Examination of brain area volumes based on voxel-based morphometry and multidomain cognitive impairment in asymptomatic unilateral carotid artery stenosis

Abstract

ObjectiveRecent evidence has demonstrated that unilateral carotid artery stenosis (CAS) can contribute to the development of cognitive impairment. However, the features of cognitive dysfunction induced by unilateral CAS remain unclear.MethodsSixty asymptomatic patients with unilateral CAS were divided into mild, moderate and severe stenosis groups. These patients and 20 healthy controls provided clinical data and serum, which was used to assess the levels of certain vascular risk factors. Then, they participated in a battery of neuropsychological tests. Additionally, all participants underwent a 3.0 T magnetic resonance imaging (MRI) scan of the brain. Chi-square tests and one-way ANOVA were used to determine significant differences in the risk factors and cognitive test scores between groups. Multiple logistic regression analysis and the receiver operating characteristic (ROC) curve analysis were performed to identify the independent risk factors for cognitive impairment in patients with CAS. Finally, fluid attenuated inversion recovery (FLAIR) T1-weighted MRI images were processed by voxel-based morphometry (VBM) analysis using the Statistical Parametric Mapping (SPM) 8 software.ResultsCompared with healthy controls, the scores of the Mini-Mental State Examination, Digital Span Test backward, and Rapid Verbal Retrieve were significantly reduced in patients with left CAS. The scores in all cognitive scales were significantly lower in patients with right CAS than in controls. Logistic regression analysis demonstrated that the degree of carotid stenosis was an independent risk factor for cognitive impairment in asymptomatic patients with unilateral CAS. Furthermore, VBM analysis showed that, compared with those in healthy controls, gray matter and white matter volumes in specific brain areas were markedly decreased in patients with severe unilateral CAS. However, in patients with moderate right CAS, there was a significant decline in the volume of gray matter in the left parahippocampal gyrus and supplementary motor area. Additionally, the volume of white matter in the left insula was obviously lower in patients with moderate right CAS than in healthy controls.ConclusionUnilateral asymptomatic CAS, especially on the right side, contributed to cognitive impairment, including memory, language, attention, executive function and visuospatial function. In addition, based on VBM analysis, both gray matter atrophy and white matter lesions were found in patients with unilateral asymptomatic CAS.

Alterations in brain morphology and functional connectivity mediate cognitive decline in carotid atherosclerotic stenosis

“…Cortical thinning and brain atrophy, as important imaging biomarkers in various brain diseases, were reported in previous studies (Hwang et al, 2015;Lambert et al, 2015;Nickel et al, 2019;Duan et al, 2023). We found left postcentral and superior parietal had significant CT decrement in CAS-MCI patients and the CT changes were associated with CASmax, MoCA scores, GMV changes, and seed-based FC changes.…”

“…To the best of our knowledge, no study has examined whether and how brain morphological and functional changes affect cognition in CAS patients with MCI at the same time. It is currently believed that hemodynamic abnormality is an important reason that may lead to brain morphological changes in CAS patients eventually causing cognitive impairment (Paraskevas et al, 2021;Duan et al, 2023). The correlation between high-grade CAS and cognitive impairment is related to silent embolization and hypoperfusion.…”

“…These findings suggest generalized white matter degeneration. Gray matter atrophy is also increasingly being reported in patients with CAS (Gao et al, 2021;Wang P. et al, 2021;Duan et al, 2023;Liu et al, 2024). Besides, functional connectivity or network abnormalities have also been found in patients with CAS (Ren et al, 2022;Fan et al, 2024).…”