An enteric ultrastructural surface atlas of the model insect Manducasexta

The tobacco hornworm is a laboratory model that is particularly suitable for analyzing gut inflammation, but a physiological reference standard is currently unavailable. Here, we present a surface atlas of the healthy hornworm gut generated by scanning electron microscopy and nano-computed tomography. This comprehensive overview of the gut surface reveals morphological differences between the anterior, middle, and posterior midgut, allowing the screening of aberrant gut phenotypes while accommodating normal physiological variations. We estimated a total resorptive midgut surface of 0.42 m2 for L5d6 larvae, revealing its remarkable size. Our data will support allometric scaling and dose conversion from Manduca sexta to mammals in preclinical research, embracing the 3R principles. We also observed non-uniform gut colonization by enterococci, characterized by dense biofilms in the pyloric cone and downstream of the pylorus associated with pore and spine structures in the hindgut intima, indicating a putative immunosurveillance function in the lepidopteran hindgut.

Evaluation of Mechanical Versus Manual Root Canal Preparation in Primary Molars-A Comparative In Vitro Study

The endodontic treatment of primary teeth is to maintain the function of the tooth free of symptoms until its physiological exfoliation. A critical factor for success is how quickly and effectively the root canal preparation can be performed. Therefore, the aim of this comparative in vitro study was to analyze the efficiency of two mechanical root canal preparation systems FM (FlexMaster) and HF (HyFlex EDM) to manual KF (K-file) on extracted primary molars. A total of 45 teeth were divided into three groups (n = 15): KF (#15-35), FM (04#30) and HF (25/~ OneFile). Root canal preparation was performed, and the preparation time was measured. All root canals were non-destructively analyzed by micro-computed tomography in the cervical, middle and apical thirds before and after preparation with regard to the parameters of canal transport (in μm) and centering ratio (0-1). Statistical analysis was performed at a 5% significance level using non-parametric tests. HF caused the lowest canal transport in the apical third (p = 0.008). The centering ratio value of HF was significantly higher in the middle third of the root canals than in the other two groups (p < 0.01). The mean instrumentation time was significantly higher for KF (6.67 min) than for FM (4.69 min) and HF (4.03 min, p < 0.01). HF can be recommended for primary molar root canal treatment.

Controversial Aspects of Diagnostics and Therapy of Idiopathic Condylar Resorption: An Analysis of Evidence- and Consensus-Based Recommendations Based on an Interdisciplinary Guideline Project

Idiopathic condylar resorption (ICR), though a rare event, is associated with severe detrimental sequelae for the patient. To date, the etiology remains unknown, and treatment strategies are highly controversial. Therefore, the aim of this study is to present an analysis of the consensus- and evidence-based approach to ICR by a German interdisciplinary guideline project of the AWMF (Association of the Scientific Medical Societies in Germany). Following a systematic literature search, including 56 (out of an initial 97) publications, with a predominantly low level of evidence (LoE), two independent working groups (oral and maxillofacial surgery and interdisciplinary, respectively) voted on a draft comprising 25 recommendations in a standardized anonymized and blinded Delphi procedure. While the results of the votes were relatively homogeneous, the interdisciplinary phase required a significantly higher number of rounds (p < 0.001). Most of the controversial recommendations were related to initial imaging (with consensus on CT/CBCT as the current diagnostic standard for imaging), pharmacotherapy (no recommendation due to lack of evidence), discopexy (no recommendation possible due to low LoE) and timing of orthognathic surgery (with consensus on two-staged procedures after invasive TMJ surgery, except for single-stage procedures if combined with total joint reconstruction). Overall, the Delphi procedure resulted in an interdisciplinary guideline offering the best possible evidence- and consensus-based expertise to date in the diagnosis and treatment of ICR.

Feasibility of periprocedural decision on the administration of intravenous contrast media in MRI for endometriosis

PURPOSE

To assess the feasibility of a periprocedural decision on the administration of intravenous contrast media in MRI for endometriosis and to evaluate the frequency and reasons of contrast administrations, the corresponding MRI diagnoses, and outcome.

METHODS

In this retrospective, descriptive cross-sectional single-center study all patients were included, who received a pelvic MRI for evaluation of endometriosis between April 2021 and February 2023. Frequency and reasons of optional intravenous administration of contrast media, corresponding MRI diagnoses and clinical outcome data were noted after re-review of all images, review of radiology reports and review of patients' medical records. The decision on the administration of intravenous contrast media had been made by experienced radiologists, depending on the findings of the non-contrast sequences and the presence of ancillary questions.

RESULTS

303 consecutive patients (mean age, 33.4 years +/- 8.3 [standard deviation]) were evaluated. Periprocedural decision on the administration of intravenous contrast media had been made in all cases. For 219/303 (72.3%) patients, it was decided after review of the non-contrast sequences and exclusion of ancillary questions that contrast administration was not required. 84/303 (27.7%) patients received contrast media, and the most frequent reasons were indeterminate ovarian lesion (41/84 cases, 48.8%) or suspicion of pelvic venous congestion syndrome (26/84 cases, 31.0%). No relevant differences in patient outcomes could be noted (non-contrast/contrast MRI).

CONCLUSIONS

A periprocedural decision on the administration of contrast media in MRI for endometriosis is feasible with little effort. It allows the administration of contrast media to be avoided in most cases. If the administration of contrast media is deemed necessary, repeat examinations can be avoided.

A quantitative micro-tomographic gut atlas of the lepidopteran model insect Manduca sexta

The tobacco hornworm is used extensively as a model system for ecotoxicology, immunology and gut physiology. Here, we established a micro-computed tomography approach based on the oral application of the clinical contrast agent iodixanol, allowing for a high-resolution quantitative analysis of the Manduca sexta gut. This technique permitted the identification of previously unknown and understudied structures, such as the crop or gastric ceca, and revealed the underlying complexity of the hindgut folding pattern, which is involved in fecal pellet formation. The acquired data enabled the volume rendering of all gut parts, the reliable calculation of their volumes, and the virtual endoscopy of the entire alimentary tract. It can provide information for accurate orientation in histology uses, enable quantitative anatomical phenotyping in three dimensions, and allow the calculation of locally effective midgut concentrations of applied chemicals. This atlas will provide critical insights into the evolution of the alimentary tract in lepidopterans.

