DWI联合DCE-MRI鉴别呈环形强化的脑GBM和感染性病变

Differentiation of cerebral glioblastoma and infectious lesions with ring-shape enhancement using diffusion-weighted imaging and dynamic contrast-enhanced magnetic resonance imaging

目的:探讨MR扩散加权成像(DWI)和3D肝脏容积快速采集(LAVA)序列动态对比增强(DCE)MRI扫描对颅内呈环形强化的胶质母细胞瘤(GBM)和感染性病变的鉴别诊断价值。方法:回顾性搜集2015年9月-2020年9月在本院经病理证实的23例脑GBM和17例颅内感染性病变(脑脓肿11例,结核瘤6例)患者的临床和MRI资料。所有患者在术前2周内行3.0T颅脑MRI扫描,扫描序列包括常规序列、对比增强T_(1)WI、DWI和LAVA序列DCE-MRI扫描。分别使用Firevoxel软件和GE Omni-Kinetics软件在每例患者的表观扩散系数(ADC)图和DCE图像中选取病灶最大层面于病灶内环形强化区域手动勾画ROI,测量并比较两组病变的ADC第一四分位数(ADC-P25)、容积转移常数(K_(trans))、血管外细胞外体积分数(V_(e))、增强曲线下初始面积(IAUGC)、速率常数(K_(ep))、血浆容积分数(V_(p))、达峰时间(TTP)和最大斜率(S_(MAX))测量值的差异。K_(trans)、V_(p)和IAUGC的组间比较采用独立样本t检验,ADC-P25、K_(ep)、V_(p)、TTP和S_(MAX)的组间比较采用Mann-Whitney U检验。对组间差异有统计学意义的参数,绘制其受试者工作曲线(ROC),评估单个参数和多参数联合后对GBM和感染性病变的鉴别诊断效能。将AUC<0.7、0.7~0.9和>0.9分别定义为具有低、中和高度诊断效能。结果:GBM的K_(trans)、IAUGC和S_(MAX)值均显著高于感染性病变,差异均有统计学意义(P=0.004、0.045、0.011),而ADC-P25显著低于感染性病变(P=0.042)。K_(trans)、ADC-P25和S_(MAX)值对两种病变均达到了中度以上的鉴别诊断效能,单一参数诊断效能最佳的是K_(trans),联合ADC-P25、K_(trans)和S_(MAX)三个参数的诊断效能最佳,其ROC曲线下面积、敏感度和特异度分别为0.967、0.900和1.000。结论:DWI和DCE-MRI定量及半定量参数对呈环形强化的GBM和感染性病变均具有一定的鉴别能力,两类参数联合可显著提高鉴别诊断效能。

Objective:This study was aimed to evaluate the diagnostic performance of diffusion-weighted imaging(DWI)and dynamic contrast-enhanced(DCE)-MRI to identify ring-shape enhanced GBM from ring-enhanced infectious lesions.Methods:Twenty-three patients with brain GBM and se-venteen patients with intracranial infectious lesions(eleven brain abscess and six tuberculomas)confirmed by pathology were retrospectively analyzed from September 2015 to September 2020.All patients underwent brain MRI examination at a 3.0T scanner within 2 weeks before surgery,and the sequences included T_(1)WI,T 2WI,contrast-enhanced T_(1)WI,DWI and 3D liver acquisition with volume acceleration(LAVA)DCE-MRI.The region of interest(ROI)of tumor and infectious lesion was ma-nually delineated on the largest layer of apparent diffusion coefficient(ADC)and DCE images using Firevoxel software and GE Omni-Kinetics software.Then,to compare the differences of ADC first quartile(ADC-P25),volume transfer constant(K_(trans)),volume of the extracellular extracellular space(V_(e)),initial area under the gadolinium curve(IAUGC),back flux constant(K_(ep)),plasma volume fraction(V_(p)),time to peak(TTP)and maximum rise slope(S_(MAX))between the two groups.K_(trans),IAUGC and V_(p)were compared between the two groups with use of the independent sample t-test,while ADC-P25,K_(ep),V_(e),TTP and S_(MAX)were compared between the two groups with use of the Mann-Whitney U-test.In addition,the area under the receiver operating characteristic(ROC)curve(AUC)was acquired to assess the differentiation diagnostic efficacy of the parameters with statistical difference.AUC<0.7,0.7~0.9 and>0.9 was named as low,median and high diagnostic efficacy.Results:K_(trans),IAUGC and S_(MAX)of the GBM group were significantly higher than those of the infectious lesions group,P-values respectively were 0.004,0.045 and 0.011,respectively;while ADC-P25 of the GBM group was significantly lower than that of the infectious lesions group(P=0.042).For the ROC analysis,both DWI and DCE-MRI parameters had good diagnostic performance for discriminating GBM from infectious lesions,the best diagnostic performance of single parameter was K_(trans),combined ADC-P25,K_(trans)and S_(MAX)had the best diagnostic performance,and its AUC,sensitivity and specificity were 0.967,0.900 and 1.000,respectively.Conclusion:Both DWI and DCE-MRI have ability to identify GBM from infectious lesions to a certain extent,and their combination can significantly improve the diagnosis efficiency.