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Endovascular embolization using liquid embolic agents is a safe and effective treatment option for AVMs and fistulas. Because reliable visibility of these liquid embolic agents is essential for intraprocedural visual control to prevent complications, novel angiographic systems are equipped with material-specific roadmap modes. The aim of this study was the systematic in vitro comparison of conventional and material-specific roadmap modes regarding the visibility of the most used liquid embolic agents.A recently introduced in vitro model, resembling cerebral vessels, was embolized with Onyx 18, Squid 18, PHIL 25%, andSignificant differences between conventional and material-specific roadmap modes regarding the visibility of the liquid embolic agents were observed for all study groups. All liquid embolic agents were better visible in the material-specific roadmap modes compared with the conventional mode in qualitative and quantitative analyses (eg, Onyx in conventional-versus-material-specific modes along the 1.0-mm sector: mean contrast-to-noise ratio, 5.69 [SD, 0.85] versus 47.18 [SD, 5.72];In this in vitro study, we demonstrated a better visibility of all investigated liquid embolic agents by using material-specific roadmap modes compared with the conventional roadmap technique. Especially in complex anatomic situations, these novel roadmap modes could improve the visual control and thus the safety and efficacy of embolization procedures in clinical practice.

Imaging of the postoperative shoulder joint includes complex, diagnostically challenging changes regarding the anatomical structures.Case-based presentation of common surgical procedures, expected postoperative findings, and typical complications.Interdisciplinary evaluation of (didactically instructive) cases and discussion of pertinent literature and expert opinions.Presentation of normal postoperative findings and complications after subacromial decompression, surgical treatment of rotator cuff lesions, SLAP (superior labral anterior to posterior) lesions/lesions of the long biceps tendon, Bankart lesions as well as instability-related procedures and after shoulder arthroplasty. Discussion of the appropriate use of imaging methods with a focus on magnetic resonance imaging (MRI), which are supplemented by computed tomography (CT), and conventional x‑ray images.The broad spectrum of complex findings as well as the evermore developing and thereby changing surgical procedures result in significant challenges in the radiological evaluation of the postoperative shoulder joint. To differentiate physiological reactions from pathological changes it is necessary to have general knowledge of the common surgical procedures, expected postoperative findings and possible complications. A variety imaging modalities can be used to further advance diagnostic precision.HINTERGRUND: Die radiologische Bildgebung des postoperativen Schultergelenks umfasst teils komplexe, diagnostisch anspruchsvolle Veränderungen der anatomischen Strukturen.Fallbasierte Darstellung der gängigen Schulteroperationen, der zu erwartenden radiologischen Veränderungen sowie der klassischen Komplikationen.Interdisziplinäre Auswertung und Aufarbeitung didaktisch wertvoller Patientenfälle sowie Diskussion von Grundlagenarbeiten und Expertenempfehlungen.Darstellung der wichtigsten postoperativen Veränderungen und Komplikationen nach subakromialer Dekompression, operativer Therapie von Rotatorenmanschettenläsionen, SLAP-Läsionen („superior labral tear from anterior to posterior“), Läsionen der langen Bizepssehne, Bankart-Läsionen sowie instabilitätsbezogenen Eingriffen und nach Schulterarthroplastik. Diskussion des Einsatzes bildgebender Verfahren mit Fokus auf der Magnetresonanztomographie (MRT), ergänzt durch eine Computertomographie (CT) und konventionelle Röntgenaufnahmen.Das breite Spektrum teils komplexer, bildmorphologischer Befunde in Kombination mit sich stetig weiterentwickelnden Operationsverfahren macht die radiologische Diagnostik des postoperativen Schultergelenks zu einer anspruchsvollen Aufgabe. Die Kenntnis der chirurgischen Verfahren, der zu erwartenden postoperativen Befunde sowie der möglichen Komplikationen ist essenziell, um physiologische Reaktionen von pathologischen Veränderungen differenzieren zu können. Verschiedenste Modalitäten können hierbei ergänzend eingesetzt werden.

