目的 通过对老年代谢综合征患者进行弥散张量成像（diffusion tensor imaging，DTI）研究，探讨DTI上胼胝体各向异性异常对老年早期认知功能障碍的诊断价值。 方法 对10对老年代谢综合征患者和正常老年人，进行脑磁共振弥散张量检查，对兴趣区（ROI）测定各向异性分数（FA）值和表观弥散系数（ADC）值，并与韦氏神经心理学测验结果进行比较。 结果 老年代谢综合征患者，胼胝体膝部、压部的FA值明显低于正常对照组，而ADC值高于正常对照组。胼胝体压部FA值与言语商、操作商、记忆商呈正相关（P＜0. 05）。 结论 老年代谢综合征患者有胼胝体膝部、压部的各向异性下降，反映了脑白质纤维结构的破坏，DTI为认知功能障碍脑内微观结构改变提供了客观依据，胼胝体压部FA值可作为判断认知功能损害的参考指标。

Objective To explore the diagnostic value between the corpus callosum measurement of

the fraction anisotropy of diffusion tensor imaging (DTD) and the early changes of cognition function in elderly metabolic syndrome. Methods Ten elderly metabolic syndrome and 10 normal aging elderly matched with age and tender underwent the measure of DTI, fraction anisotropy (FA) and the apparent diffusion coefficient (ADC) on regions of interest and neuropsychological tests. Results The FA on anterior and posterior corpus callosum was lower in the metabolic syndrome group than in control subjects. The ADC on anterior and posterior corpus callosum was higher in the metabolic syndrome group than in control. The FA on posterior corpus callosum had positive correlation with performance intelligence quotient，verbal intelligence quotient and memery quotient (P＜0. 05). Conclusions The decreased fraction anisotropy on anterior and posterior corpus callosum in metabolic syndrome can reflect the destruction of white matter fiber, which prove cognitive impairment in the microstructural changes. The measurement of the fraction anisotropy on posterior corpus callosum is helpful in diagnosis of cognitive dysfunction.