Delineation of relationship between brain tumor and the white matter tracts by means of 3-dimenitional anisotropy contrast imaging and diffusion tensor analysis

通过三维各向异性对比成像和扩散张量分析描绘脑肿瘤与白质束之间的关系

基本信息

批准号：
11670862
负责人：
TAKAHASHI Shoki
金额：
$ 1.79万
依托单位：
Tohoku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

项目摘要

PURPOSE : To evalutate the usefulness of 3-dimentional anisotropy contrast (3DAC) imaging and diffusion tensor analysis for delineation of relationship between brain tumor and the white matter tracts, we applied these technique to 5 normal volunteers (first year) and 19 patients with a supratentorial brain tumor.METHODS : 3DAC imaging was performed by synthesizing color-coded diffusion-weighted images (DWI) which were obtained by applying motion probing gradient (MPG) in 3-orthogonal directions. Diffusion tensor analysis was performed using DWIs obtained by applying MPG in 6 different directions. Using this data sets, we obtained images of fractional anisotorpy (FA), apparent diffusion coefficient (ADC) trace and diffusion eigenvalues. The FA is one of the indicies representing diffusion anisotorpy.RESULTS :1) Results of 3DAC imagingIn the analysis of the normal subjects, the 3DAC images delineated the white matter tracts clearly in all cases. However, the images tended to be poor in i … More nfratentorial region due to susceptiblity artifacts, which made it almost impossible to evaluation of the fiber tracts in some cases.In the cases with brain tumor, we evaluated the relationship between a tumor and the pyramidal tract by 3DAC images. In all cases, 3DAC images could clearly show the relationship ; the tumor just compressed the tracts or the tumor/perifocal edema involved the tracts.2) Results of diffusion tensor analysisAt first, we compared the accuracy of the measurement of diffusion anisotropy between diffusion tensor analysis (FA) and conventional 3-orthogonal diffusion imaging (FA-3) in 5 normal subjects and 4 patients with brain tumor. In the analysis of healthy subjects, FA-3 was significantly more asymmetric than FA.In one case with a brain tumor compressing the pyramidal tract, FA-3 showed markedly underestimated, which led erroneous conclusion.Then, we investigated the diffusion characteristics of the pyramidal tract in cases with brain tumor. The FA, ADC trace and eigenvalues of the pyramidal tracts were measured. These indices reflected condition of pyramidal tract, being compressed and/or being T2-high. Estimation of eigenvalues, in addition to the FA and the trace, should provide more detailed information.CONCLUSION3DAC imaging and diffusion tensor analysis may provide additional useful information about the white matter tracts, which may be helpful for surgical planning of brain tumors. Less

目的：为了评估 3 维各向异性对比 (3DAC) 成像和扩散张量分析在描绘脑肿瘤和白质束之间关系方面的有用性，我们将这些技术应用于 5 名正常志愿者（第一年）和 19 名患有脑肿瘤的患者。方法：通过合成颜色编码的扩散加权图像（DWI）进行3DAC成像，这些图像是通过应用运动探测梯度获得的使用在 6 个不同方向应用 MPG 获得的 DWI 进行扩散张量分析。使用该数据集，我们获得了分数各向异性 (FA)、表观扩散系数 (ADC) 迹线和扩散特征值的图像。 FA是代表扩散各向异性的指标之一。结果：1）3DAC成像结果在对正常受试者的分析中，3DAC图像描绘了在所有情况下，白质束都清晰可见，但是，由于磁敏感伪影，幕下区域的图像往往很差，这使得在某些情况下几乎不可能评估纤维束。在脑肿瘤的情况下，我们通过 3DAC 图像评估肿瘤与锥体束之间的关系在所有情况下，3DAC 图像都可以清楚地显示肿瘤仅压迫锥体束或涉及锥体束的肿瘤/灶周水肿。 2）扩散张量分析结果首先，我们比较了扩散张量分析（FA）和传统3-正交扩散成像（FA-3）在5名正常受试者和4名脑肿瘤患者中测量扩散各向异性的准确性。在对健康受试者的分析中，FA-3 的不对称性明显高于 FA。在 1 例脑肿瘤压迫锥体束的病例中，FA-3 表现出明显低估，从而导致错误结论。然后，我们研究了脑肿瘤病例中锥体束的扩散特征，测量了锥体束的FA、ADC迹线和特征值，这些指标反映了锥体束的状况、被压缩和/或被T2。 -除了 FA 和迹线之外，特征值的高估计还应提供更详细的信息。结论 3DAC 成像和扩散张量分析可能提供有关白质束的其他有用信息，这可能有助于脑肿瘤的手术计划。