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Magnetic resonance imaging (MRI) provides sufficient information with regard to specific soft-tissue injuries in the knee, but it is not generally used to evaluate acute tibial plateau fractures. The aim of the present study was to determine whether the amount of tibial plateau fracture depression on multi-detector computed tomography (MDCT) scans correlates with the incidence of associated soft-tissue injuries on MRI.A total of 54 consecutive patients with a mean age of 51.2 years (SD = 18.3) were included in this retrospective study. All patients were admitted to the emergency department of a university clinic with acute tibial plateau fracture. The amount of articular depression was assessed from MDCT scans. Magnetic resonance images were evaluated for crucial and collateral ligament injury, meniscal tears, and patellar retinaculum lesions.Logistic regression revealed a significant impact of increasing tibial plateau fracture depression on the incidence of meniscus lateralis tears (P = 0.025) and anterior cruciate ligament lesions (P = 0.018). Analysis of covariance demonstrated a significant correlation between the amount of articular depression and absolute number of soft-tissue injuries (P = 0.001).Articular depression is a potential predictor of specific meniscal and ligamentous injuries in acute tibial plateau fracture. Magnetic resonance imaging is generally recommended with respect to associated soft-tissue injuries, especially in cases with distinct tibial plateau fracture depression on multi-detector computed tomography scans.Case series, Level IV.

Zielsetzung: Herleitung einer Formel zur schnellen Abschatzung der Volumina von Perikardergussen (PE) in der Multidetektor-Computertomografie (MDCT). Material und Methoden: Aus einem Kollektiv von 915 MDCT-Untersuchungen des Thorax wurden 20 Patienten mit Perikardergussen (PE) identifiziert und in die Studie eingeschlossen. An vier fest defnierten Lokalisationen (Rezessus superior, anterior, posterior und apikal) wurden die maximalen Durchmesser der PE von zwei Radiologen unabhangig bestimmt (Abbildung 1). Anschliesend wurden CT-Volumetrien der PE im Konsensusverfahren durchgefuhrt. Mithilfe einer Korrelationsanalyse zwischen den maximalen PE-Diameter der jeweiligen Lokalisationen und den PE-Volumina wurde die Validitat der Messungen bestimmt (R=Pearson-Korrelationskoeffizient). Zur Prufung der Reliabilitat der Messverfahren wurden eine Intraklassenkorrelation (ICC) und eine Bland-Altmann Analyse durchgefuhrt. Ergebnisse: Es konnte fur alle vier Lokalisationen eine gute Validitat der Messmethode nachgewiesen werden (alle R-Werte >0,8 und p-Wert 0,75). Die beste Validitat und Reliabilitat konnte fur die Diametermessungen apikal nachgewiesen werden. Hieraus wurde folgende lineare Gleichung fur die PE-Volumenbestimmung hergeleitet: PE-Volumen=0,296 (ml/cm) x apikaler Diameter (cm) –32ml (Abbildung 2). Schlussfolgerung: In der MDCT kann das Volumen eines PE durch die Anwendung einer einfachen Formel [PE Volumen=0,296 (ml/cm) x apikaler Diameter (cm) –32ml] abgeschatzt werden. In der Klinik ist eine schnelle Erfassung der Ergussvolumina nutzlich, um die hamodynamische Relevanz eines Perikardergusses abzuschatzen, und um dann ggf. bei der Planung einer chirurgischen Drainage oder Perikardiozentese zu helfen.

To prove the feasibility of using Hounsfield attenuation values at MDCT to detect bone bruises related to sacral insufficiency fractures.Twenty-two patients with acute sacrum trauma and no fracture findings at MDCT were included in our prospective study. Two observers independently reviewed CTs regarding visual signs of bone bruises in 132 defined regions of the sacral alae. Interobserver agreement was tested by κ statistics. Subsequently, HU values were obtained in the same regions, and attenuation differences between the two sides were calculated. Validity and reliability were assessed by intraclass correlation coefficient and Bland-Altman analysis. HU differences were subjected to ROC curve analysis to determine sensitivity, specificity, PPV and NPV. MRI served as standard reference.MRI revealed 19 regions with bone bruises and associated sacral insufficiency fractures. HU measurements demonstrated good validity and reliability (r = 0.989). ROC curve analysis exhibited an ideal cutoff value of 35.7 HU density difference between affected and non-affected regions. Visual evaluation revealed moderate agreement (κ = 0.48); diagnostic accuracy was inferior to objective evaluation.Assessment of differences in bone marrow density by HU measurements is an objective and reliable tool for detection of bone bruises associated with occult sacral insufficiency fractures.• Bone bruising is associated with occult sacral insufficiency fractures. • Assessment of differences in bone marrow CT attenuation appears valid and reliable. • Comparative HU measurements of bone marrow allow detection of bone bruises. • Comparative HU measurements have high specificity and negative predictive values. • Comparative HU measurements may make further diagnostic workup with MRI unnecessary.

