Primitive neuroectodermal tumours (PNET) are highly malignant, undifferentiated supratentorial neoplasms arising from germinal matrix cells of the primitive neural tube. PNET occur primarily in young children; they are extremely rare in adults. PNET frequently seed within the central nervous system and may be multicentric at the time of diagnosis. Previous reports of the neuroradiological findings refer solely to PNET in children. We describe the computed tomography (CT) and magnetic resonance imaging (MRI) appearances in five adult patients with pathologically proven PNET. In our series, PNET were mostly seen as rather large, heterogeneous masses with cystic and necrotic areas, intratumoral haemorrhage and focal calcification. The prominent contrast enhancement on both CT and MRI scans reflects the increased vascularity of PNET.

Routine use of intraoperative cholangiography during laparoscopic cholecystectomy is still widely advocated and standard in many departments; however, it is controversial. We have developed a new diagnostic strategy for the detection of bile duct stones. The concept is based on an ultrasound examination and on screening for the presence of six risk indicators of choledocholithiasis. A total of 120 patients undergoing laparoscopic cholecystectomy were prospectively screened for the presence of these six risk indicators: history of jaundice, history of pancreatitis, hyperbilirubinemia, hyperamylasemia, dilated bile duct, and unclear ultrasound findings. The sensitivity of ultrasound and intraoperative cholangiography in diagnosing bile duct stones was also evaluated. For the detection of bile duct stones, the sensitivity was 77% for ultrasound and 100% for intraoperative cholangiography. Twenty percent of all patients had at least one risk indicator. The presence of a risk indicator correlated significantly with the presence of choledocholithiasis (P < 0.01, chi-square test). The negative predictive value of the total set of risk indicators was 100%. Following our diagnostic concept, we would have avoided 80% of intraoperative cholangiographies without missing a stone in the bile duct. This study lends further support to the view that routine use of intraoperative cholangiography is not necessary.

A study was performed to determine the visualization of the transjugular intrahepatic portosystemic stent shunt (TIPSS) and the detection of stenosis by the use of a capillary transversing signal enhancer. In 37 patients 37 colour-coded duplex sonographies were performed before and after intravenous injection of the ultrasound signal enhancer Levovist (Schering, Berlin). The examinations were evaluated using a four-category score. Special attention was paid to the detection of stenoses in the TIPSS. Transjugular portal venograms of the same day were used as gold standard. The use of Levovist provided better colour and flow signals for the portal vein end of the shunt in only 9 of 37 sonograms and for the hepatic vein end of the shunt in 37 of 39 sonograms. Eleven of 13 stenoses requiring reintervention in portal venography could be correctly identified with signal enhancer. Eleven of these 13 stenoses were located in the hepatic vein end of the shunt. Ultrasound signal enhancer can significantly improve the sonomorphological visualization especially of the hepatic vein end of TIPSS in colour-coded duplex sonography. Stenoses which usually occur in the hepatic vein end of the shunt may be better detected.