肝硬化结节与小肝癌的MRI研究

The MRI study of nodules with cirrhosis and small hepatocellular carcinoma

目的:回顾性分析肝硬化合并小肝癌、再生结节(RN)及肝不典型增生结节(DN)的MR表现,探讨其MR诊断与鉴别诊断。方法:收集50例结节性肝硬化病例MR检查资料,患者行正反相位T1WI、脂肪抑制T2WI、动态增强扫描和弥散加权(DWI)扫描,总结肝内结节的信号特点。结果:RN在T1WI脂肪抑制上多为等信号或稍高信号,T2WI多为低信号,增强后与周围正常肝组织强化相似或信号稍低;DN在T1WI多为较高信号,T2WI多为稍低或等信号,增强后强化不明显;癌结节T1WI多为稍低或等信号,偶有稍高信号,T2WI多为较高信号,DWI为高信号,强化多为动脉中晚期强化,门静脉期以后强化减退。结论:磁共振平扫加动态增强能对大多数RN、DN和小肝癌结节做出明确诊断和鉴别。

Objective：To retrospectively analyze MR features of regenerative nodules and dysplastie nodules and small hepatocellular carcinoma and to investigate their diagnosis and differential dignosis of MR. Methods： 50 cases MRI with cir- rhosis were collected. All the examinations were performed with fat saturate T2 WI, in/out-phase T1 WI, and dynamic gad- olinium-enhanced scan, and diffusion weighted imaging to summarize their MR features of signals. Results：The most re- generating nodules （RN） are isointense or slightly hyperintense on fat saturate T~ WI and hypointense on T2WI. After dy- namic gadolinium-enhanced scan, there is isointense or slightly hypointense. The most dysplastic nodules （DN） are hyper- intense on T1 WI and slightly hypointense or isointense on T2 WI, and even more they almost have no obvious enhance- ment. The most small hepatocellular carcinoma are isointense or slightly hypointense on T1 W1, small fraction cases are slightly hyperintense on T1WI, most cases are hyperintense on T2 WI and DWI. After dynamic gadolinium-enhanced scan, there is enhancement on the middle-late period of arterial phase and slight enhancement on portal venous phase. Conclu- sion： Most of the RN, DN and sHCC can be distinguishedly diagnosed by comprehensive analysis of the different sequence and dynamic Gd-DTPA enhanced imaging.