Analysis of fixation materials in micro-CT: It doesn't always have to be styrofoam

Good fixation of filigree specimens for micro-CT examinations is often a challenge. Movement artefacts, over-radiation or even crushing of the specimen can easily occur. Since different specimens have different requirements, we scanned, analysed and compared 19 possible fixation materials under the same conditions in the micro-CT. We focused on radiodensity, porosity and reversibility of these fixation materials. Furthermore, we have made sure that all materials are cheap and easily available. The scans were performed with a SkyScan 1173 micro-CT. All dry fixation materials tested were punched into 5 mm diameter cylinders and clamped into 0.2 ml reaction vessels. A voxel size of 5.33 μm was achieved in a 180° scan in 0.3° steps. Ideally, fixation materials should not be visible in the reconstructed image, i.e., barely binarised. Besides common micro-CT fixation materials such as styrofoam (-935 Hounsfield Units) or Basotect foam (-943 Hounsfield Units), polyethylene air cushions (-944 Hounsfield Units), Micropor foam (-926 Hounsfield Units) and polyurethane foam, (-960 Hounsfield Units to -470 Hounsfield Units) have proved to be attractive alternatives. Furthermore, more radiopaque materials such as paraffin wax granulate (-640 Hounsfield Units) and epoxy resin (-190 Hounsfield Units) are also suitable as fixation materials. These materials often can be removed in the reconstructed image by segmentation. Sample fixations in the studies of recent years are almost all limited to fixation in Parafilm, Styrofoam, or Basotect foam if the fixation type is mentioned at all. However, these are not always useful, as styrofoam, for example, dissolves in some common media such as methylsalicylate. We show that micro-CT laboratories should be equipped with various fixation materials to achieve high-level image quality.

Deep Infiltrating Endometriosis: Diagnostic Accuracy of Preoperative Magnetic Resonance Imaging with Respect to Morphological Criteria

Several current guidelines recommend imaging in the diagnostic work-up of deep infiltrating endometriosis (DIE). The purpose of this retrospective diagnostic test study was to evaluate the diagnostic accuracy of MRI compared to laparoscopy for the identification of pelvic DIE, considering lesion morphology using MRI. In all, 160 consecutive patients were included who received pelvic MRI for evaluation of endometriosis between October 2018 and December 2020 and underwent subsequent laparoscopy within 12 months of the MRI examination. MRI findings were categorized for suspected DIE using the Enzian classification and were additionally graded using a newly suggested deep infiltrating endometriosis morphology score (DEMS). Endometriosis was diagnosed in 108 patients (all types, i.e., purely superficial and DIE), of which 88 cases were diagnosed with DIE and 20 with solely superficial peritoneal endometriosis (i.e., not deep infiltrating endometriosis/DIE). The overall positive and negative predictive values of MRI for the diagnosis of DIE, including lesions with assumed low and medium certainty of DIE on MRI (DEMS 1-3), were 84.3% (95% CI: 75.3-90.4) and 67.8% (95% CI: 60.6-74.2), respectively, and 100.0% and 59.0% (95% CI: 54.6-63.3) when strict MRI diagnostic criteria were applied (DEMS 3). Overall sensitivity of MRI was 67.0% (95% CI: 56.2-76.7), specificity was 84.7% (95% CI: 74.3-92.1), accuracy was 75.0% (95% CI: 67.6-81.5), positive likelihood ratio (LR+) was 4.39 (95% CI: 2.50-7.71), negative likelihood ratio (LR-) was 0.39 (95% CI: 0.28-0.53), and Cohen's kappa was 0.51 (95% CI: 0.38-0.64). When strict reporting criteria are applied, MRI can serve as a method to confirm clinically suspected DIE.

Value of Right and Left Ventricular T1 and T2 Blood Pool Mapping in Patients with Chronic Thromboembolic Hypertension before and after Balloon Pulmonary Angioplasty

BACKGROUND

Parametric imaging has taken a steep rise in recent years and non-cardiac applications are of increasing interest. Therefore, the aim of our study was to assess right (RV) and left ventricular (LV) blood pool T1 and T2 values in patients with chronic thromboembolic pulmonary hypertension (CTEPH) compared to control subjects and their correlation to pulmonary hemodynamic.

METHODS

26 patients with CTEPH (mean age 64.8 years ± 12.8 SD; 15 female), who underwent CMR and right heart catheterization (RHC) before and 6-months after balloon pulmonary angioplasty (BPA), were retrospectively included. Ventricular blood pool values were measured, compared to control subjects (mean age 40.5 years ± 12.8 SD; 16 female) and correlated to invasive measures (CI, mPAP, PVR).

RESULTS

In both, control subjects and CTEPH patients, RVT1 and RVT2 were significantly reduced compared to LVT1 and LVT2. Compared to control subjects, RVT2 was significantly reduced in CTEPH patients (p = 0.0065) and increased significantly after BPA (p = 0.0048). Moreover, RVT2 was positively correlated with CI and negatively correlated with mPAP and PVR before (r = 0.5155, r = -0.2541, r = -0.4571) and after BPA (r = 0.4769, r = -0.2585, r = -0.4396).

CONCLUSION

Ventricular blood pool T2 mapping might be novel non-invasive CMR imaging marker for assessment of disease severity, prognosis, follow-up and even therapy monitoring in PH.

Sarcopenia of kidney transplant recipients as a predictive marker for reduced graft function and graft survival after kidney transplantation

PURPOSE

The association between sarcopenia of kidney transplant recipients and outcome after kidney transplantation (KT) has not yet been fully understood and is still considered controversial. The aim of our study was to analyze the impact of pre-transplant sarcopenia on graft function, postoperative complication rates, and survival of the patients after renal transplantation.

METHODS

In this retrospective single-center study, all patients who underwent KT (01/2013-12/2017) were included. Demographic data, rejection rates, delayed graft function, and graft and patient survival rates were analyzed. Sarcopenia was measured in computed tomography images by the sex-adjusted Hounsfield unit average calculation (HUAC).

RESULTS

During the study period, 111 single KTs (38 women and 73 men) were performed. Living donor kidney transplants were performed in 48.6%. In total, 32.4% patients had sarcopenia. Sarcopenic patients were significantly older (59.6 years vs. 49.8 years; p < 0.001), had a higher body mass index (BMI = 27.6 kg/m2 vs. 25.0 kg/m2; p = 0.002), and were more likely to receive deceased donor kidneys (72.2% vs. 41.3%; p = 0.002). Interestingly, 3 years after KT, the creatinine serum levels were significantly higher (2.0 mg/dl vs. 1.5 mg/dl; p = 0.001), whereas eGFR (39.9 ml/min vs. 53.4 ml/min; p = 0.001) and graft survival were significantly lower (p = 0.004) in sarcopenic transplant recipients. Sarcopenic patients stayed in hospital significantly longer postoperatively than those who were non-sarcopenic.

