MRI对肝脏上皮样血管平滑肌脂肪瘤与肝细胞肝癌鉴别诊断的价值

目的 比较动态增强磁共振成像(DCE-MRI)和扩散加权成像(DWI)对肝脏上皮样血管平滑肌脂肪瘤(HEAML)和肝细胞肝癌(HCC)鉴别诊断的价值.方法 回顾性分析经手术病理证实的15例HEAML患者和50例HCC患者MR资料,术前均行DCE-MRI和 DWl扫描.观察记录2组病灶的大小、部位、边界、平扫信号特点(包括T1WI、T2WI及DWI),增强模式、中心血管影、有无早期静脉引流、"假包膜",计算表观扩散系数(ADC)值,并对2组病例上述MR征象进行统计学比较分析.结果 所有病例均为单发病灶.15个HEAML病灶8个显示早期静脉引流、11个显示中心血管征、6个有假包膜、5个为"快进快出"强化模式、10个为"快进慢出"强化模式,ADC平均值为(1.15±0.31)×10-3 mm2/s;50个HCC病灶中,6个显示早期静脉引流、5个显示中心血管征、45个有"假包膜"、29个为"快进快出"强化模式,ADC平均值为(1.23±0.29)×10-3 mm2/s.两者在病灶中心血管影、早期静脉引流、"假包膜"征方面差异有统计学意义(P<0.05),在病灶部位、大小、边界、平扫信号特点(包括T1WI,T2WI及DWI)、强化模式、ADC值方面差异无统计学意义(P>0.05).结论 DCE-MRI较DWI更有助于鉴别HEAML和HCC.

The value of MRI in differentiating hepatic epithelioid angiomyolipoma from hepatocellular carcinoma

Objective To compare the value of dynamic contrast-enhanced MRI(DCE-MRI) and diffusion weight-imaging(DWI) in differentiating hepatic epithelioid angiomyolipoma (HEAML) from hepatocellular carcinoma(HCC).Methods The MR data of 15 HEAML and 50 HCC proved surgically and pathologically were analyzed retrospectively.The DCE-MRI and DWI were performed preoperatively.The size, location, margin, T1-weighted images(T1WI),T2-weighted images(T2WI) and DWI signal intensity(SI),enhancement pattern, central vessel, early draining vein, pseudocapsule were recorded.The apparent diffusion coefficient (ADC) value was also calculated.The differences of these MR features between two groups were compared statistically.Results There was one lesion in each patient.For all 15 HEAML lesions, early draining vein, central vessel and pseudocapsule were displayed in 8,11 and 6 lesions, respectively.The "wash in and slow out" enhancement pattern was shown in 10 lesions and "wash in and wash out" pattern shown in others (5/15).The mean ADC value was (1.15±0.31)×10-3 mm2/s.For all 50 HCC lesions, early draining vein, central vessel and pseudocapsule were displayed in 6,5 and 45 lesions, respectively.29 lesions were shown as "wash in and wash out" enhancement pattern and the others (21/50) as "wash in and slow out" pattern.The mean ADC value was (1.23±0.29)×10-3 mm2/s.There were significant differences in these MR features including draining vein, central vessel and pseudocapsule (P<0.05), but no differences in size, location, margin, SI(T1WI, T2WI and DWI), dynamic enhancement pattern, ADC value(P>0.05) between HEAML and HCC.Conclusion DCE-MRI is more helpful in differentiating HEAML from HCC than DWI.