弥散张量成像与老年人认知功能的相关性

目的：研究老年人认知功能与MRI弥散张量成像（DTI）参数的相关性。方法：年龄〉60岁的老年人43例,按其认知功能量表评分[简易智能状态量表（MMSE）、临床痴呆量表（CDR）、总体衰退量表（GDS）和日常生活活动能力量表（ADL）]分为认知功能正常组、轻度认知功能障碍组和阿尔茨海默病3组,比较各组间头颅MRI部分各向异性（FA）和表观弥散系数（ADC）值是否具有差异,寻找与认知功能相关的颅内结构。结果：左侧颞叶、胼胝体膝部、压部的FA和ADC值,以及右侧额叶、双侧半卵圆中心的ADC值组间差异有统计学意义（P〈0.05）。FA值随认知功能减退而降低;而ADC值随认知功能减退而增高。额叶、颞叶、半卵圆中心和胼胝体等部位的DTI参数与常用的MMSE、CDR、GDS、ADL评分显著相关（P〈0.05）。结论：MRIDTI参数与老年人认知功能水平显著相关。

The Correlation between Diffusion Tensor Imaging and Cognitive Function in Elders

To investigate the correlation between diffusion tensor imaging（DTI） parameters and cognitive function in elders. Methods： In this study, 43 participants aged over 60 years old were recruited. They were divided into control subjects, mild cognitive impairment（MCI） and Alzheimer’s disease（AD） according to their different cognitive function. Fractional anisotropy（FA） and apparent diffusion coefficient（ADC） values were compared among the three groups to determine whether FA and ADC values were different in the elders with different cognitive function and which parts in cerebrum were correlated with the scores of neuropsychology tests. Results： It was found that there were significant differences of both FA and ADC values in left temporal, the genu and the splenium of corpus callosum, and ADC values in right frontal and both sides of semi-oval centre （P〈0.05） among the three groups of different cognitive function. FA values decreased and ADC values elevated in AD and MCI groups. Pearson correlation analysis showed that DTI parameters in several parts in cerebrum such as frontal, temporal lobe, semi-oval centre, and corpus callosum were correlated with the scores of neuropsychology tests（P〈0.05）. Conclusion： There was a notable correlation between DTI parameters and cognitive function in elders.