To investigate the feasibility of diffusion-weighted imaging (DWI) MRI for detecting pulmonary nodules at 1.5 Tesla in comparison with standard multidetector computed tomography (MDCT).Twenty patients with disseminated cancer disease in which MDCT had assured the presence of at least one pulmonary nodule were examined using a respiratory-gated DWI MR-sequence. Grey scale inverted source images and coronal maximum intensity projection (MIP) images were consensually analysed by two experienced radiologists. Size and location of any nodule detected were assessed. Additionally, the readers evaluated each hemithorax for the presence of at least one nodule and applied a four-point conspicuity scale (1-hemithorax definitely affected; 4-hemithorax definitely not affected). MDCT data served as reference.At MDCT, a total of 71 pulmonary noduIes was found (size 3-5mm, n=16; 6-9mm, n=22; ≥10mm, n=33). For the DWI MR-sequence, a sensitivity of 86.4% was calculated for nodules ranging 6-9mm and 97% for nodules ≥10mm. In contrast, only 43.8% of lesions ≤5mm was detected. The separate analysis of each hemithorax for the presence of at least one pulmonary nodule revealed a specificity rate, PPV and NPV of DWI-MR of 92.3%, 96% and 80%, respectively.The presented study is the first to confirm the diagnostic potential of DWI-MR in the detection of solid lung nodules. This technique allows for the detection of nodules ≥6mm with reasonably high sensitivity rates (86%). The observation of false positive findings decreases the accuracy of this approach compared with MDCT.

Purpose To evaluate the technical success and therapeutic effect of superselective embolisation of arteriovenous fistulas in renal allografts. Materials and methods Between 2000 and 2009, 20 patients underwent angiography of 24 AV fistulas (AVF) following percutanous biopsy of the transplanted kidney. Indications for angiography were the diagnosis of AVF by ultrasound and in addition persistent or worsening transplant renal function, or haematuria. Superselective catheterisation of the fistula was performed with a coaxial microcatheter and microcoils were used to occlude the fistula. To assess the short-term effect of embolisation, serum creatinine values were evaluated before embolisation, in the first week after embolisation and after a period of minimum 42 days after the procedure. Results Angiography identified a single AVF in 16 patients and two AVFs in 4 patients. In 19 patients, successful embolisation was achieved without complications. In one patient, a second session was needed to embolise the AVF completely. The mean serum creatinine level of all patients with embolisation dropped significantly (p = 0.0014) from 4.4 mg/dl (range: 1.4–11.6 mg/dl, standard deviation: 3.0) before embolisation to 2.7 mg/dl after embolisation (range: 1.0–7.0 mg, standard deviation: 1.8). No patient showed an increase in serum creatinine. Long-term outcomes of the renal allograft revealed a well-functioning allograft in 19/20 patients. One patient returned to haemodialysis due to acute rejection. Conclusion Superselective transcatheter embolisation is a safe and highly effective treatment for AVFs in renal allografts. Renal function was improved in the majority of patients.

