扩散加权成像鉴别常见实性肝脏局灶性病变的应用研究

Study on value of diffusion weighted imaging in differentiation of solid focal liver lesions

目的评价扩散加权成像(DWI)序列及表观扩散系数(ADC)在鉴别实性肝脏局灶性病变(SFLL)的应用价值。方法采用GE公司Signa 1.5T磁共振扫描机(MR)对142例共158个SFLL进行屏气磁共振加权成像(DWI),b=500s/mm2,所有病灶包括未成熟肝脓肿7例,局灶性结节增生(FNH)12例,肝细胞肝癌(HCC)74例,胆管细胞癌26例,肝转移癌39例。分析各类病灶的DWI信号强度、ADC值及其差异。结果 24个病灶表现为高信号,132个病灶表现为稍高信号,2个病灶表现为等信号。未成熟肝脓肿、FNH、肝细胞性肝癌、胆管细胞癌、肝转移癌的ADC值(×10-3 mm2/s)分别为(1.48±0.23)、(1.75±0.26)、(1.23±0.43)、(1.47±0.35)、(1.36±0.33)。FNH与其他SFLL的ADC值比较,差异有统计学意义(P<0.01),未成熟肝脓肿与肝细胞性肝癌、胆管癌、转移癌的ADC值比较,差异均无统计学意义(P>0.05)。结论 DWI信号强度及ADC值在一定程度上有助于实性肝脏局灶性病变的鉴别诊断。

Objective To evaluate diffusion weighted imaging （DWI） sequence and apparent diffusion coefficient （ADC） in differentiation of various solid focal liver lesions（SFLL）commonly encountered. Methods 142 cases with 158 SFLLs underwent breath-hold diffusion weighted imaging（DWI）（b= 500 s/mmz） using a 1.5 Tesla MR scanner. The cases included 7 cases of imma- tured abscesses,12 cases of FNHs,74 cases of hepatic cell cancer,26 cases of cholangiocarcinomaes and 39 cases of metastasises. The signal intensity on DWI,ADC value and the difference for each type of SFLLs were measured and analyzed. Results 24 cases of SFLLs were manifested as high signal intensity, 132 cases of SFLLs manifested as slightly high signal intensity and only 2 cases of SFLLs manifested as iso-signal intensity on DWI sequence. The mean ADC value（ × 10^-2 mm^2/s）for immatured abscesses, FNHs, HCCs, cholangiocarcinomaes, metastasises were （ 1.48 ± 0. 23 ）, （ 1. 75 ± 0. 26 ）, （ 1. 23 ± 0. 43 ）, （ 1. 47 ±0. 35 ）, （ 1. 36 ± 0.33） ,respectively. The difference in ADC values between FNH patients and other SFLLs patients showed statistically significant （P〈0.01） ,while HCCs immatured abscesses and malignant SFLLs showed no statistical significance（P〉0.05）. Conclusion The signal intensity on DWI and ADC values may be helpful for diagnosing solid focal liver lesions.