Background
The Japanese Society of Hepato‐Biliary‐Pancreatic Surgery launched the clinical practice guidelines for the management of biliary tract cancers (cholangiocarcinoma, gallbladder cancer, and ...ampullary cancer) in 2007, then published the 2nd version in 2014.
Methods
In this 3rd version, clinical questions (CQs) were proposed on six topics. The recommendation, grade for recommendation, and statement for each CQ were discussed and finalized by an evidence‐based approach. Recommendations were graded as Grade 1 (strong) or Grade 2 (weak) according to the concepts of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system.
Results
The 31 CQs covered the six topics: (a) prophylactic treatment, (b) diagnosis, (c) biliary drainage, (d) surgical treatment, (e) chemotherapy, and (f) radiation therapy. In the 31 CQs, 14 recommendations were rated strong and 14 recommendations weak. The remaining three CQs had no recommendation. Each CQ includes a statement of how the recommendations were graded.
Conclusions
This latest guideline provides recommendations for important clinical aspects based on evidence. Future collaboration with the cancer registry will be key for assessing the guidelines and establishing new evidence.
Highlight
These guidelines are the English version of “Evidence‐based clinical practice guidelines for the management of biliary tract cancers, 3rd edition” published in Japanese by the Japanese Society of Hepato‐Biliary‐Pancreatic Surgery in 2019. A total of 31 clinical questions covering six topics provide recommendations for important clinical aspects based on evidence.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
•High spatial and temporal resolution of hypersonic flow-field measurements•Visualization of hypersonic phenomena such as shock interactions and expansion waves
Anodized aluminum pressure sensitive ...(AAPSP) and temperature sensitive paints (AATSP) were applied to a 30° compression corner model in the Mach 7.1 Hypersonic and High Enthalpy Wind Tunnel at the University of Tokyo, Kashiwa Campus. The measurement technique was able to capture spatially resolved unsteady hypersonic flow phenomena over the surface of the model at a rate of 10 Hz for pressure measurements and 30Hz for temperature measurements. High heating due to oblique shocks and flow stagnation was observed at the leading edge of the model. Shock-shock interactions, confirmed by schlieren imagery were clearly visible in the pressure distribution. Görtler vortices consistent with boundary layer growth over a concave wall were also visible in both the pressure and temperature maps produced by the AAPSP and AATSP. The tests demonstrate the effective use of AAPSP and TSP for spatially resolved measurements in hypersonic flow. The temporal resolution of the measurement was limited by camera technology, and can be improved without modifications to the luminescent sensors.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study examines the wing hinge oscillations in an aircraft concept that employs multiple wings, or small aircraft, chained at the wing tips through freely rotatable hinges with minimal structural ...damping and no mechanical position-locking system. This creates a single pseudo long-span aircraft that resembles a flying chain oriented perpendicular to the flight direction. Numerical calculations were conducted using the vortex lattice method and modified equations for a multi-link rigid body pendulum. The calculations demonstrated good agreement with small-scale wind tunnel experiments, where the motion of the chained wings was tracked through color tracking, and the forces were measured using six-axis force sensors. The total CL/CD increased for the chained wings, even in the presence of hinge joint oscillations. Furthermore, numerical simulations assuming an unmanned airplane size corroborated the theoretical attainment of passive stability with high chained numbers (≥9 wings), without any structural damping and relying solely on aerodynamic forces. Guidelines for appropriate hinge axis angle δ and angle-of-attack regions for different chained wing numbers to maximize passive oscillation stability were obtained. The results showed that wing-tip-chained airplanes could successfully provide substantially large wing spans while retaining flexibility, light weight and CL/CD, without requiring active hinge rotation control.
