阿尔茨海默病和遗忘型轻度认知功能障碍扩散张量成像随访研究

Follow up Research of Diffusion Tensor Imaging in Patients with Alzheimer's Disease and Amnestic Mild Cognitive Impairment

目的探讨使用扩散张量成像(DTI)的各向异性分数(FA)随访阿尔茨海默病(AD)患者和遗忘型轻度认知功能障碍(aMCI)患者脑部变化。方法分别使用配对t检验比较15例AD患者和15例aMCI患者随访前后FA值差异、MMSE评分差异。将差异脑区平均FA值、FA变化值与MMSE评分、MMSE评分变化值进行Pearson相关分析。结果随访时AD患者和aMCI患者MMSE评分较前下降(AD:19.3±5.7,17.4±6.6;aMCI:27.0±1.6,26.4±1.8)(P值均>0.05)。随访时AD患者FA值在左侧后扣带回(0.53±0.06,0.51±0.06)、左侧楔前叶(0.35±0.05,0.34±0.06)、左侧海马旁回(0.21±0.02,0.20±0.02)、左侧额上回(0.33±0.03,0.31±0.03)和左侧颞中回(0.28±0.03,0.26±0.02)下降(P<0.001),aMCI患者FA值无明显差异。AD患者FA值差异脑区平均FA变化值与MMSE评分变化值未见明显相关。结论随时间延迟,AD患者FA值的下降提示更多脑回受累,FA值可能成为检测潜在白质损伤及随访的指标。

Objective The aim of this study is to follow up the changes of FA values in patients with Alzheimer’s disease(AD)and amnestic mild cognitive impairment(aMCI)using diffusion tensor imaging(DTI).Methods The FA values and MMSE scores(first time)were compared with FA values and MMSE scores(second time)respectively in patients with AD(n=15)and patients with aMCI(n=15)by using paired t test.Pearson correlations were analyzed between the average FA values,the changes of FA values,and MMSE scores,the changes of MMSE scores.Results Compared to patients with AD and aMCI(First time),MMSE scores decreased(AD:19.3±5.7,17.4±6.6;aMCI:27.0±1.6,26.4±1.8)(P>0.05).Significant decreases of FA values were found in patients with AD in left posterior cingulum(0.53±0.06,0.51±0.06),left precuneus(0.35±0.05,0.34±0.06),left parahippocampus(0.21±0.02,0.20±0.02),left superior frontal gyrus(0.33±0.03,0.31±0.03),and left middle temporal gyrus(0.28±0.03,0.26±0.02)(P<0.001).There were no significant differences of FA values in patients with aMCI.No correlations were found between the changes of FA values and changes of MMSE scores.Conclusion The decrease of FA values in AD patients showed more cerebral areas involved with the progress of the disease.FA values may serve as a sensitive tool to detect underlying white matter impairments with the progress of AD.