Purpose: The purpose of our preliminary study was to evaluate the feasibility of a new technique for the perfusion weighted color display of the density of lung parenchyma derived from multi-slice CT (MSCT) data sets of clinical routine examinations for visualization of pulmonary embolism (PE). Materials and Methods: Imaging of patients with suspected PE was performed on a commercially available MSCT (Somatom Volume Zoom; Siemens, Forchheim, Germany) after intravenous application of 120 cc of contrast-medium using a power injector. Scan parameters were 140 kV and 100 mAs, using a thin collimation of 4 ” 1 mm and a table speed of 7 mm (pitch: 1.75). Derived from thin collimation axial slices (slice thickness eff. 1.25 mm, reconstruction increment 0.8 mm), a new image processing technique was deployed. Based on these source images, an automated 3D-segmentation of the lungs was performed followed by threshold based extraction of major airways and vascular structures. The filtered volume data were color encoded and finally overlayed onto the original CT images. This color encoded display of parenchymal density distribution of the lungs was shown in axial, coronal and sagittal plane orientation. In four patients with excluded PE as well as in two patients with proven PE this new technique was performed. Results: In the four patients that were considered negative regarding PE on MSCT, lung densitometry showed a homogeneous distribution of color encoded densities without circumscribed decreased or increased areas, beside the usually present gravity-dependent gradient in ventro-dorsal direction. In the two patients with proven PE, low density values on perfu-sion weighted color maps were found distally to the occluded pulmonary arteries. Conclusions: Our initial experience indicates that lung densitometry with an optimized display of the density distribution within the lung parenchyma may provide additional information in patients with suspected or proven PE. However, a comparison with ventilation/perfusion scintigraphy and a larger number of patients are necessary for the full clinical evaluation of this new functional imaging methodology. Farbkodierte Darstellung des Lungenparenchyms bei ver-muteter Lungenembolie mittels Mehrschicht-Spiral-CT. Ein-leitung: Ziel unserer Studie war die Erprobung einer neuen farbkodierten Darstellung des Lungenparenchyms an Patienten mit Verdacht auf Lungenembolie (LE) anhand von Mehrschicht-Spiral CT (MSCT) Datensätzen aus der klinischen Routine. Material und Methode: Die Untersuchungen bei klinisch vermuteter LE wurden an einem MSCT (Somatom Volume Zoom; Siemens, Forchheim) nach intravenöser Gabe von 120 ml nichtionischem Kontrastmittels über einen Power-Injektor durchgeführt. Die Acquisitionsparameter waren 140 kV und 100 mAs mit dünner Kollimation (4 ” 1 mm) und einem Tischvorschub von 7 mm (Pitch: 1,75). Anhand dünner axialer Primärschichten (Eff. Schichtdicke: 1,25 mm, Rekonstruktionsinkrement: 0,8 mm) wurde eine neue Nachverarbeitungstechnik angewandt. An-hand der Quellschichten e...

The aim of this study was to work out the cross-sectional imaging characteristics of desmoplastic fibroma (DF). In 3 patients with histologically proven DF, the imaging characteristics obtained with cross-sectional techniques were reviewed retrospectively. Radiographs and CT scans were available in all patients, and plain and contrast-enhanced MR examinations in 2 patients. Compared with conventional radiographs, CT allowed more accurate assessment of the extent of bone destruction including cortical breakthrough and articular invasion. Intramedullary tumor growth and soft tissue extension was best detected with MRI. Apart from heterogeneity on MR images, DF displayed nonspecific low signal intensity on unenhanced T1-weighted images and an intermediate to high signal intensity including areas of low intensity on T2-weighted images. Desmoplastic fibroma showed a distinct, inhomogeneous gadolinium enhancement. Although cross-sectional imaging features of DF are nonspecific, some MR characteristics, such as inhomogeneous contrast enhancement and the presence of low-intensity regions on T2-weighted images, are helpful in determining the differential diagnosis. Cross-sectional imaging of DF is useful for local staging of the tumor because it provides valuable information about the extent of bone destruction as well as medullary and extraosseous spread.

Recurrent variceal bleeding due to liver cirrhosis led to treatment with a transjugular intrahepatic portosystemic shunt (TIPS) in a pregnant woman at 20 weeks' gestation. Fetal radiation exposure was estimated to be less than 10 mSv. The use of a graduated catheter allowed measurement of field size and reliable determination of the patient's entrance dose. Radiation exposure of an approximated fetal dosage of 5.2 mSv did not justify abortion for medical reasons. Therefore, TIPS procedure is not generally contraindicated during pregnancy itself. TIPS placement may be a therapeutic option related to the severity of the underlying maternal disease, after radiation exposure of the fetus has been estimated.

pRCT presents a quite unique CT appearance similar to its gross pathology.

Panoramic ultrasound offers nearly complete visualization of the spinal canal in children on one single extended field of view image. The conus medullaris level and the tip of the dural sac can easily be localized.