CTA Assessment Of Carotid Plaque Surface Ulceration And Histological Correlation

Background: The surface morphology of carotid atherosclerotic plaque is an independent marker of plaque rupture and an important predictor of ischemic stroke.Carotid CT angiography has obvious advantages in displaying plaque surface morphology due to its good spatial resolution.At present,there are only a few studies on the macroscopic characteristics of plaque,and the correlation of pathology is not clear.We conduct the study of carotid CT angiography to assess the correlation between plaque surface ulcers and plaque histopathology.Methods: Clinical data of patients undergoing carotid endarterectomy for carotid artery stenosis in the Department of Neurosurgery,Affiliated Hospital of Qingdao University from September 2016 to September 2020 were collected,and carotid plaque was divided into ulcer group and non-ulcer group according to the results of carotid artery CTA.Eight histopathological features of plaques were assessed microscopically using reproducible qualitative methods,clinical data and histopathological differences were compared between the two groups,and vulnerability indices were used to assess differences in plaque stability between the two groups.Results: By comparing the clinical data between the two groups,we found that the proportion of patients with previous history of cerebral infarction in the ulcer plaque group was significantly higher than that in the non-ulcer plaque group,and the difference was statistically significant(P<0.05).There were no significant differences in age,gender,history of hypertension,diabetes,TIA,coronary heart disease,smoking history,total cholesterol,triglyceride,low density lipoprotein and high density lipoprotein between 2groups(P>0.05).The histopathological features of ulcerated plaque identified by carotid artery CTA were significantly correlated with rupture of fibrous cap(P<0.01),hemorrhage within the plaque(P<0.01),and large necrotic core of lipid(P<0.05),but not with calcification,infiltration of inflammatory cells,neovascularization within the plaque,thrombosis on the plaque surface,and thin fibrous cap.At the same time,we calculated the vulnerability index of each group,and the mean vulnerability index of ulcer plaque group and non-ulcer plaque group were 2.01±0.51 and 0.49±0.25,respectively,the difference was statistically significant(t=22.7,P < 0.01).Conclusions: Our study is an exploration of the microscopic appearance of ulcerated plaques,identifying various histopathological features of ulcerated plaques identified by carotid artery CTA,and demonstrating a significant correlation with fibrous cap rupture,intraplaque hemorrhage,and large lipid necrotic core.At the same time,we also found that for non-ulcerative plaques identified by carotid artery CTA,ulcerative plaques tend to indicate greater instability and a significantly increased risk of ischemic stroke.