論文

Abstract – Introduction: Superficial duodenal epithelial tumors (SDETs) and non-neoplastic lesions (NNLs) often appear similar on conventional endoscopy, complicating real-time differentiation and leading to frequent biopsies. However, duodenal biopsy is invasive and may hinder subsequent endoscopic resection. We previously developed a diagnostic algorithm using magnified endoscopic examination with image-enhanced endoscopy (IEE-ME) to distinguish SDETs from NNLs. This study aimed to prospectively validate the diagnostic performance of this algorithm in clinical practice. Methods: In this single-center prospective observational study, we evaluated an IEE-ME-based diagnostic algorithm for esophagogastroduodenoscopy. Lesions were classified according to predefined criteria, including superficial structure, white opaque substance, demarcation line, and enlarged marginal epithelium. Endoscopic diagnoses were made immediately by 11 endoscopists with varied experience, who were blinded to the final histopathological diagnoses. The diagnostic performance was assessed using sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy. Results: Among 241 lesions analyzed, 84 and 157 were histologically diagnosed as SDETs and NNLs, respectively. The diagnostic algorithm demonstrated excellent performance, with a sensitivity of 97.6% (95% confidence interval [CI]: 91.7–99.7%), specificity of 95.5% (95% CI: 91.0–98.2%), PPV of 92.1% (95% CI: 85.0–96.0%), NPV of 98.7% (95% CI: 95.0–99.7%), and overall accuracy of 96.3% (95% CI: 93.0–98.3%). Conclusion: This prospective validation showed that IEE-ME, applied through a structured algorithm, enables highly accurate and noninvasive differentiation between SDETs and NNLs. Given its excellent NPV and accuracy, this approach may serve as an optical biopsy method that reduces the need for conventional biopsies in clinical practice.This prospective observational study evaluated the diagnostic performance and clinical applicability of magnified endoscopic examination with image-enhanced endoscopy (IEE-ME) as an optical biopsy for differentiating superficial duodenal epithelial tumors (SDETs) from non-neoplastic lesions (NNLs) in the duodenum. Accurate discrimination of these lesions is essential for appropriate management; however, endoscopic diagnosis remains challenging. Duodenal biopsy carries potential risks such as bleeding and perforation. Therefore, a reliable and noninvasive diagnostic strategy is highly desirable. In this study, patients with some duodenal lesions were prospectively enrolled, and a previously proposed IEE-ME-based diagnostic algorithm was validated under real-world clinical conditions. Endoscopic diagnoses were performed in real time during routine examinations by endoscopists with varying levels of experience, enhancing the generalizability of the findings. Histopathological assessment, conducted in a blinded manner, served as the reference standard for diagnosis. The IEE-ME-based algorithm demonstrated excellent diagnostic performance, achieving a sensitivity of 97.6%, specificity of 95.5%, positive predictive value of 92.1%, negative predictive value of 98.7%, and accuracy of 96.3%. These results indicate that IEE-ME enables highly accurate differentiation between SDETs and NNLs without the need for routine biopsy. By employing a prospective design, incorporating real-time endoscopic evaluation, and including endoscopists with diverse experience levels, this study provides robust evidence supporting the clinical utility of IEE-ME. Our findings suggest that IEE-ME represents a practical and effective optical biopsy technique, with the potential to reduce unnecessary biopsies, minimize procedure-related risks, and optimize the management of superficial duodenal lesions in daily endoscopic practice.

Background and Aim: Remimazolam is a benzodiazepine receptor agonist intravenous anesthetic. This study aimed to evaluate the efficacy and safety of remimazolam for sedation during gastrointestinal endoscopy using real-world clinical data. Methods: This retrospective observational study included 352 patients who underwent esophagogastroduodenoscopy or colonoscopy sedated with remimazolam between January and February 2024 at our institution. Outcomes included the incidence of awakening during procedures, the sedation completion rate, and the incidence and severity of adverse events. Multivariate logistic regression analyses identified factors associated with hypoxia and hypotension. Results: Median patient age was 67 years (IQR: 58–74), and 62.2% were male. Median initial and additional doses were 3 (IQR: 2–3 mg) and 1 mg (IQR: 0–2 mg). Awakening occurred in 19.0% of patients. The sedation completion rate was 100%. Adverse events included hypotension (7.8%), hypoxia (13.1%), and bradycardia (4.0%), and no serious adverse events were observed. The only risk factor for hypoxia was advanced age (Odds ratio 1.04, 95% confidence interval: 1.01–1.08, p = 0.03), and the dose of remimazolam itself was not an independent risk factor for either hypoxia or hypotension. Conclusions: Remimazolam usage for gastrointestinal endoscopic sedation showed a favorable safety profile. Advanced age was associated with an increased risk of hypoxia, suggesting that careful monitoring and individualized sedation protocols are especially necessary for elderly patients. On the other hand, there are still issues regarding the duration of sedation. During long procedures, it is necessary to frequently check the depth of sedation to avoid undersedation.