This paper describes the world's first successful simulation for lateral cutoff phenomena of sonic boom far from the flight path due to variation in atmospheric temperature with altitude. A flow ...field around an axi-symmetric paraboloid has been analyzed by the full-field simulation method that solves the three-dimensional Euler equations with a gravity term to create a horizontally stratified atmosphere. A solution-adapted structured grid is constructed to align the grid lines with the front and rear shock-wave surfaces in the entire domain, including the near field around a supersonic body and far field reaching the ground beyond lateral cutoff. The flight is assumed to have a speed of Mach 1.2 at an altitude of 10 km, and the computational domain ranges over a distance of 30 km from the axis of symmetry. The computational results show that the evanescent wave in the shadow zone beyond lateral cutoff decays exponentially and changes into a progressive rounding waveform. The characteristics of the waveform transition are in good agreement with those observed in the flight tests. Therefore, the full-field simulation is recognized as a promising approach for investigating sonic boom strength in the full extent of sonic boom noise, including lateral cutoff and evanescent waves. Moreover, the computational results clarify that sonic boom focusing occurs above the ground, except for the vicinity of the ground, and the focusing strength along the lateral cutoff curve detected from the three-dimensional shock-wave surface increases with altitude. The results of ray tracing analysis collaborate the reasonability of the simulation results, and the caustic of downward convex agrees well with the lateral cutoff curve. In the shadow zone, the magnitude of exponential decay increases with altitude, and the lateral distance where the pressure rise decreases rapidly shortens with altitude.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Background
Adding segment 4 (S4) portal vein embolization (PVE) to right PVE before right hepatic trisectionectomy is controversial. We retrospectively examined the effect of S4 PVE on segments 2 and ...3 (S2 + 3) hypertrophy.
Methods
We reviewed patients with biliary carcinoma who underwent right PVE with (R3PVE) or without (R2PVE) S4 PVE using gelatin sponge particles and coils (2010‐2019). Propensity score matching balanced the cohort for baseline characteristics, including total liver volume and S2 + 3 volume before PVE. We compared the groups regarding the S2 + 3 volume changes after PVE.
Results
Of 178 enrolled patients, 38 underwent R3PVE for right hepatic trisectionectomy and 140 underwent R2PVE for right hepatectomy. Twenty‐eight patients from each group were respectively matched. The median absolute volume increase in (146 cm3 vs 70 cm3), hypertrophy rate of (52.4% vs 32.3%), and kinetic growth rate of (3.1%/wk vs 2.0%/wk) S2 + 3 were significantly higher in the R3PVE group than in the R2PVE group. In the pre‐matched cohort, the rate of posthepatectomy liver failure and postoperative hospital stay did not significantly differ between the patients who underwent right hepatic trisectionectomy and right hepatectomy.
Conclusion
R3PVE increased the S2 + 3 volume more effectively than R2PVE in patients with biliary carcinoma.
Highlight
Comparing patients who underwent right trisegment portal vein embolization and right portal vein embolization, Ito and colleagues demonstrated that segment 4 portal vein embolization added to right portal vein embolization before right hepatic trisectionectomy significantly improved segment 2 and 3 hypertrophy. Propensity score matching balanced the cohort for baseline characteristics.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Although most fatalities in tsunami-related disasters are conjectured to be a result of drowning, injury risk owing to collision with other floating debris or fixed buildings has not been studied ...sufficiently. In this study, the impact force corresponding to the collision of a concrete block and drifting test body in a tsunami wave was experimentally investigated, and the injury risk was evaluated in terms of different biomechanical indexes; specifically, maximum acceleration, head injury criterion, and impact force. The injury risk indicated by the considered indexes was reasonably low. It was noted that if a healthy adult collided with a concrete wall under a velocity of 2.5 m s-1 and wave height of 0.59 m, the adult would likely not be critically injured. However, a similar collision impact poses considerable risk to infants and children, as well as the more sensitive regions of the adult body. Moreover, in the case of large tsunamis, such as that in the 2011 Great East Japan Earthquake, a drifting person may be at considerable risk for injuries. The collision impact occurring on the tip of a surge flow is notably significantly larger than that on a bore flow. This is because a surge flow, which arrives at the concrete block earlier than a bore flow, forms a certain water layer along the concrete wall and that layer acts as a cushion for any body drifting on the bore flow, indicating the importance of such a buffering effect. These findings can provide practical guidance regarding the formulation of effective tsunami-protection measures.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Objectives
To evaluate the utility of multiphase contrast-enhanced computed tomography (CT) findings alone and in combination for differentiating focal-type autoimmune pancreatitis (f-AIP) from ...pancreatic carcinoma (PC).
Methods
The study group comprised 22 f-AIP lesions and 61 PC lesions. Two radiologists independently evaluated CT findings. Frequencies of findings were compared between f-AIP and PC. Statistical, univariate and multivariate analyses were performed.