Introduction To investigate the potential correlation of the apparent diffusion coefficient assessed by diffusion-weighted MRI (DWI) and glucose metabolism determined by the standardized uptake value (SUV) at 18F-FDG PET/CT in non-small cell lung cancer (NSCLC). Materials and methods 18F-FDG PET/CT and DWI (TR/TE, 2000/66 ms; b-values, 0 and 500 s/mm(2)) were performed in 41 consecutive patients with histologically verified NSCLC. Analysing the PET-CT data calculation of the mean (SUV(mean)) and maximum (SUV(max)) SUV was performed. By placing a region-of-interest (ROI) encovering the entire tumor mean (ADC(mean)) and minimum ADC (ADC(min)) were determined by two independent radiologists. Results of 18F-FDG PET-CT and DWI were compared on a per-patient basis. For statistical analysis Pearson's correlation coefficient, Bland-Altman and regression analysis were assessed. Results Data analysis revealed a significant inverse correlation of the ADC(min) and SUV(max) (r=-0.46; p=0.032). Testing the correlation of the ADC(min) and SUV(max) for each histological subtype separately revealed that the inverse correlation was good for both adenocarcinomas (r=-0.47; p=0.03) and squamouscell carcinomas (r=-0.71; p=0.002), respectively. No significant correlation was found for the comparison of ADC(min) and SUV(mean) (r=-0.29; p=0.27), ADC(mean) vs. SUV(mean) (r=-0.28; p=0.31) or ADC(mean) vs. SUV(max) (r=-0.33; p=0.23). The κ-value of 0.88 indicated a good agreement between both observers. Conclusion This preliminary study is the first to verify the relation between the SUV and the ADC in NSCLC. The significant inverse correlation of these two quantitative imaging approaches points out the association of metabolic activity and tumor cellularity. Therefore, DWI with ADC measurement might represent a new prognostic marker in NSCLC.

Aim To assess, whether unenhanced balanced steady-state-free precession sequences provide axial thoracic aortic measurements comparable to contrast enhanced magnetic resonance angiography with good intra- and interobserver agreement. Materials and methods Enhanced and unenhanced sequences of the thoracic aorta in 23 consecutive patients were evaluated. Axial thoracic aortic diameters were measured at predefined levels by two independent readers. Pearson's correlation coefficient and Bland–Altman analysis were used to compare enhanced and unenhanced sequences. t-Test was used to determine possible significant differences between the measurements obtained by enhanced and unenhanced sequences. A p-value of less than .05 indicated statistical significance. Intraclass correlation coefficient and Bland–Altman were used for inter- and intraobserver correlation and agreement. Results There was no significant difference in diameter measurements between enhanced and unenhanced sequences (ascending aorta, p = 0.98; descending aorta, p = 0.52). Bland–Altman revealed good agreement between enhanced and unenhanced sequences for ascending (mean bias, −0.01 cm; with 95% limits of agreement, ±0.30 cm) and descending aortic diameters (mean bias, 0.05 cm; with 95% limits of agreement, ±0.30 cm). Inter- and intraobserver agreement (mean bias, less than ±0.15; with 95% limits of agreement, less than ±0.42 cm for all measurements) as well as correlation (r > 0.8 for all measurements) were excellent. Conclusion Unenhanced balanced steady-state-free precession sequences enable rapid and accurate determination of axial thoracic aortic diameters with excellent inter- and intraobserver agreement, but without the risk of contrast media associated side-effects.

PURPOSE: To evaluate the agreement of pulmonary artery diameters assessed with 3D contrast-enhanced MR angiography (CE-MRA) and a 2D balanced steady-state-free precession sequence (bSSFP) in non-stenotic and stenotic pulmonary arteries (PA). METHODS AND MATERIALS: 44 right and left PAs (30 non-stenotic and 14 stenotic) were examined in 23 consecutive patients by performing CE-MRA as well as bSSFP. Two independent readers determined the transverse diameters of the PA. RESULTS: No significant difference in diameter measurements was found between CE-MRA and bSSFP (p = 0.8608 for the stenotic and p = 0.6208 for the non-stenotic PA). Bland-Altman analysis revealed good agreement between CE-MRA and bSSFP for both the non-stenotic (mean bias, 0.07 cm; with 95 % limits of agreement, ± 0.34 cm) and the stenotic (mean bias, 0.05 cm; with 95 % limits of agreement, ± 0.30 cm) PA. CONCLUSION: bSSFP allows rapid and accurate determination of PA diameters without the use of ionizing radiation and the risk of contrast media-associated side-effects.