Background: Bleeding and hematoma formation during submucosal injection in esophageal endoscopic submucosal dissection (ESD) reduce the visibility of the submucosa. Red dichromatic imaging (RDI) is an endoscopic technique that provides better visualization of the deep submucosal blood vessels. We speculated that blood vessel injury could be avoided with RDI. This pilot study evaluated the role of RDI in preventing bleeding and hematoma formation during esophageal ESD. Methods: This was a single-center retrospective observational study. We examined 60 patients who underwent ESD with white light imaging (WLI) and RDI. A single endoscopist reviewed all of the surgical videos to document the incidence and severity of bleeding episodes. Eighteen videos provided adequate quality and detail, and the number of blood vessels traversing the mucosal incision lines of the lesions in these videos was evaluated under WLI and RDI. Results: The WLI group had a significantly higher incidence of hematomas per unit area compared to the RDI group (0.18/cm2 [range 0–0.38] vs. 0 [0–0.18]/cm2, p = 0.024). The WLI group also had a significantly higher incidence of total bleeding episodes compared to the RDI group (42.9% [range 21.7–60.4] vs 16.7% [range 13.8–22.9], p < 0.001). Significantly more blood vessels were visible under RDI compared to WLI (5 [range 4–8] vs. 2 [range 1–5], p = 0.0020). Conclusion: RDI reduced the incidence of bleeding and hematoma formation during submucosal injection in esophageal ESD. It was assumed that the improvement of blood vessel visibility by RDI might have contributed to the result.

INTRODUCTION:Underwater endoscopic mucosal resection (UEMR) and cold snare polypectomy (CSP) are novel endoscopic procedures for superficial nonampullary duodenal epithelial tumors (SNADET). However, consensus on how to use both procedures appropriately has not been established. In this study, we evaluated treatment outcomes of both procedures, including resectability.METHODS:In this single-center randomized controlled study conducted between January 2020 and June 2022, patients with SNADET ≤12 mm were randomly allocated to UEMR and CSP groups. The primary end point was sufficient vertical R0 resection (SVR0), which was defined as R0 resection including a sufficient submucosal layer. We compared treatment outcomes including SVR0 rate between groups.RESULTS:The SVR0 rate was significantly higher in the UEMR group than in the CSP group (65.6% vs 41.5%, P = 0.01). By contrast, the R0 resection rate was not significantly different between study groups (70.3% vs 61.5%, P = 0.29). The submucosal layer thickness was significantly greater in the UEMR group than in the CSP group (median 546 [range, 309-833] m vs 69 [0-295] m, P < 0.01). CSP had a shorter total procedure time (median 12 [range, 8-16] min vs 1 [1-3] min, P < 0.01) and fewer total bleeding events (9.4% vs 1.5%, P = 0.06).DISCUSSION:UEMR has superior vertical resectability compared with CSP, but CSP has a shorter procedure time and fewer bleeding events. Although CSP is preferable for most small SNADET, UEMR should be selected for lesions that cannot be definitively diagnosed as mucosal low-grade neoplasias.

Background and Aims: Duodenal endoscopic submucosal dissection (ESD) is considered technically challenging and has a high risk of adverse events. However, we recently made some progress with the ESD technique and device by introducing 2 features: a water pressure (WP) method and a second-generation ESD knife (DualKnife) with a water jet function (DualKnife J). The present study aimed to assess whether these changes improved the clinical outcomes of duodenal ESD. Methods: This was a retrospective observational study. Among all patients who underwent ESD for superficial duodenal epithelial tumors from June 2010 to December 2018, patients in whom a single expert performed the procedure were included in this study. Various factors, including the use of the WP method and ESD devices (DualKnife or DualKnife J) and the treatment phase (early, mid, and late), were analyzed to determine whether they were associated with intraprocedural perforation and procedure time. Treatment phase was assigned by dividing the study population equally into 3 subgroups according to the treatment phase. Results: The procedure time was significantly shorter, and the proportion of patients with intraprocedural perforations was the lowest in the late phase. Multivariate analysis of the use of the WP method revealed that it significantly decreased the intraprocedural perforation rate (odds ratio, 0.39; 95% confidence interval, 0.16-0.96), and analysis of the use of both the WP method (β coefficient, −0.40; P <.01) and the DualKnife J (β coefficient, −0.10; P =.032) revealed they were independently and negatively correlated with procedure time. Conclusion: The present study reveals that the WP method significantly reduced the intraprocedural perforation rate and that both the WP method and the DualKnife J significantly shortened procedure times for duodenal ESD.

