Automated graded prognostic assessment for patients with hepatocellular carcinoma using machine learning.

BACKGROUND: Accurate mortality risk quantification is crucial for the management of hepatocellular carcinoma (HCC); however, most scoring systems are subjective. PURPOSE: To develop and independently validate a machine learning mortality risk quantification method for HCC patients using standard-of-care clinical data and liver radiomics on baseline magnetic resonance imaging (MRI). METHODS: This retrospective study included all patients with multiphasic contrast-enhanced MRI at the time of diagnosis treated at our institution. Patients were censored at their last date of follow-up, end-of-observation, or liver transplantation date. The data were randomly sampled into independent cohorts, with 85% for development and 15% for independent validation. An automated liver segmentation framework was adopted for radiomic feature extraction. A random survival forest combined clinical and radiomic variables to predict overall survival (OS), and performance was evaluated using Harrell's C-index. RESULTS: A total of 555 treatment-naïve HCC patients (mean age, 63.8 years ± 8.9 [standard deviation]; 118 females) with MRI at the time of diagnosis were included, of which 287 (51.7%) died after a median time of 14.40 (interquartile range, 22.23) months, and had median followed up of 32.47 (interquartile range, 61.5) months. The developed risk prediction framework required 1.11 min on average and yielded C-indices of 0.8503 and 0.8234 in the development and independent validation cohorts, respectively, outperforming conventional clinical staging systems. Predicted risk scores were significantly associated with OS (p < .00001 in both cohorts). CONCLUSIONS: Machine learning reliably, rapidly, and reproducibly predicts mortality risk in patients with hepatocellular carcinoma from data routinely acquired in clinical practice. CLINICAL RELEVANCE STATEMENT: Precision mortality risk prediction using routinely available standard-of-care clinical data and automated MRI radiomic features could enable personalized follow-up strategies, guide management decisions, and improve clinical workflow efficiency in tumor boards. KEY POINTS: • Machine learning enables hepatocellular carcinoma mortality risk prediction using standard-of-care clinical data and automated radiomic features from multiphasic contrast-enhanced MRI. • Automated mortality risk prediction achieved state-of-the-art performances for mortality risk quantification and outperformed conventional clinical staging systems. • Patients were stratified into low, intermediate, and high-risk groups with significantly different survival times, generalizable to an independent evaluation cohort.

Elucidating the behavior of the SARS-CoV-2 virus surface at vapor-liquid interfaces using molecular dynamics simulation.

Aerosols play a major role in the transmission of the SARS-CoV-2 virus. The behavior of the virus within aerosols is therefore of fundamental importance. On the surface of a SARS-CoV-2 virus, there are about 40 spike proteins, which each have a length of about 20 nm. They are glycosylated trimers, which are highly flexible, due to their structure. These spike proteins play a central role in the intrusion of the virus into human host cells and are, therefore, a focus of vaccine development. In this work, we have studied the behavior of spike proteins of the SARS-CoV-2 virus in the presence of a vapor-liquid interface by molecular dynamics (MD) simulations. Systematically, the behavior of the spike protein at different distances to a vapor-liquid interface were studied. The results reveal that the spike protein of the SARS-CoV-2 virus is repelled from the vapor-liquid interface and has a strong affinity to stay inside the bulk liquid phase. Therefore, the spike protein bends when a vapor-liquid interface approaches the top of the protein. This has important consequences for understanding the behavior of the virus during the dry-out of aerosol droplets.

Percutaneous Computed Tomography (CT) Fluoroscopy-Guided Biopsy of the Spleen Using Fibrin Glue as a Sealant.

