Nephrogene systemische Fibrose (NSF): Wie hoch ist das Risiko und wie können wir es vermeiden?

Zusammenfassung: Das Krankheitsbild der nephrogenen systemischen Fibrose, das nach Durchführung einer Gadolinium unterstützen Magnetresonanztomographie/-angiographie bei Patienten mit schwerer Niereninsuffizienz auftreten kann, hat zu einer massiven Verunsicherung in der Anwendung dieser wertvollen Untersuchungstechnik geführt. Das Ziel der vorliegenden Arbeit ist es, neben der Diskussion des Krankheitskonzepts, der zugrundeliegenden Pathophysiologie, der Klinik und der therapeutischen Optionen, die Risikofaktoren zu beleuchten und Konzepte der Prävention aufzuzeige

Sensory evaluation of Extra Virgin Olive Oil (EVOO) extended to include the quality factor "harmony"

Sensory evaluation of olive oil, meaning the official organoleptic assessment of olive oil respectively the "Panel Test" (PT), is based on the standards of the International Olive Council (IOC), as well as on the Regulation (EC) 640/2008 of the European Commission. These regulations lead to the classification of olive oil as "extra virgin" (EVOO), "virgin" (VOO) or "lampant", which however is not sufficient to clearly discriminate between different quality levels within the grade EVOO. The objective of the study at hand was to develop and validate an objective sensory evaluation method for the quality certification of olive oil within the grade EVOO. A new rating system, including a detailed description and evaluation of the complexity and persistence of flavour, was established. First, a comparison between different profile sheets from various olive oil competitions (Ercole Olivario, Premio Biol, Leone D'Oro Mario Solinas Award, among others) and the official profile sheet from the IOC/EC for the panel test (PT) took place. In consecutive steps the basic test procedure from the panel test (PT) then was extended with additional sensory descriptors. Two trained olive oil panels (the German Olive Oil Panel (DOP) and the Swiss Olive Oil Panel (SOP)) were further educated to profile various green and ripe aroma components and to evaluate the complexity of the perceived aroma components and their persistency (descriptor: "harmony/persistency"). This extended methodology was cross-validated over a time period of 3 years between the two panels (DOP/SOP)

Three-dimensional dynamic MR-hysterosalpingography; a new, low invasive, radiation-free and less painful radiological approach to female infertility

BACKGROUND: The purpose of this study was to propose a new method for imaging the uterine cavity and Fallopian tube patency by three-dimensional dynamic magnetic resonance hysterosalpingography (3D dMR-HSG) and to analyse if, by using a higher viscosity contrast solution, direct visualization of the Fallopian tubes may be achieved by this new technique. METHODS: 10 consecutive infertile women underwent 3D dMR-HSG and conventional HSG as gold standard. 3D dMR-HSG consisted of injection of 20 ml of a gadolinium-polyvidone solution into the uterine cavity while acquiring five consecutive three-dimensional (3D) T1-weighted MR-sequences. RESULTS: In three patients the catheter became dislodged during 3D dMR-HSG. However, in one of these patients the examination was still partially diagnostic. Imaging findings of 3D dMR-HSG showed good correlation with conventional hysterosalpingography and allowed 3D imaging of the uterine cavity and of Fallopian tube patency in 8/10 patients and direct visualization of the Fallopian tubes in 5/7 patients. CONCLUSION: 3D dMR-HSG represents a new and promising imaging approach to female infertility causing less pain and avoiding exposure of the ovaries to ionizing radiation. By using a higher viscosity MR-contrast agent it allows not only visualization of uterine cavity and Fallopian tube patency but also direct visualization of Fallopian tube

Total-body contrast-enhanced MRA on a short, wide-bore 1.5-T system: intra-individual comparison of Gd-BOPTA and Gd-DOTA

Total-body contrast-enhanced MRA (CE-MRA) provides information of the entire vascular system according to a one-stop-shop approach. Short, wide-bore scanners have not yet been used for total-body CE-MRA, probably due to their restricted field of view in the z-direction. The purpose of this feasibility study is to introduce an image protocol for total-body MRA on a short, wide-bore system. The protocol includes five to six table-moving steps and two injection runs. Two pharmacologically different contrast materials (CM) were applied in ten healthy volunteers in view of possible CM-dependent influences on the protocol outcome (Gd-Bopta, Gd-Dota). Differences consisted of significantly higher CNR with Gd-Bopta with a mean of 73.8 ± 38.7 versus 69.1 ± 34.3 (p = 0.008), significantly better arterial visualization values with Gd-Dota with a mean of 1.26 ± 0.44 versus 1.53 ± 0.73 (p = 0.003) and a tendency to less venous overlay with Gd-Dota, mean 1.19 ± 0.44 and 1.34 ± 0.72, respectively (p = 0.065) (two-tailed Wilcoxon matched-pairs test). Overall 94% of the steps were valued as qualitatively excellent or good. The good results with both CM suggest a transfer to further patient evaluatio

Low-dose intra-arterial contrast-enhanced MR aortography in patients based on a theoretically derived injection protocol

