Abstract:

Objective To evaluate the relationship between pericarotid fat inflammation and acute cerebral infarction，and to measure perivascular fat density（PFD）by computed tomography angiography（CTA）to reflect the inflammation of adipose tissue. Methods In this study，patients with unilateral carotid artery atherosclerosis stenosis > 50%，and completing carotid artery CTA and brain diffusion⁃weighted imaging（DWI）were enrolled. According to DWI results，the patients were divided into acute infarction group（ACI group）and non⁃acute infarc⁃ tion group（NACI group）. The section of the carotid artery with the most severe lumen stenosis was selected from each patients；regions of interest（ROI）distribution were placed in the pericarotid adipose tissue on the side of the carotid artery stenosis and on the contralateral side of the axial plane，and the mean and maximum values of fat density were measured. The independent samples t ⁃test was used to evaluate the difference between the stenotic side and the contralateral PFD in the ACI group and the NACI group；the paired samples t⁃test to evaluate the difference between the stenotic side and the contralateral PFD in the two groups，and the mean and maximum values of PFD on the stenosis side of carotid artery were included in binary logistic regression analysis and ROC curve was drawn. Results The mean values（-57.87 ± 8.11 vs. -67.22 ± 8.18，P < 0.001）and maximum values （-46.53 ± 6.33 vs. -55.44 ± 7.24，P < 0.001）of PFD on stenotic side in the ACI group were higher than those inthe NACI group. There was no significant difference in the mean values（-78.82 ± 7.88 vs. -81.16 ± 7.94，P = 0.222） and maximum values（-71.32 ± 6.91 vs. -72.50 ± 6.61，P = 0.469）of PFD on contralateral side between the two groups. The paired t⁃test showed that mean values（-57.87 ± 8.11 vs. -78.82 ± 7.88，P < 0.001）and maximum values（-46.53 ± 6.33 vs. -71.32 ± 6.91，P < 0.001）of PFD on stenotic carotid artery side in the ACI group were higher than those on contralateral side，and mean values（-67.22 ± 8.18 vs. -81.16 ± 7.94，P < 0.001）and maxi⁃ mum values（-55.44 ± 7.24 vs. -72.50 ± 6.61，P < 0.001）of PFD on stenotic carotid artery side in the NACI group were also higher than those on contralateral side. Binary logistic regression analysis showed that mean values（OR = 1.185，95%CI 1.048 ~ 1.340）and maximum values（OR = 1.195，95%CI 1.054 ~ 1.353）of carotid artery PFD after adjusting for confounders were statistically significant（P < 0.05）. ROC curve analysis showed that mean values of carotid artery PFD［area under the curve（AUC）0.792，95%CI 0.678 ~ 0.879，P < 0.001］and the maximum values （AUC = 0.812，95%CI 0.701 ~ 0.896，P < 0.001）had high predictive value for cerebral infarction. Conclusions Fat density around the carotid artery on stenotic side of patients with ACI is higher than that on contralateral side， which indicates that the inflammatory reaction related to carotid atherosclerosis has extended to the perivascular adipose tissue. Carotid CTA technology can reflect the inflammatory of the adipose tissue around carotid artery and provide reference for the early prevention and treatment of cerebral infarction.

Key words:

carotid artery, perivascular fat density, cerebral infarction, computed tomography angi? ography