A QUANTITATIVE SUSCEPTIBILITY MAPPING STUDY IN ALZHEIMER'S DISEASE

Abstract

In the pathological study of Alzheimer's disease, overloaded iron is presented in senile plaques and neurofibrillary tangles. The role of brain iron accumulation in AD is uncertain. We aimed to study the changes of iron accumulation using quantitative susceptibility mapping (QSM) in patients with AD and Mild cognitive impairment (MCI). Ten patients with AD, 10 patients with MCI and 20 normal controls (NC) were recruited. All subjects were examined by magnetic resonance imaging (MRI) to analyze the difference of iron accumulation among groups with QSM sequence. The differences of the susceptibility data among the three groups were investigated by region of interest (ROI)-based comparisons using a one-way analysis of variance (ANOVA) test, pairwise multiple comparison was made with the least significant difference (LSD) method. ROIs were set on bilateral caudate nucleus, putamen, hippocampus and amygdala. First and foremost, average susceptibility of the bilateral caudate nucleus and left putamen were significant differences among groups (p<0.001, respectively). Maximal susceptibility of the left caudate nucleus was significant difference among groups (p<0.001). There are no significant difference in average susceptibility of right putamen and maximal susceptibility of the right caudate nucleus among groups (p=0.888 and p=0.331, respectively). There are no homogeneity of variance in the maximal susceptibility of bilateral putamen. Besides, there are poor reproducibility in hippocampus and amygdala of each subjects because the standard deviation is obviously higher than the average value, which indicate iron are very unevenly distributed in those areas. Furthermore, there is no significant correlation between susceptibility and age in elderly NC groups.