Liver decompensation as late complication in HCC patients with long-term response following selective internal radiation therapy

Simple Summary: Hepatocellular carcinoma (HCC) is one of the deadliest forms of cancer. Selective internal radiation therapy (SIRT) is one of the therapeutic options for treatment of advanced HCC. Studies show that SIRT has a high objective response rate, but lack of survival benefit when compared to different treatment modalities. We hypothesized that this is due to potential damage in healthy liver parenchyma as a side-effect of SIRT, resulting in functional changes to the liver. This can ultimately result in liver decompensation and potentially death. The aim of this retrospective study was to assess long-term liver-related complications after SIRT in patients with HCC. We analyzed patients who underwent SIRT and found that liver decompensation occurred more often after SIRT when compared to sorafenib. However, careful patient selection may result in a survival benefit after SIRT when compared to other treatments. The ABLI score may be a valuable prognostic score for selecting patients.Selective internal radiation therapy (SIRT) is used as a treatment for hepatocellular carcinoma (HCC). The aim of this study was to assess long-term liver-related complications of SIRT in patients who had not developed radioembolization-induced liver disease (REILD). The primary outcome was the percentage of patients without REILD that developed Child-Pugh (CP) & GE; B7 liver decompensation after SIRT. The secondary outcomes were overall survival (OS) and tumor response. These data were compared with a matched cohort of patients treated with sorafenib. Eighty-five patients were included, of whom 16 developed REILD. Of the remaining 69 patients, 38 developed liver decompensation CP & GE; B7. The median OS was 18 months. In patients without REILD, the median OS in patients with CP & GE; B7 was significantly shorter compared to those without CP & GE; B7; 16 vs. 31 months. In the case-matched analysis, the median OS was significantly longer in SIRT-treated patients; 16 vs. 8 months in sorafenib. Liver decompensation CP & GE; B7 occurred significantly more in SIRT when compared to sorafenib; 62% vs. 27%. The ALBI score was an independent predictor of liver decompensation (OR 0.07) and OS (HR 2.83). After SIRT, liver decompensation CP & GE; B7 often developed as a late complication in HCC patients and was associated with a shorter OS. The ALBI score was predictive of CP & GE; B7 liver decompensation and the OS, and this may be a valuable marker for patient selection for SIRT.Imaging- and therapeutic targets in neoplastic and musculoskeletal inflammatory diseas

Eligibility for Liver Transplantation in Patients with Perihilar Cholangiocarcinoma

Background: Liver transplantation (LT) has been performed in a select group of patients presenting with unresectable or primary sclerosing cholangitis (PSC)-associated perihilar cholangiocarcinoma (pCCA) in the Mayo Clinic with a reported 5-year overall survival (OS) of 53% on intention-to-treat analysis. The objective of this study was to estimate eligibility for LT in a cohort of pCCA patients in two tertiary referral centers. Methods: Patients diagnosed with pCCA between 2002 and 2014 were included from two tertiary referral centers in the Netherlands. The selection criteria used by the Mayo Clinic were retrospectively applied to determine the proportion of patients that would have been eligible for LT. Results: A total of 732 consecutive patients with pCCA were identified, of whom 24 (4%) had PSC-associated pCCA. Overall, 154 patients had resectable disease on imaging and 335 patients were ineligible for LT because of lymph node or distant metastases. An age limit of 70 years led to the exclusion of 50 patients who would otherwise be eligible for LT. After applying the Mayo Clinic criteria, only 34 patients (5%) were potentially eligible for LT. Median survival from diagnosis for these 34 patients was 13 months (95% CI 3–23). Conclusion: Only 5% of all patients presenting with pCCA were potentially eligible for LT under the Mayo criteria. Without transplantation, a median OS of about 1 year was observed

De zeewaartse randvoorwaarde bij de 1-D modellering van zoutvorming in goed gemengde estuaria

Door de binnendringing van zeewater is het water in estuaria voor een deel zout. Het zoutgehalte varieert dagelijks onder invloed van het getij. Variaties in het zoutgehalte op de langere termijn kunnen onstaan door wisselende omstandigheden, zoals bijvoorbeeld een veranderende bovenafvoer. Het zoutgehalte beïnvloedt de chemische en biologische eigenschappen van water en is als zodanig verantwoordelijk voor een aantal specifieke kenmerken van estuaria. Ook de geschiktheid van het water voor menselijk gebruik wordt in belangrijke mate bepaald door het zoutgehalte. In het kader van waterkwaliteitsstudies worden daarom wiskundige modellen gebruikt om het zoutgehalte te kunnen voorspellen. Bij goed gemengde rivieren kan de zoutverdeling in de langsrichting van de rivier vaak voldoende nauwkeurig beschreven worden met door één dimensionaal (1-D) dispersiemodel. Het gebruik hiervan is door de eenvoudige opzet aantrekkelijk. Voor sterk geschematiseerde gevallen kan de dispersievergelijking, door toepassing van de quasi stationaire benaderingsmethode, analytisch opgelost worden. In de overige gevallen kan de oplossing met behulp van een eenvoudig numeriek model verkregen worden.VloeistofmechanicaHydraulic EngineeringCivil Engineering and Geoscience

Finite element modelling of transport and non-hydrostatic flow in environmental fluid mechanics

Sectie VloeistofmechanicaCivil Engineering and Geoscience

Flow structure caused by a local cross-sectional area increase and curvature in a sharp river bend

