Correlation between prefrontal-striatal pathway impairment and cognitive impairment in patients with leukoaraiosis

Abstract

Our study aimed to investigate the changes of white matter microstructure of cortico-subcortical pathways using diffusion tensor imaging (DTI), and to explore the relationship between abnormal parameters of DTI and cognitive function underlying in patients with leukoaraiosis (LA).A total of 42 patients with LA and 42 age- and sex-matched healthy controls were recruited from Beijing Chaoyang Hospital, Capital Medical University between January 2012 and December 2012. All the subjects underwent scans of conventional magnetic resonance imaging and DTI, and a comprehensive neuropsychological battery was utilized. The regions of interest (ROIs) were located at the white matter of centrum semiovale, anterior and posterior periventricular white matter, basal ganglia, corpus callosum. The averaged values of mean diffusivity (MD) and fractional anisotropy (FA) were quantified both within white matter lesions (WMLs) and normal appearing white matter (NAWM). A linear regression analysis was performed to assess the association between diffusion parameters and decline in cognitive domains.Patients with LA were associated with comprehensive cognitive function deficits. We found that significantly decreased FA and increased MD in WMLs at the 5 ROIs than that of NAWM and controls (P < .05). The values of FA in NAWM were significantly lower and MD in NAWM were significantly higher at centrum semiovale and posterior periventricular white matter than that of controls (P < .05). The values of FA in WMLs at anterior periventricular white matter were positively related to the performances of cognition in patients with LA (P < .05). The values of FA in NAWM located at anterior periventricular white matter were positively related to the score of Digit-symbol test (r = 0.446, P = .002). The values of FA in NAWM located at anterior periventricular white matter correlated inversely with the Z scores of executive function (r = −0.418, P = .03).In our study, patients with LA exhibited significant cognitive impairment especially in the domains of executive function. The technique of DTI revealed that the reduced FA and increased MD at the corresponding regions of cortico-subcortical pathways in patients with LA. DTI may be of great help for an early pathology of white matter microstructure underlying in patients with LA.

Microstructural disruption of the right inferior fronto‐occipital and inferior longitudinal fasciculus contributes to WMH‐related cognitive impairment

“…White matter hyperintensities is the most common neuroimaging manifestation of CSVD, which is related to cognitive dysfunction or dementia. Studies that focused on NAWM have also confirmed that the change in DTI metrics of NAWM always precedes the development of WMH and is associated with MCI . Combined with the emergence of WMH penumbra theory, we propose that direct visual WMH may be a manifestation of more extensive and subtle WM microstructural degeneration and those changes of the properties in DTI may be the potential mechanism of WMH‐related MCI, as stated in the theory of cortical “disconnection” hypothesis .…”

“…Longitudinal follow‐up studies also showed further deterioration of cognitive function over time in WMH patients with mild cognitive impairment . Furthermore, loss of microstructural integrity of normal‐appearing white matter (NAWM) was associated with executive function, which further suggested that WMH might be an extreme case of continuous spectrum of white matter (WM) damage. White matter tract disruption in diffusion tensor imaging (DTI) may lead to disconnections among cortico‐cortical or cortico‐subcortical pathways vital for some cognitive function.…”

Functional Disorganization of Small-World Brain Networks in Patients With Ischemic Leukoaraiosis

“…Indeed, our findings are supported by many previous neuroimaging studies. For example, microstructural WM disruption has been documented in ILA, such as the frontal WM tracts and corpus callosum (Yamauchi et al, 2000 ; Jokinen et al, 2007 ; Viana-Baptista et al, 2008 ; Wang et al, 2017 ). Moreover, resting-state functional MRI studies have also shown ILA-related alterations in functional connectivity (Chen et al, 2019 ; Liu et al, 2019a , b ).…”

Review of diffusion MRI studies in chronic white matter diseases

“…We separately grouped the studies based on cross-sectional or longitudinal analysis. Studies on LA were entirely crosssectional [47,57,62] whereas studies related to VCI were predominantly longitudinal. Longitudinal studies [63,67,70,[78][79][80][81][83][84][85][86] focused on characterizing the disease progression using DTI measures.…”