Results
Homogeneous enhancement during the portal phase (AIP, 59 % vs. PC, 3 %;
P
< 0.001), dotted enhancement during the pancreatic phase (50 % vs. 7 %;
P
< 0.001), duct-penetrating sign (46 % vs. 2 %;
P
< 0.001), enhanced duct sign (36 % vs. 2 %;
P
< 0.001) and capsule-like rim (46 % vs. 3 %;
P
< 0.001) were more frequently observed in AIP. Ring-like enhancement during the delayed phase (5 % vs. 46 %;
P
< 0.001) and peripancreatic strands with a length of at least 10 mm (5 % vs. 39 %;
P
= 0.001) were more frequently observed in PC. AIP was identified with 82 % sensitivity and 98 % specificity using four of these seven findings. Multivariate analysis revealed significant differences in dotted enhancement (
P
= 0.004), duct-penetrating sign (
P
< 0.001) and capsule-like rim (
P
= 0.007).
Conclusions
The combination of CT findings may allow improvements in differentiating f-AIP from PC.
Key Points
•
f
-
AIP can mimic PC on imaging findings
.
•
The differentiation of f
-
AIP from PC is important in patient management
.
•
Some CT findings can be used to identify AIP
.
•
The combination of CT findings will improve differentiation from PC
.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, VSZLJ, ZAGLJ
Purpose: Heavily T2-weighted, 3-dimensional, fluid-attenuated inversion recovery (hT2W-3D-FLAIR) imaging has been reported to detect low concentrations of gadolinium-based contrast media (GBCM) in ...the anterior eye segment (AES), subarachnoid space (SAS), and labyrinthine perilymph as well as in the cerebrospinal fluid (CSF) of the internal auditory canal (IAC) 4 hours after intravenous administration of a single dose (IV-SD-GBCM) in patients with inner ear disorders. To elucidate the time course of contrast enhancement in healthy volunteers, we obtained hT2W-3D-FLAIR serially after IV-SD-GBCM. Materials and Methods: We obtained hT2W-3D-FLAIR before and 0.5, 1.5, 3, 4.5 and 6 hours after IV-SD-GBCM in 6 healthy volunteers and measured signal intensity of the AES, SAS surrounding the optic nerve (SAS-ON), SAS in Meckel's cave (SAS-MC), pontine parenchyma, CSF in the IAC (CSF-IAC), CSF in the ambient cistern (CSF-AC), CSF in the lateral ventricles (CSF-LV), perilymph (PL), and endolymph (EL) in the labyrinth. We then compared averaged values among all time points using analysis of variance (ANOVA). Results: After IV-SD-GBCM, we observed no change in signal intensity in the pontine parenchyma, CSF-LV, or EL and significant enhancement in all other structures. Maximum enhancement was most frequent at 4.5 hours after IV-SD-GBCM in the SAS-ON and PL, at 1.5 hours in the AES and SAS-MC, and at 3 hours in the CSF-IAC and CSF-AC. Conclusions: Contrast enhancement can be detected by hT2W-3D-FLAIR in the AES, SAS-ON, SAS-MC, PL, CSF-IAC, and CSF-AC in healthy volunteers after IV-SD-GBCM. Timing of maximum enhancement differed among locations. These data might serve as basic knowledge for future clinical research.
Purpose
We developed a thermoset shape memory bolus (shape memory bolus) made from poly‐ε‐caprolactone (PCL) polymer. This study aimed to investigate whether the shape memory bolus can be applied to ...radiotherapy as a bolus that conformally adheres to the body surface, can be created in a short time, and can be reused.
Methods
The shape memory bolus was developed by cross‐linking tetrabranch PCL with reactive acrylate end groups. Dice similarity coefficient (DSC) was used to evaluate shape memory characterization before deformation and after restoration. In addition, the degree of adhesion to the body surface and crystallization time were calculated. Moreover, dosimetric characterization was evaluated using the water equivalent phantom and an Alderson RANDO phantom.
Results
The DSC value between before deformation and after restoration was close to 1. The degree of adhesion of the shape memory bolus (1.9%) was improved compared with the conventional bolus (45.6%) and was equivalent to three‐dimensional (3D) printer boluses (1.3%–3.5%). The crystallization time was approximately 1.5 min, which was clinically acceptable. The dose calculation accuracy, dose distribution, and dose index were the equivalent compared with 3D boluses.
Conclusion
The shape memory bolus has excellent adhesion to the body surface, can be created in a short time, and can be reused. In addition, the shape memory bolus needs can be made from low‐cost materials and no quality control systems are required for individual clinical departments, and it is useful as a bolus for radiotherapy.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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