To assess radiofrequency (RF)-induced heating of fixed orthodontic appliances during acquisition of three different sequences in magnetic resonance imaging (MRI) at 3 Tesla.Ten commonly used fixed orthodontic appliances were investigated utilizing a phantom head and simulating the in vivo intraoral situation. A 3 Tesla MRI system (Intera, Philips Medical Systems, Best, The Netherlands) was used to acquire T1w spin-echo (T1 SE), T1w turbo spin-echo (T1 TSE) and T1w gradient-echo (T1 GRE) sequences in axial orientation. Continuous temperature measurement was performed with a dedicated four channel fluoroptic thermometry system. For each orthodontic appliance temperature probes were placed at three predefined sites in order to perform temperature measurements during MR imaging. The fourth temperature probe was fixed to the neck of the phantom head and served as the reference. Mean temperature alterations were determined for all appliances.Temperature elevations ranged from -0.3 degrees C to 0.2 degrees C and were negligible for all orthodontic appliances investigated. There was no difference in mean temperature alteration for any of the three imaging sequences.Based on the data of our experimental study the radiofrequency-induced heating of orthodontic brackets during high field MRI at 3 Tesla can be categorized as negligibly low. Even the clinical routine examination of the head at 3 Tesla using high-energetic pulse sequences can be applied without hesitation in patients with fixed orthodontic appliances.

PURPOSE: Experimental evaluation of image quality of the upper urinary tract in MR urography (MRU) at 1.5 and 3 Tesla in a porcine model. MATERIALS AND METHODS: In this study four healthy domestic pigs, weighing between 71 and 80 kg (mean 73.6 kg), were examined with a standard T1w 3D-GRE and a high-resolution (HR) T1w 3D-GRE sequence at 1.5 and 3 Tesla. Additionally, at 3 Tesla both sequences were performed with parallel imaging (SENSE factor 2). The MR urographic scans were performed after intravenous injection of gadolinium-DTPA (0.1 mmol/kg body weight (bw)) and low-dose furosemide (0.1 mg/kg bw). Image evaluation was performed by two independent radiologists blinded to sequence parameters and field strength. Image analysis included grading of image quality of the segmented collecting system based on a five-point grading scale regarding anatomical depiction and artifacts observed (1: the majority of the segment (>50%) was not depicted or was obscured by major artifacts; 5: the segment was visualized without artifacts and had sharply defined borders). Signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were determined. Statistical analysis included kappa-statistics, Wilcoxon and paired student t-test. RESULTS: The mean scores for MR urographies at 1.5 Tesla were 2.83 for the 3D-GRE and 3.48 for the HR3D-GRE sequence. Significantly higher values were determined using the corresponding sequences at 3 Tesla, averaging 3.19 for the 3D-GRE (p = 0.047) and 3.92 for the HR3D-GRE (p = 0,023) sequence. Delineation of the pelvicaliceal system was rated significantly higher at 3 Tesla compared to 1.5 Tesla (3D-GRE: p = 0.015; HR3D-GRE: p = 0.006). At 3 Tesla the mean SNR and CNR were significantly higher (p < 0.05). A kappa of 0.67 indicated good interobserver agreement. CONCLUSION: In an experimental setup, MR urography at 3 Tesla allowed for significantly higher image quality and SNR compared to 1.5 Tesla, particularly for the visualization of the pelvicaliceal system.

Ziele: Evaluation des Stellenwertes der diffusionsgewichteten echoplanaren (DW-EPI) Bildgebung zur Differenzierung unterschiedlicher histologischer Subtypen des Bronchialkarzinoms mittels ADC-Messung (apparent-diffusion-coefficient) bei 1.5 Tesla. Methode: Es wurden 15 Patienten mit histologisch gesichertem Bronchialkarzinom (Adenokarzinom: n=6; Plattenepithelkarzinom: n=5; kleinzelliges Bronchialkarzinom: n=4) unter Verwendung einer DW-EPI Sequenz (TR/TE: 2000/66ms; FOV: 425×298mm; Matrix: 256; Schichtdicke: 8mm; b-Faktor: 0 und 500s/mm2) untersucht. Alle Messungen erfolgten vor Einleitung einer Chemotherapie oder Radiatio. Mithilfe des Software-tools „MRIcro“ (Chris Rorden, University of Nottingham, Grosbritannien) erfolgte die Berechnung der mittleren ADC-Werte basierend auf einer den gesamten Tumor einschliesenden Region-of-interest (ROI). Zusatzlich wurde der mittlere ADC-Wert des Liquor cerebrospinalis berechnet. Die statistische Analyse beinhaltete den zweiseitigen Student's-t-Test, hierbei wurde ein p-Wert

