王建利 谢敬霞 100083 北京医科大学第三医院放射科 中华放射学杂志 1999 0 33 10


    关键词：脑；磁共振成像；扩散；各向异性 期刊 zhfsxzz 0 中枢神经系统放射学 fur -->


    

【摘要】 目的 定量地研究正常成人脑组织内水分子扩散的各向异性。方法 利用多层面、多轴向平面回波的磁共振扩散加权成像分别对体外的生理盐水和23例健康成人脑组织的多个解剖部位进行水分子扩散的定量研究，包括表观扩散系数(ADC)及其变异系数(CV)等。结果 体外的生理盐水的扩散系数在不同扩散梯度方向上无显著性差异，表现为扩散的各向同性。而除丘脑外的正常脑灰质团块(尾状核头部和豆状核)及白质(半卵圆中心、内囊后肢、胼胝体膝部和压部)的ADC值在不同扩散梯度方向上存在显著性差异(P≤0.05)。不同脑组织部位扩散的各向异性程度差别很大。侧脑室体部的脑脊液也有扩散的各向异性。结论 扩散的各向异性在人脑组织中普遍存在。定量地研究脑组织内的扩散，应该描述其扩散的方向性。

Anisotropic waterdiffusion in human brain

WANG Jianli, XIE Jingxia.

    Department of Radiology, the Third Hospital of Beijing Medical University, Beijing 100083

【 Abstract 】 Objective To quantitatively investigate theanisotropic water diffusion in normal human brain. Methods Apparent diffusion coefficients(ADC) and their coefficients of variation (CV) were calculated in natural saline and 23normal human brains from multisection, multidirection echo-planar diffusion-weightedimages. Results No statistically significant difference in diffusioncoefficients in different diffusion gradient directions was found in natural saline.However, significant differences in ADC in different diffusion gradients were found withinnormal human brain parenchyma, which including caudate nucleus, lentiform nucleus, centrum semiovale, posterior limb of internal capsule, and corpus callosum, except the thalamus.Diffusion anisotropy varied significantly among different anatomic regions. Anisotropicdiffusion was also found in cerebrospinal fluid in the body of lateral ventricle. Conclusions Diffusion anisotropy is aprevalent phenomenon in human brain. Quantitative characterization of water diffusion inbrain tissues should include directional information.

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