CT灌注成像及MR扩散加权成像评价兔肝纤维化的价值

The value of CT perfusion and MR diffusion weighted imaging in diagnosis of liver fibrosis in rabbits

目的探讨双源CT灌注成像及MR扩散加权成像评价兔肝纤维化分期的价值。方法新西兰大白兔60只进行四氯化碳腹腔注射建立肝纤维化模型(实验组),新西兰大白兔10只进行腹腔注射生理盐水建立对照模型(对照组)。行双源CT灌注成像及MR扩散加权成像,比较不同肝纤维化分期时CT灌注参数,包括门静脉灌注量(portal venous perfusion,PVP)、肝动脉灌注指数(hepatic perfusion index,HPI)和MRI扩散加权成像测量ADCperf值的变化,分析各参数与纤维化分期的关系。结果 HPI随着肝纤维化程度的增加逐渐升高,PVP随着肝纤维化程度的增加而减低。PVP与肝纤维化的严重程度呈负相关(r=-0.589),HPI与肝纤维化的严重程度呈正相关(r=0.652)。ROC曲线显示,PVP预测S2期及以上肝纤维化时诊断效能最佳,HPI预测S2期及以上肝纤维化时诊断效能最佳。随着肝纤维化程度加重,ADCperf值依次降低,差异有统计学意义(P<0.01),ADCperf预测S2期及以上肝纤维化时曲线下面积最大。肝脏ADCperf值与肝纤维化的严重程度呈负相关(r=-0.720)。结论HPI、PVP、ADCperf能够反映肝纤维化各期灌注变化。

Objective To explore the value of evaluating the stage of hepatic fibrosis using dual source CT perfusion and multi-b value diffusion weighted imaging. Methods 70 New Zealand white rabbits,the experimental group of 60 rabbits,liver fibrosis model was established by intraperitoneal injection of carbon tetrachloride,10 rabbits in the control group,intraperitoneal injection of saline. Both groups of rabbits were undergone perfusion imaging with dual source CT and multi-b value diffusion weighted imaging. CT perfusion parameters,including portal venous perfusion（ PVP） and hepatic perfusion index（ HPI）,and ADCperf value in MRI diffusion weighted imaging were measured in different stages of liver fibrosis. The relationship between the parameters and the stage of liver fibrosis were analyzed. Results With the increase of the degree of liver fibrosis,HPI increased gradually,while PVP decreased with the degree of liver fibrosis. PVP negatively correlated with the severity of liver fibrosis,HPI positively correlated with the severity of liver fibrosis（ r =- 0. 589,0. 652 respectively）. The ROC curve showed that PVP or HPI was the best for predicting liver fibrosis on S2 stage and above S2 stage. With the increase of the degree of liver fibrosis,ADCperf values were decreased,and the difference was statistically significant（ P〈0 01）. When ADCperf was used to predict the liver fibrosis on S2 and and above S2 stage,the area under the ROC curve was the largest. ADCperf value were negatively correlated with the severity of liver fibrosis（ r =- 0.720）. Conclusion HPI,PVP and ADCperf can reflect the perfusion changes of liver fibrosis.