CONCLUSIONS

At the time of kidney transplantation, sarcopenia was found to predict reduced long-term graft function and diminished graft survival after KT. The early identification of sarcopenic patients can not only enable an optimized selection of recipients, but also the initiation of pre-habilitation programs during the waiting period.

Measuring Young's modulus of single trabeculae in cancellous bone using a two-point bending test

BACKROUND

Surgical treatment of proximal humeral fractures poses a major challenge, especially in osteoporotic bone. At present, there appears to exist neither a suitable model for research to optimize the osteosynthesis processes nor are the structural data available which are required for developing such a model. Therefore, the aim of this study is to determine the microscopic morphology and Young's modulus of cancellous bone from human humeral heads considering osteoporotic changes.

METHODS

Cylindrical samples were taken from ten fresh-frozen human humeral heads and structural analysis was done with μCT. Ten rod-like trabeculae were prepared from five of the humeral heads each which were measured and tested mechanically. For this purpose, the trabeculae were fixed on a slide and rotated axially under a stereo microscope. The sample cross-section and the depending moment of inertia were extracted from the image data. The samples were then loaded in a 2-point bending test and Young's moduli of the samples were determined.

RESULTS

It could be shown that with increasing age of the donor, ossified portion of the cancellous bone decreased (p < 0.05). The average degree of mineralization of the bone was 1.24 (±0.06) g/mm³, which decreased with increasing age (p < 0.05). The determined Young's modulus averaged 1.33 (±1.76) GPa.

INTERPRETATION

The verified structural parameter showed osteoporotic changes in the examined bone. This study for the first time determined Young's modulus of single trabeculae of cancellous bone of osteoporotically altered human humeral heads. Implementing the non-destructive sample measurement before exposure resulted in a methodical improvement.

High-throughput screening of caterpillars as a platform to study host-microbe interactions and enteric immunity

Mammalian models of human disease are expensive and subject to ethical restrictions. Here, we present an independent platform for high-throughput screening, using larvae of the tobacco hornworm Manduca sexta, combining diagnostic imaging modalities for a comprehensive characterization of aberrant phenotypes. For validation, we use bacterial/chemical-induced gut inflammation to generate a colitis-like phenotype and identify significant alterations in morphology, tissue properties, and intermediary metabolism, which aggravate with disease progression and can be rescued by antimicrobial treatment. In independent experiments, activation of the highly conserved NADPH oxidase DUOX, a key mediator of gut inflammation, leads to similar, dose-dependent alterations, which can be attenuated by pharmacological interventions. Furthermore, the developed platform could differentiate pathogens from mutualistic gastrointestinal bacteria broadening the scope of applications also to microbiomics and host-pathogen interactions. Overall, larvae-based screening can complement mammals in preclinical studies to explore innate immunity and host-pathogen interactions, thus representing a substantial contribution to improve mammalian welfare.

Effects of BPA on right ventricular mechanical dysfunction in patients with inoperable CTEPH - A cardiac magnetic resonance study

PURPOSE

The aim of this study was to assess effects of balloon pulmonary angioplasty (BPA) on right ventricular (RV) mechanical dysfunction in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) via MRI.

METHOD

MRI at 1.5 Tesla and right heart catheterization were performed before and 6 months after BPA in 30 CTEPH patients (mean age 63.4 ± 10.6 years; 17 female). Feature-tracking strain analysis, including global longitudinal (GLS), circumferential (GCS), and radial (GRS) strain, was performed and compared with right ventricular function, myocardial remodelling (assessed by native T1 times), and pulmonary haemodynamics (mean pulmonary arterial pressure and pulmonary vascular resistance).

RESULTS

RVEF (35.9% to 48.4%) increased and mPAP (42.1 mmHg to 33.1 mmHg) and PVR (551.8 to 377.7 dyn∙s/cm⁵) decreased after BPA (all p < 0.0001). Moreover, RV strain increased (GLS -19.9 to -24.0%, p = 0.0003; GCS -9.4 to -11.0%, p = 0.0022; GRS 38.2 to 50.7%, p = 0.001) and septal native area-adjusted T1 time (AA-T1) decreased (1019.4 to 988.7 ms, p < 0.0001). GLS revealed the best correlations with RVEF (before BPA r = -0.75; after BPA r = -0.54), mPAP (r = 0.36; r = 0.52), PVR (r = 0.49; r = 0.48), and AA-T1 (r = 0.44; 0.19).

CONCLUSION

RV mechanical dysfunction, pulmonary haemodynamics, and myocardial remodelling are markedly improved by BPA. Moreover, RV strain values showed good correlations with RV function, pulmonary haemodynamics, and myocardial remodelling. Therefore, strain analysis might provide new insights regarding therapy outcome, monitoring, and prognosis.

Noninvasive prediction of pulmonary hemodynamics in chronic thromboembolic pulmonary hypertension by electrocardiogram-gated computed tomography

•

Easily measurable parameters from chest CT examinations enable prediction of pulmonary hemodynamics.

•

ECG-gated CTPA is superior to non-gated CT.

•

Non-invasive pH therapy monitoring or follow-up might be implemented in the future.

Purpose

The aim of the study was to investigate the potential of electrocardiogram (ECG)-gated computed tomography pulmonary angiography (CTPA) as a predictor of disease severity in patients with chronic thromboembolic pulmonary hypertension (CTEPH).

Method

Forty-five CTEPH patients with a mean age of 63.8 years±12.7 y (±standard deviation) who had undergone ECG-gated CTPA and right heart catheterization (RHC) were included in the study. Right ventricular to left ventricular volume ratio (RVV/LVV), diameter ratio on 4-chamber view (RVD4CH/LVD4CH), pulmonary trunk (PT) diameter, PT to aortic diameter ratio (PT/A), and septal angle were correlated to mean pulmonary artery pressure (mPAP). Moreover, RVV/LVV and RVD4CH/LVD4CH were adjusted to pulmonary diameter index (PADi) and PT/A index. Areas under the curve (AUC) for predicting mPAP above 40 mmHg, 35 mmHg, and 30 mmHg were calculated.

Results

RVD4CH/LVD4CH revealed the strongest correlation to mPAP before (r = 0.6507) and after (r = 0.7650; p < 0.0001) PT/A adjustment. The AUCs for predicting pH with mPAP over 40 mmHg and 30 mmHg were 0.9229 and 0.864, respectively. A cutoff value of 1.298 enabled prediction of pH with mPAP over 40 mmHg with a sensitivity, specificity, positive predictive, and negative predictive value of 80.00 %, 95.83 %, 88.46 %, and 94.12 %, respectively. Intra- and interobserver variability were excellent for all parameters.

