Diffusion tensor imaging study of the temporal stem in Alzheimer's disease

Abstract

Objective To study the changes of fractional anisotropy (FA) value of white matter of brain and temporal stem in Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI) patients as well as normal cognitive (NC) aged people with diffusion tensor imaging (DTI), and explore the damage mechanism of temporal stem and its diagnostic value on AD and aMCI. Methods Ten patients with AD, 10 patients with aMCI and 10 NC volunteers as control group were scanned by routine MRI and DTI. FA values were calculated by post-processing software (DTIstudio) in temporal stem (including anterior commissure, uncinate fasciculus and inferior occipitofrontal fasciculus), and white matter in anterior frontal, temperal, parietal and occipital lobes. The data were analyzed by SPSS 13.0. If bilateral differences of FA values were not statistically significant (P > 0.05), the average values of bilateral FA were selected and compared among 3 groups. If bilateral differences of FA values were statistically significant (P < 0.05), the measurement values were directly compared. Results 1) There was no significantdifference of FA values in bilateral symmetric white matter and temporal stem among AD, aMCI and NC groups (P > 0.05, for all). 2) There was significant difference of FA values in anterior commissure, uncinate fasciculus and inferior occipitofrontal fasciculus between AD and aMCI groups (P < 0.05, for all). 3) There was significant difference of FA values in anterior commissure, uncinate fasciculus, inferior occipitofrontal fasciculus, anterior frontal and parietal lobes between AD and NC groups (P < 0.05, for all). 4) There was no significant difference of FA values in anterior commissure, uncinate fasciculus, inferior occipitofrontal fasciculus, anterior frontal lobe between aMCI and NC groups (P > 0.05, for all). Conclusions The significant difference of FA values in temporal stem among AD, aMCI and NC groups suggests that temporal stem fiber bundles are of great significance in the white matter damage of AD, and DTI is helpful for the differential diagnosis of AD, aMCI and NC. The abnormal changes of FA values in anterior commissure, uncinate fasciculus, inferior occipitofrontal fasciculus, anterior frontal and parietal lobes are of great diagnostic value in AD.

doi: 10.3969/j.issn.1672-6731.2014.03.011