Mit der Computertomographie (CT) konnen Thromben im linken Vorhofohr (LAA) dargestellt werden. Es wurde untersucht, ob sich die diagnostische Genauigkeit durch die Dual-Energy-Technik im Vergleich zur transosophagealen Echokardiographie (TEE) verbessert. Weiterhin wurde der Einfluss von Protokollparametern auf die Strahlendosis quantifiziert. Die TEE-Patienten wurden den verschiedenen CT-Protokollen zugeordnet. Alle CTs wurden auf das Vorhandensein von LAA-Thromben und Dual-Energy-CT-Scans sowie zusatzlich quantitativ auf die Jodkonzentration analysiert. Die TEE wurde qualitativ auf das Vorhandensein von Thromben untersucht. Von Insgesamt 32 eingeschlossenen Patienten hatten 6 einen mittels TTE diagnostizierten Thrombus. Die qualitative CT-Beurteilung ergab eine Sensitivitat von 83 % und eine Spezifitat von 88 % fur die LAA-Thrombus-Detektion. Bei 26 Patienten wurde eine Dual-Energy-CT durchgefuhrt. Die mittlere Jodkonzentration betrug 8,6 mg/cm3 und war bei Patienten mit LAA-Thromben signifikant niedriger als bei Patienten ohne LAA-Thromben. Ferner ergab sich ein inkrementeller Wert fur die Erkennung von LAA-Thromben (AUC: 0,950 vs. 0,867 bei kombinierter vs. nur qualitativer Beurteilung; p = 0,04). Die mediane Strahlendosis betrug 1,83 mSv. Unabhangig voneinander war die Dosis bei Beschrankung des Scanabschnitts auf den LAA und beim prospektiven Gating niedriger, wahrend Arrhythmie und Dual-Energy-Technik die Strahlendosis nicht beeinflussten. Die CT bietet eine gute diagnostische Genauigkeit fur den Nachweis von LAA-Thromben, die durch Joddichtemessung mittels Dual-Energy-CT noch weiter verbessert werden kann. Mit einem optimierten Protokoll kann eine angemessen niedrige Strahlendosis erreicht werden.

Background To demonstrate the efficacy of percutaneous computed tomography (CT)-guided afferent lymphatic vessel sclerotherapy (ALVS) in the treatment of postoperative lymphatic leakage (LL) after ineffective therapeutic transpedal lymphangiography (TL). Methods A retrospective review in this institute involving 201 patients was conducted from May 2011 to September 2018. Patients diagnosed with postoperative LL undergoing ineffective therapeutical TL before the performance of percutaneous CT-guided ALVS were involved. Technical success and clinical success of TL and ALVS were established. The technical success and efficacy of ALVS in the treatment of postoperative LL after ineffective therapeutic TL were assessed. The clinical success rate of ALVS is also assessed, and the complications are reviewed. Results In total, nine patients were involved including three patients (33.3%) presented with chylothorax, three patients (33.3%) presented with inguinal lymphatic fistula/lymphocele, and three patients (33.3%) presented with lymphatic fistula in the thigh; 27 ± 18 days (mean ± standard deviation) after surgery, therapeutic TL was successfully performed and showed definite afferent lymphatic vessel and leakage site in all the patients. Due to clinical failure after TLs, the following ALVS was performed with a mean interval of 12 ± 8 days after TL. The technical success rate was 9/9 (100.0%, 95% confidence interval [CI] 63.1–100.0%). An average of 2.7 ± 1.3 mL 95% ethanol as sclerosant agent was injected during the procedure. The clinical success was observed in 8 of the 9 patients (88.9%, 95% CI 51.8–99.7%) with a time between ALVS and the LL cure of 8 ± 6 days. No complications were reported. Conclusions Our results showed the role of percutaneous CT-guided ALVS as a safe, feasible, and effective salvage treatment for postoperative LL after ineffective TL.

