Safety and efficacy of novel oblique-viewing scope for B2-endoscopic ultrasound-guided hepaticogastrostomy.

Background/Aims: Endoscopic ultrasound (EUS)-guided hepaticogastrostomy (EUS-HGS) performed at the intrahepatic bile duct segment 3 (B3) is widely used for biliary drainage. Although performing post-puncture procedures is easier in the intrahepatic bile duct segment 2 (B2) when using a conventional oblique-viewing (OV) EUS scope, this method may cause transesophageal puncture and severe adverse events. We evaluated the safety and efficacy of B2 puncture using a novel OV-EUS scope. Methods: In this single-center retrospective study, we prospectively enrolled and collected data from 45 patients who consecutively underwent EUS-HGS procedures with a novel OV-EUS scope between September 2021 and December 2022 at our cancer center. Results: The technical success rates of B2-EUS-HGS and EUS-HGS were 93.3% (42/45) and 97.8% (44/45), respectively. The early adverse event rate was 8.9% (4/45) with no cases of scope changes or transesophageal punctures. The median procedure time was 13 minutes (range, 5-30). Conclusions: B2-EUS-HGS can be performed safely with the novel EG-740UT (Fujifilm) OV-scope without transesophageal puncture and with a high success rate. B2-EUS-HGS using this novel OV scope may be the preferred strategy for EUS-HGS.

Transluminal antegrade drill dilation technique for hepaticojejunostomy stricture with cholangioscopic evaluation (with video).

Background and study aims Balloon dilation and plastic stent deployment have been performed as hepaticojejunostomy stricture (HJS) treatment techniques under endoscopic ultrasound guidance (EUS). Although these techniques have shown favorable clinical results, the treatment period can be long because stent deployment is required. In addition, HJS may recur even after treatment because the scar tissue itself remains. To overcome these challenges, we developed an EUS-guided antegrade drill dilation technique for treating HJS. The aim of this study was to evaluate the technical feasibility and safety of this technique in terms of the pre- and post-cholangioscopic findings. Patients and methods This retrospective study included consecutive patients whose conditions were complicated with symptomatic HJS between November 2022 and February 2023. Transluminal antegrade drill dilation (TAD) using a novel drill dilator was attempted within 14 days after EUS-guided hepaticogastrostomy (HGS). HJS was diagnosed with cholangioscopy before TAD, and resolution was evaluated after TAD using cholangioscopy. Results TAD was attempted at approximately 11 days after EUS-HGS. The cholangioscope was inserted successfully in all patients after this procedure. Cholangioscopy revealed stricture without evidence of malignancy in 19 patients. In the remaining three patients, stricture was not observed and these patients underwent stent exchange rather than TAD. Among the 19 patients, passage of the guidewire across the HJS into the intestine was unsuccessful in four patients, and the technical success rate for this procedure was 78.9%. TAD was successful in all 15 patients in whom passage of the guidewire was achieved. Conclusions In conclusion, TAD appears to be technically feasible and safe.

Clinical utility of endoscopic ultrasound-guided tissue acquisition for comprehensive genomic profiling of patients with biliary tract cancer, especially with intrahepatic cholangiocarcinoma.

BACKGROUND/AIMS: Endoscopic ultrasound-guided tissue acquisition (EUS-TA) is a standard diagnostic method for biliary tract cancer (BTC), and samples obtained in this manner may be used for comprehensive genomic profiling (CGP). This study evaluated the utility of EUS-TA for CGP in a clinical setting and determined the factors associated with the adequacy of CGP in patients with BTC. METHODS: CGP was attempted for 105 samples from 94 patients with BTC at the Aichi Cancer Center, Japan, from October 2019 to April 2022. RESULTS: Overall, 77.1% (81/105) of the samples were adequate for CGP. For 22-G or 19-G fine-needle biopsy (FNB), the sample adequacy was 85.7% (36/42), which was similar to that of surgical specimens (94%, p=0.45). Univariate analysis revealed that 22-G or larger FNB needle usage (86%, p=0.003), the target primary lesions (88%, p=0.015), a target size ≥30 mm (100%, p=0.0013), and number of punctures (90%, p=0.016) were significantly positively associated with CGP sample adequacy. CONCLUSIONS: EUS-TA is useful for CGP tissue sampling in patients with BTC. In particular, the use of 22-G or larger FNB needles may allow for specimen adequacy comparable to that of surgical specimens.