Conclusion

Combining different and easily evaluable ECG-gated CTPA parameters enables excellent prediction of pulmonary hemodynamics in CTEPH patients. Ventricular diameter ratio on 4-chamber view adjusted by the PT/A ratio yielded the best correlation to mPAP.

Resonance vibration interventions in the femur: Experimental-numerical modelling approaches

MOTIVE

External vibration excitation might be key to many novel non-surgical interventions for pathologies in the musculoskeletal system and in other parts of the human organism. Lack of understanding about vibration patterns, their controllability, and reproducibility are three limitations of ongoing research. This study establishes a bovine vibration model and animal model replacements for future research.

METHODS

We used biological samples (n=5) and one polyurethane sample of the bovine femur. Mechanical resonance was measured experimentally and analysed numerically by finite element method.

MAIN RESULTS

The experiments obtained 5 distinct mode shapes for the biological sample set, with standard deviation < 7.5%. Finite element analysis of the biological samples can replicate experimental mode shape deflection. The use of polyurethane changes resonance character but results are also good approximations of the biological samples.

CONCLUSIONS

A model of the bovine femur with consistent resonance behaviour is presented with alternatives (polyurethane and finite element analysis) that can serve in reducing the number of necessary biological samples. Future work will be to adapt results to human anatomy. Of clinical interest will be to influence bone pathologies such as post-surgical non-union, or bone functionality as part of haematopoiesis and endocrine secretion.

Effect of synthetic bone replacement material of different size on shear stress resistance within impacted native and thermodisinfected cancellous bone: an in vitro femoral impaction bone grafting model

Antibiotic carrier particles of variable size might influence mechanic properties within impacted thermodisinfected and native cancellous bone different. Herafill®G containing calciumsulfate and calciumcarbonate provides high local concentrations of gentamicin being important for revision surgery in infected joint replacements. Native and thermodisinfected cancellous bone derived from 6 to 7 months old piglets was used for in vitro impaction bone grafting and supplemented each with Herafill®G granules of two different sizes. Micromovement of implants related to shear force was measured in 29 specimens distributed in 6 groups. Thermodisinfected cancellous bone revealed a significant higher shear force resistance than native bone with a mean difference of 423.8 mdeg/Nm (p < 0.001) ranging within 95% confidence interval from 181.5 to 666.0 mdeg/Nm. Adding small granules to thermodisinfected bone did not reduce shear force resistance significantly since adding large granules to native bone improved it by 344.0 mdeg/Nm (p < 0.003). Shear force resistance was found higher at the distal region of the implant compared to a proximal point of measurement throughout all specimens. Less impaction impulses were necessary for thermodisinfected bone. Thermodisinfected cancellous bone might achieve a higher degree of impaction compared with native bone resulting in increased resistance against shear force since impaction was found increased distally. Supplementation of thermodisinfected bone with small granules of Herafill®G might be considered for application of local antibiotics. Large granules appeared more beneficial for supplementation of native bone. Heterogeneity of bone graft and technical aspects of the impaction procedure have to be considered regarding the reproducibility of femoral impaction bone grafting.

Influence of antibiotic pellets on pore size and shear stress resistance of impacted native and thermodisinfected cancellous bone: An in vitro femoral impaction bone grafting model

Introduction

Morphology and mechanic properties of impacted cancellous bone are affected by carrier substances which provide high local concentrations of antibiotics.

Methods

Bone chips were taken from the femoral head of 6-7 months old piglets. One half was thermodisinfected and the other remained native. Ten specimens each were mixed with Herafill® antibiotic pellets and a control group of each 10 specimens respectively was examined. The cancellous bone was impacted according to Exeter technique and the implants were cemented. The distribution of the particles and the pores were defined with three dimensional computertomographic scan and shear force resistance was measured until failure.

Results

Shear force resistance was not measured significantly less for thermodisinfected (2.7 Nm) compared with native bone (3.5 Nm) and addition of antibiotic pellets reduced shear force resistance in both groups since this was significant for the native group. The average pore volume of the native bone specimens appeared significant smaller compared to the thermodisinfected group (p = 0.011) and the pore volume showed a negative correlation with shear force resistance (p = 0.044). Pore volume around the pellets was found significantly increased and it appeared smaller for native bone. The number of pellets located next to the implant showed a negative correlation with shear force resistance (p = 0.034) and the negative correlation increased for pellets below the tip of the shaft model (p = 0.024).

Conclusion

Adding antibiotic pellets to native and thermodisinfected impacted cancellous bone increased pore volume since the area around the pellets showed increased porosity which correlated with reduced shear force resistance. Computertomographic three dimensional measurement of porosity might predict shear force resistance of impacted cancellous bone and improve impaction of bone grafting intraoperatively.

[The new radiation protection legislation-part 1 : Modifications in radiology for the workflow in clinical routine]

BACKGROUND

On 31 December 2018, the new Radiation Protection Regulation came into effect in Germany and made the new Radiation Protection Act more concrete. The old Radiation Protection Regulation and X‑ray Regulation have thereby been replaced.

OBJECTIVES

The substantial modifications regarding the practical daily routine in radiology are summarized.

METHODS

Modifications and innovations of the New Radiation Protection Act and Regulation compared to the old Radiation Protection Regulation and X‑ray Regulation and accordances were evaluated. Thereby the main focus was in the relevance for workflow in clinical routine.

RESULTS AND CONCLUSION

The new legislation contains a number of regulations that provide crucial tools for implementation of radiation protection, quality assurance, and dose optimization. However, this also requires additional time and personnel.

Modification of chest radiography exposure parameters using a neonatal chest phantom

BACKGROUND

The acquisition of chest radiographs in neonates is of critical importance in diagnostics because of the risk of respiratory distress syndrome and pneumothorax in preterm infants.

OBJECTIVE

To achieve a dose reduction while preserving a diagnostic image quality for chest radiographs of neonates.

MATERIALS AND METHODS

All radiographs, generated on a fully digital X-ray unit by using a neonatal chest phantom, were evaluated under variation of the tube voltage (40-70 kV) and mAs levels (1-10.2 mAs) with and without an additional 0.1-mm copper (Cu) filtration. Noise, contrast and contrast-to-noise ratio for bronchus, heart, lungs and vessels were determined. Visual assessment of the image quality was carried out by three radiologists using a Likert scale. To evaluate a maximally possible dose reduction, the dose of the radiographs with still acceptable image quality at a minimal dose was compared to the dose of the radiographs with the standard settings used in clinical routine.