Hintergrund Klinisch ist COVID-19 (Corona Virus Disease 2019) mit einem breiten Spektrum an Symptomen verbunden, das von milden Beschwerden eines oberen Atemwegsinfekts bis zur lebensbedrohlichen hypoxischen respiratorischen Insuffizienz und Multiorganversagen reichen kann. Fragestellung Zu den initial identifizierten pulmonalen Schädigungsmustern, wie dem diffusen Alveolarschaden bei akutem Lungenversagen, gesellen sich neue Erkenntnisse, die ein komplexeres Szenario zeichnen. Hierzu gehören Mikrogefäßbeteiligungen und ein breites Spektrum assoziierter Pathologien multipler Organsysteme. Eine Rückskalierung mikrostruktureller Gefäßveränderungen ist durch gezielte Korrelation pathologischer Obduktionsergebnisse mit radiologischer Bildgebung möglich. Material und Methoden Radiologisch-pathologische Korrelation und mikroradiologische Bildgebung zur Untersuchung der Mikrogefäßbeteiligung bei letaler COVID-19. Ergebnisse Die Fälle zweier COVID-19-Patienten werden präsentiert. Patient 1 zeigte eine relative Minderperfusion in Lungenarealen, die radiologisch keine COVID-19-typischen Infiltrate aufwiesen; die gezielte autoptische Korrelation ergab auch in diesen Lungenabschnitten bereits subtile Zeichen eines Mikrogefäßschadens. Patient 2 zeigte radiologisch und pathologisch eine fortgeschrittene COVID-19-typische Lungenstrukturdestruktion; der Fall illustriert die Schädigungsmuster der Blut-Luft-Schranke. Die CT-morphologisch perfusionsgestörte Darmwand von Patient 2 konnte letztendlich mikroskopisch nicht eindeutig auf einen intestinalen Mikrogefäßschäden zurückgeführt werden. Schlussfolgerung Die Ergebnisse weisen neben der Mikrogefäßthrombosierung auf eine funktionelle pulmonale Vasodysregulation im Rahmen der vaskulären Phase von COVID-19 hin. Hervorzuheben sind die klinische Relevanz von Obduktionen und eine enge Verzahnung von radiologischen Bildbefunden mit histopathologischen Schädigungsmustern zum besseren Verständnis von COVID-19.

Die Schwere des Verlaufs und die Sterblichkeit der Mukoviszidose (zystische Fibrose, CF) ist wesentlich durch die pulmonale Manifestation gepragt. Eine fruhe Diagnose und rasch einsetzende Therapie sind entscheidend fur einen langfristigen Erhalt der Lungenfunktion. Rontgen-Thorax und Computertomographie (CT) stehen bei der Diagnostik im Vordergrund, um den Krankheitsverlauf und das Verteilungsmuster erkennen zu konnen. Zur Vermeidung von Folgeschaden aufgrund ionisierender Strahlung durch Rontgen und CT ist das Interesse an der Magnetresonanztomographie (MRT) in der vergangenen Dekade gewachsen. Wesentliche Befunde sind Bronchialwandveranderungen, Bronchiektasen und „mucus plugging“, welche bis zu 60 % bei Kindern im Vorschulalter gefunden werden. Pleuraveranderungen und Konsolidierungen treten gehauft bei pulmonalen Exazerbationen auf. An funktionellen Veranderungen zeigen junge CF-Patienten haufig ein Mosaikmuster, und bereits ab Geburt konnen Perfusionsstorungen unterschiedlicher und im Verlauf wechselnder Schwere in 50 % der Falle (Erwachsene: bis zu 90 %) mittels kontrastmittelverstarkter Bildgebung identifiziert werden. Dilatierte Bronchialarterien zeigen ein erhohtes Risiko fur Hamoptysen an. Die Protonen-MRT ist das einzige Verfahren, welches strukturelle und funktionelle Veranderungen in einem Untersuchungsgang zeigt. Bei der Erfassung des Schweregrads aller Veranderungen hilft die strukturierte Befundung anhand eines Scoringsystems. Die MRT der Lunge bei Mukoviszidose kann heute als etabliertes Standardverfahren an erfahrenen Zentren routinemasig durchgefuhrt werden. Seit Neuestem wird sie auch im Rahmen von klinischen Studien als Endpunkt verwendet.

