OBJECTIVE To explore the MR characteristics following lipiodol retention in rabbit liver and to evaluate the sensitivity of CT (CT value 〉400 HU) and MR in displaying the hepatic degeneration and necrosis following...OBJECTIVE To explore the MR characteristics following lipiodol retention in rabbit liver and to evaluate the sensitivity of CT (CT value 〉400 HU) and MR in displaying the hepatic degeneration and necrosis following embolization. METHODS Thirty-two rabbits were randomly divided into 3 groups. In the control group (n=8), 2 ml of normal saline was injected into the right branch of the portal vein. In the first experimental group(n= 12), 4 ml of lipiodol emulsion was injected into the main portal vein. In the second experimental group (n= 12), 2 ml of lipiodol emulsion was injected into the right branch of the portal vein. CT and MR images were obtained before and after surgery in each group. The histopathologic condition was determined for all liver tissue specimens. RESULTS In the control group, CT and MR did not show any significant changes in the livers after surgery. After the operations in the experimental groups, the regional CT attenuation was 601±101 HU in the largest slice, which had no abnormal signals on T1Wl and T2Wl. In the first group, histologic examinations showed there were concentrated lipiodol droplets around the portal areas. In the second group, serious degeneration and necrosis in the right hepatic lobe occurred in 9 rabbits. T1Wl displayed homogenous or non-homogenous low signals and T2Wl mainly displayed a high signal. However, these pathologic changes did not appear on CT scanning due to high attenuation of the lipiodol. CONCLUSION There were no remarkable hepatic changes on MR in rabbits following good retention of the formulated lipiodol emulsion mixture of lipiodol and urografin(CT value 〉 400 HU). MR displayed serious degeneration and necrosis of the liver following embolization.展开更多
文摘OBJECTIVE To explore the MR characteristics following lipiodol retention in rabbit liver and to evaluate the sensitivity of CT (CT value 〉400 HU) and MR in displaying the hepatic degeneration and necrosis following embolization. METHODS Thirty-two rabbits were randomly divided into 3 groups. In the control group (n=8), 2 ml of normal saline was injected into the right branch of the portal vein. In the first experimental group(n= 12), 4 ml of lipiodol emulsion was injected into the main portal vein. In the second experimental group (n= 12), 2 ml of lipiodol emulsion was injected into the right branch of the portal vein. CT and MR images were obtained before and after surgery in each group. The histopathologic condition was determined for all liver tissue specimens. RESULTS In the control group, CT and MR did not show any significant changes in the livers after surgery. After the operations in the experimental groups, the regional CT attenuation was 601±101 HU in the largest slice, which had no abnormal signals on T1Wl and T2Wl. In the first group, histologic examinations showed there were concentrated lipiodol droplets around the portal areas. In the second group, serious degeneration and necrosis in the right hepatic lobe occurred in 9 rabbits. T1Wl displayed homogenous or non-homogenous low signals and T2Wl mainly displayed a high signal. However, these pathologic changes did not appear on CT scanning due to high attenuation of the lipiodol. CONCLUSION There were no remarkable hepatic changes on MR in rabbits following good retention of the formulated lipiodol emulsion mixture of lipiodol and urografin(CT value 〉 400 HU). MR displayed serious degeneration and necrosis of the liver following embolization.