Ziele: Erfassung der Bedeutung der diffusionsgewichteten Bildgebung mit Unterdruckung des Hintergrundsignals (DWIBS) in der Detektion pulmonaler Noduli bei 1.5 Tesla. Methode: Es wurden 18 konsekutive Patienten mit disseminierter Tumorerkrankung (Bronchialkarzinom: 8 Patienten; Pulmonale Metastasen: 10 Patienten), bei denen computertomographisch Lungenrundherde nachgewiesen wurden, mittels einer diffusionsgewichteten Sequenz mit Unterdruckung des Hintergrundsignals (DWIBS) (TR/TE: 2700/65ms; TI: 180ms; FOV: 425×278mm; b-Faktor: 0 und 500s/mm2; Messzeit: 119s) unter Verwendung eines Atemtriggers bei 1,5 Tesla untersucht. Aus allen Datensatzen wurden Maximum-Intensitats-Projektionen in 5° Intervall entlang der Korperlangsachse rekonstruiert. Die Auswertung der anonymisierten Bilder erfolgte durch zwei Radiologen im Konsensus. Lage und Grose der detektierten Noduli wurden notiert. Als Goldstandard dienten die axialen CT-Bilder. Ergebnis: Die Analyse der CT-Datensatze der 18 Patienten zeigte insgesamt 62 pulmonale Herde mit einem Diameter von 3mm bis 9,2cm (Diameter 3–5mm: n=16; 6–10mm: n=19; >10mm: n=27). Fur die DWIBS-MRT fanden sich Sensitivitaten von 84,2% fur Noduli von 6–10mm und 96,3% fur Herde >10mm. Kleinere Lasionen 6mm mit einer der MDCT vergleichbaren Sensitivitat (>90%). Korrespondierender Autor: Schreiter D Universitatsklinikum Hamburg-Eppendorf, Diagnostikzentrum; Klinik und Poliklinik fur Diagnostische und Interventionelle Radiologie, Martinistr. 52, 20246 Hamburg E-Mail: d.schreiter@uke.uni-hamburg.de

Ziele: Prospektive Analyse des Stellenwertes sekundarer Rekonstruktionen in der Detektion pulmonaler Noduli am 64-Zeilen CT-Scanner unter besonderer Berucksichtigung der Befundsicherheit und Erfahrung des Auswerters. Methode: Drei Radiologen (1; 2 und 7 Jahre Erfahrung) evaluierten die CT-Datensatze von 25 Patienten mit pulmonalen Noduli. Axiale Standard-CT-Schichten (SR) (Schichtdicke 5mm; Inkrement 5mm), Maximum-Intensitats-Projektionen (MIP) und Volume-Rendering-Bilder (VR) (Schichtdicke 10mm; Inkrement 5mm) wurden in zufalliger Reihenfolge analysiert. Fur jeden Datensatz wurden Lokalisation des Nodulus und Befunddauer erfasst. Anhand einer 3-Punkte-Skala wurde die subjektive Befundsicherheit fur jede Technik ermittelt (1=Nodulus sicher detektiert; 2=Befund nicht sicher als Nodulus zu interpretieren; 3=Befund eher nicht einem Nodulus zuzuordnen). Als Goldstandard wurden 1mm Schichtbilder im Konsensus ausgewertet. Die statistische Analyse beinhaltete den Multi-Rater-Kappa sowie Wilcoxon-Test. Ergebnis: Die Analyse der CT-Datensatze der 25 Patienten umfasste insgesamt 115 pulmonale Noduli (Diameter 1–4mm: 57 Noduli; 5–9mm: 45 Noduli; >10mm: 13 Noduli). Mithilfe der MIP-Bilder wurden signifikant mehr kleine Noduli (