Endoscopic submucosal dissection (ESD) is an established technique for treating superficial gastric neoplasms. However, performing ESD in the cardia and pylorus remains technically challenging due to the narrow lumens and steep angulations. Recently, a novel therapeutic thin endoscope, featuring a 7.9-mm outer diameter, 160° downward angulation, 3.2-mm working channel, and water jet function, was developed. We aimed to evaluate the feasibility of this novel endoscope for ESD in the cardia and pylorus. We retrospectively reviewed the data from gastric ESD cases in the cardia and pylorus using this novel endoscope at a single tertiary care center between March 2023 and September 2024. Clinical characteristics, procedural details, and treatment outcomes were analyzed. A total of 20 lesions (10 in the cardia, 10 in the pylorus) were included. The median lesion size was 15 mm (interquartile range: 10–30 mm). En bloc resection was successfully achieved in all cases without any adverse events. None of the cases required traction devices. Retroflexion was unnecessary in approximately half of the cases. In conclusion, this novel therapeutic thin endoscope facilitated en bloc resection without any adverse events in all cases; suggesting its feasibility for gastric ESD in anatomically complex regions characterized by narrow lumens and steep angulations.

Background and Study Aim: Underwater endoscopic submucosal dissection (U-ESD) has recently been introduced as a technique that may improve visualization and submucosal layer expansion. However, the clinical outcomes of U-ESD for duodenal tumors have not been systematically evaluated. This study aimed to assess the efficacy and safety of U-ESD for duodenal tumors through a systematic review and meta-analysis. Patients and Methods: A comprehensive literature search was conducted using PubMed, Scopus, and the Cochrane Library from database inception to December 12, 2025. Studies evaluating U-ESD for duodenal tumors were included. Primary outcomes included en bloc resection, R0 resection, procedure time, adverse events, and complete mucosal defect closure. Pooled estimates were calculated using a random-effects model. Results: Four retrospective studies comprising 298 lesions treated with U-ESD were included. The pooled procedure time was 59 min (95% CI, 48–70 min; I2 = 72%). The pooled en bloc resection rate was 99% (95% CI, 97%–100%; I2 = 0%), and the pooled R0 resection rate was 89% (95% CI, 81%–93%; I2 = 54%). The pooled intraoperative perforation rate was 5% (95% CI, 1%–23%; I2 = 88%). The pooled delayed perforation and delayed bleeding rates were 1% (95% CI, 0%–3%; I2 = 0%) and 2% (95% CI, 1%–5%; I2 = 0%), respectively. Conclusion: Current evidence suggests that U-ESD is a feasible treatment option for duodenal tumors and is associated with favorable clinical outcomes. However, the available evidence remains limited, and potential biases and concerns regarding generalizability warrant cautious interpretation of these findings.

Duodenal endoscopic submucosal dissection (ESD) is a high-risk technique; however, prophylactic closure of mucosal defects reduces the risk. Unfortunately, we have encountered cases where closure is difficult, especially in large lesions. Therefore, we developed a novel closure technique, a string clip suturing method with an anchor (SCSM-A). This study aimed to elucidate the feasibility of this method. Five patients underwent this method for the closure of mucosal defects after duodenal ESD. The initial string clip was deployed at the anal end of the mucosal defects and the second clip was deployed at the other end of the mucosal defect. A third clip was deployed on the muscular layer in the middle of the mucosal defect. The free end of the string was pulled, and additional clips were deployed around the first to the third clips for complete closure. Because of grasping the muscle layer, SCSM-A can be employed for secure closure without creating a pocket. We reviewed the background and clinical course of hospitalization of patients who underwent this method. The resected specimens ranged from 52 to 103 mm in diameter. Complete closure of the mucosal defects was possible in all the cases. There were no adverse events, and no cases required additional treatment. All the patients were discharged within 7 days. The new method achieved secure closure even for large mucosal defects after duodenal ESD. This is a technique that can be applied to other organs, e.g., the colon.

Background and Aims: It has been reported that the prophylactic closure of mucosal defects after duodenal endoscopic resection (ER) can reduce delayed adverse events; however, under certain circumstances, this can be technically challenging. Therefore, the aim of this study was to determine the predictors of difficulty during the complete closure of mucosal defects after duodenal ER. Methods: This was a retrospective study of duodenal lesions that underwent ER between July 2010 and May 2020. We reviewed the endoscopic images and analyzed the relationships between the degree of closure or closure time and clinical features of the lesions using univariate and multivariate analyses. Results: We analyzed 698 lesions. The multivariate analysis revealed that lesion location in the medial or anterior wall (odds ratio, 2.8; 95% confidence interval, 1.36-5.85; P < .01) and a large lesion size (odds ratio, 1.4; 95% confidence interval, 1.07-1.89; P = .03) were independent predictors of an increased risk of incomplete closure. Moreover, a large lesion size (β coefficient, .304; P < .01), an occupied circumference over 50% (β coefficient, .178; P < .01), intraoperative perforation (β coefficient, .175; P < .01), treatment period (β coefficient, .143; P < .01), and treatment with endoscopic submucosal dissection (β coefficient, .125; P < .01) were independently and positively correlated with a prolonged closure time in the multiple regression analysis. Conclusions: This study revealed that lesion location in the medial or anterior wall and lesion size affected the incomplete closure of mucosal defects after duodenal ER, and lesion size, occupied circumference, intraoperative perforation, treatment period, and treatment method affected closure time.