乳腺MRI常规成像、动态增强成像、扩散加权成像对良恶性病变的诊断评价

目的:探讨磁共振常规成像(MRI),动态增强成像(DCE-MRI),扩散加权成像(DWI)及其联合成像对乳腺疾病的诊断价值。方法:47例经过手术及病理证实的乳腺病变,恶性31个,良性16个。所有病灶均行常规MRI、DCE-MRI及DWI。以术后标本病理结果作为金标准,评价4种检查方法对乳腺疾病定性的诊断价值。结果:常规MRI及DCE-MRI诊断乳腺病变的敏感性分别为74.2%、87.1%,特异性为50%、62.5%,准确率为70%、78.7%。ROC曲线分析确定ADC良恶性诊断阈值为1.20×10-3mm2/s,ADC值诊断及联合诊断敏感性分别为93.55%、87.1%,特异性为75%、81.3%,准确性为87.23%、85.1%。结论:①常规MRI及DCE-MRI诊断良恶性病变特异性较低,结合DWI综合诊断能提高特异性。②DWI诊断良恶性病变的敏感性高,可作为乳腺癌的筛查序列。恶性病变ADC值多≤1.20×10-3mm2/s。

Diagnostic Value of MRI Scanning,Dynamic Contrast-Enhanced MRI and Diffusion-Weighted MRI in Breast Diseases

Objective:To approach the value of MRI scanning,dynamic contrast-enhanced MRI(DCE-MRI)and diffusion-weighted MR imaging(DWI)in the diagnosis of breast diseases.Methods:Forty-seven breast lesions from forty-five patients,including thirty-one malignant lesions and sixteen benign lesions,were examined.The validities of dynamic contrast-enhanced imaging,ADC, and combination of the two methods were evaluated according to the histopathology result.Results:The sensitivity,specificity,and accuracy of MRI scanning and dynamic contrast-enhanced imaging respectively were 74.2%,87.1%,50% and 62.5%,66%,78.7%respectively.The threshold of ADC for diagnosis was 1.2×10-3 mm2/s by ROC analysis.The sensitivity,specificity,and accuracy of ADC were 93.6%,75%,and 87.2% respectively.The sensitivity,specificity and accuracy of combination of dynamic contrast-enhanced MRI and DWI-ADC were 83.9%,87.5% and 85.1% respectively.Conclusion:① The specificity of MRI scanning and dynamic contrast-enhanced MRI imaging is low,but the combination of dynamic contrast-enhanced MRI and DWI can increase the specificity.② The sensitivity of DWI is high,and it is helpful to screen the malignant breast lesions from the benign.Most ADC values of malignant brest lesions are no more than 1.2×10-3 mm2/s.