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Thermal barrier coatings (TBC) are multi-layer system deposited on gas turbines components to protect their metallic surface from hot combustion gases. Depending on the operating conditions of the gas turbine, solid particle erosion can became critical for TBCs lifetime: in fact, sand, volcanic ashes could enter into the turbine promoting erosion. At RSE solid particle erosion tests have been performed in different testing conditions (particle speed, erodent composition, impingement angle and temperature) on TBC with different microstructures for comparison purposes. As A first step to forecast erosion in gas turbine, the laboratory jet tester has been simulated by a simple analytical model describing the speed of erodent particles as a function of their size and shape. By this way, for each TBC type, the volume eroded by a single particle is estimated and a rough evaluation of the overall erosion rate has been obtained, after a preliminary calibration of a kinetic energy model performed by using experimental data. Simulated erosion rate for four different types of TBCs (standard porous APS, EB-PVD, PS-PVDTM and highly segmented APS) has been investigated as a function of the test conditions, and compared with experimental data. [ABSTRACT FROM AUTHOR]

Purpose: Personalized treatment schemes are being systematically applied to ensure best treatment outcome in oncologic patients. This is true also for personalized dosimetry in transarterial radioembolization (TARE) in hepatocellular carcinoma (HCC) patients. Precise and detailed volumetric and functional data derived from radiological and nuclear imaging methods are essential for personalized dosimetry. We sought to evaluate accuracy of dual-phase cone-beam CT (CBCT) in comparison to pre-treatment contrast-enhanced CT (CECT), and 99m Tc-macroaggregated albumin-SPECT/CT ([ 99m Tc]MAA SPECT/CT) to predict and assess the efficacy of TARE based on post-treatment 90 Y PET/CT., Material and Methods: Thirty consecutive patients with HCC treated with TARE were included. Intraprocedural dual-phase CBCT acquisition protocol was developed to distinguish tumor volume in the early arterial phase and perfused volume of non-affected liver in the late arterial phase. Volumetric data obtained from pre-treatment CECT, dual-phase CBCT and [ 99 m Tc]MAA SPECT/CT were compared to post-treatment 90 Y PET/CT considered the standard reference. Treatment simulations for final calculated dose from the different imaging derived volumes were then compared to post-treatment 90 Y PET/CT., Results: CBCT resulted as the most accurate method in predicting tumor- (R 2 0.88) and perfused volumes (R 2 0.82). Dosimetry prediction planning performed on derived volumes from the different methods did not show significant difference (p < 0.05), yet highest concordance with 90 Y PET/CT data was observed with dual-phase CBCT., Conclusion: Our study shows that dual-phase CBCT acquisition is a novel alternative method for correctly and safely administering more accurate and defined doses during TARE., Clinicaltrials: gov ID: NCT03981497., Competing Interests: Declarations. Conflict of interests: The authors have no relevant financial or non-financial interests to disclose. Ethical approval: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments (EC approval 64/INT/2021). Consent to participate: Informed consent was obtained from all individual participants included in the study as described by Institutional Ethic Committee approval (64/INT/2021). Consent to publish: Consent for publication was obtained for every individual person’s data included in the study., (© 2024. The Author(s).)

Purpose: To compare safety, technical and clinical outcomes of double vein embolization (DVE) via a trans-jugular approach with liver venous deprivation (LVD) via a trans-hepatic approach., Materials and Methods: A single-center retrospective analysis was conducted on patients undergoing simultaneous portal and hepatic veins embolization in view of a major hepatectomy (June 2019-November 2022). Hepatic vein embolization was performed either by transjugular plug (DVE) or by transhepatic plug followed by glue injection (LVD). Inclusion criteria were availability of pre-procedural CT scan, and availability of CT scans acquired 10 days and 25 days post-procedure. Comparative data included complication rate, fluoroscopy time, dose area product (DAP), Future Liver Remnant volume and function increase (FLR-V and FLR-F increase, respectively) and clinical outcomes., Results: Thirty-six patients (n = 14 DVE; n = 22 LVD) were included. No baseline significant differences were observed among the two groups. One grade-3 complication (2.8%) was observed in the LVD group; one case of technical failure (2.8%) was observed in the DVE group. Fluoroscopy time and DAP were similar between DVE and LVD (29 ± 17.7 vs. 25 ± 8.2 min, p = 0.97; 105.1 ± 63.5 vs. 143.4 ± 79.5 Gy·cm 2 , p = 0.15). No differences arose at either time-point in FLR-V increase (46.7 ± 23.1% vs. 48.2 ± 28.2%, 52.9 ± 30.9% vs. 53.2 ± 29%, respectively, p = 0.9). FLR-F increase also did not differ significantly (62.8 ± 55.2 vs. 67.4 ± 57.5, p = 0.9). No differences in drop-out rate from surgery were observed. (28.6% vs. 27.3%, p = 0.93). One case of grade-B post-hepatectomy liver failure (2.8%) was observed in the LVD group., Conclusion: LVD via transhepatic approach and DVE via transjugular approach seem equally safe and effective. Level of Evidence Level 3, Retrospective Cohort Study., (© 2023. Springer Science+Business Media, LLC, part of Springer Nature and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE).)