RESULTS

The noise showed decreasing values with increasing dose, while the contrast values were increased. For the contrast-to-noise ratio, a digressive course of the values as a function of the tube voltage was found. The visual evaluation of image quality showed the best evaluation of the structures at the lowest possible dose in the settings (44 kV, 3.36 mAs) with copper filtration and in the settings (44 kV, 1.56 mAs) without copper filtration. A maximum dose reduction from 8.29 μSv to 2.21 μSv (about 73%) was obtained.

CONCLUSION

A dose reduction while preserving diagnostic image quality in a digital X-ray system is generally possible by reducing the tube voltage and simultaneous adaptation of the mAs settings.

[Mesenchymal abdominal tumors in children]

Mesenchymal tumors in childhood comprise benign and malign entities and differ regarding typical sites of manifestation, age peak and clinical symptoms. In some cases biopsy is mandatory. If nephroblastoma is a possible diagnosis, biopsy must be avoided by all means in order to avoid biopsy tract metastasis. Imaging is used to narrow the differential diagnosis, describe the exact extent of the lesion and deliver complete staging. In pediatric patients sonography and MRI are the most important imaging modalities. Low-dose CT of the thorax serves for assessment of possible pulmonary metastases.

Low testosterone in ApoE/LDL receptor double-knockout mice is associated with rarefied testicular capillaries together with fewer and smaller Leydig cells

The testis as a site for atherosclerotic changes has so far attracted little attention. We used the apolipoprotein E (ApoE)/low density lipoprotein (LDL) receptor deficient mouse model (KO) for atherosclerosis (20, 40, 60 and 87-week-old) to investigate whether Leydig cells or the capillary network are responsible for reduced serum testosterone levels previously observed in extreme ages of this model. In KO mice, overall testosterone levels were reduced whereas the adrenal gland-specific corticosterone was increased excluding a general defect of steroid hormone production. In addition to micro-CT investigations for bigger vessels, stereology revealed a reduction of capillary length, volume and surface area suggesting capillary rarefaction as a factor for diminished testosterone. Stereological analyses of interstitial cells demonstrated significantly reduced Leydig cell numbers and size. These structural changes in the testis occurred on an inflammatory background revealed by qPCR. Reduced litter size of the KO mice suggests hypo- or infertility as a consequence of the testicular defects. Our data suggest reduced testosterone levels in this atherosclerosis model might be explained by both, rarefication of the capillary network and reduced Leydig cell number and size. Thus, this study calls for specific treatment of male infertility induced by microvascular damage through hypercholesterolemia and atherosclerosis.

Multimodality imaging evaluation before transcatheter aortic valve implantation: incidence of contrast medium-induced acute kidney injury, risk factors and prognosis

AIM

To evaluate the incidence, risk factors, and prognostic implications of contrast medium-induced acute kidney injury (CI-AKI) in patients undergoing transcatheter aortic valve implantation (TAVI) evaluation.

MATERIALS AND METHODS

Datasets from 98 out of 207 consecutive patients referred for multidetector computed tomography (MDCT) for TAVI evaluation were eligible for evaluation and were analysed retrospectively. The incidence of CI-AKI was correlated to outcome and to potential risk factors: kidney function (estimated glomerular filtration rate [eGFR]), heart failure, diabetes, amount of contrast medium, and duration of examination period.

RESULTS

CI-AKI occurred in 67 patients (68.4%) and mainly correlated with eGFR (p=0.01) and the amount of contrast medium as a function of eGFR (p=0.04). CI-AKI occurred before TAVI in 36 (53.7%) patients of which 13 (19.4%) did not undergo TAVI. In-hospital all-cause mortality was 21.4%, and of those 21 patients, 18 (85.7%) had CI-AKI and nine (42.9%) did not undergo TAVI. One-year all-cause mortality was 39.8%, and of those 39 patients who died within 1 year, 31 (79.5%) had CI-AKI.

CONCLUSION

CI-AKI mostly occurs already before TAVI as a consequence of pre-procedural imaging, which therefore represents the main contributor for CI-AKI in relation to TAVI. Regarding the observation that some patients will ultimately have no benefit because TAVI is not performed and the poor prognosis linked to CI-AKI should encourage improvement in patient selection when referring to pre-procedural imaging.

Lung cancer–associated pulmonary hypertension: Role of microenvironmental inflammation based on tumor cell–immune cell cross-talk

Lung cancer–associated pulmonary hypertension is associated with microenvironmental inflammation caused by tumor cell–immune cell cross-talk.

[Diseases of connective tissue in IgG4-associated autoimmune diseases]

The IgG4-associated diseases of connective tissue are caused by allergen-mediated autoimmune processes. The retroperitoneum, mesentery and mediastinum as well as other less common localizations, such as the neck, orbit and periarticular connective tissue can be affected. Inflammatory fibrosis is initially dominated by a lymphocytic and plasma cell-rich infiltrate and later by cell-poor storiform fibrosis. Stenosis and occlusion of vessels, ureters and intestines can cause severe complications. Computed tomography (CT) and magnetic resonance imaging (MRI) can be implemented in the diagnostic algorithm to narrow the differential diagnosis, delineate the distribution of fibrosis and reveal complications.

White Paper: Interventional MRI: Current Status and Potential for Development Considering Economic Perspectives, Part 2: Liver and Other Applications in Oncology

Background MRI is attractive for guiding and monitoring interventional procedures due to its high intrinsic soft tissue contrast and the possibility to measure flow and cardiac function. Methods Technical solutions have been developed for all procedural steps including imaging guidance, MR-safe catheters and instruments and patient monitoring. This has led to widening of the clinical applications. Interventional MRI is becoming increasingly important for the treatment of patients suffering from malignant diseases. The detectability of masses and consequently their accessibility for biopsy is higher, compared to other modalities, due to the high intrinsic soft tissue contrast of MRI. Temperature-dependent sequences allow for minimally invasive and tissue-sparing ablation (A-0 ablation). Conclusion Interventional MRI has become established in the clinical routine for a variety of indications, including biopsies and tumor ablation. Since the economic requirement of covering costs by reimbursement is met and interventional MRI decreases the mortality and morbidity of interventional procedures, broader application of interventional MRI can be expected in the clinical routine in the future. Key points  · Particularly for the treatment of oncological patients, interventional MRI is superior to other methods with respect to minimal invasiveness and tissue protection due to the ability to exactly determine tumor borders and to visualize and control the size of the ablation area on the basis of MR temperature measurement.. · Due to the better visualization of targets and the effects of ablation in tissue, interventional MRI can lower the mortality and morbidity associated with these interventions for many indications.. · The complex comparison of costs and reimbursement shows that this application can be performed in a cost-covering manner and broader application can be expected in the future.. Citation Format · Barkhausen J, Kahn T, Krombach GA et al. White Paper: Interventional MRI: Current Status and Potential for Development Considering Economic Perspectives, Part 2: Liver and Other Applications in Oncology. Fortschr Röntgenstr 2017; 189: 1047 - 1054.

