【摘要】 目的 评价在磁共振（MR）扩散加权成像（DWI）中,2种感兴趣（ROI）选取方法对乳腺病变表观扩散系数（ADC）测量值的影响。方法 选择因乳腺包块进行术前乳腺MR平扫、DWI扫描和MR动态增强扫描的53例患者, 2名医师在不知道组织病理检查结果的情况下,分别采用固定ROI（10 mm²±mm²）方法和常规ROI方法测量乳腺病灶的ADC值并进行统计学比较,同时采用受试者工作特征（ROC）曲线分析2种方法测量所得的ADC值对乳腺癌诊断的价值。结果 53例乳腺疾病患者中共有62个病灶,恶性病灶33个,良性病灶29个。医师1用固定ROI方法测得良性病灶ADC平均值为（1.647±0.359）×10^-3 mm²/s,恶性病灶ADC平均值为（1.136±0.227）×10^-3mm²/s,ADC值诊断乳腺癌的ROC曲线下面积为0.897;其采用常规ROI方法测量的值依次为(1.603±0.415×10^-3mm²/s,（1.251±0.237）×10^-3mm²/s和0.768。医师2用固定RDI方法测得ADC平均值为（1.647±0.357）×10^-3mm²/s和（1.130±0.250）×10^-3mm²/s,用常规ROI方法测得的ADC平均值为（1.590±0.390）×10^-3mm²/s和（1.250±0.237）×10^-3 mm²/s。对于良性病灶,2种方法测得的ADC平均值差异无统计学意义（P=0.528）,对于恶性病灶,其差异有统计学意义（P=0.002）,显示固定ROI方法对于乳腺疾病的诊断价值优于常规ROI方法（P=0.008）。2名医师分别用2种方法测量的良、恶性病灶的ADC平均值差异均无统计学意义（P均>0.05）。结论DWI可提高乳腺疾病的良、恶性鉴别诊断效能,固定ROI方法测ADC平均值优于常规ROI方法,更能体现恶性病灶的特征。更多还原

【Abstract】 Objective To evaluate two methods of selecting region of interest（ROI） to measure the apparent diffusion coefficient（ADC） of breast lesions on diffusion-weighted imaging（DWI）.Methods MRI findings（including plain MRI,dynamic contrast-enhanced MRI and DWI） of 53 cases with breast mass confirmed by pathology were analyzed retrospectively.Two observers independently measured the ADC of breast lesions by the method of fixed ROI with the size of 10 mm²±2 mm² and the routine method.The mean ADCs of benign and malignant breast lesions were compared between two methods and two observers by using paired samples T-test.The values of ADC diagnosing breast cancer were compared between the two methods by using the receiver operating characteristic（ROC） curve.Results Among 62 lesions of 53 cases,33 lesions were malignant,and 29 lesions were benign.For the first observer,the mean ADCs of benign and malignant lesions were（1.647±0.359） × 10 mm²/s and（1.136±0.227） × 10^-3mm²/s measured by the fixed ROI method,respectively.The area under the ROC was 0.897.The mean ADCs of benign and malignant lesions were（1.603×0.415） × 10^-3mm²/s and（1.251 ×0.237） ×10^-3 mm²/s measured by the routine method,respectively.The area under the ROC was 0.768.For another observer,the mean ADCs of benign and malignant lesions were（1.647±0.357） ×10^-3mm²/s and（1.130±0.250） × 10^-3mm²/s measured by the fixed ROI method,respectively.The mean ADCs of benign and malignant lesions were（1.590× 0.390） × 10 ^-3 mm²/s and（1.250±0.237） × 10^-3mm²/s measured by the routine method,respectively.There was no significant difference for the mean ADC of benign lesions between the two methods.However,there was significant difference for the mean ADC of malignant lesions between the two methods.The diagnostic value of ADC measured by the fixing method was better than that of the routine method（P=0.008）.There were no significant differences for ADCs of benign and malignant lesions between the two observers.Conclusion DWI has an important value for differential diagnosis of benign and malignant breast lesions.The measurement of ADC by the fixed and smaller ROI is better than that by the routine ROI for distinguishing malignant from benign breast lesions.更多还原