MRI肝内不典型影像表现病灶的动态增强与肿瘤良恶性的相关性研究

Correlative Study of dynamic enhancement of MRI atypical imaging lesions in liver with benign and malignant tumors

目的探讨MRI肝内不典型表现病灶的良恶性鉴别特征。方法回顾性分析最常见良恶性肿瘤(肝细胞癌、肝内胆管细胞癌、肝血管瘤、肝细胞腺瘤)的时间信号强度曲线(TIC)类型、表观扩散系数(ADC)值及其灌注参数,发现不典型病灶良恶性肿瘤的特征性表现。结果肝癌和肝内胆管细胞癌典型表现病灶的TIC曲线表现均为速升速降型,而不典型表现病灶表现均为平台型,两者的TIC曲线转折点之后直线的斜率(Kup)<0。肝血管瘤典型表现病灶的TIC曲线表现为持续上升型,而不典型表现病灶表现为平台型;肝细胞腺瘤典型表现病灶的TIC曲线表现为慢上慢下型,而不典型表现病灶表现为平台型;肝血管瘤和肝细胞腺瘤的Kup>0。肝细胞癌、肝内胆管细胞癌、肝血管瘤、肝细胞腺瘤典型病灶与不典型病灶的ADC值比较,差异均无统计学意义(t分别=1.51、0.93、1.36、0.39,P均>0.05)。肝内恶性肿瘤(肝细胞癌、肝内胆管细胞癌)典型与不典型病灶的Tin比较,差异不具有统计学意义(t分别=0.95、0.45,P均>0.05),而其Tout和Kup比较,差异均具有统计学意义(t分别=11.40、7.80、6.08、5.42,P均<0.05)。肝内良性肿瘤(肝血管瘤、肝细胞腺瘤)典型与不典型病灶的Tin和Tout差异不具有统计学意义(t分别=0.21、1.70、0.38、0.43,P均>0.05),而其Kup具有统计学意义(t分别=8.12、8.51,P均<0.05)。肝内恶性肿瘤组(肝癌和肝内胆管细胞癌)的Ktrans平均值与良性肿瘤组(肝血管瘤和肝细胞腺瘤)比较,差异有统计学意义(t=8.27,P<0.05)。结论传统MRI的根据病灶TIC曲线和ADC值鉴别不典型表现病灶的良恶性具有较大的局限性,结合灌注参数鉴别良恶性性质具有重要的意义,尤其是Kup的正负对良恶性鉴别最具特征。

Objective To explore the feature to distinguish the benign and malignant tumors of atypical imaging lesions in liver. Methods The time intensity curve（TIC）,the value of apparent diffusion coefficient（ADC） and perfusion parameters of lesions in liver were retrospective analyzed to explore characteristics of the benign and malignant tumors of atypical imaging lesions in liver. Results The TIC curve of typical manifestations lesion in liver cancer and intrahepatic bile duct cell carcinoma showed rapidly rise and fall,and atypical lesions showed platform. The Kupof both types were less than 0. The TIC curve of typical manifestations lesion in hepatic hemangioma showed gradually rise,and atypical lesions showed platform. The TIC curve of typical manifestations lesion in hepatocellular adenoma showed slowly rise and fall,and atypical lesions showed platform. The Kupof both types were greater than 0. The differences of ADC value of typical and atypical lesions in liver cancer,intrahepatic bile duct cell carcinoma,hepatic hemangioma and hepatocellular adenoma was not statistically significant（t =1.51,0.93,1.36,0.39,P 〉0.05）.There was no statistically significant difference in Tinof typical and atypical lesions in malignant tumor of liver（t = 0.95,0.45,P 〉0.05）. There was statistically significant difference in Toutand Kup（t =11.40,7.80,6.08,5.42,P〈0.05）.There was no statistically significant difference in Tinand Tout of typical and atypical lesions in intrahepatic benign tumor（t =0.21,1.70,0.38,0.43,P 〉0.05）.There was statistically significant in Kup（t =8.12,8.51,P 〈0.05）.The difference of Ktrans level of malignant and benign tumor of liver was statistically significant（t =8.27,P 〈0.05）.Conclusion There were limitations of identifying the benign and malignant in atypical lesions according to traditional methods of the type of time-intense-curve and the value of ADC. Combining with the perfusion parameters,especially the Kup,play a important role in distinguishing benign and malignant.