The purpose of the study was to investigate the value of diffusion-weighted (DW) echo-planar imaging (EPI) for quantifying physiological changes of the parotid gland before and after gustatory stimulation in patients suffering from acute or chronic recurrent inflammation in comparison with healthy volunteers. Using a DW-EPI sequence at 1.5 T, parotid glands of 19 consecutive patients with acute (n=14) and chronic (n=5) inflammation of parotid glands and 52 healthy volunteers were examined. Magnetic-resonance (MR) images were obtained before and after gustatory stimulation with 5 cc of lemon juice. In volunteers mean ADC values of 1.14 x 10(-3) mm(2)/s before and 1.2 x 10(-3) mm(2)/s after gustatory stimulation were observed. In acute inflammation ADC values were higher before [1.22 x 10(-3) mm(2)/s (p=0.006)] and after stimulation [1.32 x 10(-3) mm(2)/s (p

Purpose: To retrospectively analyze the reliability of opacification and image quality of a modified MDCTU examination protocol using furosemide and an individual acquisition delay by low-dose test images Materials and Methods: Excretory phase images obtained from 4-row and 16-row MSCTU examinations in 103 patients (69 men, 34 women) were independently reviewed by two radiologists. MDCTUs were performed by using a low-dose furosemide iv injection. No fixed delay for urographic image acquisition was applied. Urographic timing was individually adjusted by performing low-dose test images of the distal ureters to display their current opacification. Image analysis included grading of opacification and image quality of the segmented collecting system. Average urographic delay was calculated. Stratified comparisons of mean scores were assessed. Interobserver kappa values were calculated. Results: Calculated median scan delay for patients with normal creatine levels (n = 92) was 420 sec (mean 453 sec; SD, 121 sec). The median number of acquired test images was 2 (range 1-6 images). The analysis of opacification demonstrated that 97% of the ICS, 89% of the proximal, 86% of the middle, and 81% of the distal ureter segments showed opacification greater than 90%. 7.8% of the distal ureteral segments could not be visualized. Statistics did not show significant differences of opacification between proximal, middle, and distal ureteral segments (P > 0.05). Overall image quality of MSCTU showed to be high when latest test images indicated homogeneous bilateral contrasted ureters (Pearson correlation coefficient r= 0.81). Interobserver κ values were 0.8 and 0.78. Conclusion: Furosemide and scan delay timing by means of test images for MDCTU proved to be a reliable procedure to reach improved opacification of the upper urinary tract. It features the individual adaption of MDCTU to the excretory rate of the kidneys.

To evaluate two MR imaging sequences for the detection of artificial pulmonary nodules inside porcine lung explants. 67 agarose nodules ranging 3-20 mm were injected into ten porcine lungs within a dedicated chest phantom. The signal on T1-weighted images and radiopacity were adjusted by adding 0.125 mmol/l Gd-DTPA and 1.5 g/l of iodine. A T1-weighted three-dimensional gradient-echo (T1-3D-GRE; TR/TE:3.3/1.1 ms, slice:8 mm, flip-angle:10 degrees ) and a T2-weighted half-Fourier fast-spin echo sequence (T2-HF-FSE; TR/TE:2000/66 ms, slice:7 mm, flip-angle:90 degrees ) were applied in axial orientation using a 3-T system (Intera, Philips Medical Systems, Best, The Netherlands), followed by CT (16x0.5 mm) as reference. Nodule sizes and locations were assessed by three blinded observers. In nodules of10 mm, sensitivity was 100% using 3D-GRE-MRI and 94% using the HF-FSE sequence. For nodules 6-10 mm, the sensitivity of MRI was lower than with CT (3D-GRE:92%; T2-HF-FSE:83%). In lesions smaller than 5 mm, the sensitivity declined to 80% (3D-GRE) and 53% (HF-FSE). Small lesion diameters were overestimated with both sequences, particularly with HF-FSE. This study confirms the feasibility of 3 T-MRI for lung nodule detection. In lesions greater than 5 mm, the sensitivity of the 3D-GRE sequence approximated CT (90%), while sensitivity and PPV with the HF-FSE sequence were slightly inferior.

