扩散张量成像观察遗忘型轻度认知障碍患者联合纤维束

Diffusion tensor imaging of association fiber tracts in amnestic mild cognitive impairment

目的通过磁共振扩散张量成像(DTI)探讨遗忘型轻度认知障碍(aMCI)患者联合纤维束FA值和ADC值的变化特点,评价DTI对aMCI的诊断及aMCI与AD鉴别诊断的应用价值。方法对20例aMCI患者(aMCI组)、20例AD患者(AD组)及20名正常对照者(对照组)行DTI扫描,以额枕下束、胼胝体膝部及压部、上纵束Ⅱ、扣带束作为感兴趣区(ROI)测FA值和ADC值。结果aMCI组与NC组比较额枕下束和扣带束FA值差异有统计学意义(P<0.05);aMCI组与AD组比较扣带束FA值差异有统计学意义(P<0.05)。结论aMCI患者额枕下束、扣带束FA值的异常改变,提示DTI检查可作为aMCI的一个诊断指标。aMCI患者与AD患者扣带束FA值有差异,有助于aMCI与AD的鉴别诊断。

Objective To investigate the characteristics of fractional anisotropy（FA）and apparent diffusion coefficient（ADC）of association fiber tracts in patients with amnestic mild cognitive impairment（aMCI）,and to assess the application value of diffusion tensor imaging（DTI）in differential diagnosis of aMCI and AD.Methods DTI were performed in 20 patients of aMCI（aMCI group）,20 patients of AD（AD group）and 20 normal control subjects（control group）.FA and ADC values were calculated in the regions of interest（ROI）in inferior fronto-occipital fasciculus（IFOF）,genu and splenium of corpus callosum,superior longitudinal fasciclesⅡ（SLFⅡ）and cingulated bundles.Results There was significant difference of FA values in inferior fronto-occipital fasciculus and cingulate bundles between aMCI group compared with control group（P 〈0.05）,as well as of FA values in cingulate bundles between aMCI group and AD group（P〈 0.05）.Conclusion Abnormal FA values in inferior fronto-occipital fasciculus and cingulate bundles suggest that DTI can be used as a diagnosis index of aMCI.Furthermore,it is helpful in the differential diagnosis of aMCI and AD.