Diagnostic performance and safety of endoscopic ultrasound-guided fine-needle aspiration/biopsy for gallbladder lesions.

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.

Safety of endoscopic ultrasound-guided hepaticogastrostomy in patients with malignant biliary obstruction and ascites.

BACKGROUND/AIMS: Endoscopic ultrasound (EUS)-guided hepaticogastrostomy (EUS-HGS) is useful for patients with biliary cannulation failure or inaccessible papillae. However, it can lead to serious complications such as bile peritonitis in patients with ascites; therefore, development of a safe method to perform EUS-HGS is important. Herein, we evaluated the safety of EUS-HGS with continuous ascitic fluid drainage in patients with ascites. METHODS: Patients with moderate or severe ascites who underwent continuous ascites drainage, which was initiated before EUS-HGS and terminated after the procedure at our institution between April 2015 and December 2022, were included in the study. We evaluated the technical and clinical success rates, EUS-HGS-related complications, and feasibility of re-intervention. RESULTS: Ten patients underwent continuous ascites drainage, which was initiated before EUS-HGS and terminated after completion of the procedure. Median duration of ascites drainage before and after EUS-HGS was 2 and 4 days, respectively. Technical success with EUS-HGS was achieved in all 10 patients (100%). Clinical success with EUS-HGS was achieved in 9 of the 10 patients (90 %). No endoscopic complications such as bile peritonitis were observed. CONCLUSION: In patients with ascites, continuous ascites drainage, which is initiated before EUS-HGS and terminated after completion of the procedure, may prevent complications and allow safe performance of EUS-HGS.

Relationship between imaging parameters and distortion in magnetic resonance images for gamma knife treatment planning.

In magnetic resonance imaging (MRI), it is necessary to reduce image distortion as much as possible because it suppresses the increase in the planning target volume. This study investigated the relationship between imaging parameters and image distortion when using G-frames. The images were obtained using a 1.5-T MRI system with a 09-101 Pro-MRI phantom. Image distortion was measured by changing the RF pulse mode, gradient mode, asymmetric echo, and bandwidth (BW). The image distortion was increased in the high RF mode than in the Normal mode. The image distortion increased in the following order: Whisper â‰¦ Normal < Fast in the different gradient modes. The image distortion increased in the following order: Without â‰¦ Weak < Strong in the different asymmetric echo modes. The image distortion increased in the following order: 300 Hz/pixel > 670 Hz/pixel â‰§ REF (150 Hz/pixel) in the different Bw. The relationship between parameters and image distortion was clarified in this study when G-frames were used for gamma knife therapy. There is had relationship between the parameters causing variation in the gradient magnetic field and image distortion. Therefore, these parameters should be adjusted to minimize distortion.

Anhydrous proton conductor consisting of protamine-monododecyl phosphate composite with self-assembled structure.

We prepared a protamine-monododecyl phosphate composite by mixing protamine (P) and a monododecyl phosphate (MDP). This P-MDP composite formed an acid-base complex by the electrostatic interaction between cationic protamine and the negatively charged phosphate group. Additionally, according to the X-ray diffraction (XRD) measurements, the composite formed a self-assembled lamellar structure with an interaction between the long alkyl chains of MDP. As a result, the P-MDP composite showed the proton conductivity of 9.5 × 10-4 S cm-1 at 120-130 °C under anhydrous conditions. Furthermore, the activation energy of the proton conduction of the P-MDP composite was approximately 0.18 eV. These results suggested that the proton conduction of the P-MDP composite was based on an anhydrous proton conductive mechanism. In contrast, the anhydrous proton conduction of the P-methanediphosphonic acid (MP) composite, which did not form the self-assembled lamellar structure, was ca. 3 × 10-5 S cm-1 at 120-130 °C and this value was one order of magnitude lower than that of the P-MDP composite. Therefore, the two-dimensional self-assembled proton conductive pathway of the P-MDP composite plays a role in the anhydrous proton conduction.