Die Computertomographie (CT) bietet durch ihre hohe Detailauflosung und die Moglichkeit der multidimensionalen Rekonstruktion eine zuverlassige Moglichkeit der Diagnostik und Verlaufskontrolle morphologischer Zeichen der Mukoviszidose (zystische Fibrose, CF) der Lunge. Standardisierte Leitlinien zur technischen Durchfuhrung bestehen aktuell noch nicht, werden aber fur verschiedene Altersgruppen diskutiert. Zentral bleibt die Applikation ionisierender Strahlung, die stets – jedoch auch besonders in Hinblick auf uberwiegend junge CF-Patienten – einer strengen rechtfertigenden Indikation bedarf. Der Einsatz von CT-Kontrastmitteln ist meist fur Notfallindikationen erforderlich. In der CT finden sich bereits fruhzeitig typische Lungenveranderungen der CF wie Bronchiektasien, Schleimretentionen („mucus plugging“) oder Zeichen der Uberblahung (Air Trapping). Mit der Zeit wurden verschiedene Bewertungsrichtlinien fur eine systematische Schweregradeinteilung etabliert. Diese dienen nicht nur zur individuellen Krankheitseinschatzung, sondern auch im Rahmen von Studien zur Verlaufsbeurteilung und Therapiekontrolle. Unter der technischen Entwicklung der CT kommen auch zunehmend computerbasierte Nachverarbeitungsprogramme zur halbautomatischen Auswertung und Quantifizierung zum Einsatz. Diese sollen nicht nur den klinischen Alltag erleichtern, sondern auch dazu beitragen, standardisierte und quantitative Protokolle und Auswertungen, z. B. im Rahmen von Studien, zu ermoglichen. Parallel wird nach Alternativen der Bildgebung gesucht. Zunehmende Bedeutung gewinnt die Magnetresonanztomographie (MRT), die durch verbesserte Bildqualitat sowie spezialisierte Protokolle an Bedeutung gewinnt und die CT fur Langzeitverlaufe an zahlreichen spezialisierten Zentren bereits haufig ablost.

ZusammenfassungSeit dem letzten gemeinsamen Positionspapier der Deutschen Röntgengesellschaft und der Deutschen Gesellschaft für Pneumologie und Beatmungsmedizin im Jahr 2011 hat sich die Datenlage zur Lungenkrebsfrüherkennung mit Niedrigdosis-CT deutlich erweitert und in der 2018 revidierten S3-Leitlinie Lungenkarzinom wird eine schwache Empfehlung zur Lungenkrebsfrüherkennung mit Niedrigdosis-CT in einem qualitätsgesicherten Früherkennungsprogramm ausgesprochen. Diese neuen Entwicklungen erforderten eine Neupositionierung der beteiligten Fachgesellschaften. Das vorliegende Positionspapier beschreibt Grundzüge eines qualitätsgesicherten Früherkennungsprogramms für Lungenkrebs in Deutschland.

Fokale Knorpelschaden sind haufige Pathologien der gewichtstragenden Gelenke. Die klinische Prasentation reicht von symptomlosen Patienten bis hin zu starksten, schmerzbedingten Einschrankungen der Mobilitat. Sie sind ein bedeutender Risikofaktor fur die Entwicklung degenerativer Gelenkerkrankungen. Fur die Behandlung fokaler Knorpellasionen stehen dem Orthopaden multiple chirurgische Verfahren zur Verfugung. Muskuloskeletale Radiologen sollen die Grundzuge der operativen Verfahren wie auch die typische postoperative Bildgebung kennen, um zuverlassig Abweichungen von einem normalen postoperativen Verlauf zu erkennen. Ziel dieses Ubersichtsartikels ist die Erlauterung der verschiedenen Methoden zur operativen Behandlung fokaler Knorpelschaden und deren typische MR-morphologische Darstellung. Es wurde eine PubMed-Literaturrecherche durchgefuhrt zu den Stichworten „focal articular cartilage lesions“, „chondral lesions“, „MOCART“, „Microfracture“, „Osteochondral Autograft Transfer“, „mosaicplasty“, „Osteochondral Allograft Transplantation“, „OATS“, „OCT“, „Autologous Chondrocyte Implantation“, „ACI“, „Matrix-Assisted Chondrocyte Implantation“, „Autologous Matrix-induced Chondrogenesis“. Die operativen Methoden zur Behandlung fokaler Knorpellasionen werden erklart, und die postoperative Bildgebung wird dargestellt.

