扩散加权成像鉴别乳腺良恶性病变的价值

目的 探讨MR扩散加权成像(DWI)的技术及表观扩散系数(ADC)值对乳腺良、恶性病变的诊断价值.方法 经病理证实的乳腺病变53例:恶性病灶35个,良性病灶22个.扩散敏感系数(b值)取0、500、1000 s/mm2,以恶性病变的ADC值95%可信区间的上界作为诊断病变良、恶性的界值,所得结果与病理结果比较.结果 DWI显示95.5%(21/22)的良性病变,97.1%(34/35)的恶性病变,敏感性96.5%(55/57).恶性病变组的ADC值与良性病变组或正常腺体组的ADC值差异均有统计学意义.我们把良、恶性病变ADC值的界值定为0.98×10-3 mm2/s,即＜0.98为恶性,＞0.98为良性.乳腺ADC值随着b值的增大而减少.结论 依据ADC值可以对乳腺良、恶性病变作出诊断和鉴别诊断;ADC值随着乳腺病变的不同和采用的b值的不同而改变,b值取1000 s/mm2时对乳腺良、恶性病变的诊断最有价值.

Diagnostic value of MR diffusion weighted imaging in differentiation of benign from malignant breast lesion

Objective To study the diagnostic value of magnetic resonance(MR) diffusion weighted imaging(DWI) in differentiation of benign from malignant breast lesion.MethodsA total of 35 malignant lesions and 22 benign lesions in 53 cases were diagnosed pathologically.0,500 and 1000 s/mm2 were taken as the diffusion sensitive coefficients(b value) and the upper bound of 95% confidence interval of apparent diffusion coefficient (ADC) value was taken as the standard for differentiating the benign from malignant lesion.The results of EWI were compared with those of pathology.Results DWI showed the benign in 95.5%(21/22) of benign lesions and the malignant in 97.1% (34/35) of malignant lesions with a sensitivity of 96.5%(55/57).The ADC value of malignant lesions was statistically different from that of normal or benign breast tissues,which was not significantly different between normal and benign breast tissues.When 0.98×10-3 mm2/s was taken as the the upper bound,the b value increased as the ADC level declined.Conclusion ADC value is an important parameter for differenciating the benign from the malignant breast lesions.ADC level is correlated with the types of breast classification and is influenced by the b value.A b value of 1000 s/mm2 is of most significance for differenciating the benign from the malignant breast lesions.