摘要
目的:利用DTI探讨急性缺血性脑卒中病人大脑白质纤维束各向异性特征和皮质脊髓束受损与肌力的关系。方法:对9例正常被试和9例急性期缺血性脑卒中病人进行常规MR T1WI、T2WI和DTI检查,对数据进行离线后处理,采用dTV.II软件处理,获得FA图及方向编码彩色(DEC)图,并重建双侧皮质脊髓束3D纤维束图。结果:在正常组双侧白质纤维束FA值无明显差异,重建FA值图与方向编码彩色图可显示大部分主要的白质纤维束。在脑卒中病人组梗死区FA值显著低于健侧,两侧相比差异有显著性意义(t=4.570,P<0.001)。病变侧皮质脊髓束受压、变形、移位、部分断裂,皮质脊髓束受累情况与肌力有相关性(rs=0.888,P<0.05)。结论:DTI可显示脑内白质纤维束的走行及分布,为大脑白质纤维束的研究开辟了新的广阔领域。DTI FA值图及DEC图可以显示卒中病人梗死区白质纤维的方向与各向异性程度。3D纤维束图可以更立体直观的显示锥体束状况,有利于探讨皮质脊髓束损伤程度与肌力的关系,对临床及判断预后有重要价值。
Objective：To study the diffusion anisotropic features of white matter fibers of acute cerebral ischemic stroke patients by MR diffusion tensor imaging （DTI）. To evaluate the relationship between the impairment degree of cortical spinal tract（CST） and muscular strength. Methods：9 patients with acute cerebral ischemic stroke and 9 volunteers were performed MR T1WI,T2WI and DTI. For imaging processing, fiber tracking with the software of DTV-Ⅱ , fractional anisotropy（FA） maps, directionally encoded color maps and 3D tractography of bilateral CST of all patients were created. Results： In normal volunteers group, measurements in white matter regions were not significantly different. Reconstruction FA images and DEC maps can display main white fibers. In stroke patients group, The FA value in infarct area of white matter was significant lower titan thst in normal hemisphere （paired test, t = 4.570, P 〈 0.001）. DTI shows that the CST were compression, displacement, transloeation, and partial break. The pathological change in ill side of CST is related with muscular strength of contralateral hand （ rs = 0. 888, P 〈 0.05 ）. Conclusion： DTI can precisely showed the orientation and distribution of cerebral white matter fiber tracts, opening a new field for researching cerebral white matter fiber in vivo. DTI FA maps and DEC maps displayed the orientation and anisotropy of white matter fiber in infarct area. 3D fiher tract maps could display the status of pyramidal tract more stereotacticly, then has important value to clinical management and prognesis.
出处
《医学影像学杂志》
2007年第1期23-27,共5页
Journal of Medical Imaging
关键词
脑卒中
弥散张量成像
纤维束成像
磁共振成像
Cerebral stroke
Diffusion tensor imaging
Tractograpby
Magnetic resonance imaging
