTs., Competing Interests: Masayuki Kitano has received honoraria from Olympus Corporation for delivering lectures at conferences and has received research grants from Boston Scientific Corporation and Medico's Hirata Incorporated. The other authors declare no conflict of interest., (© 2024 The Author(s). DEN Open published by John Wiley & Sons Australia, Ltd on behalf of Japan Gastroenterological Endoscopy Society.)

Background and study aims The relative procedural performance of needles for endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNA/B) is unclear. The present study therefore compared six types of 22-gauge FNA/B needles using a bench simulator. Methods Resistance forces during needle puncture and removal, needle tip damage before and after procedure, leakage after puncture of mucinous cyst models, the shape of the puncture surface at the puncture site, amounts of samples extracted, ranges of needle deflection angles, and needle deformation after multiple procedures were compared using six types of needles. Results Maximum resistance forces during puncture and removal were highest for ProCore needles and lowest for Expect needles. None of the needles had damage after puncturing. SharkCore needles showed the highest amount of leakage, whereas FNA needles showed no leakage. The puncture tracts of FNA needles remained in the form of a flap at the puncture site, whereas FNB needles broke off the target material creating a hole. The target material removed was supplemented within the puncture needle. TopGain needles produced significantly larger samples than ProCore, EZShot3 Plus, and Expect needles. FNB needles produced larger and more core samples than FNA needles. EZShot3 Plus needles had the highest range of needle deflection angle using an elevator device and the lowest needle deformation after 20 punctures at full endoscopic angle and a full elevator. Conclusions The performance of the six needles differed in various ways. Understanding the characteristics of each needle may allow for selection of the appropriate needle for each situation., Competing Interests: Conflict of Interest The author M.K. has received honoraria from Olympus Corporation for lectures at conferences and grants from Medico’s Hirata Inc. The remaining authors have no conflicts of interest to declare., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).)

A 93-year-old man presented to our hospital with a fever, abdominal pain, and jaundice. Computed tomography revealed bilateral bile duct dilation, cystic lesions with bile duct communication, and intraluminal solid nodules arising from the bile duct wall. The patient was diagnosed with intraductal papillary neoplasm of the bile duct. Surgery was not performed, considering the patient's age. It was impossible to control cholangitis using conventional endoscopic therapy. We therefore created an access route to the bile duct using endoscopic ultrasound-guided choledochoduodenostomy and inserted a lumen-apposed metal stent. Thereafter, we performed argon plasma coagulation of the tumor in the bile duct, which successfully prevented cholangitis recurrence.