目的采用DTI和内侧颞叶萎缩(MTA)视觉评分评价轻度阿尔茨海默病(AD)患者脑白质微观结构改变及其MTA状况,并观察两者与认知功能的关系。方法运用DTI技术ROI测量方法对轻度AD患者23例(AD组)及正常老年人21名(NC组)的16个ROI进行平均扩散率(MD值)及部分FA值测量,同时用MTA视觉评分方法对MTA状况进行评估,采用独立样本t检验及典型相关分析观察两者与认知功能的关系。结果与NC组对比,AD组双侧海马旁回、双侧后扣带回、双侧下纵束及双侧下额枕束FA值明显减低,双侧海马旁回、双侧后扣带回、双侧下额枕束、左侧下纵束、在侧钩束MD值明显升高,MTA明显。脑白质部分区域DTI指数及舣侧MTA评分与认知功能相关。结论DTI能探测轻度AD患者脑白质微观结构异常;采用MTA评分方法可区分轻度AD与正常老年人;综合应用DTI技术及MTA评分厅法可为诊断轻度AI)提供更多辅助信息。
Objective To evaluate white matter integrity and medial temporal atrophy (MTA) in patients with mild Alzheimer disease (AD) by using DTI and MTA visual scale, and to investigate their relationship with cognitive function. Methods Forty-four subjects, including 23 mild probable AD (AD group) and 21 normal elders (NC group) were exam- ined using DTI technology and ROI method. Mean diffusivity (MD) and partial FA value were measured. Medial temporal lobe atrophy was assessed with MTA. Independent sample t-test and canonical correlation analysis were used. Results Compared to NC group, FA value in bilateral parahippocampal, posterior cingulate, inferior longitudinal fasciculus, inferi- or fronto-oecipital fascicles decreased significantly, while MD value of bilateral parahippocampal, posterior eingulate, infe- rior fronto-oecipital fascicles, and left inferior longitudinal fasciculus, left uncinate fasciculus increased significantly in AD group. Medial temporal lobe atrophy in mild AD group was obvious than in NC group. Part of DTI indexes and bilateral MTA scores correlated with cognitive performance. Conclusion DTI can detect white matter abnormalities in mild AD pa- tients, and MTA visual scale can distinguish mild AD from normal controls. Combination of these two methods can provide diagnostic information for mild AD.