表观扩散系数值对肝脏占位性病变的定量诊断价值

Value of Apparent Diffusion Coefficient in Quantitative Diagnosis of Benign and Malignant Liver Lesions

目的探讨磁共振扩散加权成像(DWI)中表观扩散系数(ADC)值对肝脏占位性病变的鉴别诊断价值。方法经先期研究确定相对合理的两个b值组合(0、300)s/mm2和(0、800)s/mm2,对经病理或临床随访及相关辅助检查证实的112例共145个肝脏占位性病灶行常规MR平扫、增强及b值=(0、300、800)s/mm2DWI扫描,分别比较各种病变的ADC值。结果恶性、良性组的平均ADC值,b=300 s/mm2时分别为(1.15±0.20)×10-3mm2/s、(2.13±0.53)×10-3 mm2/s;b=800 s/mm2时分别为(0.98±0.19)×10-3 mm2/s、(1.81±0.42)×10-3 mm2/s;两者间ADC值比较,差异均有统计学意义(P<0.05)。b=300 s/mm2,以ADC值≤1.40×10-3mm2/s为鉴别良恶性病变的阈值,诊断的敏感性、特异性分别为92.0%和80.0%;b=800 s/mm2时,以ADC值≤1.14×10-3mm2/s为阈值,诊断的敏感性、特异性分别为92.0%和85.0%。结论 ADC值对肝脏良恶性病变的鉴别诊断有较高价值。

Objective To evaluate the diagnotic value of magnetic resonance apparent diffusion coefficient （ADC） of diffusion-weighted imaging（DWI） in the discrimination of benign and malignant liver lesions. Methods One hundred and twelve patients with 145 lesions confirmed by pathology and clinical diagnosis underwent DWI （diffusion factors of 300 s/mm2 ,800 s/mm2） examinations by 1.5T MR.A comparison analysis was done in ADC values of the lesions. Results Tne average ADC values of benign and malignant group were（1.15±0.20）×10^-3mm^2/s、（2.13±0.53）×10-3mm^3/s;b=800s/mm^2,respectively ;And they were（0.98±0.19）×10^-3mm^2/s、（1.81±0.42）×10^-3mm^2/s, respectively. ADC value showed significant difference between two groups（P 〈0.05）. The sensitivity and accuracy of differentiating the malignant from the benign with a cut-off point of 1.40×10^-3 mm^2/s were 92.0%, 80.0% （b = 300 mm2/s） ,respectively. The sensitivity and accuracy of differentiating the malignant from the benign with a cut-off point of 1.14×10^-3mm^2/s were 92.0%, 85.0% （ b = 800 mm2/s）, respectively. Condusion ADC value has moderate diagnosis potency in differential diagnosis of benign and malignant liver lesions.