Balloon pulmonary angioplasty for inoperable patients with chronic thromboembolic pulmonary hypertension: the initial German experience

Balloon pulmonary angioplasty (BPA) is an emerging treatment for patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH).We report on a prospective series of 56 consecutive patients who underwent 266 BPA interventions (median, five per patient) at two German institutions. All patients underwent a comprehensive diagnostic work-up including right heart catheterisation at baseline and 24 weeks after their last intervention.BPA resulted in improvements in WHO functional class, 6 min walk distance (mean change, +33 m), right ventricular function and haemodynamics, including a decline in mean pulmonary artery pressure by 18% and in pulmonary vascular resistance by 26%. Procedure-related adverse events occurred in 9.4% of the interventions. The most common complications were related to pulmonary vascular injury and consecutive pulmonary bleeding. Most of these events were asymptomatic and self-limiting, but one patient died from pulmonary bleeding, resulting in a mortality rate of 1.8%.BPA resulted in haemodynamic and clinical improvements but was also associated with a considerable number of complications, including one fatal pulmonary bleeding. As the effects of BPA on survival are unknown, randomised controlled outcome trials comparing BPA with approved medical therapies in patients with inoperable CTEPH are required to allow for appropriate risk-benefit assessments.

Quantitative and qualitative assessment of left ventricular volume with ECG-gated multislice spiral CT: value of different image reconstruction algorithms in comparison to MRI

Purpose: To assess the value of different image reconstruction algorithms for assessment of the left ventricular function using retrospectively ECG-gated multislice spiral computed tomography (MSCT) of the heart.

Material and Methods: MSCT and cine magnetic resonance (MR) imaging of the heart were performed in 15 patients. For MSCT, standard and multisegmental image reconstruction with improved temporal resolution were used. Standardized multiplanar reformats in the short axis and long axis views were reconstructed from MSCT data. End-systolic (ESV) and end-diastolic volume (EDV), stroke volume (SV), ejection fraction (EF) and myocardial mass (MM) were calculated. Left ventricular wall motion was assessed qualitatively.

Results: MSCT was in acceptable agreement with MR imaging for quantification of the ventricular function. According to the Bland–Altman approach the mean differences for the left ventricular volumes (ESV, EDV, SV) ranged from −9.6 ml to 3.1 ml with standard image reconstruction and from −0.6 ml to 1.9 ml utilizing multisegmental image reconstruction with limits of agreement ranging from −26.6 ml to 12.5 ml and −15.6 ml to 15.0 ml, respectively. Applying the multisegmental image reconstruction algorithm, a significantly improved agreement with the MR data was found for EDV, SV and EF. For wall motion analysis, standard image reconstruction showed a significant difference to MR imaging with a correspondence in 83.75% of the 240 assessed segments, while multisegmental image reconstruction agreed with MR imaging in 92.5% of the segments.

Conclusion: Multisegmental image reconstruction improves the quantitative assessment of left ventricular function when compared to standard image reconstruction. Multisegmental image reconstruction allows qualitative wall motion analysis.

Sonothrombolysis with BR38 Microbubbles Improves Microvascular Patency in a Rat Model of Stroke

Background

Early recanalization of large cerebral vessels in ischemic stroke is associated with improved clinical outcome, however persisting hypoperfusion leads to poor clinical recovery despite large vessel recanalization. Limited experimental sonothrombolysis studies have shown that addition of microbubbles during treatment can improve microvascular patency. We aimed to determine the effect of two different microbubble formulations on microvascular patency in a rat stroke model.

Methods

We tested BR38 and SonoVue® microbubble-enhanced sonothrombolysis in Wistar rats submitted to 90-minute filament occlusion of the middle cerebral artery. Rats were randomized to treatment (n = 6/group): control, rt-PA, or rt-PA+3-MHz ultrasound insonation with BR38 or SonoVue® at full or 1/3 dose. Treatment duration was 60 minutes, beginning after withdrawal of the filament, and sacrifice was immediately after treatment. Vascular volumes were evaluated with microcomputed tomography.

Results

Total vascular volume of the ipsilateral hemisphere was reduced in control and rt-PA groups (p<0.05), but was not significantly different from the contralateral hemisphere in all microbubble-treated groups (p>0.1).

Conclusions

Microbubble-enhanced sonothrombolysis improves microvascular patency. This effect is not dose- or microbubble formulation-dependent suggesting a class effect of microbubbles promoting microvascular reopening. This study demonstrates that microbubble-enhanced sonothrombolysis may be a therapeutic strategy for patients with persistent hypoperfusion of the ischemic territory.

Development and Suggestion of a Cardiac CTA Scoring System for the Prediction of Revascularization Success in Chronic Total Occlusions (CTO) of the Coronary Arteries

OBJECTIVE

Analyzing occluded segments with computed tomography angiography (CTA) prior to percutaneous coronary intervention (PCI) increased revascularization success in chronic total occlusions (CTO). The aim of our study was to develop a scoring system for the prediction of PCI success in CTO.

MATERIALS AND METHODS

41 consecutive CTO patients (30 male; 63.1 years +/- 8.3 standard deviation) underwent CTA prior to PCI. All CTOs were categorized by two radiologists in consensus regarding the presence of special features and without knowledge of PCI outcome. All outcome criteria were evaluated. Afterwards one point was assigned for each unequally distributed outcome criteria per CTO and all points were added up to a single score.

RESULTS

Severe calcifications (failure group 68.8 % vs. success group 28.0 %; p < 0.02) and intraluminal calcifications (68.8 %; 40.0 %), tortuosity (25.0 %; 0 %; p < 0.02), linear intrathrombus enhancement (37.5 %; 60.0 %) and distal vessel disease (68.8 %; 44.0 %) were unequally distributed. By adopting a threshold of 4 points or higher (maximum 5 points), the results were: sensitivity 31.3 %, specificity 100 %, negative predictive value (NPV) 69.4 % and positive predictive value (PPV) 100 %. The PCI complication rate was 9.8 % and the mean contrast media amount was 234.4 ml.

CONCLUSION

With the suggested scoring system, based on five CTA criteria, PCI failure could be predicted with high PPV and specificity in our group of patients, but the NPV and sensitivity are low. However, 5 unsuccessful PCIs (13.2 %) could have been avoided and none would have been wrongly omitted. Regarding the complication rate during PCI and the high amounts of contrast media needed, a prediction system appears to be desirable and should be the object of large-scale trials.

