单指数、双指数和拉伸指数模型扩散加权成像在眼眶良、恶性肿瘤鉴别诊断中的价值

The value of diffusion-weighted imaging of single index,double index and stretch index models in the differential diagnosis of orbital benign and malignant tumors

目的探讨单指数、双指数及拉伸指数模型DWI在眼眶良恶性肿瘤鉴别中的价值。材料与方法纳入2019年1月至2019年12月经手术病理证实的眼眶肿瘤患者51例,在术前行3.0 T常规磁共振及多b值DWI检查,其中良性26例,恶性25例。利用GE ADW 4.6 Functiontool后处理软件测量单指数模型表观扩散系数(apparent diffusion coefficient,ADC)图,双指数模型的慢速表观扩散系数(slow apparent diffusion coefficient,ADCslow)值、快速表观扩散系数(fast apparent diffusion coefficient,ADCfast)值、灌注分数(perfusion fraction,f)值,以及拉伸指数模型的分布扩散系数(distributed diffusion coefficient,DDC)、扩散异质性指数(the heterogeneity of intravoxel diffusion,α)值,比较各参数值的差异。采用受试者工作特征曲线(receiver operating characteristic curve,ROC)评估有统计学差异的参数对眼眶良、恶性鉴别诊断的效能。结果ADC、ADCslow、DDC及α值在良性肿瘤与恶性肿瘤鉴别诊断中均有显著统计学差异(P<0.05),其中DDC和ADCslow的受试者工作特征曲线下面积最大,分别为0.84和0.81,诊断阈值分别为1.15×10^(-3)mm^(2)/s(敏感度,79.20%;特异度,92.60%)和0.60×10^(-3)mm^(2)/s(敏感度87.50%;特异度66.70%)。结论双指数及拉伸指数模型扩散加权成像为眼眶肿瘤良、恶性的鉴别诊断提供更多信息,ADCslow、DDC与传统单指数DWI生成的ADC值相比,在眼眶肿瘤良、恶性鉴别诊断中具有更大价值,ADCslow、DDC、α三参数联合诊断效能最高。

Objective:To explore the value of single index,double index and stretch index model DWI in the differentiation of orbital benign and malignant tumors.Materials and Methods:Fifty-one patients with orbital tumors confirmed by surgery and pathology from January 2019 to December 2019 were enrolled.They underwent 3.0 T conventional magnetic resonance and multi-b value DWI examination before surgery.Among them,26 were benign and 25 were malignant.Use GE ADW4.6 Functiontool post-processing software to measure the apparent diffusion coefficient(ADC)value of the single exponential model,the slow apparent diffusion coefficient(ADCslow)value,the fast apparent diffusion coefficient(ADCfast),perfusion fraction(f)value of the double exponential model,and the distributed diffusion coefficient(DDC)value、the heterogeneity of intravoxel diffusion(α)value of stretch index model,compare the difference of each parameter value.Receiver operating characteristic curve(ROC)was used to evaluate the effectiveness of statistically different parameters in the differential diagnosis of orbital benign and malignant.Results:ADC,ADCslow,DDC andαvalues were significantly different in the differential diagnosis of benign tumors and malignant tumors(P<0.05).Among them,the area under the receiver operating characteristic curve of DDC and ADCslowwas the largest,respectively 0.84 and 0.81,the diagnostic threshold was 1.15×10^(-3)mm^(2)/s(sensitivity,79.20%;specificity,92.60%)and 0.60×10^(-3)mm^(2)/s(sensitivity 87.50%;specificity 66.70%).Conclusions:Diffusion weighted imaging with double index and stretch index models provides more information for the differential diagnosis of orbital tumors from benign and malignant.Compared with the ADC value generated by traditional single index DWI,ADCslowand DDC have greater advantages in the differential diagnosis of benign and malignant orbital tumors.The combination of ADCslow,DDC,andαhas the highest diagnostic efficiency.