Background: Embolisation of the parenchymal tract is a key step after any other transhepatic or transplenic percutaneous portal vein catheterization since eventual venous bleeding is difficult to control and may require surgical management. Different techniques have been proposed to perform tract embolisation. The aim of this study is to compare the safety and efficacy of different techniques of haemostasis of the parenchymal tract., Materials and Methods: All the interventional procedures with percutaneous transhepatic or transplenic access to the portal vein (excluding ipsilateral portal vein embolisation) from January 2010 to July 2020, in two tertiary hospitals, were retrospectively analyzed. The following data were evaluated: access site, the technique of embolisation, technical success in terms of immediate thrombosis of the tract, safety and clinical efficacy in terms of the absence of hemorrhagic and thrombotic complications., Results: One-hundred-sixty-one patients underwent 220 percutaneous transhepatic or transplenic portal vein catheterization procedures. The main indications were pancreatic islet transplantation, portal anastomotic stenosis after liver transplantation, and portal vein thrombosis recanalization. As embolic materials gelfoam was used in 105 cases, metallic micro-coils in 54 cases, and cyanoacrylic glue in 44 cases; in 17 cases the parenchymal tract was not embolized. Technical success was 98% without significant difference among groups (p-value = 0.22). Eighteen post-procedural abdominal bleedings occurred, all grade 3 and were managed conservatively; difference among groups was not significant (p-value = 0.25). We detected 12 intrahepatic portal branch thromboses not related to the embolisation technique; only one case of non-target embolisation was documented after liver tract embolisation with glue, without clinical consequences., Conclusion: Embolisation of the parenchymal tract after percutaneous portal vein catheterization is technically safe and effective. No significant differences were found between coils, glue, and gelfoam in effectiveness and complications rate., Level of Evidence: Level 3, Cohort study., (© 2022. The Author(s).)

Future liver remnant (FLR) volume is an important indicator of the risk of posthepatectomy liver failure (PHLF) and limits the feasibility of major hepatectomies. A case series of 5 patients treated with a novel approach is presented. Laparoscopic liver partitioning was combined with subsequent liver venous deprivation (embolization of both the portal and the hepatic veins). Baseline average FLR was 28.8%. All procedures were successfully performed without major complications. Mean 1-, 2- and 4-week hypertrophy of the FLR were 35%, 40.3%, and 46.4%, respectively. Four patients underwent planned surgery after a mean interval of 28 days. Of these, 2 patients achieved sufficient FLR volume and function after 2 weeks and underwent surgery before the 4-week volumetric analysis. One patient did not undergo surgery because of intraoperative diagnosis of peritoneal metastases. No cases of PHLF were observed at 5-day follow-up., (Copyright © 2022 SIR. Published by Elsevier Inc. All rights reserved.)

The aim of the present study is to analyze the feasibility and the impact of a two-step approach in the treatment of giant hemangiomas (GH) i.e., exceeding 10 cm in maximum diameter, consisting of transarterial embolization (TAE) followed by laparoscopic liver resection (LLR). Ten patients with 11 GH were treated with TAE and subsequent LLR between 2017 and 2020 (Group A). A matched cohort of 10 patients with GH treated with upfront LLR between 2014 and 2017 was identified for comparison (Group B). Data were analyzed regarding intraoperative and postoperative outcomes, including successful completion of LLR, morbidity, and mortality. Successful microparticle embolization of the GH-feeding arteries was performed in all patients in group A. In three cases a liquid embolic agent (Squid-18) was also injected to obtain complete embolization. No complications were observed after TAE. Successful surgery was performed after a mean time interval of 2.2 days from TAE without any case of conversion to laparotomy. Statistically significant differences between group A and group B were found in intraoperative blood loss (250 ± 200 vs. 400 ± 300 mL, p = 0.039), operative time (245 ± 60 vs. 420 ± 60 min, p = 0.027), and length of stay (5 ± 1 vs. 8 ± 2 days, p = 0.046). Our data suggest that two-step TAE + LLR might be a safe and effective option for surgical treatment of GH >10 cm.

