摘要
目的通过使用磁共振弥散张量成像(DTI)对健康成年人的脑白质纤维束进行检测,探讨DTI及部分各向异性值(FA)对评价年龄引起的脑白质变化的价值.方法对30例健康志愿者(青年组20～30岁,老年组60～83岁,各15例)进行脑部MR横轴位检查,扫描序列包括T1Flair、T2WI、FLAIR、DWI、DTI.在大脑胼胝体膝、压部、内囊膝部及后肢、视辐射、额叶白质及丘脑选定兴趣区(ROI),测量其FA值并做统计学分析.结果青年组胼胝体膝部及压部、内囊膝部、视辐射、额叶白质的FA值分别为:(0.70±0.05)、(0.70±0.05)、(0.63±0.04)、(0.53±0.05)、(0.43±0.06),老年组相应ROI的FA值分别为:(0.62±0.09)、(0.66±0.07)、(0.57±0.07)、(0.38±0.06)、(0.38±0.07),两组差异有统计学意义(P＜0.05);内囊后肢及丘脑FA值差异无统计学意义.结论DTI对评价脑白质纤维束的密度及有序性有价值,FA值能反映两组不同年龄人群脑白质的生理状态.
Objective To explore the evaluation of FA（fractional anisotropy） in assessing the age-related physiologic changes of white matter in normal adults by use of diffuse tensor MR imaging （DTI） Methods Thirty healthy subjects（20-30 y, 15 subjects ;60-83 y, 15 subjects） underwent conventional MRI and diffusion-tensor MR imaging. DTI was performed using single shot SE-EPI sequence. The b value was 1000 s·mm^2. The diffusion was measured along 13 directions. FA was measured in genu and splenium of corpus callosum, the knee and posterior limb of internal capsule, optic radiations, frontal white matter, thalamus respectively. Statistical analysis was performed. Results The FA values of young group in genu and splenium of corpus callosum, the knee and posterior limb of internal capsule, optic radiations, frontal white matter, thalamus were（0.70±0.05）,（0.70±0.05）,（0.63±0.04）, （0.63±0.02）,（0.53±0.05）,（0.43±0.06）, （0.27±0.02） respectively. The FA values of older group in genu and splenium of corpus callosum, the knee and posterior limb of internal capsule, optic radiations, frontal white matter, thalamus were （0.62±0.09） ,（0.66±0.07） ,（0.57±0.07）,（0.61±0.04）,（0.38±0.06）, （0.38±0.07）, （0.27±0.03）. A significant FA declines of older group in genu and splenium of corpus callosurn , the knee of internal capsule, optic radiations, frontal white matter were found （P〈0.05）. The FA Value in posterior limb of internal capsule of older group was lower. But no significant difference was observed between two groups （P〉0.05）. There was no significant difference in FA between the left and right hemisphere（P〉0.05）. Conclusions DTI is valuable in assessing the directionality and density of white matter and can reflect the age-related physiological changes of white matter in vivo noninvasively.
出处
《中华老年医学杂志》
CAS
CSCD
北大核心
2005年第9期667-669,共3页
Chinese Journal of Geriatrics
基金
广东省自然科学基金资助项目粤科基办〔2002〕4号021154
