脑白质稀疏症的MR弥散张量成像研究  

DTI study of leukoaraiosis

作　　者：钟维佳[1] 赵建农[1] 谢微波[1] 陈维娟[1] 

机构地区：[1]重庆医科大学附属第二医院放射科,重庆400010

出　　处：《重庆医科大学学报》2008年第2期198-202,共5页Journal of Chongqing Medical University

摘　　要：目的:探讨脑白质稀疏症(Leukoaraiosis,LA)在弥散张量成像(Diffusion tensor imaging,DTI)的表现,及LA病灶弥散、各向异性的改变。方法:对30例LA患者及20例正常人行弥散张量成像,测定LA病灶以病灶及周围看似正常白质(Normalappearing white matter,NAWM)的平均弥散系数(Average diffusion coefficient,ADCav)和部分各向异性(Fraction anisotropy,FA)值。通过统计学比较来反映病灶同病灶周围NAWM之间的弥散及各向异性差别。通过LA病灶周围NAWM与年龄匹配正常对照组相应部位的脑白质参数比较,来反应这些参数之间是否存在差异。结果:LA病灶在ADCav图上表现为较高信号,与周围NAWM比较信号明显升高。而在FA图上表现为较低信号,与NAWM比较信号明显降低。LA病灶的ADCav及FA值与周围NAWM相应参数之间存在显著差异(P<0.05);与正常对照组相应部位相应参数比较,LA病灶周围NAWM的ADCav及FA值也存在差异(P<0.05)。结论:DTI可以定量反映脑白质稀疏症病灶的弥散及各项异性改变,甚至可以在病程早期反映这种改变。Objective：To discuss the presentation of leukoaraiosis（LA） by diffusion tonsor imaging（DTI） and the changes of LA lesion diffusivity and anisotropy. Methods：A total of 30 cases of LA and 20 normal cases with matched age underwent conventional MRI scan and DTI. ADCav（average diffusion coefficient） and FA（fraction anisotropy） values were measured in the LA lesions,the normal appearing white matter（ NAWM ）around the LA lesions and the corresponding normal white matter in the normal group. All parameters were compared statistically to reveal whether there was difference between the lesions and the NAWMs. And those parameters of the NAWMs and corresponding regions of normal white matter in control group were also compared for the difference. Results：LA lesions presented to be high signal on ADC, map and low signal on FA map. Compared with NAWM in the LA cases,ADCav value of the LA lesion was higher,FA value was lower（P〈0.05） and the difference was significant. Both ADCav and FA values in the corresponding white matter of the control group showed significant difference from the values in the NAWMs（P〈0.05） Conclusion：DTI reflects the quantitative changes of LA lesion＇s diffusivity and anisotropy,even in the early stage.

关 键 词：脑白质稀疏症 弥散张量成像 

分 类 号：R814.42[医药卫生—影像医学与核医学]