MR CHOLANGIOPANCREATOGRAPHY USING ON OPEN , LOW MAGNETIC-FIELD OF 0.2TESLA - EARLY CLINICAL-RESULTS AND COMPARISON WITH A HIGHER MAGNETIC-FIELD (1.5 TESLA) AND WITH ERCP

To evaluate MR cholangio-pancreatography (MRCP) using an open low magn etic field apparatus in normals and in patients with mechanical choles tasis. Methods: MRCP was performed on five normals and on 30 patients, using both an 0.2 Tesla and 1.5 Tesla apparatus. With the low field s ystem, rapid acquisition by relaxation enhancement was used, for the h igh field system, half Fourier acquisition single shot turbo spin-echo sequences were used. In all patients, sonography and ERCP or PTC was performed; 23 underwent surgery. Results: In all normals it was possib le to show the bile duct, hepatic duct, gall bladder and intrahepatic ducts of the first order. Using the high field system, second order du cts could be shown and sometimes third order ducts. In the patients, M RCP, using either system, demonstrated all 21 obstructive sites due to tumours or stenoses. Stones were shown in 69% by the low field system and in 88% by the high field system. Conclusion: MRCP can be successf ully carried out using the low field system. In the presence of mechan ical cholestasis, image quality is adequate for the localisation of st enoses and occlusions, and, using an open magnet, is suitable for plan ning further intervention.