采用MR灌注成像评价脑胶质瘤微血管管径的价值  

In vivo imaging of vessel size in glioma by using MR perfusion imaging

作　　者：康厚艺[1] 陈金华[1] 谭勇[1] 肖华亮[2] 方三高[2] 陈晓[1] 李晓光[1] Wang Sumei 张伟国[1] 

机构地区：[1]第三军医大学大坪医院野战外科研究所放射科,重庆400042 [2]第三军医大学大坪医院野战外科研究所病理科,重庆400042 [3]宾夕法尼亚大学医院放射科

出　　处：《中华放射学杂志》2014年第9期745-749,共5页Chinese Journal of Radiology

基　　金：国家自然科学基金（81271626）;重庆市自然科学基金（cstc2012jjb10028）

摘　　要：目的 评价采用MR灌注加权成像（PWI）测量胶质瘤微血管管径的有效性及准确性,并初步探讨胶质瘤血管管径指数（VSI）在胶质瘤分级中的作用.方法 搜集脑胶质瘤患者28例,其中低级别肿瘤（WHOⅡ级）9例、高级别肿瘤19例[间变性胶质瘤（WHOⅢ级）6例和胶质母细胞瘤（WHOⅣ级）13例].所有患者行MR梯度回波-自旋回波动态磁敏感对比增强灌注序列扫描,得到VSI彩图,用热点法测量肿瘤最大灌注区微血管管径大小.将VSI值与组织学测量的微血管管腔的内径（包括长径及短径）行Pearson相关性分析,对不同级别胶质瘤的VSI值和组织学管径行单因素方差分析.应用ROC曲线评估VSI值鉴别高、低级别胶质瘤的价值.结果 PWI测量肿瘤VSI最大值为（130.6±58.9）μm,平均值为（106.2±46.5） μm;组织学测量微血管长径为（34.2±13.6） μm,短径为（24.0±11.9）μm.VSI平均值与短径（r=0.808）、长径（r=0.805）,VSI最大值与短径（r=0.777）、长径（r=0.801）间均呈明显正相关（P值均＜0.01）.Ⅱ、Ⅲ和Ⅳ级胶质瘤的VSI平均值分别为（44.0±19.1）、（112.3±24.0）、（138.8±23.2） μm,长径分别为（18.9±5.1）、（33.3±10.1）、（43.5± 10.2） μan,短径分别为（10.0±2.4）、（21.9±8.3）、（33.7±7.2）μm,不同级别间差异均有统计学意义（F值分别为45.33、18.81、33.45,P值均＜0.01）.ROC曲线分析显示VSI平均值取临界值81.1 μm,VSI最大值取临界值109.0 μm时,其鉴别高、低级别胶质瘤的敏感度及特异度均可达100％.结论 VSI和组织学方法评估血管管径大小有很好的一致性,VSI方法可术前定量评估胶质瘤微血管结构的改变,将有可能更准确预测胶质瘤分级和预后.Objective To assess the validity and accuracy of the vessel size index（VSI） derived from magnetic resonance perfusion imaging （MR-PWI） and to explore the correlation between VSI and glioma grading.Methods Twenty-eight patients with glioma confirmed by pathology （WHO Ⅱ in 9 cases,WHO Ⅲ in 6 cases,and WHO Ⅳ in 13 cases） undertook MRI on 1.5 T scanner.VSI maps were generated from multi gradient-echo spin-echo sequence of MRI dynamic susceptibility contrast perfusion imaging.Hot spot method was used to measure vessel size in the area of the highest perfusion.Cerebral microvascular caliber was measured by immunohistochemistry ex vivo.Pearson correlation analysis was used to assess the correlation between the MRI findings and histology.One-way ANOVA was used to compare vessel size and VSI value among different grades of gliomas.ROC analysis was used to evaluate VSI values in distinguishing high-grade glioma from low-grade.Results MR-VSI showed that the maximal value of microvascular diameters was （130.6± 58.9） μm,average value was （106.2±46.5） μm.Histology showed that the long diameter of glioma microvessels was （34.2± 13.6） μm,short diameter was （24.0± 11.9）μm.There was strong correlation between VSIMRI average values and short diameters or long diameters（r=0.808,0.805,respectively; P＜0.01）.And also there was positive correlation between VSI maximal values and short diameters or long diameters（r=0.777,0.801,respectively; P＜ 0.01）.The VSI average values for grade Ⅱ,Ⅲ or Ⅳ glioma were （44.0± 19.1）,（112.3±24.0）,（138.8±23.2）μm,respectively.The long diameters were （18.93±5.11）,（33.27±10.14）,（43.54±10.16）μm,and short diameters were （10.0±2.4）,（21.9±8.3）,（33.7± 7.2） μm,respectively.All revealed significant difference（F=45.33,18.81,33.45,P＜0.01）.ROC analysis revealed the optimal cutoff value of 81.1 μm （mean VSI） and 109.0 μm （maximal VSI） for distinguishing the high-grade gliomas from low-grade,the sens

关 键 词：神经胶质瘤 磁共振成像 微血管 

分 类 号：R739.41[医药卫生—肿瘤]