KEY POINTS

Single predictors of revascularization success in CTO have been identified. Success rates are improved by analyzing CTA data sets prior to revascularization approaches. Prediction of revascularization success via a scoring system based on five CTA criteria seems promising. Patient selection for the right treatment options might be improved in the future due to application of the scoring system. Also risks, complications, contrast media amounts and radiation doses might be reduced.

[Pulmonary embolism]

Pulmonary embolism is a potentially fatal disorder and frequently seen in critical care and emergency medicine. Due to a high mortality rate within the first few hours, the accurate initiation of rational diagnostic pathways in patients with suspected pulmonary embolism and timely consecutive treatment is essential. In this review, the current European guidelines on the diagnosis and therapy of acute pulmonary embolism are presented. Special focus is put on a structured patient management based on the individual risk of early mortality. In particular risk assessment and new risk-adjusted treatment recommendations are presented and discussed in this article.

The impact of early surgical intervention in free intestinal perforation: a time-to-intervention pilot study

PURPOSES

An abdominal inflammatory focus is the second most often source of sepsis with a high risk of death in surgical intensive care units. By establishing evidence-based bundled strategies the surviving sepsis campaign provided an optimized rapid and continuous treatment of these emergency patients. Hereby the hospital mortality decreased from 35 to 30 %. Sepsis treatment is based on three major therapeutic elements: surgical treatment (source control), antiinfective treatment, and supportive care. The international guidelines of the surviving sepsis campaign were updated recently and recommend rapid diagnosis of the infection and source control within the first 12 h after the diagnosis (grade 1c). Interestingly this recommendation is mainly based on studies on soft tissue infections.

METHODS

In this retrospective analysis 76 septic patients with an intraabdominal inflammatory focus were included. All patients underwent surgery at different time-points after diagnosis.

RESULTS

With 80 % patients of the early intervention group had an improved overall survival (vs. 73 % in the late intervention group).

CONCLUSIONS

Literature on the time dependency of early source control is rare and in part contradicting. Results of this pilot study reveal that immediate surgical intervention might be of advantage for septic emergency patients. Further multi-center approaches will be necessary to evaluate, whether the TTI has any impact on the outcome of septic patients with intestinal perforation.

Neovascularization of osteoporotic metaphyseal bone defects: A morphometric micro-CT study

PURPOSE

Neovascularization is essential for bone regeneration in fractures. This study aimed to investigate the microvascular morphology and distribution in the non-injured femur and the neovascularization of the metaphyseal critical size defect in a small animal model of osteoporosis.

MATERIALS AND METHODS

Female rats (n=7) were ovariectomized (OVX) and received a multideficiency diet. Three months after OVX, a 5mm wedge shaped critical size defect was cut at the distal femoral metaphysis and stabilized with a T-shaped mini-plate. After six weeks, the animals were euthanized, and femora were removed and decalcified for micro-CT measurement of fracture neovascularization.

RESULTS

No fracture healing was observed along the critical size defects. In the non-injured bone, micro-vessel distribution showed a specific pattern, thereby enabling a differentiation between epi-, meta- and diaphysis. Micro-CT based morphometry revealed a significant reduction of the vascular volume fraction as well as the vascular thickness (p<0.001) in the critical size defect compared to the intact contralateral femur. Blood volume related vascular surface (vascular surface/volume) increased significantly (p<0.001). Connectivity density and tissue volume related vascular surface (vascular surface density) did not change significantly.

CONCLUSIONS

Micro-CT based vascular morphometry demonstrated differences between epi-, meta- and diaphysis in the non-injured bone as well as differences between the critical size defect and the non-injured metaphysis. As angiogenesis is a crucial prerequisite that precedes osteogenesis, our results may influence further evaluation of osteoconductive or osteogenic biomaterials in this small animal model of osteoporosis.

Changes in Dynamic Pelvic Floor Magnet Resonance Imaging and Patient Satisfaction after Resection Rectopexy for Obstructed Defecation Syndrome

PURPOSE

Resection rectopexy (RR) provides good functional results and low recurrence rates for the treatment of obstructed defecation syndrome based on rectal prolapse and cul-de-sac syndrome, whereas little is known about changes in pelvic floor dynamics and patient satisfaction after surgery.

MATERIALS AND METHODS

Within three years 26 consecutive female patients were prospectively included. Indications for RR (22 laparoscopic, 3 primary open and 1 converted-to-open) were rectal prolapse III° in 11 patients and cul-de-sac syndrome in 15 patients. Patients' quality of life (QOL), fecal behavior and defecation-associated pain were investigated before and after surgical treatment using anamnesis and clinical examination, Rand 36-idem health survey (SF-36), Cleveland-Clinic Incontinence Score (CCIS) and the visual analog scale for defecation-associated pain (VAS). Dynamic pelvic floor magnet resonance imaging (dPF-MRI) was used for the investigation of changes in pelvic floor anatomy and function before and after surgery.

RESULTS

RR improved the rate of fecal incontinence (p < 0.01) and CCIS (p = 0.01). The use of laxatives (p = 0.01), the need for self-digitation (p = 0.02) and VAS (p < 0.01) were decreased, leading to improvements in QOL (overall p < 0.01). RR led to shortening of the H-line but not of the M-line under rest (p < 0.01) and during defecation (p = 0.04). A rectocele was co-incident in all patients in dPF-MRI before surgery. RR led to a reduction (p < 0.01) and declined protrusion (p = 0.03) of the rectocele. This results in a decreased rate of cul-de-sac (p < 0.01) and increased rate of complete defecation (p < 0.01) after surgery. At the 36-month follow-up no recurrence was observed.

CONCLUSION

RR promises high rates of patient satisfaction and improvement in pelvic floor anatomy in select patients.

KEY POINTS

• RR improves the pelvic floor anatomy of patients suffering from ODS. • RR improves the QOL of patients suffering from ODS. • An improvement in pelvic floor anatomy led to an improved QOL. • RR is an adequate treatment for select patients suffering from ODS.

T1, T2 Mapping and Extracellular Volume Fraction (ECV): Application, Value and Further Perspectives in Myocardial Inflammation and Cardiomyopathies

Cardiac magnetic resonance imaging (CMRI) is a versatile diagnostic tool. One of its main advantages is the possibility of tissue characterization. T1-weighted images for scar and T2-weighted images for edema visualization are key methods for tissue characterization. Otherwise these sequences are strongly limited for the detection of diffuse myocardial pathologies. Recently, rapid technical innovations have generated new techniques. T1, T2 mapping and evaluation of the extracellular volume fraction (ECV) allow quantification of diffuse myocardial pathologies and showed great potential in the visualization of fibrosis, edema, amyloid, iron overload and lipid. In the future these techniques might enable the detection of early cardiac involvement, even act as a prognosticator. Moreover, therapy monitoring and follow-up might be possible due to versatile parameter quantification with these new techniques.