Postoperative lymphorrhea can occur after different surgical procedures and may prolong the hospital stay due to the need for specific treatment. In this work, the therapeutic significance of the radiological management of postoperative lymphorrhea was assessed and illustrated.A standardized search of the literature was performed in PubMed applying the Medical Subject Headings (MeSH) term "lymphangiography." For the review, the inclusion criterion was "studies with original data on Lipiodol-based Conventional Lymphangiography (CL) with subsequent Percutaneous Lymphatic Intervention (PLI)." Different exclusion criteria were defined (e.g., studies with15 patients). The collected data comprised of clinical background and indications, procedural aspects and types of PLI, and outcomes. In the form of a pictorial essay, each author illustrated a clinical case with CL and/or PLI.Seven studies (corresponding to evidence level 4 [Oxford Centre for Evidence-Based Medicine]) accounting for 196 patients were included in the synthesis and analysis of data. Preceding surgery resulting in postoperative lymphorrhea included different surgical procedures such as extended oncologic surgery or vascular surgery. Central (e.g., chylothorax) and peripheral (e.g., lymphocele) types of postoperative lymphorrhea with a drainage volume of 100-4000 ml/day underwent CL with subsequent PLI. The intervals between "preceding surgery and CL" and between "CL and PLI" were 2-330 days and 0-5 days, respectively. CL was performed before PLI to visualize the lymphatic pathology (e.g., leakage point or inflow lymph ducts), applying fluoroscopy, radiography, and/or computed tomography (CT). In total, seven different types of PLI were identified: (1) thoracic duct (or thoracic inflow lymph duct) embolization, (2) thoracic duct (or thoracic inflow lymph duct) maceration, (3) leakage point direct embolization, (4) inflow lymph node interstitial embolization, (5) inflow lymph duct (other than thoracic) embolization, (6) inflow lymph duct (other than thoracic) maceration, and (7) transvenous retrograde lymph duct embolization. CL-associated and PLI-associated technical success rates were 97-100% and 89-100%, respectively. The clinical success rate of CL and PLI was 73-95%. CL-associated and PLI-associated major complication rates were 0-3% and 0-5%, respectively. The combined CL- and PLI-associated 30-day mortality rate was 0%, and the overall mortality rate was 3% (corresponding to six patients). In the pictorial essay, the spectrum of CL and/or PLI was illustrated.The radiological management of postoperative lymphorrhea is feasible, safe, and effective. Standardized radiological treatments embedded in an interdisciplinary concept are a step towards improving outcomes.

Contrast-enhanced computed tomography (CT) is a convenient method to visualize left atrial appendage (LAA) thrombi. We determined whether diagnostic accuracy improves by including dual-energy as compared to transesophageal echocardiography (TEE). Furthermore, the influence of protocol parameters on radiation dose were quantified.Patients were assigned to the different CT protocols. All CTs were assessed qualitatively for presence of LAA thrombi and dual-energy CT scans quantitatively for iodine concentration. TEE was assessed qualitatively for the presence of thrombi.Of 32 enrolled patients, 6 had a thrombus in TEE. Qualitative CT assessment yielded 83% sensitivity and 88% specificity. In the 26 patients who underwent dual-energy CT, median iodine concentration was 8.6 mg/cmCT provides good diagnostic accuracy for detecting LAA thrombi, which can further be improved if iodine density measurements by dual-energy are incorporated. With an optimized protocol, reasonably low radiation dose can be achieved.

Quantitative CT analysis allows for measurement of static lung volumes. Objective: To evaluate the value of QCT analysis before and after the use of tiotropium/olodaterol respimat in patients with mild/moderate therapy naive COPD patients. Methods: Patients which newly diagnosed COPD and another radiological finding, which indicated a follow-up CT within 6-12 weeks, were put on tiotropium/olodaterol and followed up. Non-enhanced thin-sections were acquired in paired inspiratory/expiratory breath-hold and quantified using YACTA. Results: 10 patients were enrolled (7males, mean age 64 y.). Mean initial VC was 3,45 l (SD 1,2 l) and RV 3,9 l (SD 1,3 l) measured by bodyplethysmography and VC was 3,2 l (SD 1,1 l) and RV 3,8 l (SD 1,3 l) by QCT. At follow up, the VC improved by 130 ml and RV decreased by480 ml in the body as well in the QCT (VC +210 ml, RV-600ml). IN QCT the air-trapping was reduced by converting severe into mild air-trapping or normalization. The correlations of the measurements were high and were also able to show regional differences of the improvement (fig.1). Conclusions: QCT calculated static lung function measurements correlating high with the lung function measurements before and after a tiotropium/olodaterol Respimat treatment. Additional value might be due to the possibility of analysis of regional aspects for identification of failure or eventually local treatment.

