幕上胶质瘤的扩散张量纤维束成像的初步探讨

Pilost study of supratentorial gliomas by diffusion tensor magnetic resonance imaging and fiber tracking

【目的】应用扩散张量成像(diffusion tensor imaging,DTI)技术对颅内胶质瘤进行研究,探计DTI对颅内胶质瘤的诊断价值。【方法】应用3.0T MR对15例胶质瘤的病人术前行常规MRI及DTI检查,经后处理得到彩色FA图及脑白质纤维束图,测量肿瘤实质部分、周围胼胝体区及正常白质区的FA值,并观察肿瘤与白质纤维束的关系。对手术标本进行肿瘤细胞密度的检测并评价FA值与细胞密度的关系。【结果】15例病人均显示纤维束破坏;正常白质区与肿瘤实质部分的平均FA值有显著性差异;FA值与细胞的密度成正相关(r=0.71,P<0.05)。【结论】术前测量FA值及纤维束成像可预测肿瘤的恶性程度,直观地显示纤维束受累的情况,有助于手术方案的制定或指导定位活检及预后的判断。

[Objective] To study the diagnostic valve of diffusion tensor imaging （DTI） and white matter tractography for suprat-entorial gliomas. [Methods] In this srudy, diffusion-tensor imaging was peiformed preoperatively in 15 patients with intraemnial neoplasms. Fractional anisotropy （FA） was measured and analyzed within tumor, normal white matter and corpus callosum. White matter tractography was done to evaluate the relationship between tumors and white matter. Cell density was examined using specimens obtained from biopsies. Correlation between FA values and cell density was also evaluated. [Results] All patients showed white matter involved. The mean FA value significantly differed between normal brain regions and glioma lesions. Postive correlation was observed between FA value and cell density （r = 0.71, P 〈 O. 05）. [ Conclusions] Our results suggest that FA valve of gliomas as determined by DTI prior to surgery is a good predictor of cell density. DTI and white matter tractography is useful in deciding the surgical strategy or selecting the site of stereotactic biopsy.