中文摘要：

目的：探讨动态对比增强（DCE）-MRI在胶质母细胞瘤与脑转移瘤鉴别诊断中的应用价值。方法搜集经手术病理证实的20例高级别胶质瘤患者和20例脑转移瘤患者，术前行常规MRI及DCE-MRI扫描，分别在肿瘤实性部分最大截面及其周围区域选取3个ROI，经工作站后处理获得肿瘤的容积转运常数（Ktrans）、回流速率常数（Kep）及血管外细胞外容积分数（Ve）图，计算ROI内的Ktrans、Kep及Ve值，应用2个独立样本t检验比较两种肿瘤实质部分及其瘤周区域Ktrans、Kep及Ve值的差异；应用Pearson相关分析两种肿瘤实质部分Ktrans值与其瘤周区域Ktrans、Kep及Ve值的相关性。结果胶质母细胞瘤实性部分Ktrans、Kep及Ve值分别为（0.258±0.063）min－1、（0.398±0.082）min－1、0.632±0.084，转移瘤实性部分Ktrans、Kep及Ve值分别为（0.233±0.053）min－1、（0.357±0.042）min－1、0.672±0.113，两者间比较差异均无统计学意义（t值分别为－1.354、－1.982、1.276，P值均〉0.05）。胶质母细胞瘤瘤周区域Ktrans、Kep及Ve值分别为（0.093±0.032）min－1、（0.411±0.089）min－1、0.107±0.021，脑转移瘤瘤周区域Ktrans、Kep及Ve值分别为（0.033±0.010）min－1、（0.204±0.045）min－1、0.069±0.017，两者间比较差异具有统计学意义（t值分别为－7.978、－9.303、－6.203，P值均〈0.05）。胶质母细胞瘤实性部分Ktrans值与其周围区域的Ktrans、Kep及Ve值分别呈正相关（r值分别为0.759、0.464、0.651，P值均〈0.05），转移瘤实性部分Ktrans值与其周围区域的Ktrans、Kep及Ve值均无相关性（P值均〉0.05）。结论 DCE-MRI通过定量显示肿瘤毛细血管的通透性，可准确评估胶质母细胞瘤与脑转移瘤实性部分及瘤周区域的血脑屏障破坏的程度，在两种肿瘤的生物学特性评估及鉴别诊断中具有重要临床价值。

英文摘要：

Objective To investigate the value of dynamic contrast-enhanced MRI （DCE-MRI） in the differential diagnosis of glioblastoma and brain metastases. Methods Twenty patients with high grade gliomas and 20 cases patients with brain metastases proved by surgery and pathology were collected, and patients were examined with conventional MRI and DCE-MRI preoperatively. The ROIs were manually placed in solid parts of the tumors and their surrounding tissues to calculate Ktrans, Kep and Ve values. The Ktrans, Kep and Ve values differences for the solid part and surrounding tissues of the two brain tumors were compared by two independent sample t test. The correlation between Ktrans of the solid parts of the two brain tumors and Ktrans, Kep and Ve values of their surrounding tissues were studied by Pearson correlation analysis. Results The Ktrans, Kep and Ve values of glioblastoma were（0.258 ± 0.063）min-1,（0.398 ± 0.082）min-1, 0.632±0.084, the Ktrans, Kep and Ve values of brain metastases were（0.233±0.053）min-1,（0.357±0.042）min-1, 0.672±0.113. There were no significant differences between the glioblastoma and brain metastases for Ktrans, Kep and Ve values（t=-1.354,-1.982, 1.276, all P〉0.05）. The Ktrans, Kep and Ve values of surrounding tissues of glioblastoma were（0.093±0.032）min-1,（0.411±0.089）min-1, 0.107±0.021, the Ktrans, Kep and Ve values of＆amp;nbsp;surrounding tissues of brain metastases were（0.033±0.010）min-1,（0.204±0.045）min-1, 0.069±0.017. The Ktrans, Kep and Ve values of surrounding tissues between glioblastoma and brain metastases had significant difference （t=-7.978,-9.303,-6.203, all P〈0.05）. The Ktrans of glioblastoma were correlated with Ktrans, Kep and Ve values of their surrounding tissues （r=0.759, 0.464, 0.651, all P〈0.05）; The Ktrans values of brain metastases had no relationship with Ktrans, Kep and Ve values of their surrounding tissues （P〉0.05）. Conclusion The DCE-MRI can quantitatively display the microvascular permeability and