Some authors consider the risk of bleeding an absolute contraindication to percutaneous image-guided splenic puncture. While splenic punctures are mainly performed at specialized centers, no technique for the closure of the puncture tract has been broadly established. The aim of this study was to investigate the effectiveness and safety of a percutaneous image-guided biopsy of the spleen using fibrin glue to plug the tract. A total of 27 requests for splenic image-guided interventions were identified between 2010 and 2021 and considered for inclusion in our retrospective single-center study. Seven patients needed to be excluded, which left twenty patients who underwent a percutaneous computed tomography (CT) fluoroscopy-guided biopsy of a splenic lesion during this period. In all patients, a 17G coaxial needle with an 18G core biopsy needle was used. Diagnostic adequacy and accuracy were evaluated, and complications were classified using the CIRSE classification system for adverse events. Diagnostic adequacy was 100% (20/20), and a median of four samples were collected. Diagnostic accuracy was 80% (16/20). The four off-target samples included one inconclusive finding and three samples of regular spleen tissue. The overall complication rate was 5% (1/20). No mild (grade 1-2) or moderate (grade 3-4) complications occurred. One severe (grade 5-6) complication occurred. Although controversial and potentially high-risk, diagnostic percutaneous biopsies of the spleen appear to be relatively safe with the use of fibrin glue to seal the tract.

Percutaneous drainage and combined praziquantel-albendazole therapy: a novel approach for the treatment of simple echinococcal liver cysts.

Cystic echinococcosis (CE) is a worldwide helminthic zoonosis causing serious disease in humans. The WHO Informal Working Group on Echinococcosis recommends a stage-specific treatment approach of hepatic CE that facilitates the decision on what therapy option is most appropriate. Percutaneous aspiration, instillation of a scolicide, e.g., ethanol or hypertonic saline, and subsequent re-aspiration (PAIR) have been advocated for treating medium-size unilocular WHO-stage CE1 cysts. PAIR can pose a risk of toxic cholangitis because of spillage of ethanol in the case of a cysto-biliary fistula or of life-threatening hypernatriaemia when hypertonic saline is used. The purpose of our study is to develop an alternative, safe, minimally invasive method to treat CE1 cysts, avoiding the use of toxic topic scolicides.We opt for percutaneous drainage (PD) in four patients: the intrahepatic drainage catheter is placed under CT-fluoroscopy, intracystic fluid is aspirated, and the viability of intracystic echinococcal protoscolices is assessed microscopically. Oral praziquantel (PZQ) is added to albendazole (ABZ) instead of using topical scolicidals.Protoscolices degenerate within 5 to 10 days after PZQ co-medication at a cumulative dosage of 250 to 335 mg/kg, and the cysts collapse. The cysts degenerate, and no sign of spillage nor relapse is observed in the follow-up time of up to 24 months post-intervention.In conclusion, PD combined with oral PZQ under ABZ coverage is preferable to PAIR in patients with unilocular echinococcal cysts.

The dual pro-inflammatory and bone-protective role of calcitonin gene-related peptide alpha in age-related osteoarthritis.

BACKGROUND: The vasoactive neuropeptide calcitonin gene-related peptide alpha (αCGRP) enhances nociception in primary knee osteoarthritis (OA) and has been shown to disrupt cartilage and joint integrity in experimental rheumatoid arthritis (RA). Little is known about how αCGRP may alter articular structures in primary OA. We investigated whether αCGRP modulates local inflammation and concomitant cartilage and bone changes in a murine model of age-dependent OA. METHODS: Sixteen- to 18-month-old αCGRP-deficient mice (αCGRP-/-aged) were compared to, first, age-matched wild type (WTaged) and, second, young 4- to 5-month-old non-OA αCGRP-deficient (αCGRP-/-CTRL) and non-OA WT animals (WTCTRL). αCGRP levels were measured in serum. Knee and hip joint inflammation, cartilage degradation, and bone alterations were assessed by histology (OARSI histopathological grading score), gene expression analysis, and µ-computed tomography. RESULTS: WTaged mice exhibited elevated αCGRP serum levels compared to young WTCTRL animals. Marked signs of OA-induced cartilage destruction were seen in WTaged animals, while αCGRP-/-aged mice were mostly protected from this effect. Age-dependent OA was accompanied by an increased gene expression of pro-inflammatory Tnfa, Il1b, and Il6 and catabolic Mmp13, Adamts5, Ctsk, Tnfs11 (Rankl), and Cxcl12/Cxcr4 in WTaged but not in αCGRP-/-aged mice. αCGRP-deficiency however further aggravated subchondral bone sclerosis of the medial tibial plateau and accelerated bone loss in the epi- and metaphyseal trabecular tibial bone in age-dependent OA. CONCLUSIONS: Similar to its function in experimental RA, αCGRP exerts a dual pro-inflammatory and bone-protective function in murine primary OA. Although anti-CGRP treatment was previously not successful in reducing pain in OA clinically, these data underline a crucial pathophysiological role of αCGRP in age-related OA.

