Intrahepatic calculi: imaging by MR.

The magnetic resonance (MR) examinations of six patients with intrahepatic calculi were reviewed retrospectively to 1) determine the ability of MR to demonstrate intrahepatic calculi and 2) assess the MR appearance of the stones. In five out of six cases, MRI demonstrated intrahepatic calculi. In three cases, stones exhibited a low intensity signal on the different spin echo (SE) sequences, as previously described by in vitro and in vivo studies. However in two other cases, a significant signal with short T1 and relatively long T2 relaxation times was noticed. These different features are discussed in relation to chemical and physical differences in intrahepatic calculi and compared with variable CT attenuation values of stones. MRI seems to provide complementary information concerning intrahepatic calculi.