Transjugular intrahepatic portosystemic shunt (TIPS) is currently indicated as first therapeutic option in the main complications of portal hypertension, including bleeding gastroesophageal varices and refractory ascites. In case of bleeding gastroesophageal varices, an adjuvant embolisation within TIPS can be useful to prevent rebleeding. In the present technical note, the management in emergency of a patient with haemorrhagic shock due to bleeding gastroesophageal varices and occluded TIPS is reported. TIPS recanalisation with an adjunctive stent and high-pressure balloon angioplasty and gastroesophageal varices embolisation using detachable coils and a non-adhesive liquid embolic agent were performed during the same emergent procedure. After the procedure, clinical stabilisation of the patient was achieved, with blood transfusions suspension and Blakemore tube removal. At 6 months, regular TIPS patency at colour Doppler and no rebleeding episodes were recorded. To our knowledge, whilst coils are routinely used for varices embolisation, non-adhesive liquid embolic agents have been never mentioned. Liquid embolic agents seem to provide a stable plug strengthening the embolising action of the coils. Further studies involving a cohort of patients with long-term follow-up will be necessary to confirm whether this association can be more effective than coils alone in gastroesophageal varices embolisation.

Purpose: To report the safety and efficacy of the embolization of splenic artery aneurysms (SAAs) with coils plus ethylene vinyl alcohol copolymer (EVOH) agent., Materials and Methods: A single-center retrospective study was conducted from 2016 to 2019 to collect SAAs. Twelve asymptomatic patients (mean age, 59 years) with 15 SAAs (mean size, 23.6 mm; size range, 15-40 mm) were treated with embolization. Embolization was performed with EVOH (Squid 8/34) and fibered detachable coils. Transfemoral embolization was performed with a microcatheter to achieve a splenic artery occlusion embolizing the SAA and its efferent and afferent branches. Follow-up was based on color Doppler ultrasound at 24 hours and on computed tomography (CT) angiography at 1 (n = 12) and 6 months (n = 12) after embolization. Mean number of coils and Squid vials used for each patient, major/minor complications, technical success, 30-day clinical success, cases of revascularization/reintervention, and mortality were assessed. Technical success was defined as complete exclusion of the aneurysmal segment and cessation of blood flow into the sac. Clinical success at 1 month was based on the absence of clinical symptoms and the exclusion of aneurysm revascularization on CT angiography., Results: The mean number of coils and Squid vials was 5.75 (standard deviation [SD], 1.58; range, 3-9) and 1.41 (SD, 0.49; range, 1-2), respectively. Both technical and 30-day clinical success were 100%, with no cases of aneurysm revascularization (CT angiography performed in all patients at 1 month and 6 months and in 3 patients at 24 months). No major complications or fatal events were recorded. In terms of minor complications, 2 cases of mild pancreatitis (transient amylases increase) and 1 case of focal splenic ischemia without clinical sequelae were recorded., Conclusions: Embolization in SAAs using coils plus EVOH was safe and effective without SAA revascularization., (Published by Elsevier Inc.)