Extension of the MolMod Database to Transferable Force Fields.

MolMod, a web-based database for classical force fields for molecular simulations of fluids [Mol. Sim. 45, 10 (2019), 806-814], was extended to transferable force fields. Eight transferable force fields, including all-atom and united-atom type force fields, were implemented in the MolMod database: OPLS-UA, OPLS-AA, COMPASS, CHARMM, GROMOS, TraPPE, Potoff, and TAMie. These transferable force fields cover a large variety of chemical substance classes. The system is designed such that new transferable force fields can be readily integrated. A graphical user interface was implemented that enables the construction of molecules. The MolMod database compiles the force field for the specified component and force field type and provides the corresponding data and meta data as well as ready-to-use input files for the molecule for different simulation engines. This helps the user to flexibly choose molecular models and integrate them swiftly in their individual workflows, reducing risks of input errors in molecular simulations.

Data scheme and data format for transferable force fields for molecular simulation.

A generalized data scheme for transferable classical force fields used in molecular simulations, i.e. molecular dynamics and Monte Carlo simulation, is presented. The data scheme is implemented in an SQL-based data format. The data scheme and data format is machine readable, re-usable, and interoperable. A transferable force field is a chemical construction plan specifying intermolecular and intramolecular interactions between different types of atoms or different chemical groups and can be used for building a model for a given component. The data scheme proposed in this work (named TUK-FFDat) formalizes digitally these chemical construction plans, i.e. transferable force fields. It can be applied to all-atom as well as united-atom transferable force fields. The general applicability of the data scheme is demonstrated for different types of force fields (TraPPE, OPLS-AA, and Potoff). Furthermore, conversion tools for translating the data scheme between .xls spread sheet format and the SQL-based data format are provided. The data format can readily be integrated in existing workflows, simulation engines, and force field databases as well as for linking such.

Medical historical notes on myoma treatment by uterine artery embolization on the occasion of its introduction 30 years ago. / Medizinhistorische Anmerkungen zur Myombehandlung mittels Uterusarterienembolisation aus Anlass ihrer Einführung vor 30 Jahren.

BACKGROUND: Since its development, uterine artery embolization (UAE) for the treatment of symptomatic fibroids has become an established minimally invasive alternative to surgical myoma treatment. Currently, more than 25,000 myoma patients worldwide are likely to be treated with UAE annually. METHOD: Thirty years ago, Jacques-Henri Ravina (b. 1930) and his Paris team first performed this therapy as a "substitute" for gynecologic surgery. We contacted him as part of the preparation of the present review. In addition, we performed a literature search with the aim of summarizing the current literature and data in addition to a historical account of the development of UAE. RESULTS AND CONCLUSION: On the occasion of this anniversary, we would like to recall the interdisciplinary roots and some facets of the history of the development of this relatively young myoma treatment method. KEY POINTS: · UAE is an established minimally invasive alternative to surgical myoma treatment.. · UAE was first developed 30 years ago.. · UAE has continuously increased in importance in recent years.. CITATION FORMAT: · Psilopatis I, Fleckenstein FN, Gebauer B et al. Medical historical notes on myoma treatment by uterine artery embolization on the occasion of its introduction 30 years ago. Fortschr Röntgenstr 2023; 195: 890 - 895.

The Emerging Role of Histone Deacetylase Inhibitors in Cervical Cancer Therapy.

