Objectives: The aim of the study was to investigate the difference of resting-state default-mode network (DMN) between patients with leukoaraiosis (LA)-associated subcortical vascular cognitive impairment (SVCI) and control subjects, and to provide functional imaging evidence of SVCI.
Methods: All subjects (n = 58) were divided into two groups based on their clinical diagnosis: a LA-associated SVCI group (n = 31, 14 males) and a control group (n = 27, 14 males). Demographic information and resting-state functional MRI (rs-fMRI) data were obtained. These subjects were assessed using the Hamilton Anxiety Depression Scale, Clinical Dementia Rating, Mini Mental State Exam, and Montreal Cognitive Assessment. Experimental data and confounding factors were described with a General Liner Model. Independent components of fMRI data were analyzed with an fMRI toolbox.
Results: The active areas involved in DMN of LA-associated SVCI group were similar to those of the control group. However, several active areas of LA-associated SVCI group, especially the left anterior cingulate cortex and the right parahippocampal gyrus, showed significantly lower blood oxygen level-dependent (BOLD) signals compared with the control group (p ≤ 0.05); whereas the left caudate nucleus (p = 0.015), the right frontal lobe (p = 0.004), and the superior temporal gyrus/inferior parietal gyrus (p = 0.001) exhibited significantly higher BOLD signals compared with the control group.
Discussion: The present study provides neuroimaging evidence for the recognition of LA-associated SVCI. Moreover, the differences in the functional alterations of the resting-state DMN might be a distinguishing feature between SVCI and amnestic mild cognitive impairment patients.
Keywords: Default-mode network; Dementia; Leukoaraiosis; Subcortical vascular cognitive impairment.