Objective:To analyze the correlation between cognitive impairment and cortical atrophy in elderly patients with asymptomatic carotid artery stenosis (ACAS).Methods:In this cross-sectional study, 40 consecutive elderly patients with ACAS treated in the Department of Neurology, Northern Jiangsu People′s Hospital from July 1, 2020 to June 30, 2021 (ACAS group), and 40 elderly healthy controls who accepted physical examination during the same period (control group) were included. Cognitive assessment was performed using the Mental State Examination Scale (MMSE) and the Montreal Cognitive Assessment Scale (MoCA), and brain magnetic resonance imaging scanning was performed in the ACAS group. The artificial intelligence technique was applied for brain lobe segmentation and cortical volume calculation. The χ2-test, independent sample t-test and Wilcoxon non-parametric test were used to analyze the difference of clinical data and cognitive scores between the two groups. In the ACAS group, the cortical volumes of the side with carotid stenosis was compared with that of the normal side, and Spearman′s correlation analysis was used to assess the correlation between cognitive scores and cortical atrophy. Results:Compared with the control group, the ACAS group got significantly lower scores of MMSE and MoCA, as well as lower scores of visuospatial executive function, attention and calculation, language function, abstraction ability and delayed recall [(25.60±2.49) vs (27.18±1.01), (22.05±3.59) vs (25.60±1.43), (2.73±1.04) vs (4.08±0.62), (4.53±0.93) vs (5.03±0.66), 2.00 (0.00) vs 3.00 (0.00), 1.00 (1.00) vs 2.00 (0.00), and (2.95±0.96) vs (3.35±0.62)] (all P<0.05). There was not significant differences in naming and orientation ability between the two groups (both P>0.05). The volume of cortical, temporal lobe, frontal lobe, parietal lobe and insular lobe on the side with carotid stenosis in the ACAS group were significantly smaller than those on the normal side [186.23 (177.97, 202.53) vs 194.67 (185.65, 204.82) cm 3, 54.74 (50.66, 56.95) vs 55.61 (51.24, 58.49) cm 3, 72.98 (70.76, 78.34) vs 75.27 (72.34, 80.66) cm 3, 53.66 (51.11, 57.86) vs 56.59 (52.80, 60.09) cm 3, 6.57 (6.35, 7.07) vs 6.72 (6.46, 7.34) cm 3] (all P<0.05). The MoCA score in the ACAS group was positively related to the cortical volume ratio of the two sides ( r=0.427, P<0.01). The attention ( r=0.353) and abstraction ( r=0.226) ability scores were positively correlated with the temporal lobe volume ratios of the two sides (both P<0.05). The visuospatial executive ( r=0.187) and language ( r=0.373) ability scores were positively correlated with frontal lobe volume ratios of the two sides (both P<0.05), and visuospatial executive ( r=0.386), naming ( r=0.344), language ( r=0.517), abstraction ( r=0.335) and delayed recall ( r=0.333) ability scores were positively correlated with parietal lobe volume ratios of the two sides (all P<0.05). Conclusion:In elderly patients with ACAS, the cognitive impairment and cortical atrophy on the sides with carotid stenosis are significant and a positive correlation is detected between them.