脑胶质瘤MR灌注成像与肿瘤微血管特征的相关性研究

Relationship between MR Perfusion Weighted Imaging Features and Tumorous Microvessels Characteristics in Cerebral Glioma

目的探讨胶质瘤MR灌注血容量变化与肿瘤微血管密度、微血管形态变化的关系。资料与方法对49例胶质瘤患者行动态磁敏感增强(dynamic susceptibility contrast,DSC)灌注扫描,测定胶质瘤的最大相对脑血容灌注值(maximum relative cerebral blood volume,rCBVmax)。采用Mann-Whitney U秩和检验比较不同级别及类型胶质瘤的灌注差异,并对病理标本行CD34免疫组织化学染色,观测肿瘤微血管密度及管腔大小,二元线性回归分析rCBVmax值与微血管密度及微血管腔径的关系。结果高、低级别胶质瘤间rCBVmax值存在显著性差异,二元线性回归分析显示该值不仅与微血管密度有关,而且与管腔径线也有明显的关系,且肿瘤微血管腔径大小对于rCBV-max值的影响更大,回归方程为Y=1.047+0.219X1+0.055X2(F=10.33,P<0.01;R=0.557)。结论 DSC灌注的rCBVmax值与肿瘤微血管特征关系密切,胶质瘤微血管密度和微血管腔径变化是MR灌注血容量变化的重要病理学基础。

Objective To explore the relationship between the blood volume on MR perfusion weighted imaging and the tumorous microvessel in cerebral glioma.Materials and Methods Forty-nine patients with glioma underwent DSC perfusion-weighted imaging to measure the maximum relative cerebral blood volume.Mann-Whitney U test was used to identify the perfusion difference in different grade and type of glioma.Furthermore,all pathological specimens were immunohistochemistry stained to measured microvessel density and caliber of tumor.Binary linear regression analysis was performed to find relationship between tumorous microvessel and rCBVmax.Results The rCBVmax has significant difference between high-grade and low-grade glioma.Binary linear regression analysis showed that rCBVmax not only related with microvessel density but also with microvascular caliber,and the microvessel caliber exerted greater impact on the rCBVmax.The equation was Y=1.047＋0.219X1＋0.055X2（F=10.33,P0.01;R=0.557）.Conclusion There were close relationship between rCBVmax of DSC perfusion weighted imaging and tumorous microvessels and that changes of glioma microvessel density and microvascular caliber might be important pathological foundation for MR perfusion blood volume change.