磁共振体素内不相干运动定量评估乳腺良恶性病变的价值

The value of parameters derived from diffusion-weighted imaging intravoxel incoherent motion model in the diagnosis of benign and malignant breast lesions

目的:讨论磁共振体素中不相干运动(IVIM)扩散加权成像(DWI)的定量参数值在乳腺良恶性病变评价中的意义。方法:收集温州医科大学附属第二医院2017年1月至12月期间行乳腺MR检查并经病理证实乳腺病变的50例患者,所有患者进行多b值DWI(b=0~2000 s/mm^2)检查,测定相应乳腺病变IVIM的定量参数,包括标准化表观扩散系数(ADC standard)、真实扩散系数(D)、假性扩散系数(D*)和灌注分数(f)。根据病理结果,将患者分为2组,其中21例为恶性(恶性组),29例为良性(良性组);对2组病变的IVIM参数进行统计学分析,比较2组间的差异,绘制ROC曲线并分析其诊断效率。结果:良性组和恶性组的ADC standard和D值差异有统计学意义(P<0.05),D*值与f值差异无统计学意义(P>0.05)。在恶性组中,ADC standard、D值分别是(1.10±0.38)×10^-3 mm^2/s、(0.88±0.24)×10^-3 mm^2/s,明显低于良性组的(1.69±0.26)×10^-3 mm^2/s、(1.56±0.25)×10^-3 mm^2/s,ADC standard和D值诊断良恶性病变的ROC曲线下面积为0.879、0.966,诊断的最佳阈值为1.26×10^-3 mm^2/s、1.18×10^-3 mm^2/s,ADC standard对乳房的良恶性肿瘤敏感度和特异度分别为83.33%、95.45%,D值的敏感度和特异度分别为91.67%和90.91%。结论:IVlM模型获得的定量参数有助于对乳腺良恶性病变进行鉴别诊断,其中D值是判别良恶性乳腺病变的最佳诊断指标。

Objective:To evaluate the quantitative parameter values of incoherent motion diffusion weighted imaging(IVIM)in magnetic resonance magnetins for the diagnosis of mammary good malignant lesions.Methods:Totally 50 cases who underwent breast MR and confirmed pathologically were collected from January to December,2017 in the Second Affiliated Hospital of Wenzhou Medical University.Multiple b-value DWI(b=0-2000 s/mm^2)was examined for all patients,and quantitative parameters of IVIM disease levels were measured,including standardized epigenetic diffusion coefficient(ADC standard),true diffusion coefficient(D),false diffusion coefficient(D*)and perfusion score(f).According to their pathological results,the patients were divided into 2 groups,with 21 malignant(malignant group)and 29 benign(benign group).Their IVIM parameters of lesions were statistically analyzed,the differences between the two groups were compared,the ROC curve drawn,and the diagnostic efficiency was analyzed.Results:There was significant difference between the benign group and the malignant group in ADC standard and D value(P<0.05),while there was no statistical difference between the D*-value and the f-value(P>0.05).In the malignant group,the ADC standard and D values were(1.10±0.38)×10^-3 mm^2/s,(0.88±0.24)×10^-3 mm^2/s,significantly lower than the ADC standard and D values in the benign group(1.69±0.26)×10^-3 mm^2/s,(1.56±0.25)×10^-3 mm^2/s,ADC standard and D value diagnosed as good malignant lesions ROC area 0.879,0.966,best threshold for diagnosis is 1.26×10^-3 mm^2/s,1.18×10^-3 mm^2/s.ADC standard’s sensitivity and specificity to good malignant tumors in the breast were 83.33%and 95.45%respectively,and the sensitivity and specificity of D value were 91.67%and 90.91%respectively.Conclusion:The quantitative parameters obtained by the IVlM model are helpful to the differential diagnosis of mammary malignant lesions,of which the D value is the best diagnostic index to distinguish between good malignant mammopathy.