The role of needle-based confocal laser endoscopy in the diagnosis of pancreatic neuroendocrine tumors.

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.

Safety and feasibility of opening window fistulotomy as a new precutting technique for primary biliary access in endoscopic retrograde cholangiopancreatography.

BACKGROUND/AIMS: Post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) is the most common and serious complication of endoscopic retrograde cholangiopancreatography. To prevent this event, a unique precutting method, termed opening window fistulotomy, was performed in patients with a large infundibulum as the primary procedure for biliary cannulation, whereby a suprapapillary laid-down H-shaped incision was made without touching the orifice. This study aimed to assess the safety and feasibility of this novel technique. METHODS: One hundred and ten patients were prospectively enrolled in this study. Patients with a papillary roof size ≥10 mm underwent opening window fistulotomy for primary biliary access. In addition, the incidence of complications and success rate of biliary cannulation were evaluated. RESULTS: The median size of the papillary roof was 6 mm (range, 3-20 mm). Opening window fistulotomy was performed in 30 patients (27.3%), none of whom displayed PEP. Duodenal perforation was recorded in one patient (3.3%), which was resolved by conservative treatment. The cannulation rate was high (96.7%, 29/30 patients). The median duration of biliary access was 8 minutes (range, 3-15 minutes). CONCLUSION: Opening window fistulotomy demonstrated its feasibility for primary biliary access by achieving great safety with no PEP complications and a high success rate for biliary cannulation.

Relationship Between Nonsmoothness in Adversarial Training, Constraints of Attacks, and Flatness in the Input Space.

Adversarial training (AT) is a promising method to improve the robustness against adversarial attacks. However, its performance is not still satisfactory in practice compared with standard training. To reveal the cause of the difficulty of AT, we analyze the smoothness of the loss function in AT, which determines the training performance. We reveal that nonsmoothness is caused by the constraint of adversarial attacks and depends on the type of constraint. Specifically, the L∞ constraint can cause nonsmoothness more than the L2 constraint. In addition, we found an interesting property for AT: the flatter loss surface in the input space tends to have the less smooth adversarial loss surface in the parameter space. To confirm that the nonsmoothness causes the poor performance of AT, we theoretically and experimentally show that smooth adversarial loss by EntropySGD (EnSGD) improves the performance of AT.

Artificial intelligence using deep learning analysis of endoscopic ultrasonography images for the differential diagnosis of pancreatic masses.

BACKGROUND : There are several types of pancreatic mass, so it is important to distinguish between them before treatment. Artificial intelligence (AI) is a mathematical technique that automates learning and recognition of data patterns. This study aimed to investigate the efficacy of our AI model using endoscopic ultrasonography (EUS) images of multiple types of pancreatic mass (pancreatic ductal adenocarcinoma [PDAC], pancreatic adenosquamous carcinoma [PASC], acinar cell carcinoma [ACC], metastatic pancreatic tumor [MPT], neuroendocrine carcinoma [NEC], neuroendocrine tumor [NET], solid pseudopapillary neoplasm [SPN], chronic pancreatitis, and autoimmune pancreatitis [AIP]). METHODS : Patients who underwent EUS were included in this retrospective study. The included patients were divided into training, validation, and test cohorts. Using these cohorts, an AI model that can distinguish pancreatic carcinomas from noncarcinomatous pancreatic lesions was developed using a deep-learning architecture and the diagnostic performance of the AI model was evaluated. RESULTS : 22 000 images were generated from 933 patients. The area under the curve, sensitivity, specificity, and accuracy (95 %CI) of the AI model for the diagnosis of pancreatic carcinomas in the test cohort were 0.90 (0.84-0.97), 0.94 (0.88-0.98), 0.82 (0.68-0.92), and 0.91 (0.85-0.95), respectively. The per-category sensitivities (95 %CI) of each disease were PDAC 0.96 (0.90-0.99), PASC 1.00 (0.05-1.00), ACC 1.00 (0.22-1.00), MPT 0.33 (0.01-0.91), NEC 1.00 (0.22-1.00), NET 0.93 (0.66-1.00), SPN 1.00 (0.22-1.00), chronic pancreatitis 0.78 (0.52-0.94), and AIP 0.73 (0.39-0.94). CONCLUSIONS : Our developed AI model can distinguish pancreatic carcinomas from noncarcinomatous pancreatic lesions, but external validation is needed.