Disease severity and mortality in patients with cystic fibrosis (CF) is mainly determined by (progressive) pulmonary lung disease. Early diagnosis and therapy are important and of prognostic value to conserve lung function.Primary imaging techniques for lung imaging are x‑ray and computed tomography (CT) to monitor disease severity and regional distribution.Radiation-free imaging techniques such as magnetic resonance imaging (MRI) have gained interest over the last decade in order to prevent radiation damage.The main findings of CF lung disease are airway wall thickening, bronchiectasis, and mucus plugging, which are found in up to 60% of preschool age children. Pleural abnormalities and consolidations are often associated with pulmonary exacerbation. Young CF patients often show a mosaic pattern as functional changes and also perfusion defects can be seen from birth in 50% of CF patients by contrast-enhanced perfusion imaging, and in up to 90% of adult patients, with varying degrees of severity. Dilated bronchial arteries indicate an increased risk for hemoptysis.Proton MRI is the sole imaging technique that can show structural and functional lung changes in one examination. Structured assessment using a scoring system helps to systematically grade the extent and severity of all CF-associated changes.Lung MRI for cystic fibrosis has been recently established as a clinical standard examination and is routinely performed at experienced centers. More recently, it has also been used as an endpoint within the framework of clinical studies.

With its high detail of morphological changes in lung parenchyma and airways as well as the possibilities for three-dimensional reconstruction, computed tomography (CT) represents a solid tool for the diagnosis and follow-up in patients suffering from cystic fibrosis (CF). Guidelines for standardized CT image acquisition in CF patients are still missing. In the mostly younger CF patients, an important issue is the well-considered use of radiation in CT imaging. The use of intravenous contrast agent is mainly restricted to acute emergency diagnostics. Typical morphological findings in CF lung disease are bronchiectasis, mucus plugging, or signs of decreased ventilation (air trapping) which can be detected with CT even in early stages. Various scoring systems that have become established over time are used to grade disease severity and for structured follow-up, e.g., in clinical research studies. With the technical development of CT, a number of postprocessing software tools were developed to help clinical reporting and overcome interreader differences for a standardized quantification. As an imaging modality free of ionizing radiation, magnetic resonance imaging (MRI) is becoming increasingly important in the diagnosis and follow-up of CF patients and is already frequently a substitute for CT for long-term follow-up at numerous specialized centers.

The European Society of Radiology (ESR) and European Respiratory Society (ERS) published their joint statement paper on lung cancer screening (LCS), on 12 February 2020. This document joins and completes previous recommendations on LCS with specific emphasis on the analysis of issues encountered in the practical implementation of LCS in the community. Major milestones to enable the most efficient and equal dissemination of LCS are recognised as engagement of all stakeholders (e.g. candidate/participant, general practitioners, up to the specialised LCS facility), quality assurance, and primary prevention in the form of provision of counselling for smoking cessation.

Non-alcoholic fatty liver disease (NAFLD) can lead to functional liver impairment and severe comorbidities. Beyond energy balance, several dietary factors may increase NAFLD risk, but human studies are lacking. The aim of this cross-sectional study was to investigate the associations between food consumption (47 food groups, derived Mediterranean and Dietary Approaches to Stop Hypertension (DASH) diet quality scores) and liver fat content (continuous scale and NAFLD, i.e., &gt, 5% liver fat content). Liver fat content was measured by magnetic resonance imaging (MRI) in 136 individuals (BMI: 25&ndash, 40 kg/m2, age: 35&ndash, 65, 50.7% women) and food intake was recorded by food frequency questionnaires (FFQs). Associations between food items and liver fat were evaluated by multi-variable regression models. Intakes of cake and cookies as well legumes were inversely associated with liver fat content, while positive associations with intakes of high-fat dairy and cheese were observed. Only cake and cookie intake also showed an inverse association with NAFLD. This inverse association was unexpected, but not affected by adjustment for reporting bias. Both diet quality scores were inversely associated with liver fat content and NAFLD. Thus, as smaller previous intervention studies, our results suggest that higher diet quality is related to lower liver fat, but larger trials with iso-caloric interventions are needed to corroborate these findings.

