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Objectives: The aim of the current study was to compare the efficacy of partially covered duodenal stent (PCDS) vs. uncovered duodenal stent (UCDS) in patients suffering from unresectable primary malignant gastric outlet obstruction (GOO). Methods: This was a prospective international randomized controlled study conducted in 10 high‐volume institutions. Consecutive patients suffering from malignant GOO were recruited. The primary outcome measurement was the reintervention rate. Secondary outcomes included technical and clinical success, 30‐day adverse events, 30‐day mortality, causes of stent dysfunction, and the duration of stent patency. Results: Between March 2017 and October 2020, 115 patients (59 PCDS, 56 UCDS) were recruited. The 1‐year reintervention was not significantly different (PCDS vs. UDCS = 12/59, 20.3% vs. 14/56, 25%, P = 0.84). There was a trend to fewer patients with tumor ingrowth in the PCDS group (6/59 [10.2%]) vs. 13/56 [23.2%], P = 0.07). There were no significant differences in the technical success (100% vs. 100%, P = 1), clinical success (91.5% vs. 98.2%, P = 0.21), procedural time (21.5 [interquartile range [IQR] 17–30] vs. 20.0 [IQR 15–34.75], P = 0.62), hospital stay (4 [IQR 3–12] vs. 5 [IQR 3–8] days, P = 0.81), 30‐day adverse events (18.6% vs. 14.3%, P = 0.62), or 30‐day mortality (6.8% vs. 5.2%, P = 1.00). Conclusion: The use of PCDS was associated with a lower risk of tumor ingrowth but did not improve on reintervention rates or stent patency. Both kinds of stents could be used in this group of patients. [ABSTRACT FROM AUTHOR]

Micro/nanorobotic swarms consisting of numerous tiny building blocks show great potential in biomedical applications because of their collective active delivery ability, enhanced imaging contrast, and environment-adaptive capability. However, in vivo real-time imaging and tracking of micro/nanorobotic swarms remain a challenge, considering the limited imaging size and spatial-temporal resolution of current imaging modalities. Here, we propose a strategy that enables real-time tracking and navigation of a microswarm in stagnant and flowing blood environments by using laser speckle contrast imaging (LSCI), featuring full-field imaging, high temporal-spatial resolution, and noninvasiveness. The change in dynamic convection induced by the microswarm can be quantitatively investigated by analyzing the perfusion unit (PU) distribution, offering an alternative approach to investigate the swarm behavior and its interaction with various blood environments. Both the microswarm and surrounding environment were monitored and imaged by LSCI in real time, and the images were further analyzed for simultaneous swarm tracking and navigation in the complex vascular system. Moreover, our strategy realized real-time tracking and delivery of a microswarm in vivo, showing promising potential for LSCI-guided active delivery of microswarm in the vascular system. Editor's summary: Micro- and nanorobots have been widely proposed for various medical applications, including drug delivery and thrombolysis. However, tracking these swarms of robots in real time has been challenging, especially for imaging modalities that rely on extended exposure to ionizing radiation. Wang et al. report on the use of laser speckle contrast imaging to track a swarm of magnetic nanorobots within blood vessels in real time and guide their endovascular navigation. The authors demonstrated the potential for high contrast imaging and navigation of the swarm of nanorobots in stagnant and flowing blood environments ex vivo and in vivo. The findings offer an opportunity for improvements in targeted endovascular delivery. —Amos Matsiko [ABSTRACT FROM AUTHOR]

Laparoscopic surgery (LS) has become an effective and widely accepted therapy for patients. However, performing LS requires advanced training and skills, as it demands high precision and dexterity due to visual feedback depending on the collaboration between the surgeon and endoscope assistant, restricted field of view, and limited dexterity inside the body. Thus, a flexible endoscope holder system with an automatic control scheme is proposed to assist LS performance, allowing the surgeon to perform solo LS. A DNA‐inspired helix‐based structure with wide‐angle and constant curvature bending is presented and made of printable nylon with selective laser sintering. The proposed flexible mechanism reduces the cost of manufacturing and assembling. Also, it has a hollow design for embedded sensing and actuation. Then, an optimization method is proposed, which provides a reference for the endoscope installation, robot placement, and pose selection. In addition, aiming at the misorientation problem, a pose‐constrained visual servoing control scheme for the endoscope system is developed. Both simulation and physical experiments are conducted to verify the effectiveness and feasibility of the proposed control scheme. Experimental results demonstrate that the proposed visual servoing scheme can maintain the optimized pose and reduce misorientation during automatic view steering. [ABSTRACT FROM AUTHOR]

