中文摘要：

目的 探讨原发性肝细胞癌（HCC）癌前病变血液动力学的特征。方法 用MR灌注扫描（MR perfusion，MRP）的方法对实验诱发大鼠肝脏的HCC癌前病变阶段到癌变阶段的血液动力学进行动态观察。结果 在MRT2WI检出并与病理对应良好的46个结节中有9个再生结节（regenerative nodule，RN）、22个HCC癌前病变即发育不良结节（dysplastic nodule，DN）、10个早期HCC和5个HCC。RN、DN、早期HCC和HCC结节及邻近肝实质的平均阳性强化积分值（positive enhancenlent integral，PEI）分别为20567±3117、16194±2074、22609±3483、49186±4461、20484±7019。将结节PEI值和结节旁肝组织PEI值对比，发现9个RN与邻近肝实质差异无统计学意义（t=-5.30，P=006），MRP图像的动脉期和门脉期RN均呈等信号；DN较邻近肝实质低，并有统计学意义（t=-3.4，P=002），DN的血流灌注曲线于动脉后期较邻近肝实质下降，MRP图像动脉期呈等信号，门脉期为低信号。10个早期HCC中4个结节表现为低灌注，PEI值低于邻近肝实质，动脉期呈稍低信号，门脉期为等信号；6个早期HCC显示为稍高灌注，PEI值稍高于邻近肝实质，动脉期为稍高信号，门脉期呈稍低信号。5个HCC呈典型的动脉期明显强化、门脉期呈相对低信号，结节灌注曲线动脉段较邻近肝实质有明显抬高，结节较邻近肝实质的PEI明显增大，差异有统计学意义（t=3.74，P=002）。结论 MRP能反映HCC癌前病变结节演变过程中血流的改变，HCC的血流灌注量较邻近肝实质明显增多；DN的血流灌注量较邻近肝实质减少。

英文摘要：

Objective To deterlnine the helnodynalnic changes in precancerous lesions of HCC using MR peffusion（MRP）. Methods During the period of carcinogenesis （ 12 - 20 weeks）, 18 Wistar rats induced by DEN to develop into liver nodule lesions froln hepatic cirrhosis were scanned by MR peffusion ever7 week and colnpared lesion to lesion , lesion to liver with pathology. Results Alnong 46 nodules showed by T2WI of MRI and corresponded well with MR ilnages and pathology, we identified 9 regenerative nodules （ RN）, 22 dysplastic nodules（ DN）, 10 early stage HCC （eHCC） and 5 HCC. The average positive enhancelnent integral （ PEI ） values of RN. DN. early HCC. HCC and hepatic parenehylna nearby of the nodtdes were 205.67 ± 31.17,161.94± 20.74,226.09 ± 34. 83,491.86± 44. 61,204.84 ± 70.19 respectively. Colnparing the blood perfusion between nodule and surrounding hepatic parenchylna, we found no difference with RNs. There were significant differences with dysplastic nodules （t = - 3.64, P = 0. 02） which lnanifested decreased blood peffusion. Four of 10 early stage of HCCs demonstrated less blood peffusion and 6 displayed lninor increased blood flow. Five HCC showed typical increased blood supply with significant difference （ t = 3.74, P = 0. 02 ）. Conclusion Non-invasive MR perfusion ilnaging could delnonstrate the changes of blood supply in precancerous lesions of hepatocellular carcinolna. Blood peffusion of HCC increased and DN decreased when compared with surrounding hepatic parenchyma.