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This study presented an automatic shoreline extraction method from synthetic aperture radar (SAR) imagery using a semantic image segmentation model, DeepLab-v3+. Shorelines extracted from optical satellite images were employed as ground truth. More than 130,000 pairs of labeled images were generated, which substantially enhances the dataset's objectivity for model training. By using different combination of SAR images from beaches with varying characteristics, several models were constructed. These models were then applied to 15 beaches of Japan to validate their accuracy and versatility. The developed machine learning model demonstrates high accuracy in shoreline extraction, particularly when trained with a diverse set of images from various beaches. This versatility is crucial for the model's applicability across different coastal environments, underscoring the importance of incorporating a wide range of beach properties into the training dataset. [ABSTRACT FROM AUTHOR]

Purpose: We describe the clinical findings in a Japanese patient with unilateral traumatic optic neuropathy (TON) who underwent steroid pulse therapy followed by optic canal decompression surgery. The optic nerve function was assessed longitudinally and quantitatively by Goldmann visual fields (GVFs). This was accomplished by measuring the area of each isopter and scotoma, and the findings were compared with the visual acuities recorded during the course of the resolution of the TON. Case Presentation: A 70‐year‐old man suffered from TON in his left eye after falling from a 3 m cliff. On examination at the Saitama Medical University Hospital, his decimal best corrected visual acuity (BCVA) in his left eye was 0.2. Computed tomography revealed a fracture of the lateral wall of the left orbit, but no obvious optic canal fracture was observed. Steroid pulse therapy was started, and optic nerve decompression surgery was performed. After steroid administration, there was a slight improvement in the visual acuity, and a response in the I/3e isopter was present (area 17.76 deg2). However, the V/4e area decreased from 539.35 to 359.36 deg2. Three days after the optic canal decompression surgery, the decimal visual acuity improved to 0.6, and the V/4e area and I/3e area increased to 1122.52 and 46.88 deg2, respectively. Postoperatively, there was a marked improvement in the size of the GVFs that corresponded to the improved visual acuity. The visual acuity of the left eye was 0.8 after 6 months, and the GVF was still not completely normal. Conclusions: Our findings showed the course of recovery of the visual acuity and visual field in an eye with TON. The quantification of GVF was helpful in assessing the course of recovery after the treatments. The new quantitative index of the GVFs may be helpful in evaluating the effectiveness of treatments for optic nerve disorders. [ABSTRACT FROM AUTHOR]

Background/Aims: Hepatobiliary scintigraphy (HBS) is used to evaluate bile excretion. This study aimed to evaluate biliary excretion during endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) using HBS. Methods: We retrospectively evaluated 78 consecutive patients with malignant extrahepatic biliary obstruction, who underwent HBS after EUS-HGS between April 2015 and July 2022. The peak time and decay rate were scored with 0, 1, or 2 points based on thresholds of 20 and 35 minutes, and 10% and 50%, respectively. A total score of 4 or 3 was considered indicative of good bile excretion, whereas scores of 2, 1, or 0 indicated poor bile excretion. Results: The good and poor bile excretion groups included 40 and 38 cases, respectively. The group with good bile excretion had a significantly longer time to recurrent biliary obstruction compared to the poor bile excretion group (not reached vs. 124 days, p=0.026). Multivariate analysis identified the site of obstruction as a significant factor influencing good bile excretion (odds ratio, 3.39; 95% confidence interval, 1.01–11.4, p=0.049), with superior bile excretion observed in cases involving upper biliary obstruction compared to middle or lower biliary obstruction. Conclusions: In patients with malignant biliary obstruction who underwent HGS, the site of obstruction is significantly associated with stent patency. [ABSTRACT FROM AUTHOR]

Background/Aims: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a highly accurate method for diagnosing pancreatic neuroendocrine tumors (PNETs); however, some PNETs are difficult to diagnose. Recently, the efficacy of needle-based confocal laser endomicroscopy (nCLE) in diagnosing solid pancreatic masses has been reported. However, the efficacy of nCLE in the diagnosis of PNETs remains unknown and only a small number of cases have been reported. Hence, this study aimed to evaluate the efficacy of nCLE in the diagnosis of PNETs. Methods: This single-center retrospective study evaluated 30 consecutive patients with suspected PNETs on contrast-enhanced computed tomography, who consented to nCLE combined with EUS-FNA and were diagnosed using EUS-FNA or surgical resection. The diagnostic criteria for PNETs using nCLE were based on the nesting and trabecular and glandular arrangement of tumor cell clusters surrounded by capillary vessels and fibrosis, as reported in previous studies. Results: The diagnosis using nCLE was classified into three categories: misdiagnosis in three cases (10%), non-diagnostic in six cases (20%), and diagnostic in 21 cases (70%). nCLE was able to diagnose PNET in one of the two cases with inconclusive EUS-FNA. Conclusions: Although further development of the resolution and optimization of the diagnostic criteria are required, nCLE may constitute a useful diagnostic option in cases of inconclusive EUS-FNA for PNETs. [ABSTRACT FROM AUTHOR]

