MRI findings of experimentally induced hepatic infarction: Correlation between changes of MRI findings of liver parenchyma and capsule with time lapse and histopathology

We experimentally induced hepatic infarction in rabbit to evaluate MR findings of liver parenchyma and capsule and its changes with time and to confirm the capsular structure correlating with its histologic findings. After ligation of hepatic artery, vein and duct of right inferior posterior lobe of liver, T1, T2 weighted and enhanced T1 weighted images were obtained at several time intervals. Histologic samples were taken of two rabbits or more at each time intervals. During the first several days, the signal intensity of the ischemic necrosis showed strong high signal intensity relative to normal liver on both T1 and T2 weighted images. After 2 weeks , however, the necrotic areas gradually changed to isointensity or low signal intensity. Capsule structure was observed as slightly high signal intensity compare to ischemic areas on both enhanced T1 and T2 weighted images in six cases, and five cases of 12, retrospectively. From the first day, homogeneous coagulation necrosis without hemorrhage or liquefaction was observed. Fibrous thickening with rich vascularity was observed along the surface of the necrosis area after two weeks. During the first several days, the signal intensity of the ischemic necrosis showed strong high signal intensity on both T1 and T2 weighted images and gradually changed to isointensity or low signal intensity. Liver capsule was shown and slightly high signal intensity along the surface of the necrosis area and could be explained by fibrous thickening of the liver capsule and rich vascularity within in it