Novel drill dilator facilitates endoscopic ultrasound-guided hepaticogastrostomy.

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.

[A Case of Submucosal Invasion(SM2)Gastric Cancer with Peritoneal Dissemination Three Years after Surgery].

The patient is a 90-year-old man. Three years and 3 months after laparoscopic distal gastrectomy for early gastric cancer, pT1b(SM2)pN1M0, Stage Ⅰ, the patient visited our hospital with abdominal pain, and a large amount of ascites and stenosis of transverse colon were pointed out. He underwent a right hemicolectomy under laparotomy. Histopathologically, it was diagnosed as peritoneal recurrence of previous gastric cancer. Postoperatively, he died of aspiration pneumonia. As for the cause of death after surgery of early gastric cancer, there are many causes of death from other diseases and few from primary malignancy. Furthermore, recurrence of peritoneal dissemination is extremely rare and considered to be a valuable case.

[A Case of Perforation at the Stump of Descending Colon after Hartmann's Operation Performed after Transverse Colostomy].

A 77-year-old man with complaining of anemia and abdominal pain was admitted to our hospital. An abdominal computed tomography showed the sigmoid colon tumor with bowel obstruction. Laparoscopic transverse colostomy was performed to release intestinal obstruction. After first operation, he was diagnosed the sigmoid colon cancer: cT4b(bladder), cN0, cM0, and cStage Ⅱc. Radical laparoscopic operation(Hartmann's operation)was performed. On the 4th postoperative day, fecal juice was discharged from the abdominal drain placed in the Douglas fossa, so emergency laparotomy was performed. The intraoperative findings showed perforation in the blind end of the descending colon. The descending colon was resected from a site approximately 5 cm anal side of the transverse colostomy to the blind end. It was thought that perforation occurred due to an increase in internal pressure in the residual intestinal tract after Hartmann's surgery without blood flow disorder. We believe that further attention is required to the management of residual intestinal tract at the blind end for the obstructive colorectal cancer.

[Association between the Preoperative Nutritional Index and Postoperative Complications/Prognosis in Older Adults with Gastric Cancer Who Have Undergone a Gastrectomy].

We analyzed the relationship between preoperative nutritional indices and postoperative complications/prognoses in patients with pStage Ⅰ and Ⅱ gastric cancer aged ≥75 years who had undergone gastrectomy in our hospital. Between January 2012 and March 2021, a total of 79 cases of pStage Ⅰ and Ⅱ gastric cancer were examined in individuals aged ≥75 years who had undergone gastrectomy. We investigated the correlation between short- and long-term outcomes and the nutritional index. CONUT, GPS, and GNRI were employed as indicators of nutritional status. CONUT and GPS showed associations with postoperative complications and an extended postoperative hospital stay, whereas GNRI did not exhibit such associations. Among the patients, 7 deaths were attributed to primary diseases, whereas 16 deaths were attributed to other diseases. No correlation was found between survival rate and preoperative nutritional status. Conclusions: There were minimal cancer recurrences among older adults with gastric cancer who had undergone gastrectomy. Although preoperative nutritional status was associated with postoperative complications, it did not show an association with prognosis.

B2 puncture with forward-viewing EUS simplifies EUS-guided hepaticogastrostomy (with video).