KEY POINTS

CMR allows for tissue characterization via T1- and T2-weighted sequences. In cases of diffuse, global myocardial pathologies, correct image interpretation with traditional CMR sequences might be difficult. T1, T2 mapping and ECV can quantify diffuse, global myocardial pathologies. Alterations of myocardial T1 and T2 relaxation times occur in various myocardial diseases (e.g. acute myocarditis). In the future mapping might act as a prognosticator or therapy monitoring tool.

[Health technology assessment (HTA). Developments in healthcare and potential for radiology]

CLINICAL/METHODICAL ISSUE

Cost-intensive measures and procedures, such as also employed in radiology, have far-reaching economic implications in respect to increasing expenditure with limited resources.

STANDARD RADIOLOGICAL METHODS

Health technology assessment (HTA) describes the systematic evaluation of medical procedures and technologies which in recent years has been introduced by many countries into healthcare politics.

ASSESSMENT

In many cases HTA analyses can be directly implemented into practice as shown by the examples given in this article; however, in the current form of HTA the practical implementation for radiology often presents the problem that the cost-benefit ratio does not yet have a comprehensive view in the HTA report but is limited to a subsection, e.g. current costs versus sensitivity of a method. Since its inception radiology has had a high power of innovation and new developments will also substantially determine the future years. These procedures must not only be evaluated with respect to feasibility but also in the sense of the HTA in the total concept.

PRACTICAL RECOMMENDATIONS

In radiology there are also a large number of possibilities for radiologists not only as passive consumers of HTA reports but also to become active participants in this process, an opportunity which should be taken advantage of.

Right ventricular adaptation to pulmonary pressure load in patients with chronic thromboembolic pulmonary hypertension before and after successful pulmonary endarterectomy--a cardiovascular magnetic resonance study

BACKGROUND

The aim of the study was to characterize RV adaptation to varying loading conditions in patients with chronic thromboembolic hypertension (CTEPH) before and after pulmonary endarterectomy (PEA). Nearly 4% of patients with pulmonary embolism develop CTEPH. PEA offers a cure with excellent outcome. By use of cardiovascular magnetic resonance (CMR) combined with hemodynamic measurements pulmonary arterial elastance (Ea-pulm_i), end-systolic right ventricular elastance (Ees-RV_i) and ventriculo-arterial coupling (Ea-pulm_i/Ees-RV_i) can be studied before and after PEA.

METHODS

Sixty-five patients (mean age 41±12 years, 28 female) underwent CMR pre- and post-PEA. Ejection fraction (EF), end-diastolic (EDVi), end-systolic (ESVi), and stroke (SVi) volumes were indexed for body surface area. Ea-pulm_i was calculated as pulmonary artery mean pressure (mPAP)/SVi, and Ees-RV_i as mPAP/ESVi.

RESULTS

mPAP decreased from 47±12 to 25±9 mmHg, p=0.0001. Ea-pulm_i was increased before PEA and normalized afterwards (2.8±2.1 vs. 0.85±0.4 mmHg/ml/m2, p=0.0001). Ees-RV_i was depressed before and after PEA (0.72±0.27 vs. 0.66±0.3 mmHg/ml/m2, p=0.13). EF improved from 25±12% to 46±10%, p=0.0001, because ventriculo-arterial coupling was restored (4.2±3 vs. 1.4±0.6, p=0.0001). EDVi and ESVi mproved significantly (EDVi 92±32 to 72±23 ml, p=0.0001; ESVi 69±31 to 41±18 ml, p=0.0001).

CONCLUSION

RV function is largely determined by afterload and returns to normal once afterload is normalized. This is paralleled by a significant improvement of CMR indices of right ventricular remodelling.

[Acute pancreatitis]

Bei der akuten Pankreatitis handelt es sich um eine potenziell tödlich verlaufende Erkrankung mit individuell unterschiedlich ausgeprägter systemischer Beteiligung. Aus diesem Grund kommen der frühzeitigen Diagnose und nachfolgenden Risikostratifikation im klinischen Management dieser häufigen gastroenterologischen Erkrankung entscheidende Rollen zu. Schwere Verlaufsformen treten in etwa 20 % der Fälle auf und bedürfen zumeist intensivmedizinischer Überwachung und interdisziplinärer Behandlung. Therapeutisch stehen in der Akutphase die adäquate Flüssigkeitssubstitution und suffiziente Schmerztherapie im Vordergrund. Im Hinblick auf den Einsatz von Antibiotika und die Anpassung der Ernährung hat sich in den letzten Jahren ein Paradigmenwechsel vollzogen. Je nach Schwere der Erkrankung und möglichen Komplikationen können auch endoskopisch-/radiologisch-interventionelle Maßnahmen oder eine operative Versorgung notwendig werden.

Western diet in ApoE-LDLR double-deficient mouse model of atherosclerosis leads to hepatic steatosis, fibrosis, and tumorigenesis

Nonalcoholic fatty liver disease has been linked to cardiovascular diseases and atherosclerosis. The aim of the current study was to characterize the hepatic pathology leading to fibrosis and tumors in a murine model of atherosclerosis. Male apolipoprotein E/low-density lipoprotein receptor double-knockout mice (AL) mice were fed with a high fat and high cholesterol western diet for 35 weeks (AL mice on WD). Protein and mRNA analysis as well as micro-computed tomography (micro-CT) were performed to assess oxidative stress, liver damage, inflammation, fibrosis, signaling pathways, vascularization, and tumorigenesis. Controls were chosen to distinguish between genetically and dietary effects in steatohepatitis and associated tumorigenesis. Hepatic inflammation and dyslipidemia were increased in AL mice on WD compared with wild-type mice on WD. Uniquely, AL mice on WD showed a spontaneous development of tumors (30% of cases) and thickening of intrahepatic vessel walls. Functionally relevant underlying signaling pathways such as NF-κB, Stat3, JNK, and AKT were differentially regulated between AL and wild-type mice on WD. Micro-CT was capable of visualizing and quantitatively distinguishing tumor neovascularization from vascularization in non-neoplastic liver tissue. AL mice on WD diet represent a novel model combining atherosclerosis and nonalcoholic fatty liver disease. Signaling pathways of liver cell damage and compensatory liver regeneration in combination with enhanced inflammation appear to be crucial for the spontaneous development of tumors in AL mice on WD. Micro-CT represents a new and powerful technique for the ultrastructural and three-dimensional assessment of the vascular architecture of liver tumors.