Cervical carcinoma is one of the most common cancers among women globally. Histone deacetylase inhibitors (HDACIs) constitute anticancer drugs that, by increasing the histone acetylation level in various cell types, induce differentiation, cell cycle arrest, and apoptosis. The aim of the current review is to study the role of HDACIs in the treatment of cervical cancer. A literature review was conducted using the MEDLINE and LIVIVO databases with a view to identifying relevant studies. By employing the search terms "histone deacetylase" and "cervical cancer", we managed to identify 95 studies published between 2001 and 2023. The present work embodies the most up-to-date, comprehensive review of the literature centering on the particular role of HDACIs as treatment agents for cervical cancer. Both well-established and novel HDACIs seem to represent modern, efficacious anticancer drugs, which, alone or in combination with other treatments, may successfully inhibit cervical cancer cell growth, induce cell cycle arrest, and provoke apoptosis. In summary, histone deacetylases seem to represent promising future treatment targets in cervical cancer.

The Impact of Histone Modifications in Endometriosis Highlights New Therapeutic Opportunities.

Endometriosis is a chronic disorder of the female reproductive system which afflicts a great number of women worldwide. Histone deacetylases (HDACs) prevent the relaxation of chromatin, thereby positively or negatively modulating gene transcription. The current review aims at studying the impact of histone modifications and their therapeutic targeting in endometriosis. In order to identify relevant studies, a literature review was conducted using the MEDLINE and LIVIVO databases. The current manuscript represents the most comprehensive, up-to-date review of the literature focusing on the particular role of HDACs and their inhibitors in the context of endometriosis. HDAC1, HDAC2, HDAC3, Sirtuin 1, and Sirtuin 3, are the five most studied HDAC enzymes which seem to, at least partly, influence the pathophysiology of endometriosis. Both well-established and novel HDACIs could possibly represent modern, efficacious anti-endometriotic drug agents. Altogether, histone modifications and their therapeutic targeting have been proven to have a strong impact on endometriosis.

The Role of Peroxisome Proliferator-Activated Receptors in Preeclampsia.

Preeclampsia is a common pregnancy-related hypertensive disorder. Often presenting as preexisting or new-onset hypertension complicated by proteinuria and/or end-organ dysfunction, preeclampsia significantly correlates with maternal and perinatal morbidity and mortality. Peroxisome proliferator-activated receptors (PPARs) are nuclear receptor proteins that regulate gene expression. In order to investigate the role of PPARs in the pathophysiology of preeclampsia, we conducted a literature review using the MEDLINE and LIVIVO databases. The search terms "peroxisome proliferator-activated receptor", "PPAR", and "preeclampsia" were employed and we were able to identify 35 relevant studies published between 2002 and 2022. Different study groups reached contradictory conclusions in terms of PPAR expression in preeclamptic placentae. Interestingly, PPARγ agonists alone, or in combination with well-established pharmaceutical agents, were determined to represent novel, potent anti-preeclamptic treatment alternatives. In conclusion, PPARs seem to play a significant role in preeclampsia.

Comparison of Force Fields for the Prediction of Thermophysical Properties of Long Linear and Branched Alkanes.

The prediction of thermophysical properties at extreme conditions is an important application of molecular simulations. The quality of these predictions primarily depends on the quality of the employed force field. In this work, a systematic comparison of classical transferable force fields for the prediction of different thermophysical properties of alkanes at extreme conditions, as they are encountered in tribological applications, was carried out using molecular dynamics simulations. Nine transferable force fields from three different classes were considered (all-atom, united-atom, and coarse-grained force fields). Three linear alkanes (n-decane, n-icosane, and n-triacontane) and two branched alkanes (1-decene trimer and squalane) were studied. Simulations were carried out in a pressure range between 0.1 and 400 MPa at 373.15 K. For each state point, density, viscosity, and self-diffusion coefficient were sampled, and the results were compared to experimental data. The Potoff force field yielded the best results.

Individual immune cell and cytokine profiles determine platelet-rich plasma composition.