Multiple intra-arterial contrast agent injections are necessary during MR-guided endovascular interventions. In respect to the approved limits of maximum daily gadolinium dose, a low-dose injection protocol is mandatory. The objective of this study was to derive and apply a low-dose injection protocol for intra-arterial 3D contrast-enhanced MR aortography in patients. Injection rate (Qinj), concentration of injected gadolinium [Gd]inj and aortal blood flow rate (Qblood) were included for the theoretical evaluation of signal intensity (SI) of the arterial lumen. SI simulations were carried out at Qinj=2 versus 4ml/s in the [Gd]inj range between 0-500mM. Qinj and [Gd]inj with SI above the 75% threshold of the maximal SI were regarded as optimal injection parameters. [Gd]inj=50mM and Qinj=4ml/s were considered as optimal and were administered in five patients for 3D MR aortography. All images revealed clear delineation of the abdominal aorta and its major branches. Mean±SD of contrast-to-noise ratios of the abdominal aorta, common iliac and renal artery were 70.2±15.2, 58.6±12.3 and 67.4±12.3. Approximately seven intra-aortal injections would be permissible in patients during MR-guided interventions without exceeding the maximal dose of gadoliniu

Cycle-finite module categories

We describe the structure of module categories of finite dimensional algebras over an algebraically closed field for which the cycles of nonzero nonisomorphisms between indecomposable finite dimensional modules are finite (do not belong to the infinite Jacobson radical of the module category). Moreover, geometric and homological properties of these module categories are exhibited

Rationale Schnittbildgebung des hepatozellulären Karzinoms: Die Herausforderung multimodaler Diagnosekriterien

Zusammenfassung: Klinisches/methodisches Problem: CT und MRT bilden den Goldstandard in der bildgebenden Diagnostik des hepatozellulären Karzinoms (HCC). Beide Verfahren erlauben als alleinige Untersuchung bei entsprechendem Kontrastmittelverhalten die Diagnose eines HCC. Eine radiologische Herausforderung stellen immer noch die Detektion von HCC-Läsionen  2cm sehr hohe Detektionsraten zwischen 90 und 100 %. Für Läsionen zwischen 1 und 2cm bestehen Vorteile der MRT mit Sensitivitäten zwischen 80 und 90 % gegenüber 60-75 % der CT. Die MRT-Diagnostik profitiert neben den multimodalen Diagnosekriterien zusätzlich vom Einsatz leberspezifischer Kontrastmittel, insbesondere in Kombination mit der Diffusionsbildgebung, wobei sowohl eine Erhöhung der Sensitivät als auch der diagnostischen Genauigkeit für Läsionen < 2cm nachgewiesen werden konnte. Bezüglich der Abgrenzung des HCC von anderen nodulären Herdläsionen der zirrhotischen Leber hat sich gezeigt, dass die gleichzeitig vorliegende arterielle Hypervaskularisation und Hypointensität in der hepatobiliären Phase als spezifisch für das Vorliegen eines HCC einzustufen ist. Zudem ist ein hypointenses Signal in der hepatobiliären Phase mit einem hohen Vorhersagewert von bis zu 100 % für das Vorliegen eines High-grade-dysplastischen Knotens oder HCC assoziiert. Bewertung: Die MRT unter Berücksichtigung von hepatobiliärer und diffusionsgewichteter Bildgebung ("diffusion-weighted imaging", DWI) stellt heutzutage die beste nichtinvasive Bilddiagnostik für die Detektion des HCC sowie zur Charakterisierung von Knoten in der zirrhotischen Leber dar, mit deutlichen Vorteilen gegenüber der CT bei der Detektion kleiner Läsionen < 2cm sowie der Dignitäts- und Prognoseeinschätzung hypovaskulärer Vorstufen im Rahmen der Hepatokarzinogenese. Empfehlung für die Praxis: Sowohl die MRT als auch die CT ermöglichen einen hohen Standard zur Diagnostik des HCC in der zirrhotischen Leber, mit Vorteilen der MRT bzgl. Detektionsrate und Spezifität. Die CT bietet für den klinischen Alltag eine schnelle, robuste sowie gut verfügbare Modalität mit Vorteilen bei Patienten in reduziertem Allgemeinzustand sowie eingeschränkter Compliance

Unenhanced helical computed tomography vs intravenous urography in patients with acute flank pain: accuracy and economic impact in a randomized prospective trial

Abstract.: Unenhanced helical computed tomography (UHCT) has evolved into a well-accepted alternative to intravenous urography (IVU) in patients with acute flank pain and suspected ureterolithiasis. The purpose of our randomized prospective study was to analyse the diagnostic accuracy of UHCT vs IVU in the normal clinical setting with special interest on economic impact, applied radiation dose and time savings in patient management. A total of 122 consecutive patients with acute flank pain suggestive of urolithiasis were randomized for UHCT (n=59) or IVU (n=63). Patient management (time, contrast media), costs and radiation dose were analysed. The films were independently interpreted by four radiologists, unaware of previous findings, clinical history and clinical outcome. Alternative diagnoses if present were assessed. Direct costs of UHCT and IVU are nearly identical (310/309 Euro). Indirect costs are much lower for UHCT because it saves examination time and when performed immediately initial abdominal plain film (KUB) and sonography are not necessary. Time delay between access to the emergency room and start of the imaging procedure was 32h 7min for UHCT and 36h 55min for IVU. The UHCT took an average in-room time of 23min vs 1h 21min for IVU. Mild to moderate adverse reactions for contrast material were seen in 3 (5%) patients. The UHCT was safe, as no contrast material was needed. The mean applied radiation dose was 3.3mSv for IVU and 6.5mSv for UHCT. Alternative diagnoses were identified in 4 (7%) UHCT patients and 3 (5%) IVU patients. Sensitivity and specificity of UHCT and IVU was 94.1 and 94.2%, and 85.2 and 90.4%, respectively. In patients with suspected renal colic KUB and US may be the least expensive and most easily accessable modalities; however, if needed and available, UHCT can be considered a better alternative than IVU because it has a higher diagnostic accuracy and a better economic impact since it is more effective, faster, less expensive and less risky than IVU. In addition, it also has the capability of detecting various additional renal and extrarenal pathologie