Superimposed peripheral pulmonary vasculature in anthropomorphic chest phantoms.

RATIONALE AND OBJECTIVES: Comparative radiologic studies often involve the use of phantoms. However, in most chest phantoms, the lack of sufficient peripheral vessels results in unrealistic images. This can impair the reliability of conclusions drawn from the studies performed. The authors present a method of improving the simulation of the peripheral pulmonary vasculature in anthropomorphic chest phantoms. METHODS: The appearance of peripheral vessels was simulated using red lead painted on transparent foils. Several of the foils were taped to the back of the phantom to give the impression of superimposed blood vessels. RESULTS: Subjectively, a more realistic appearance of peripheral vasculature was obtained in the radiograph. CONCLUSIONS: Our method improves the quality of widely available anthropomorphic chest phantoms, and the modification is easily implemented. However, the use of lead limits the modified phantom to comparative studies with constant exposure voltage.

[Magnetic resonance cholangiopancreatography: sensitive and specific diagnostic method for suspected choledolithiasis]. / Magnetische-resonantiecholangiopancreatografie: sensitieve en specifieke onderzoeksmethode bij vermoeden van choledocholithiasis.

OBJECTIVE: To evaluate the role of magnetic resonance pancreaticography (MRCP) in the diagnostic process of common bile duct stones. DESIGN: Retrospective. METHOD: All 27 MRCPs performed in the period December 1997-December 1998 in the Deventer Hospital, the Netherlands, were evaluated using chart examination. The group comprised 11 males and 16 females with an average age of 57 years (SD 3.2) with anamnestic or biochemical cholestasis. If at MRCP stones were diagnosed, endoscopic retrograde cholangiopancreaticography (ERCP) was performed. If MRCP was without abnormalities, no further diagnostic procedures were performed. The findings at MRCP were compared with those at ERCP and with the clinical course. The MRCP examinations were performed on a 1.5 Tesla MR unit. RESULTS: In 16 patients MRCP was performed before laparoscopic cholecystectomy and in 5 there after. In 5 MRCP was performed to rule out a biliary cause of acute pancreatitis and in 1 patient because of an elevated alkaline phophatase after laparotomy for an abdominal stab injury. There was one false-positive MRCP result and no false-negative ones. Accordingly, the sensitivity of MRCP for choledocholithiasis was 100% and the specificity 95%.