脑肿瘤血流定量分析：动脉自旋标记与动态磁敏感加权对比增强磁共振成像的比较

Quantification of blood flow in brain tumors: comparison of arterial spin labeling and dynamic susceptibility-weighted contrast-enhanced MR imaging.

作者信息

Warmuth Carsten, Gunther Matthias, Zimmer Claus

机构信息

Department of Neuroradiology, Charité Medical School, Humboldt University of Berlin, Schumannstrasse 20-21, D-10098 Berlin, Germany.

出版信息

Radiology. 2003 Aug;228(2):523-32. doi: 10.1148/radiol.2282020409. Epub 2003 Jun 20.

DOI:10.1148/radiol.2282020409

PMID:12819338

Abstract

PURPOSE

To implement an arterial spin labeling technique that is feasible in routine examinations and to test the method and compare it with dynamic susceptibility-weighted contrast material-enhanced magnetic resonance (MR) imaging for evaluation of tumor blood flow (TBF) in patients with brain tumors.

MATERIALS AND METHODS

Thirty-six patients with histologically proven brain tumors were examined at 1.5 T. A second version of quantitative imaging of perfusion by using a single subtraction with addition of thin-section periodic saturation after inversion and a time delay (Q2TIPS) technique of pulsed arterial spin labeling in the multisection mode was implemented. After arterial spin labeling, a combined T2- and T2*-weighted first-pass bolus perfusion study (gadopentetate dimeglumine, 0.2 mmol/kg) was performed by using a double-echo echo-planar imaging sequence. In regions of interest, maps of absolute and relative cerebral blood flow were computed and analyzed with arterial spin labeling and dynamic susceptibility-weighted contrast-enhanced MR imaging, respectively.

RESULTS

Both techniques yielded the highest perfusion values in imaging of glioblastomas and the lowest values in imaging of two low-grade gliomas that both showed strong gadopentetate dimeglumine enhancement. There was a close linear correlation between dynamic susceptibility-weighted contrast-enhanced MR imaging and arterial spin labeling in the tumor region of interest (linear regression coefficient, R = 0.83; P <.005). Blood flow is underestimated with arterial spin labeling at low flow rates. High- and low-grade gliomas can be distinguished at the same level of significance with both methods. Absolute TBF is less important for tumor grading than is the ratio of TBF to age-dependent mean brain perfusion.

CONCLUSION

Arterial spin labeling is a suitable method for assessment of microvascular perfusion and allows distinction between high- and low-grade gliomas.

摘要

目的

实施一种在常规检查中可行的动脉自旋标记技术，并测试该方法，将其与动态磁敏感加权对比剂增强磁共振（MR）成像进行比较，以评估脑肿瘤患者的肿瘤血流（TBF）。

材料与方法

对36例经组织学证实的脑肿瘤患者进行1.5T磁共振检查。采用多层面模式下的脉冲动脉自旋标记技术，通过在反转后添加薄层周期性饱和及时间延迟的单次减法灌注定量成像（Q2TIPS）技术的第二版进行检查。动脉自旋标记后，使用双回波平面成像序列进行T2加权和T2*加权的首过团注灌注研究（钆喷酸葡胺，0.2 mmol/kg）。在感兴趣区域，分别利用动脉自旋标记和动态磁敏感加权对比增强MR成像计算并分析绝对和相对脑血流量图。

结果

两种技术在胶质母细胞瘤成像中均产生最高灌注值，而在两个均显示钆喷酸葡胺强烈增强的低级别胶质瘤成像中产生最低值。在感兴趣的肿瘤区域，动态磁敏感加权对比增强MR成像与动脉自旋标记之间存在密切的线性相关性（线性回归系数，R = 0.83；P <.005）。在低流速时，动脉自旋标记会低估血流量。两种方法在区分高级别和低级别胶质瘤方面具有相同水平的显著性。绝对TBF对肿瘤分级的重要性低于TBF与年龄相关的平均脑灌注的比值。