磁共振动态对比增强联合扩散峰度成像在脑胶质瘤分级中的价值分析

Value analysis of dynamic contrast enhanced magnetic resonance imaging combined with diffusion kurtosis imaging in grading of glioma

目的:分析磁共振动态对比增强(dynamic contrast enhanced MRI,DCE-MRI)联合扩散峰度成像(diffusion kurtosis imaging,DKI)在脑胶质瘤分级中的临床价值,为鉴别诊断高级别脑胶质瘤和低级别脑胶质瘤寻找一种敏感方法。方法:将47例脑胶质瘤患者根据术后病理组织检查分为高级别脑胶质瘤组(n=25例)和低级别脑胶质瘤组(n=22例),所有患者均行DCE-MRI和DKI检查,比较2组患者转运常数(Ktrans)、血管外细胞外容积分数(Ve)、速率常数(Kep)等DCE-MRI参数和平均扩散峰度(mean kurtosis,MK)、平均扩散系数(mean diffusivity,MD)和各向异性分数(fractional anisotropy,FA)及相对扩散各向异性分数(ratio of FA,rFA)、相对平均扩散系数(ratio of MD,rMD)、相对平均扩散峰度(ratio of MK,rMK)等DKI参数。采用SPSS 19.0统计学软件进行数据分析,2组参数值比较采用独立样本t检验。采用ROC曲线分析各参数鉴别诊断高、低级别脑胶质瘤的敏感度、特异度和曲线下面积(area under curve,AUC)。结果:高级别脑胶质瘤组Ktrans、Ve值均明显高于低级别脑胶质瘤组(P<0.05),而2组Kep值比较无显著性差异(P>0.05);高级别脑胶质瘤组MK及rMK均明显高于低级别脑胶质瘤组(P<0.05),而2组MD、FA、rMD、rFA比较无显著性差异(P>0.05);DCE-MRI联合DKI诊断高级别脑胶质瘤的AUC、敏感度、特异度均高于DCE-MRI、DKI单一诊断。结论:DCE-MRI (Ktrans)联合DKI(rMK)在脑胶质瘤分级中具有较高的临床价值。

Objective To analyze the clinical value of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) combined with diffusion kurtosis imaging (DKI) in grading of glioma so as to find a sensitive method to distinguish high grade glioma and low grade glioma. Methods Totally 47 patients with glioma were divided into a high-grade glioma group (n=25) and a low-grade glioma group (n=22) according to postoperative histopathologic examination, and all the patients were detected by DCE-MRI and DKI. The DCE-MRI parameters such as Ktrans, Ve and Kep as well as DKI parameters such as MK, MD, FA, rFA, rMD and rMK of the two groups were compared. The values of the parameters and combined diagnosis of high-grade glioma were analyzed by ROC curve. All the data were analyzed by SPSS 19.0 statistical software, and independent sample t test was used to compare the parameter values of the two groups. ROC curve was used to analyze the sensitivity, specificity and area under curve (AUC) of various parameters in the differential diagnosis of high-grade and low-level gliomas. Results The Ktrans and Ve values of the high-grade glioma group were significantly higher than those of the low-grade glioma group (P<0.05), while there was no significant difference in Kep values between the two groups (P>0.05). The MK and rMK of the high-grade glioma group were significantly higher than those of the low-grade glioma group (P<0.05), while there was no significant difference between the two groups about MD, FA, rMD and rFA (P>0.05). The AUC, sensitivity and specificity in diagnosing high-level brain glioma by DCE-MRI combined with DKI were all higher than those by DCE-MRI or DKI. Conclusion DCE-MRI parameters (Ktrans) combined with DKI parameters (rMK) has a high clinical value in grading of glioma.