不同b值MR扩散加权成像对乳腺良恶性肿瘤鉴别诊断价值研究

The study of multi-b value MR diffusion weighted imaging in differentiation of breast benign and malignant tumors

目的探讨不同b值MR扩散加权成像(diffusion weighted imaging,DWI)及ADC(apparent diffusion coeffi cient)值对乳腺良恶性肿瘤的鉴别诊断价值。材料与方法搜集乳腺肿瘤患者共36例,其中恶性24例,良性12例,均经穿刺或手术病理证实。乳腺DWI成像采用4个b值(分别为0、400、800和1000 s/mm2),分别计算乳腺良恶性肿瘤不同b值条件下共3组ADC值。结果乳腺恶性肿瘤ADC值均低于良性者,乳腺良恶性肿瘤不同b值条件下ADC值均有统计学差异。当b=800 s/mm2时,取ADC值为1.33×10-3 mm2/s为良恶性肿瘤的界定值,诊断的敏感性和特异性分别为84.7%和79.8%。当b=1000 s/mm2时,以ADC值为1.15×10-3 mm2/s为良恶性肿瘤的界定值,诊断的敏感性和特异性分别为92.2%和90.6%。结论 DWI对乳腺良恶性肿瘤的诊断具有重要价值,b值为1000s/mm2时具有较高的诊断准确性。

Objective：To explore the value of multi-b value MR Diffusion Weighted Imaging （DWI） and ADC （apparent diffusion coefifcient） in differentiation of breast benign and malignant tumors. Materials and Methods： Thirty-six cases of breast tumors including 24 malignant and 12 benign tumors were collected, all of which were conifrmed by biopsy or surgery pathology. All of 4 b values （0, 400, 800, 1000 s/mm2） were performed on DWI examination, and 3 groups of ADC value were generated. Results：The ADC value of malignant tumors was lower than that of benign tumors. There exists statistic signiifcance of ADC value between benign and malignant breast tumors in different b value. The sensitivity and specificity of ADC was 84.7% and 79.8% when b=800 s/mm2 and set 1.33×10^-3 mm2/s as the upper bound. And the sensitivity and specificity of ADC was 92.2% and 90.6% when b=1000 s/mm2 and set 1.15×10^-3 mm2/s as the upper bound. Conclusions： DWI has great value in the differentiation of breast benign and malignant tumors, and it has most diagnostic accuracy when b was set 1000 s/mm2.