Important parameters, that define the physical properties of an emulsion, are the concentrations of the constituents. In the case of a continuous production of emulsions an exact and fast control of the fractions is essential to ensure a constant product quality. Whereas the method of sample drying, weighing and chemical analysis is too slow for an online product control, the dispersed phase fraction determinition by density only works for two-component-systems. For the purpose of more practical emulsions with possible variations in both, the dispersed phase fraction and the salt content, in this work dielectric spectroscopy in combination with principal component analysis is studied. Introduction The properties of an emulsion are strongly dependent on the concentratations of constituents. As an example, the rheological and the sensory properties depend on the fraction of the dispersed phase (here the oil phase, of an oil-in-water emulsion). Emulsions in practice often consist of more than two chemical species. It is therefore not sufficient to chracterise the emulsions by the measurement of its dielectric properties at one frequency. For a sufficient characterisation the measurement of the dielectric constant over a frequency range is necessary, yielding a large data set, difficult to analyse. One possible method for its analysis is the principal factor analysis, which is a mathematical-statistical technique [1]. It was first used in the behavioral sciences

We sought to evaluate intraindividually 3 different preparation protocols for achieving improved opacification and anatomic depiction of the upper urinary tract in multisclice computed tomography urography (MSCTU) using a porcine model.MSCTU was performed in 8 healthy pigs. Each animal underwent 3 MSCT urographies using 3 different preparations before the injection of contrast material: A, intravenous (iv) saline (250 mL); B, iv low-dose furosemide (0.1 mg/kg); and C, iv saline (250 mL) plus iv low-dose furosemide (0.1 mg/kg). Image analysis was performed blinded to the applied protocols and included the evaluation of the opacification and anatomic depiction of the upper urinary tract by means of graded scales. Ureteral distension was determined and density was measured within the collecting system.Furosemide significantly improved both mean opacification scores and mean scores of anatomic depiction compared with the exclusive infusion of saline for MSCTU. There was no significant difference between the application of furosemide and the combination of furosemide plus saline. A significant increase of 25-26% for ureteral distension was found when furosemide was applied. Significant lower mean attenuation values (Hounsfield units) and standard deviation were found within the opacified urine for diuretic-enhanced MSCTU.Low-dose furosemide injection is superior to saline infusion for achieving optimal enhancement in MSCTU. It is not necessary to combine furosemide and saline infusion. In MSCTU, low-dose furosemide is a simple add-on simplifying image acquisition timing and removing the need for abdominal compression devices.

Dielectric properties of water-in-oil emulsions, oil in water emulsions and limestone-in-water suspensions have been measured at 2.45 GHz by an open-ended coaxial-line probe. The results were compared to various equations for the dielectric properties of mixtures. The equation by Fricke and Mudgett describes best the behavior of oil-in-water emulsions and limestone in water suspensions. For water-in-oil emulsions the equation by Lichtenecker and Rother gives the best results.

In February, 2010, a 45-year-old woman weighing 220 kg (body-mass index 68 kg/m2) was referred to our institution after a 3-month history of progressive abdominal distension without fever or night sweats or other complaints (appendix). Medical and family history was otherwise unremarkable, with her last gynaecological examination 2 years previously. Sonog raphy of the abdomen showed ascites but no other pathological changes. Repeated paracenteses drained 32 L of serous, exudative fl uid over 16 days. Cytology detected papillary formation of epithelial cells with psammoma bodies suggestive of a serous tumour of the ovaries. Sonography of the pelvis and abdomen and open fi eld MRI (patient’s weight and circumference precluded CT) showed large bilateral cystic pelvic tumours, abundant ascites, but no further pathological changes in the abdomen (fi gure A). Blood tests were normal except for a raised CA125 of 967 kU/L (normal range, 0–35). During an explorative laparotomy an additional 24 L of ascitic fl uid was drained. The pelvic tumours turned out to be enlarged ovaries, measuring 18 cm and 25 cm (appendix), without further macroscopic peritoneal tumour spread. Frozen section analysis suggested borderline ovarian tumour, and surgical staging with hysterectomy, bilateral salpingo-oophorectomy, omentectomy, appendectomy, and peritoneal biopsies was done. Defi nite histology showed adenofi broma of both ovaries with transition to serous borderline ovarian tumour, and non-invasive implants of the omentum. Unusually, extensive lymph atic vascular invasion was seen in the fallopian tube, the myometrium, and the wall of the appendix (fi gure B). These results were confi rmed by independent path ologists, and led to classifi cation of