Objectives To compare image quality and metal artifact reduction between virtual monochromatic spectral imaging (VMSI), linearly blended dual-energy (DE) and single-energy (SE) images, each with and without dedicated iterative metal artifact reduction (iMAR) for CT-guided biopsy. Materials and methods A biopsy trocar was positioned in the liver of six pigs. DE (Sn140/100kVp) and SE (120kVp/200mAs) acquisitions were performed with equivalent dose. From dual-energy datasets DE Q30-3 images and VMSI between 40-180 keV in steps of 20 keV were generated. From SE datasets I30-3 images were reconstructed. All images were reconstructed with and without iMAR. Objective image quality was analyzed applying density measurements at standardized positions (e.g. trocar tip and liver parenchyma adjacent to the trocar tip) and semi-automated threshold based segmentation. Subjective image quality was performed using semi-quantitative scores. Analyses were performed by two observers. Results At the trocar tip quantitative image analysis revealed significant difference in CT numbers between reconstructions with iMAR compared to reconstructions without iMAR for VMSI at lower keV levels (80 and 100 keV; p = 0.03) and DE (p = 0.03). For liver parenchyma CT numbers were significantly higher in VMSI at high keV compared to low keV (p≤0.01). VMSI at high keV also showed higher CT numbers compared to DE and SE images, though not the level of statistical significance. The best signal-to-noise ratio for VMSI was at 80 keV and comparable to DE and SE. Noise was lowest at 80 keV and lower than in DE and SE. Subjective image quality was best with VMSI at 80 keV regardless of the application of iMAR. iMAR significantly improved image quality at levels of 140 keV and 160 keV. Interreader-agreement was good for quantitative and qualitative analysis. Conclusion iMAR improved image quality in all settings. VMSI with iMAR provided metal artifact reduction and better image quality at 80 keV and thus could improve the accurate positioning in CT-guided needle biopsy. In comparison, DE imaging did not improve image quality compared to SE.

BACKGROUND AND PURPOSE: The type and composition of an embolic agent have a relevant influence on the performance of endovascular embolization. The aim of this study was to investigate a new version of the liquid embolic agent precipitating hydrophobic injectable liquid (PHIL) with extra-low-viscosity in an in vivo embolization model. MATERIALS AND METHODS: Twenty-four embolization procedures were performed in the porcine rete mirabile. Eight embolizations were performed with PHIL 25% low viscosity, Squid 12, and standard PHIL 25%, respectively. Procedure time, required volume of embolic agent, visibility of the embolic agent, embolization control, embolization extent (ie, penetration of the rete mirabile), amount of reflux, and degree of embolization distal to the rete mirabile were assessed. RESULTS: All embolic agents were adequately visible. The embolization extent was not significantly different among the 3 investigated agents; however, there was a tendency toward a higher embolization extent for PHIL 25% low viscosity (median embolization extent: 88% [PHIL 25% low viscosity]; 65% [Squid 12]; 60% [PHIL 25%]; P = .146). The amount of reflux was significantly lower for the extra-low-viscosity agents PHIL 25% low viscosity and Squid 12 compared with the standard PHIL 25% (median reflux distance: 8 mm [PHIL 25% low viscosity]; 6 mm [Squid 12]; 17 mm [PHIL 25%]; P = .011). All other embolization features did not differ among agents. CONCLUSIONS: PHIL 25% low viscosity is a promising liquid embolic agent for endovascular embolization, featuring effective distal penetration, adequate visibility, a low amount of reflux, and good flow control.

