目的探讨MRI扩散加权成像 (MRI-DWI)与三维超声对乳腺肿块良恶性 鉴别诊断的临床价值。方法 本医院2015 年5月-2018年2月期间收治的50例乳腺肿 块患者入院后均行乳腺MRI-DWI、三维超 声检查，前者分析乳腺肿块的形态学表 现、血流动力学等，并测量正常乳腺组织 及可见病变的表观弥散系数(ADC）值；后 者分析三维超声造影图像评分。均经手术 切除或穿刺活检获取病理学诊断结果。 结果 50例患者中病理为良性肿块31例 (62.00%），恶性肿块者19例(38.00%）。 方差分析显示，平均ADC值正常腺体＞良 性肿块＞恶性肿块，差异有统计学意义(P ＜0.05）。以ADC＜1.26×10-3mm2 /s时诊 断为恶性乳腺肿块，准确率、敏感度、特 异度分别为84.00%、84.21%、83.87%，受 试者工作特征(ROC）曲线下面积为0.86。 秩和检验分析显示，良性、恶性乳腺肿块 三维超声造影评分比较有统计学意义(P ＜0.05）；三维超声造影诊断良恶性乳腺 肿块的准确率、敏感度、特异度分别为 76.00%、68.42%、80.65%，均低于MRIDWI诊断。结论 与三维超声造影相比， MRI-DWI对良、恶性乳腺肿块的鉴别诊断 效能更高。

Objective To investigate the clinical value of MRI diffusion-weighted imaging (MRI-DWI) and three-dimensional ultrasound in the differential diagnosis of benign and malignant breast masses. Methods 50 cases of patients with breast masses admitted to the hospital between May 2015 and February 2018 were examined by MRI-DWI and threedimensional ultrasound after admission. The former was used to analyze the morphological features and hemodynamics, etc. of breast masses and measure the apparent diffusion coefficient (ADC) values of normal breast tissues and visible lesions. The latter was used to analyze the three-dimensional ultrasound image score. Surgical excision or biopsy were performed to obtain results of pathological diagnosis. Results In the 50 patients, there were 31 cases (62.00%) of pathologically diagnosed benign masses and 19 cases (38.00%) of malignant masses. Analysis of variance showed that the mean ADC value of normal gland > benign masses > malignant masses (P<0.05). With ADC<1.26×10-3mm2 /s as the standard for malignant breast masses, the accuracy, sensitivity and specificity were 84.00%, 84.21% and 83.87%, respectively, and the area under the receiver operating characteristic (ROC) curve was 0.86. The rank sum test showed that there were statistically significant differences in three-dimensional contrast-enhanced ultrasound scores between benign and malignant breast masses (P<0.05). The accuracy, sensitivity and specificity of threedimensional contrast-enhanced ultrasound in the diagnosis of benign and malignant breast masses (76.00%, 68.42% and 80.65%) were lower than those of MRI-DWI. Conclusion Compared with three-dimensional contrast-enhanced ultrasound, MRI-DWI is more effective in the differential diagnosis of benign and malignant breast masses.