Characteristics of brain structural damage related to cerebral small vessel disease in general population with intracranial artery stenosis.

Background and aims: Covert MRI markers of cerebral small vessel disease (CSVD) can coexist with large artery atherosclerosis. We aimed to explore whether the spatial distributions of these markers were diverse in people with or without intracranial artery stenosis (ICAS).

Methods: This cross-sectional analysis included 1206 stroke-free participants (aged 55.69±9.27, 62.94% female) with brain MRI and MR angiography from community-based Shunyi cohort. We analysed the relationships between ICAS and CSVD markers. We also compared the probability maps of lacunes, cerebral microbleeds (CMB), white matter hyperintensities (WMH) and cortex morphology at a voxel/vertex-wise level in groups with and without ICAS.

Results: ICAS increased the risk of lacunes by 2.99-fold (95% CI 1.99 to 4.50, p<0.001), lacunes ≥3 by 5.32 times (95% CI 2.76 to 10.28, p<0.001), correlated with WMH volume (β=0.332, SE=0.059, p<0.001), WMH Fazekas scores ≥5 (OR 4.50, 95% CI 2.44 to 8.29, p<0.001) and brain parenchymal fraction (β=-0.012, SE=0.002, p<0.001), but not with CMB. ICAS is associated with lacunes in the corresponding blood supply area. Lacunes that coexist with ICAS were prone in basal ganglia, while the lacunes without ICAS appeared in centrum semiovale more often. WMH with ICAS was prone to present in deep white matter involving the bilateral pyramidal tracts and superior thalamic radiation. People with ICAS were susceptible to worse cortical atrophy of right superior frontal and left rostral anterior cingulate. No obvious distributional differences were found for CMB between the two groups.

Conclusions: Since ICAS may be involved in the upstream pathogenesis of lacunes, white matter lesions and cortical atrophy, the impact of ICAS should not be ignored when evaluating MRI markers of CSVD.