Background: Squid, as Onyx, is an ethylene-vinyl alcohol copolymer (EVOH)-based liquid embolic agent developed for neuroradiologic interventions with poor application in abdominal district. Our aim was to evaluate safety, complications, and efficacy of transcatheter embolization using the two available formulations Squid-18 and 12, in 30 patients affected by different abdominal diseases., Results: Transcatheter embolization with Squid, combined with other embolic agents, as poly vinyl alcohol (PVA) particles, coils and amplatzer plugs, or alone (type 2 endoleak), was performed in 30 patients, as follows: 10 portal vein embolizations (PVEs), 6 arteriovenous malformations (AVMs), 5 visceral artery aneurysms (VAAs), 4 type 2 endoleaks, 3 preoperative embolizations, 1 acute arterial bleeding, 1 female varicocele. Squid was always administered using dimethyl sulfoxide (DMSO) compatible microcatheters. Technical success, 30-day clinical success and complications were assessed. Technical success was 90%. 3 patients (2 AVMs, 1 VAA) required re-intervention successfully performed in all cases. Major complications, cases of microcatheter entrapment and DMSO-related poor pain control were not recorded. 30-day clinical success was 93.3%: in 2 patients submitted to PVE a sufficient future liver remnant (FLR) hypertrophy was not achieved., Conclusion: Squid was successfully used with low complication rate in many abdominal diseases showing a valid embolic action either combined with other embolic agents or alone in type 2 endoleak. The availability of different formulations (Squid-18 and Squid-12) variable for viscosity makes Squid preferable to Onyx as EVOH-based liquid embolic agent, even though comparable studies in different abdominal districts with a larger cohort of patients will be necessary.

Diabetes mellitus is associated with both microvascular and macrovascular complications, which can result in visceral aneurysms as for example splenic artery aneurysms: in their management, an endovascular treatment, less invasive than surgery, is generally preferred. Endovascular treatment of splenic artery aneurysms can be based either on covered stenting (CS) or transcatheter embolization (TE). CS generally allows aneurysm exclusion with vessel preservation, while TE usually determines target artery occlusion with potential risk of distal ischemia. We performed a review of the existing literature on endovascular treatment of visceral artery aneurysms (VAAs) and psudoaneurysms (VAPAs) in the current era., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The occurrence of dripping and jetting regimes in a microfluidic coflowing injector device has been related recently to the spatio-temporal stability properties of the developed velocity profile. Dripping corresponds to an absolutely unstable flow while jetting is observed when the Rayleigh-Plateau instability of the core-annular jet is convective. In this work we take into account the effect of the entry region on the dripping to jetting transition by carrying out a global stability analysis of the steady two-phase base flow. We show that, depending on the flow parameters, the entry region can affect significantly the transition between the two regimes.

In this paper, we present a dynamic microfluidic tensiometer able to perform measurements over more than four decades and which is suitable for high throughput experimentations. This tensiometer is able to withstand hard conditions such as high pressure, high temperature, high salinity, and crude oil. It is made of two coaxial capillaries in which two immiscible fluids are injected. Depending on the flow rate of each phase, either droplets or jetting will be obtained. The transition between these two regimes relies on the Rayleigh-Plateau instability. This transition can be theoretically computed thanks to a linear analysis based on the convective and absolute instabilities theory. From this model, the interfacial tension between the two phases can be calculated.

Aim: The study of the determinants of loss of autonomy during hospitalization may be valuable in the identification of the most effective interventions and to achieve better outcomes. The aim of this study was to describe changes in the level of autonomy of the elderly admitted to the hospital at the entrance and at discharge in relation to a rehabilitation program., Methods: Prospective observational study conducted at the INRCA Geriatric Hospital of Ancona. The study included patients aged 65 years and over, daily admitted to INRCA Hospital of Ancona between September and December 2010. Criteria for inclusion were age ≥ 65 years, length of stay > 24 hours and signed informed consent. Patients admitted for less than 24 hours or in day hospital or day surgery were excluded from the beginning. A total of 1266 elderly patients were recruited in the period. From this sample, 74 people who died during hospitalization were excluded. At the time of hospitalization (within 24 hours) and at discharge, patients were evaluated with the Barthel Index (BI), the Rankin scale, and a short assessment of cognitive status derived from the Mini Mental State Examination (MMSE)., Results: Referring to 1192 subjects who participated to the study, the mean age was 82.13 years ±7.39, age range between 65 and 100 years. The average BI was 56.6±36.16 (SD) (median value =60) at admission and 63.84±34.7 (SD) (median value=70) at discharge. The average Rankin score at admission was 2.63±1.5 (SD) (median value=3)., Conclusion: Patients presented better score of the BI at discharge and this figure was associated to the implementation of a rehabilitation treatment. Hospitalization of the elderly patient in a suitable environment, such as a geriatric hospital, contrary to some theories highlighting only the negative aspects of removal from the living environment, can be a measure of benefit for the reduction of disability and the recovery of compromised activities along and after the acute event. The collection of data on the level of autonomy of the subjects before and after hospitalization can be a useful element for clinical evaluation in a geriatric hospital.