Background and Objectives: EUS-guided hepaticogastrostomy (EUS-HGS) is in widespread use; however, there are few dedicated devices. The B2 route is technically easier than the B3 route for guidewire insertion, dilation, and stenting but if performed with conventional oblique-viewing (OV) EUS, B2 puncture can cause transesophageal puncture and severe adverse events. The aim of this study was to assess the efficacy of forward-viewing (FV) EUS, which we have developed to improve safety for B2 puncture in EUS-HGS (B2-EUS-HGS). Patients and Methods: This single-center retrospective study included 61 consecutive patients who underwent B2-EUS-HGS with FV between February 2020 and March 2021 at Aichi Cancer Center, Japan. The patients were prospectively enrolled, and clinical data were retrospectively collected for these 61 cases. Results: The overall technical success rate of EUS-HGS was 98.3% (60/61). The rate of EUS-HGS with FV was 95.0% (58/61) after three cases converted to OV, and that of B2-EUS-HGS with FV was 88.5% (54/61). The early adverse event rate was 6.5% (4/61). There were no instances of transesophageal puncture. Median procedure time was 24 min (range, 8-70), and no patient required cautery dilation. Conclusions: B2-EUS-HGS can be performed safely using FV, without transesophageal puncture, and supportability of the device is improved as FV is coaxial with the guidewire. FV was efficacious in B2-EUS-HGS, which shows promise for clinical application in the future.

Endoscopic bilateral revision after metal stent deployment for hepatic hilar obstruction using molting technique (with videos).

Background: After multiple uncovered self-expandable metal stent (UCSEMS) deployments, endoscopic revision becomes complex and potentially challenging. A novel stent delivery system with a dilation function has recently been developed in Japan. This study evaluated the technical feasibility of this device for patients with unresectable malignant hilar biliary obstruction (MHO) after multiple UCSEMS deployments. Method: Participants comprised consecutive patients with unresectable MHO who had undergone multiple UCSEMS deployments and required endoscopic revision for the right or left hepatic bile ducts, as decided by cholangiography under endoscopic retrograde cholangiopancreatography (ERCP) guidance. Results: A total of 14 patients requiring endoscopic revision of right and left hepatic bile ducts were enrolled in this study. Among these 14 patients, guidewire insertion through the mesh of previously placed stents failed in 2 patients. As a result, these two patients underwent only unilateral UCSEMS deployment. Because clinical success was not obtained, transmural placement of the UCSEMS under Endoscopic Ultrasound (EUS) guidance to the segment of the liver not being drained was performed in those patients. The molting technique was attempted in 12 patients, proving successful in all patients. The technical success rate was therefore 92.8% (12/14). Mean procedure time was 23.2 min. Conclusion: This novel stent delivery system with a dilation function may be useful in endoscopic revision techniques for bilateral UCSEMS deployment.

Preparation of bioplastic consisting of salmon milt DNA.

The microplastic that pollutes the ocean is a serious problem around the world. The bioplastic consisting of biopolymers which is degraded in nature, is one of the strategies to solve this problem. Although the bioplastics consisting of protein, polysaccharide, polylactic acid, etc., have been reported, which consist of DNA, one of the most important materials in the genetic process, have not been reported to the best of our knowledge. In addition, a large amount of DNA-containing materials, such as salmon milts, is discarded as industrial waste around the world. Therefore, we demonstrated the preparation of a bioplastic consisting of salmon milt DNA. The DNA plastic was prepared by the immersion of a DNA pellet in a formaldehyde (HCHO) solution and heating. As a result, the water-stable DNA plastics were obtained at the HCHO concentration of 20% or more. Particularly, the DNA plastic with a 25% HCHO treatment showed water-insoluble, thermally stable, and highly mechanical properties. These are due to the formation of a three-dimensional network via the crosslinking reaction between the DNA chains. In addition, since DNA in plastic possesses the double-stranded structure, these plastics effectively accumulated the DNA intercalator, such as ethidium bromide. Furthermore, the DNA plastics indicated a biodegradable property in a nuclease-containing aqueous solution and the biodegradable stability was able to be controlled by the HCHO concentration. Therefore, salmon milt DNA has shown the potential to be a biodegradable plastic.