扩散峰度成像对桥小脑角影像表现不典型的前庭神经鞘瘤和脑膜瘤的鉴别价值

The Role of Diffusion Kurtosis Imaging in Differentiating Vestibular Schwannomas from Meningiomas with Atypical Manifestation in the Cerebellopontine Angle

目的评估扩散峰度成像(DKI)在鉴别桥小脑角影像表现不典型的前庭神经鞘瘤(VS)与脑膜瘤中的价值。方法前瞻性纳入52例桥小脑角影像表现不典型的VS和脑膜瘤患者。在术前对所有患者行DKI扫描。半自动勾画肿瘤的实性区域获得肿瘤的DKI参数值,包括平均峰度值(MK),轴向峰度值(AK),径向峰度值(RK),各向异性分数(FA)和平均扩散系数(MD)。采用双样本t检验比较VS和脑膜瘤间的DKI参数值,应用单因素方差分析(ANOVA)比较VS和脑膜瘤亚型间的DKI参数值。运用受试者工作特征曲线(ROC)分析DKI参数在鉴别两组的价值。结果VS的MK,AK,RK,FA值显著低于脑膜瘤,MD值显著高于脑膜瘤(P值均<0.05)。VS和各亚型脑膜瘤之间的峰度值存在显著性差异(P≤0.001)。MK,AK和RK值鉴别VS和脑膜瘤的曲线下面积(AUC)分别为0.971,0.969和0.972,准确率分别为90.39%,90.39%和92.31%,其诊断效能显著优于FA和MD值(P值均<0.05)。结论DKI有助于鉴别桥小脑角影像表现不典型的VS和脑膜瘤,峰度值可以作为区分它们的最佳参数。

Objective To assess the values of diffusion kurtosis imaging(DKI)in the differentiation of vestibular schwannomas(VS)from meningiomas with atypical manifestation in cerebellopontine angle.Methods Fifty-two VS and meningioma with atypical manifestation in the cerebellopontine angle were prospectively enrolled.All patients underwent DKI exam before surgery.Mean kurtosis(MK),radial kurtosis(RK),axial kurtosis(AK),fractional anisotropy(FA)and mean diffusivity(MD)were semi-automatically obtained in the solid components of tumors.The two-sample t-test was used to compare the values of DKI parameters between the two groups,and analysis of variance(ANOVA)was used to compare the DKI parameters between VS and meningioma subtypes.The receiver operating curve(ROC)analysis was used to evaluate the value of DKI parameters in differential diagnosis between the two groups.Results MK,RK,AK,and FA were significantly lower in VS than in meningiomas,MD were significantly higher in VS than in meningiomas(all P<0.05).The kurtosis values of VS and meningioma subtypes were significantly different(P≤0.001).The area under the ROC curve of MK,AK and RK values were 0.971,0.969 and 0.972,and the accuracy was 90.39%,90.39%and 92.31%,respectively.The diagnostic efficacy of MK,RK and AK values was significantly better than that of FA and MD values(P<0.05).Conclusion DKI is helpful to distinguish VS and meningiomas with atypical manifestation in cerebellopontine angle.Kurtosis values may serve as optimal parameters for discriminating them.