OBJECTIVE: Platelet-rich plasma (PRP) therapy is increasingly popular to treat musculoskeletal diseases, including tendinopathies and osteoarthritis (OA). To date, it remains unclear to which extent PRP compositions are determined by the immune cell and cytokine profile of individuals or by the preparation method. To investigate this, we compared leukocyte and cytokine distributions of different PRP products to donor blood samples and assessed the effect of pro-inflammatory cytokines on chondrocytes. DESIGN: For each of three PRP preparations (ACP®, Angel™, and nSTRIDE® APS), products were derived using whole blood samples from twelve healthy donors. The cellular composition of PRP products was analyzed by flow cytometry using DURAClone antibody panels (DURAClone IM Phenotyping Basic and DURAClone IM T Cell Subsets). The MESO QuickPlex SQ 120 system was used to assess cytokine profiles (V-PLEX Proinflammatory Panel 1 Human Kit, Meso Scale Discovery). Primary human chondrocyte 2D and 3D in vitro cultures were exposed to recombinant IFN-γ and TNF-α. Proliferation and chondrogenic differentiation were quantitatively assessed. RESULTS: All three PRP products showed elevated portions of leukocytes compared to baseline levels in donor blood. Furthermore, the pro-inflammatory cytokines IFN-γ and TNF-α were significantly increased in nSTRIDE® APS samples compared to donor blood and other PRP products. The characteristics of all other cytokines and immune cells from the donor blood, including pro-inflammatory T cell subsets, were maintained in all PRP products. Chondrocyte proliferation was impaired by IFN-γ and enhanced by TNF-α treatment. Differentiation and cartilage formation were compromised upon treatment with both cytokines, resulting in altered messenger ribonucleic acid (mRNA) expression of collagen type 1A1 (COL1A1), COL2A1, and aggrecan (ACAN) as well as reduced proteoglycan content. CONCLUSIONS: Individuals with elevated levels of cells with pro-inflammatory properties maintain these in the final PRP products. The concentration of pro-inflammatory cytokines strongly varies between PRP products. These observations may help to unravel the previously described heterogeneous response to PRP in OA therapy, especially as IFN-γ and TNF-α impacted primary chondrocyte proliferation and their characteristic gene expression profile. Both the individual's immune profile and the concentration method appear to impact the final PRP product. TRIAL REGISTRATION: This study was prospectively registered in the Deutsches Register Klinischer Studien (DRKS) on 4 November 2021 (registration number DRKS00026175).

Quality and quantity of serious violent suicide attempts during the COVID-19 pandemic.

Background: While repeated shutdown and lockdown measures helped contain the spread of SARS-CoV-2 during the COVID-19 pandemic, social distancing and self-isolation negatively impacted global mental health in 2020 and 2021. Although suicide rates did reportedly not increase during the first months of the pandemic, long-term data, and data on the quality of serious violent suicide attempts (SVSAs) are not available to date. Materials and methods: Orthopaedic trauma patient visits to the emergency department (ED), ED trauma team activations, and SVSAs were retrospectively evaluated from January 2019 until May 2021 in four Level-I Trauma Centers in Berlin, Germany. SVSAs were assessed for suicide method, injury pattern and severity, type of treatment, and length of hospital stay. Results: Significantly fewer orthopaedic trauma patients presented to EDs during the pandemic (n = 70,271) compared to the control (n = 84,864) period (p = 0.0017). ED trauma team activation numbers remained unchanged. SVSAs (corrected for seasonality) also remained unchanged during control (n = 138) and pandemic (n = 129) periods, and no differences were observed for suicide methods, injury patterns, or length of hospital stay. Conclusion: Our data emphasize that a previously reported rise in psychological stress during the COVID-19 pandemic does not coincide with increased SVSA rates or changes in quality of SVSAs.

Short- and long-term evaluation of disease-specific symptoms and quality of life following uterine artery embolization of fibroids.

