Tortuosity of the internal carotid artery and the formation of internal carotid aneurysms: an exploratory study based on propensity score method / 中华放射学杂志

ABSTRACT

Objective:To investigate the correlation between the tortuosity of the internal carotid artery and the formation of internal carotid aneurysms.Methods:The clinical data of patients with suspected cerebrovascular disease admitted to the Jinling Hospital from July 2009 to March 2017 were retrospectively collected. All patients underwent head CT angiography and digital subtraction angiography. Patients with single internal carotid artery aneurysm were classified as the aneurysm group, and patients without obvious abnormal vascular disease were classified as the control group. The demographic information of the patients, including age, gender, history of hypertension and diabetes, were collected. The size of the aneurysm and the tortuosity parameters of the internal carotid artery were measured, including the classification of the tortuosity of internal carotid artery, anterior genu angle (A angle), posterior genu angle (P angle), sum of the angles of A angle and P angle (AP angle) and height difference of anterior genu and posterior genu (D value). SPSS software was used for propensity score matching (PSM). Independent sample t test, Mann-Whitney U test or χ 2 test, Fisher exact test were used to compare the differences of each parameter between the two groups. Spearman analysis was used to analyze the correlation between the tortuosity and aneurysm size. A multivariate logistic regression was used to analyze the independent risk factors of aneurysm formation and to predict the formation of internal carotid aneurysm. The receiver operating characteristic curve and the area under the curve were used for model performance. Results:After PSM, 108 patients were included in each group. The proportion of tortuous internal carotid artery in the aneurysm group was lower than that in the control group [19.4% (21/108) vs. 32.4% (35/108), χ 2=4.72, P=0.030]. A, P and AP angles in the aneurysm group were significantly larger than those in the control group ( U=7 105.50, P=0.006; U=7 139.00, P=0.004; t=-3.14, P=0.002). Multivariate logistic regression analysis showed that AP angle (OR=1.010, 95%CI 1.003-1.016, P=0.002) was an independent risk factor for aneurysm formation. The area under the curves of logistic regression model based on AP angle was 0.624 (95%CI 0.549-0.699). There was a weak correlation between the size of internal carotid artery aneurysm and AP angle ( r=0.210, P=0.002). Conclusions:The tortuosity of the internal carotid artery is associated with the formation of internal carotid artery aneurysms, and the AP angle is an independent risk factor for the formation of internal carotid artery aneurysms, and a weak positive correlation with the size of the aneurysm is observed. It provides a new idea for understanding the formation of internal carotid artery aneurysms from the morphological characteristics of the parent artery.