Surface-based morphometry of the cerebral cortex in cognitive impairments of varying severity in patients with age-related cerebral small vessel disease

BACKGROUND: Analysis of structural magnetic resonance images is essential to assessing the main substrate of cognitive impairment in sporadic age-related cerebral small vessel disease, accounting for up to 45% of all dementia cases. Variations in the results of magnetic resonance morphometry applied in cerebral small vessel disease require extensive studies and clinical correlation. AIM: To assess cerebral atrophy features in cognitive impairment in patients with cerebral small vessel disease by surface-based morphometry. MATERIALS AND METHODS: A prospective study was conducted to assess patients with cerebral small vessel disease and cognitive impairments of varying severity levels (subjective, moderate, and dementia) and sex- and age-matched groups of volunteers. The assessment included the analysis of signs of cerebral small vessel disease based on the results of magnetic resonance imaging with the computation of general cerebral small vessel disease index and processing T1 multiplanar reconstruction images by surface-based morphometry to quantify general and regional brain parameters, including the thickness of the cerebral cortex. RESULTS: The main group consisted of 173 patients with cerebral small vessel disease, whereas the control group included 47 healthy volunteers. As the severity of brain structural changes and cognitive impairments increased, a significant (p 0.05) decrease in the cortical thickness of certain regions following a similar pattern was reported, particularly in the cingulate gyri, mainly their posterior sections; medial and middle sections of the frontal lobes, various areas of the insular cortex, and temporoparietal areas, particularly the supramarginal gyri. The brain volumes (overall, gray matter, and white matter volumes) in cerebral small vessel disease were significantly different only in controls but not between patients with cognitive impairment of different severity levels. The hyperintense white matter volume was significantly different between patients with dementia and moderate cognitive impairment, dementia, and subjective cognitive impairment (p 0.0001). CONCLUSIONS: The results confirm secondary/mixed atrophy in cerebral small vessel disease. The clarification of the severity level of cognitive impairment in cerebral small vessel disease based on atrophy data is limited by the wide variety of regions with significant cortical thinning. Thus, the quantification of the cortex can only be a supplementary method in predicting cerebral small vessel disease progression.