Pseudoaneurysm in the iliac fossa after renal transplantation—treatment with ultrasound-guided thrombin injection

We report the case of a 57-year-old female who developed a large pseudoaneurysm of the right circumflex iliac artery 15 months after renal transplantation. Minimal invasive treatment was successfully performed with ultrasound-guided thrombin injection using the B-flow mod

Simulation des Blutflusses in der abdominellen Aorta: Die numerische Simulation des Blutflusses in abdominellen Aortenaneurysmen vor und nach Intervention

Zusammenfassung: Das Ziel der numerischen Simulation des Blutflusses in der Aorta ist, die Mechanik der Entstehung von Aortenaneurysmen im Hinblick auf das Rupturrisiko zu untersuchen und die Wirkungen interventioneller Maßnahmen zu beschreiben. Die Grundlage der numerischen Simulation sind virtuelle Modelle von Gefäßen und die physikalischen Eigenschaften der Gefäßbestandteile, des Blutes und der Strömung. Basierend auf diesen Angaben werden mit Hilfe numerischer Methoden die strömungsmechanischen Probleme des Blutflusses näherungsweise gelöst. Die Ergebnisse können dann quantitativ und qualitativ dargestellt werden. Die Ergebnisse der numerischen Flusssimulation zeigen, dass in abdominellen Aortenaneurysmen die Höhe des Wanddrucks, der von entscheidender Bedeutung für das Rupturrisiko ist, von verschiedenen Faktoren, wie z.B. der Lage des Wandthrombus, abhängt. In Modellen mit Stentgrafts wurden mit Hilfe der numerischen Simulation Faktoren, welche die Stentgraftmigration beeinflussen, untersucht. Obwohl die numerische Simulation des Blutflusses noch einige Limitationen aufweist, zeigen aktuelle Studien, dass die Methode das Potenzial hat, um in Zukunft eine dedizierte Beurteilung des Rupturrisikos von Aortenaneurysmen vorzunehme

USPIO-enhanced magnetic resonance imaging of the knee in asymptomatic volunteers

The aim of this study was to compare signal characteristics of the synovium in knees of asymptomatic volunteers before and after intravenous administration of ultrasmall superparamagnetic iron oxide particles (USPIO). Ten knees of 10 asymptomatic volunteers were examined before and 36h after intravenous administration of USPIO on a 1.5-T MR system using T1-weighted spin-echo, T2-weighted fast spin-echo, T2*-weighted gradient-echo (GRE), and short inversion time inversion-recovery sequences. In addition, synovial perfusion was measured using Gd-enhanced GRE imaging during the first imaging session. Images were analyzed qualitatively for any visual changes before and after USPIO administration. Signal-to-noise ratios (SNR) of the synovium were determined on unenhanced and USPIO-enhanced sequences. All MR images were reviewed for presence of any degenerative changes. Qualitative image analysis revealed no visually detectable changes of any knee joint before and after USPIO administration. The SNR values of the synovium on T1w, T2w, and T2*w images before and after USPIO administration showed no significant difference (T1, P = 0.86; T2, P = 0.95; T2*, P = 0.86). None of the volunteers showed any relevant degenerative changes of the knee and synovial perfusion was within normal limits. In knees of asymptomatic volunteers without any relevant degenerative changes and normal synovial perfusion neither visual changes nor changes of SNR values of the synovium can be depicted after USPIO administration. This means that USPIO-enhanced MRI may be used for assessment of knee disorders with increased macrophage activit

Pseudoaneurysm in the iliac fossa after renal transplantation—treatment with ultrasound-guided thrombin injection

We report the case of a 57-year-old female who developed a large pseudoaneurysm of the right circumflex iliac artery 15 months after renal transplantation. Minimal invasive treatment was successfully performed with ultrasound-guided thrombin injection using the B-flow mod

Radiation dose estimates in dual-source computed tomography coronary angiography

The purpose of this study was to quantify radiation dose parameters of dual-source CT coronary angiography. Eighty patients underwent contrast-enhanced, retrospectively ECG-gated dual-source CT coronary angiography with heart rate-adapted ECG pulsing using two algorithms: In 40 patients, the tube current was reduced to 20% (A(min1)) of the normal tube current (A(max)) outside the pulsing window; in 40 patients tube current was reduced to 4% (A(min2)) of A(max). Mean CTDI(vol) in the A(min1) group was 45.1 +/- 3.6 mGy; the mean CTDI(vol) in the A(min2) group was 39.1 +/- 3.2 mGy, with CTDI(vol) in the A(min2) group being significantly reduced when compared to the A(min1) group (P < 0.001). A significant negative correlation was found between CTDI(vol) and heart rate in group A(min1) (r = -0.82, P < 0.001), whereas no correlation was found between CTDI(vol) and heart rate in group A(min2) (r = -0.066). Using the conversion coefficient for the chest, dual-source CT coronary angiography resulted in an estimated mean effective dose of 8.8 mSv in the A(min1) group and 7.8 mSv in the A(min2). Radiation exposure of dual-source CT coronary angiography using an ECG-pulsing protocol reducing the tube current to 20% significantly decreases with increasing heart rates, despite using wider pulsing windows at higher heart rates. When using a protocol with reduced tube current of 4%, the radiation dose is significantly lower, irrespective of the heart rate

Contrast-enhanced MR cholangiography with Gd-EOB-DTPA in patients with liver cirrhosis: visualization of the biliary ducts in comparison with patients with normal liver parenchyma

The purpose of this study was to assess the quality of biliary duct visualization using Gd-EOB-DTPA-enhanced magnetic resonance cholangiography (EOB-MRC) in patients with liver cirrhosis. Forty adult patients with liver cirrhosis (cirrhosis group) and 20 adult individuals with normal liver parenchyma (control group) underwent EOB-MRC using T1-weighted GRE imaging up to 180 min after Gd-EOB-DTPA administration. Two observers assessed the visualization of each biliary structure and the overall anatomical visualization of the biliary tree. Child-Pugh, MELD score and laboratory findings were compared. The grade of visualization for each evaluated biliary structure was statistically different in the two groups (P = 0.004 to /=11 and total serum bilirubin levels >/=30 mumol/l. Consecutively, EOB-MRC in patients with liver cirrhosis resulted in a decreased or even non-visualization of the biliary tree in a substantial percentage of patients