<p>Horizontal flow recirculation is often observed in sharp river bends, causing a complex three-dimensional flow structure with large implications for the morphological and planimetric development of meanders. Several field observations in small-scale systems show that sharp bends are often found in association with a strong increase in cross-sectional area, the deposition of outer bank benches, and reattachment bars near the inner bank. Recent studies show that these bends can also occur in large-scale systems. In this study, we present field measurements of a sharp bend in the Mahakam River, East Kalimantan, Indonesia. The cross-sectional area increases by a factor of 3 compared with the reach-averaged cross-sectional area. Along a river reach of about 150 km, cross-sectional area correlates strongly with curvature. The field measurements are analyzed together with the results from numerical simulation with a three-dimensional finite element model, which yields a comprehensive view of the intricate flow structure. In turn, the model is used to validate a new equation that captures the water surface topography dependence on cross-sectional area variation and curvature. The results show the importance of the increase in cross-sectional area in the development of horizontal recirculation. Vertical acceleration of the flow into the scour causes the pressure to deviate from a hydrostatic pressure distribution. Strong downflow (up to 12 cm s^-1) advects longitudinal momentum toward the bed, causing the flow to concentrate in the lower part of the cross section. This increases the velocity magnitude throughout the cross section, which is expected to maintain the large scour depth found in several bends along the Mahakam River.</p

Open Channel Flow

Civil Engineering and GeosciencesHydraulic Engineerin

Energy Stable and Momentum Conserving Hybrid Finite Element Method for the Incompressible Navier–Stokes Equations

A hybrid method for the incompressible Navier–Stokes equations is presented. The ethod inherits the attractive stabilizing mechanism of upwinded discontinuous Galerkin methods hen momentum advection becomes significant, equal-order interpolations can be used for the velocity nd pressure fields, and mass can be conserved locally. Using continuous Lagrange multiplier paces to enforce flux continuity across cell facets, the number of global degrees of freedom is the same s for a continuous Galerkin method on the same mesh. Different from our earlier investigations on he approach for the Navier–Stokes equations, the pressure field in this work is discontinuous across ell boundaries. It is hown that this leads to very good local mass conservation and, for an appropriate hoice of finite element spaces, momentum conservation. Also, a new form of the momentum ransport terms for the method is constructed such that global energy stability is guaranteed, even n the absence of a pointwise solenoidal velocity field. Mass conservation, momentum conservation, nd global energy stability are proved for the time-continuous case and for a fully discrete scheme. he presented analysis results are supported by a range of numerical simulations.Hydraulic EngineeringCivil Engineering and Geoscience

The performance of a weir-mounted tidal turbine: An experimental investigation

The tidal flow between bridge pillars and through open barriers is a promising source of ocean energy which can be exploited using tidal stream turbines, as proven recently by operational demonstration plants. The aim of this study is to clarify the consequences for the power output of tidal turbines when placing them in a hydraulic structure. To this end, experimental measurements of turbine power and wakes are performed, using a down-scaled turbine mounted at a submerged weir. The results are compared to an analytical model, validating its range of application for optimising turbine-weir geometries. The experimental data show that the power coefficient of the turbine can be increased by optimising the blockage of the channel and the distance between the turbine and the structure, which is related to the wake configuration. In this way, the power coefficient increased by 40% when the turbine was re-positioned from the upstream to the downstream end of the structure. The theoretical model could reproduce the measured power within 10% accuracy, proving its value as a rapid assessment tool. As such, this work advances the knowledge needed to meet targets on the transition towards renewable energy.</p

Estimating the stability of a bed protection of a weir-mounted tidal turbine

Coastal infrastructure, such as bridges and storm surge barriers with weirs, provides an attractive location for harvesting renewable energy using tidal turbines. Often stone layers are applied downstream of coastal infrastructure to protect the sea bed from erosion. However, little is known about the potential effect of tidal energy extraction on the stability of this granular bed protection. This paper describes a study of the flow conditions influencing the stability of the bed protection downstream of a weir-mounted tidal turbine, using hydrodynamic data of an experimental test. The analysis indicates that the flow recirculation zone downstream of a weir may become shorter and flatter due to the presence of a horizontal-axis turbine. As a result, energetic turbulence eddies can transport more horizontal momentum towards the bed - hence the reason a heavier bed protection may be required for granular beds downstream of weirs when a turbine is installed. This information is essential when designing safe bed protections for coastal infrastructure with tidal turbines.</p

Breaching Flow Slides and the Associated Turbidity Current

This paper starts with surveying the state-of-the-art knowledge of breaching flow slides, with an emphasis on the relevant fluid mechanics. The governing physical processes of breaching flow slides are explained. The paper highlights the important roles of the associated turbidity current and the frequent surficial slides in increasing the erosion rate of sediment. It also identifies the weaknesses of the current breaching erosion models. Then, the three-equation model of Parker et al. is utilised to describe the coupled processes of breaching and turbidity currents. For comparison’s sake, the existing breaching erosion models are considered: Breusers, Mastbergen and Van Den Berg, and Van Rhee. The sand erosion rate and hydrodynamics of the current vary substantially between the erosion models. Crucially, these erosion models do not account for the surficial slides, nor have they been validated due to the scarcity of data on the associated turbidity current. This paper motivates further experimental studies, including detailed flow measurements, to develop an advanced erosion model. This will improve the fidelity of numerical simulations.Environmental Fluid Mechanic