BACKGROUND: The purpose of this study is to evaluate uterine artery embolization (UAE) for the management of symptomatic uterine leiomyomas regarding changes in quality of life after treatment in a large patient collective. This study retrospectively analyzed prospectively acquired standardized questionnaires of patients treated with UAE. Clinical success was evaluated before and after embolization. Patients were stratified into short- (≤ 7 months) and long-term (> 7 months) follow-up groups depending on the time of completion of the post-interventional questionnaire. Uterine leiomyomas were furthermore divided into small (< 10 cm) and large (≥ 10 cm) tumors based on the diameter of the dominant fibroid. RESULTS: A total of 245 patients were included into the final data analysis. The Kaplan-Meier analysis showed a cumulative clinical success rate of 75.8% after 70 months until the end of follow-up (9.9 years). All questionnaire subscales showed a highly significant clinical improvement from baseline to short- and long-term follow-up (p < 0.001). Patients with small fibroids showed a significantly better response to UAE in multiple subcategories of the questionnaire than patients with fibroids ≥ 10 cm who had a twofold higher probability of re-intervention in the Cox-regression model. CONCLUSIONS: UAE is an effective treatment method for symptomatic fibroids that leads to quick relief of fibroid-related symptoms with marked improvement of quality of life and is associated with a low risk for re-interventions. Patients with small fibroids tend to show a better response to UAE compared to patients with large fibroids. Trial registration Charité institutional review board, EA4/167/20. Registered 27 November 2020-Retrospectively registered. https://ethikkommission.charite.de/.

CT fluoroscopy-guided percutaneous gastrostomy (CT-PG) - A single center experience in 233 patients.

PURPOSE: To investigate the feasibility and complications of computed tomography-guided percutaneous gastroscopy (CT-PG) using two procedural techniques (trocar technique and Seldinger technique) in all patients and in a subgroup of patients with ascites as a relative contraindication. MATERIAL AND METHODS: In this single-center study a total of 233 patients who underwent CT-PG (55 in trocar group and 178 in Seldinger group) between 2012 and 2021 were analyzed retrospectively. Success and complications were determined for both techniques and compared in the total study population and in the subgroup of patients with ascites. Complications were classified using the Common Terminology Criteria for Adverse Events (CTCAE) Protocol for procedural complications. RESULTS: Feeding tube placement was successful in 93.6% of cases (218/233). In the trocar group, placement was successful in 98.2% (54/55) with a complication rate of 7.4% (4/54) including one grade 5 complication. In the Seldinger group, placement was successful in 92.1% (164/178) with a complication rate of 6.7% but no grade 4 or 5 complication. Preprocedural paracentesis for ascites was performed in 6.9% of patients (16/233). In this subgroup, CT-PG was successful in 87.5% (14/16) and only complications rated as grade 1 or 2 occurred. CONCLUSION: CT-PG is a safe interventional procedure, which also applies to patients with ascites if paracentesis is performed beforehand. Specifically, our findings show the Seldinger technique to be safe, as no severe complications occurred in this subgroup.

A prospective randomized controlled trial assessing the effect of music on patients' anxiety in venous catheter placement procedures.

The aim of the study was to assess the influence of music on anxiety levels compared to standard patient care in patients undergoing venous catheter placement procedures. This prospective randomized controlled trial included patients undergoing placement procedures for peripherally inserted central venous catheters (PICC), ports and central venous catheters (CVC). Patients were randomly assigned to a music intervention group (MIG) and a control group (CTRL). State and trait anxiety levels were assessed as primary outcome using the state-trait anxiety inventory (STAI) before and after the procedures. Secondary outcomes comprised averaged heart rate for all participants and time of radiological surveillance for port placement procedures exclusively. 72 participants were included into the final analysis (MIG n = 40; CTRL n = 32). All procedures were successful and no major complications were reported. Mean levels for post-interventional anxieties were significantly lower in the MIG compared to the CTRL (34.9 ± 8.9 vs. 44 ± 12.1; p < 0.001). Mean heart rate in the MIG was significantly lower than in the CTRL (76.1 ± 13.7 vs. 93 ± 8.9; p < 0.001). Procedure time for port implantation was significantly longer in the MIG by 3 min 45 s (p = 0.031). Music exposure during central venous catheter placement procedures highly significantly reduces anxiety and stress levels and can be used to improve patients' overall experience in the angio suite.

Source and hub of inflammation: The infrapatellar fat pad and its interactions with articular tissues during knee osteoarthritis.