To investigate radiopacity, size and size calibration, morphology, and vascular distribution of inherently radiopaque microspheres in vitro and in a pig embolization model. We compared three types of microspheres: DCBead™ (size 100–300 µm) and Embozene™ (250 µm) as clinically established microspheres, and the prototype Visible (250 µm) that contains additional radiopaque material. Size and size calibration of microspheres were examined by laser diffraction. Pulmonary artery embolization was performed in 12 pigs, and radiopacity was examined by in vitro micro-computed tomography (CT), in vivo cone-beam CT, and ex vivo micro-CT after killing. Morphology and vascular distribution of microspheres were microscopically examined. In in vitro and ex vivo micro-CT, radiopacity of Visible was higher than that of Embozene™, whereas DCBead™ showed no radiopacity. In in vivo cone-beam CT, radiopacity was observed with Visible but not with Embozene™ and DCBead™. Laser diffraction revealed that 7.0% (Visible), 6.5% (Embozene™), and 22.5% (DCBead™) of microspheres were smaller than 223.5 μm. Visible and Embozene™ microspheres were very often located in bronchiolus-associated arteries, but rarely in subsegmental and capillary arteries, whereas DCBead™ were very often and often detected in bronchiolus-associated arteries and capillary arteries, respectively (and rarely in subsegmental arteries). After pulmonary artery embolization, Visible but not Embozene™ or DCBead™ provide in vivo radiopacity in cone-beam CT. In contrast to non-narrow-size-calibrated DCBead™, pulmonary artery embolization with narrow-size-calibrated Visible and Embozene™ result in a predictable arterial distribution without embolization-related hemorrhagic lung infarction.

In dieser Studie wurden Methoden der Tumorlastquantifizierung in der Ganzkorper-Magnetresonanztomographie (GK-MRT) beim Multiplen Myelom untersucht und mit krankheitstypischen Parametern in Serum und Knochenmark korreliert. Die GK-MRT von 52 Patienten mit fokalem Befallsmuster wurden retrospektiv ausgewertet. 700 fokale Lasionen (im Folgenden Lasionen genannt) wurden in kugelig und nicht-kugelig eingeteilt, manuell segmentiert und der langste Durchmesser (LD) bestimmt. Gesamtanzahl und -volumen der Lasionen wurden mit klinischen Parametern und Prognose sowie der LD mit dem segmentierten Volumen (SV) der Lasionen korreliert. SV und per Kugelformel anhand dem LD berechnetes Volumen (BV) wurden auf Ubereinstimmung analysiert. Es zeigten sich keine signifikanten Korrelationen von Gesamtanzahl/-volumen der Lasionen mit den uberwiegend normwertigen Parametern oder der Prognose. 10 % der Lasionen waren kugelig. SV und LD korrelierten signifikant fur die einzelnen Lasionen und auf Patientenebene. Das SV war bei Lasionen

Aim To define practical limitations of diagnostic image quality for recently introduced turbo high-pitch scan mode (THP) in third-generation dual-source computed tomography (CT). Materials and Methods Two hundred and twenty-nine consecutive patients undergoing CT coronary angiography were included in this retrospective single-centre analysis. A contrast-enhanced volume dataset was acquired in THP. Image quality of coronary segments was classified as diagnostic or non-diagnostic by three blinded readers. Segments were stated as non-diagnostic if at least one of three readers could neither exclude nor confirm significant stenoses. Multivariable logistic regression was used to assess relationships between number of non-diagnostic segments and common influencing factors. Results Median effective radiation dose was 0.6 (interquartile range [IQR], 0.4–0.8) mSv overall and 0.3 (IQR, 0.3–0.4) mSv in the 70 kV subgroup of this middle aged, predominantly pre-obese cohort (age: 61 [IQR, 52–67] years; body mass index [BMI]: 26 [IQR, 23–29] kg/m2) with a low–moderate median Agatston score (AS) 0 (IQR, 0–70). Diagnostic image quality was found in 98.1% of 3,678 coronary segments. AS was independently associated with diagnostic image quality (B=0.34; p=0.02), whereas heart rate, BMI, and presence of arrhythmia were not. The portion of diagnostic coronary segments decreased slightly in obese patients with heart rates >65 beats/min and dropped significantly in patients with an AS >600 (p=0.003). Conclusion THP enables CT coronary angiography with minimal radiation exposure and is most appropriate in non-obese patients with stable sinus rhythm ≤65 beats/min and a calcium score ≤600.