An enantioselective addition reaction for the construction of 1,3‐nonadjacent stereogenic centers is developed by means of a chiral strong Brønsted base catalyst. The chiral sodium ureate catalyst efficiently promoted the reaction of α‐thioacetamides as less acidic pronucleophiles with vinyl sulfones having a variety of α‐substituents including aryl, alkyl and halo groups, and α‐phenylacrylates, accomplishing the construction of various 1,3‐nonadjacent stereogenic centers in highly diastereo‐ and enantioselective manners. This is a rare example of the construction of 1,3‐nonadjacent stereogenic centers with less acidic pronucleophiles. In addition, the application of Michael acceptors having various types of α‐substituents in a single catalyst system is achieved for the first time, demonstrating the utility of the present catalyst system for the construction of 1,3‐nonadjacent stereogenic centers. [ABSTRACT FROM AUTHOR]

Objectives: Endoscopic ultrasound‐guided fine‐needle aspiration and fine‐needle biopsy (EUS‐FNA/FNB) is not fully established as a pathological sampling tool for gallbladder lesions due to limited evidence. We therefore aimed to clarify the effectiveness and safety of this procedure in a large‐population cohort. Methods: This study retrospectively evaluated the diagnostic yield of EUS‐FNA/FNB for accurately differentiating between benign and malignant gallbladder lesions. Puncture targets included the gallbladder mass, lymph node, and liver mass. Adverse events and factors associated with diagnostic accuracy were analyzed as well. Results: In 187 patients with gallbladder lesions undergoing EUS‐FNA/FNB, 18 benign lesions and 169 malignant lesions were identified. Overall sampling adequacy was 98% (184/187). The diagnostic accuracy of EUS‐FNA/FNB was 97% (182/187), sensitivity was 97% (164/169), and specificity was 100% (18/18). A single postprocedural complication (minor bleeding) was recorded in one patient. In the 169 cases of malignancy, 203 sites were punctured for pathological sampling of the primary mass (n = 94), lymph node (n = 79), and metastatic liver mass (n = 30). No significant difference was found for diagnostic accuracy among the puncture sites (P = 0.70). In cases having specimens obtained from the primary mass, the accuracy of those targeting liver invasion sites was significantly higher than that of other sites (98% vs. 83%, P < 0.01). Conclusion: EUS‐FNA/FNB demonstrated clinical usefulness and safety for the pathological diagnosis of gallbladder lesions, with high diagnostic yield and a low incidence of adverse events. Targeting the site of liver infiltration may improve the diagnostic rate of EUS‐FNA/FNB in the primary mass. [ABSTRACT FROM AUTHOR]

Tract dilation is one of the most difficult stages of endoscopic ultrasound‐guided hepaticogastrostomy (EUS‐HGS), especially for beginners. To overcome this problem, we applied a special dedicated dilator. Herein, we retrospectively evaluate the safety and usefulness of a novel drill dilator in EUS‐HGS. This single‐center retrospective study included 20 consecutive patients who underwent EUS‐HGS with a novel drill dilator. The tip is 0.77 mm, and it becomes 7F at 3 cm from tip. The track is dilated to 7F by simple clockwise rotation. The technical success rate of both initial tract dilation and stent placement was 20/20 (100%). No cases required additional dilation such as balloon or electric cautery. In 13/20 cases (65.0%), EUS‐HGS was performed by beginner endoscopists. Median time required for dilation was 62.5 s (range, 30–144 s). Median procedure time was 13 min (range, 7–25 min). Early adverse events were two cases of mild fever. There was no bile leakage or bleeding. The novel drill dilator appears to be safe and useful for EUS‐HGS. As it is not necessary to press the device strongly, there is no pushback during dilation and the scope position is stable. These characteristics facilitate EUS‐HGS even for beginners. This device may enable the further development and increased dissemination of EUS intervention. [ABSTRACT FROM AUTHOR]