Knee osteoarthritis, the most prevalent degenerative joint disorder worldwide, is driven by chronic low-grade inflammation and subsequent cartilage degradation. Clinical data on the role of the Hoffa or infrapatellar fat pad in knee osteoarthritis are, however, scarce. The infrapatellar fat pad is a richly innervated intracapsular, extrasynovial adipose tissue, and an abundant source of adipokines and proinflammatory and catabolic cytokines, which may contribute to chronic synovial inflammation, cartilage destruction, and subchondral bone remodeling during knee osteoarthritis. How the infrapatellar fat pad interacts with neighboring tissues is poorly understood. Here, we review available literature with regard to the infrapatellar fat pad's interactions with cartilage, synovium, bone, menisci, ligaments, and nervous tissue during the development and progression of knee osteoarthritis. Signaling cascades are described with a focus on immune cell populations, pro- and anti-inflammatory cytokines, adipokines, mesenchymal stromal cells, and molecules derived from conditioned media from the infrapatellar fat pad. Understanding the complex interplay between the infrapatellar fat pad and its neighboring articular tissues may help to better understand and treat the multifactorial pathogenesis of osteoarthritis.

Splenic artery steal syndrome in patients with orthotopic liver transplant: Where to embolize the splenic artery?

PURPOSE: This study compared proximal and distal embolization of the splenic artery (SA) in patients with splenic artery steal syndrome (SAS) after orthotopic liver transplantation (OLT) regarding post interventional changes of liver function to identify an ideal location of embolization. METHODS AND MATERIALS: 85 patients with SAS after OLT treated with embolization of the SA between 2007 and 2017 were retrospectively reviewed. Periinterventional DSA was used to assess treatment success and to stratify patients according to the site of embolization. Liver function was assessed using following laboratory values: bilirubin, albumin, gamma-glutamyl transferase, glutamat-pyruvat-transaminase (GPT), glutamic-oxaloacetic transaminase (GOT), Alkaline Phosphatase (ALP), aPTT, prothrombin time and thrombocyte count. Descriptive statistics were used to summarize the data. Median laboratory values of pre, 1- and 3-days, as well as 1-week and 1-month post-embolization were compared between the respective embolization sites using linear mixed model regression analysis. RESULTS: All procedures were technically successful and showed an improved blood flow in the hepatic artery post-embolization. Ten Patients were excluded due to re -intervention or inconsistent image documentation. Pairwise comparison using linear mixed model regression analysis showed a significant difference between proximal and distal embolization for GPT (57.0 (IQR 107.5) vs. 118.0 (IQR 254.0) U/l, p = 0.002) and GOT (48.0 (IQR 48.0) vs. 81.0 (IQR 115.0) U/l, p = 0.008) 3-days after embolization as well as median thrombocyte counts 7-days after embolization (122 (IQR 108) vs. 83 (IQR 74) in thousands, p = 0.014). For all other laboratory values, no statistically significant difference could be shown with respect to the embolization site. CONCLUSION: We conclude that long-term outcomes after embolization of the SA in the scenario of SAS after OLT are irrespective of the site of embolization of the SA, whereas a proximal embolization potentially facilitates earlier normalization of liver function. Choice of technique should therefore be informed by anatomical conditions, safety considerations and preferences of the interventionalist.

Changes of radiological examination volumes over the course of the COVID-19 pandemic: a comprehensive analysis of the different waves of infection.

OBJECTIVES: Data from radiological departments provide important information on overall quantities of medical care provided. With this study we used a comprehensive analysis of radiological examinations as a surrogate marker to quantify the effect of the different COVID-19 waves on medical care provided. METHODS: Radiological examination volumes during the different waves of infection were compared among each other as well as to time-matched control periods from pre-pandemic years using a locally weighted scatterplot smoothing as well as negative binominal regression models. RESULTS: A total of 1,321,119 radiological examinations were analyzed. Examination volumes were reduced by about 10% over the whole study period (IRR = 0.90; 95% CI 0.89-0.92), with a focus on acute medical care (0.84; 0.83-0.85) and outpatients (0.93: 0.90-0.97). When compared to wave 1, examination volumes were about 17% higher during wave 2 (1.17; 1.10-1.25), and 33% higher in wave 3 of the pandemic (1.33; 1.24-1.42). CONCLUSIONS: This study shows the severe effect of COVID-19 pandemic and related shutdown measures on overall provided medical care as measured by radiological examinations. When compared, the decrease of medical care was more pronounced in the earlier waves of the pandemic.