Colorectal cancer stands as one of the most prevalent cancers globally, representing 9.8% of total cases and contributing to 9.2% of mortalities annually. Robotic "front-wheel" navigating colonoscopes mitigate aggressive stretching against the long and tortuous colonic wall, alleviating associated discomfort and pain typically experienced by patients inspected by conventional "back-wheel" navigating colonoscopes. The anchoring unit of most "front-wheel" navigating colonoscopes plays a crucial role in ensuring effective locomotion by preventing slipping during elongation/contraction of the central actuation part. The soft balloon anchoring actuator emerges as a promising solution due to its high compliance. This study introduces a dumbbell-shaped balloon anchoring actuator (DBAA) integrating an "inflation and suction" mechanism to address the inherent conflict between achieving sufficient anchoring force and minimizing expansion and potential trauma of the colonic wall, commonly encountered in current balloon anchoring actuators. Analytical modeling of DBAA and soft external lumen, encompassing geometric deformation and anchoring force, were proposed to characterize the actuator and provide guidelines for designing and controlling DBAA in further applications, enabling autonomous anchoring within different diameter lumens and achieving the expected anchoring force. A comprehensive set of validation experiments was conducted, and the outcomes revealed high consistency with analytical predictions, confirming the effectiveness of the proposed analytical modeling approach. Furthermore, the results demonstrated a significant enhancement in anchoring force with the proposed actuator and corresponding mechanism while concurrently maintaining low-lumen expansion. For instance, in a lumen sample with R   i n = 15 m m ,   Λ 2 = 105 % , the anchoring force reaches 14.5 N with 50 kPa negative pressure, which is 12.4 times of the force (1.17 N) observed without applying negative pressure.

Antithrombotic agents, including antiplatelet agents and anticoagulants, are widely used in Korea because of the increasing incidence of cardiocerebrovascular disease and the aging population. The management of patients using antithrombotic agents during endoscopic procedures is an important clinical challenge. The clinical practice guidelines for this issue, developed by the Korean Society of Gastrointestinal Endoscopy, were published in 2020. However, new evidence on the use of dual antiplatelet therapy and direct anticoagulant management has emerged, and revised guidelines have been issued in the United States and Europe. Accordingly, the previous guidelines were revised. Cardiologists were part of the group that developed the guideline, and the recommendations went through a consensus-reaching process among international experts. This guideline presents 14 recommendations made based on the Grading of Recommendations, Assessment, Development, and Evaluation methodology and was reviewed by multidisciplinary experts. These guidelines provide useful information that can assist endoscopists in the management of patients receiving antithrombotic agents who require diagnostic and elective therapeutic endoscopy. It will be revised as necessary to cover changes in technology, evidence, or other aspects of clinical practice.

Antithrombotic agents, including antiplatelet agent and anticoagulants are widely used in Korea due to increasing incidence of cardio-cerebrovascular disease and aging population. The management of patients using antithrombotic agents during endoscopic procedures is an important clinical challenge. Clinical practice guideline regarding this issue which was developed by the Korean Society of Gastrointestinal Endoscopy was published in 2020. However, since then, new evidence has emerged for the use of dual antiplatelet therapy and direct anticoagulant management, and revised guidelines were issued in the US and Europe. Accordingly, the previous guidelines were revised, cardiologists also participated in the development group, and the recommendations went through a consensus process among international experts. This guideline presents 14 recommendations made according to the Grading of Recommendations, Assessment, Development, and Evaluation methodology, and was reviewed by multidisciplinary experts. This guideline provides useful information that can assist endoscopists in the management of patients on antithrombotic agents who require diagnostic and elective therapeutic endoscopy. It will be revised as necessary to cover changes in technology, evidence, or other aspects of clinical practice.