Superparamagnetic Iron Oxide Enhanced MR Imaging: Influence of Hepatic Dysfunction in Cirrhotic Patients

PURPOSE: To determine the influence of liver dysfunction on the detection of focal hepatic nodules, and to investigate the loss of signal intensity of hepatic parenchyma occurring after superparamagnetic iron oxide (S-PIO)-induced contrast enhancement in patients with liver cirrhosis. MATERIALS AND METHODS: In 68 patients with liver cirrhosis, we evaluated MR images before and after the administration of SPIO. Clinical information and laboratory data indicated that the liver was normal in ten patients (nine hemangiomas and one hepatic cyst), while Child's A was diagnosed in 25 cases [22 of which were hepatocellular carcinomas (HCCs)], Child's B in 15 (11 HCCs), and Child's C in 18 (10 HCCs). Before and after SPIO administration, conventional T2-weighted spin-echo, respiratory-triggered T2-weighted turbo spin-echo, and breathhold T2-weighted turbo spin-echo images were obtained. After the administration of SPIO, degrees of liver dysfunction and laboratory data were correlated with reductions in signal intensity of the liver, and, in addition, the state of hepatic dysfunction was corelated with inhomogeneous parenchymal change and lesion conspicuity. RESULTS: After the administration of SPIO, percentage signal loss in liver parenchyma was significantly higher on conventional T2-weighted spin-echo images than on T2-weighted turbo spin-echo and breathhold T2-weighted turbo spin-echo (p < 0.05). There was significant correlation between degree of liver dysfunction and of signal loss (p < 0.05), while percentage signal loss of the liver was lower in the Child's C group than in the other three. In addition, there was close correlation between percentage signal loss and laboratory data such as albumin and total bilirubin levels, and prothrombin time (p < 0.05). Qualitative analysis showed that inhomogeneous enhancement due to fibrous septa and a regenerative nodule occurred more often in the Child's B and Child's C group than in the normal and Child's A group (p < 0.0001). In terms of legion conspicuity, there was no statistically significant difference between the groups (p > 0.05). CONCLUSION: SPIO uptake by hepatic parenchyma correlated closely with Child's degree of liver cirrhosis and laboratory data such as albumin and total bilirubin levels, and prothrombin time. In the Child's B and Child's C group, SPIO-enhanced MR imaging revealed inhomogeneous hepatic parenchyma, but the pattern observed did not affect the detection of hepatic nodules.