Delineation of liver necrosis using double contrast-enhanced MRI

The purpose of this study was to demonstrate the potential usefulness of the combination of gadolinium and dysprosium to enhance the different between normal and necrotic liver tissue. Small regions of acute necrosis were induced by injecting 200-300 microliters of 95% alcohol into the liver of 26 rats. MRI was performed 24 hours after necrosis induction, before and immediately after injection of one or both contrast agents. Using a mixed T1/T2-weighted sequence, the signal intensity of (SI) of the normal liver was reduced by 70%, whereas the necrotic regions had more than a 50% increase in SI after double contrast. The region that was enhanced corresponded largely with the region of necrosis as observed postmortem. The lesion size, when identified, was largely underestimated using either of the agents along, albeit using the common pulse sequences. The double contrast effect of simultaneous administration of gadolinium and dysprosium allows accurate delineation of liver necrosis.