DWI联合最小ADC值对鉴别诊断颅内孤立性纤维性肿瘤/血管外皮细胞瘤与脑膜瘤的价值

The value of DWI combined with minimum ADC value in differential diagnosis of intracranial solitary fibrous tumor/hemangiopericytoma and meningioma

目的用扩散加权成像(diffusion weighted imaging,DWI)联合最小表观扩散系数(minimum apparent diffusion coefficient,MinADC)值鉴别诊断颅内孤立性纤维性肿瘤/血管外皮细胞瘤(solitary fibrous tumor/hemangiopericytoma,SFT/HPC)与脑膜瘤,以提高术前诊断准确率。材料与方法回顾性分析2012年3月至2018年8月我院经手术病理证实的颅内10例SFT/HPC (WHOⅡ级)患者与22例脑膜瘤(WHOⅡ级)患者的术前临床资料、DWI特征及病理资料,在ADC图上测量两者的MinADC值并进行比较。通过Welch检验进行两组MinADC值的比较,运用受试者工作特征曲线(receiver operating characteristiccurve,ROC曲线),评价MinADC值的鉴别诊断价值。结果在10例SFT/HPC中,肿瘤实性成分在DWI上8例呈等信号,2例呈稍高信号,MinADC平均值为(1.16±0.23)×10-3 mm2/s;在22例脑膜瘤中,肿瘤实性成分在DWI上18例呈稍高信号,2例呈等信号,2例明显高信号,MinADC值平均值为(0.80±0.12)×10-3mm2/s,小于SFT/HPC,两组肿瘤实性成分MinADC值比较差异有统计学意义(P<0.01)。以MinADC值0.90×10-3 mm2/s为阈值诊断SFT/HPC与脑膜瘤,ROC曲线下面积为0.92±0.32,敏感度为97.6%,特异度为94.3%,与病理组织学结果行一致性检验,SFT/HPC的重复测量的Kappa值为0.91,脑膜瘤的Kappa值为0.87。结论 MinADC值可以作为一种量化工具区分颅内SFT/HPC与脑膜瘤,提高术前诊断准确率。

Objective:Differential diagnosis of intracranial solitary fibrous tumor/hemangiopericytoma(SFT/HPC)and meningioma by diffusion weighted imaging(DWI)combined with minimum apparent diffusion coefficient(MinADC)to improve preoperative diagnostic accuracy.Materials and Methods:Retrospective analysis of preoperative clinical data,DWI characteristics and pathological data of 10 patients with SFT/HPC(WHOⅡgrade)and 22 patients with meningioma(WHOⅡgrade)confirmed by surgery and pathology from March 2012 to August 2018.MinADC value of the SFT/HPCs(n=10)was measured on ADC map and was compared with that of meningiomas(n=22).Comparison of MinADC values between SFT/HPC and meningioma was conducted by Welch test.Using the receiver operating characteristic curve(ROC curve)to evaluate the differential diagnosis value of MinADC value.Results:In 10 cases of SFT/HPC,the solid components of the tumor showed equal signal(n=8)and slightly higher signal(n=2)on DWI,the mean value of MinADC was(1.16±0.23)×10^-3 mm^2/s.In 22 cases of meningioma,the solid components of the tumor showed slightly higher signal(n=18)and equal signal(n=2)and high signal(n=2)on DWI,the mean value of MinADC was(0.80±0.12)×10^-3 mm^2/s,less than that of SFT/HPC,the difference of MinADC values between the two groups was statistically significant(P<0.01).For the differentiation between SFT/HPC and meningioma,the critical cutoff MinADC value was 0.90×10^-3 mm^2/s,which provided the best combination of sensitivity(97.6%)and specificity(94.3%),the area under the ROC curve was 0.92±0.32,corresponding to histopathological findings,the Kappa value of the repeat measurements was 0.91 for SFT/HPC and 0.87 for meningioma,which indicated a good concordance of the results.Conclusions:MinADC value can be used as a quantitative tool to distinguish intracranial SFT/HPC from meningioma and improve the accuracy of preoperative diagnosis.