Multivariate predictors of anterior communicating artery aneurysm formation by regression analysis using three-dimensional digital subtraction angiography and transcranial color-coded duplex with emphasis on Willis circle variation and hemodynamic forces alteration

Abstract

Objective To evaluate the predictors of anterior communicating artery (AcoA) intracranial aneurysm formation by regression analysis using three-dimensional digital subtraction angiography (3D-DSA) and transcranial color-coded duplex (TCCD) with emphasis on Willis circle variation and hemodynamic forces alteration, and provide references for high-risk population screening for intracranial aneurysm and prevention in the future. Methods Eighty-one patients with AcoA aneurysm, admitted to our hospital from November 2010 to November 2011 and confirmed by DSA, were selected as aneurysm group; 3D-DSA images were carefully evaluated to confirm the vascular structural abnormality, including the presence of A1 dominance and Willis circle variation; additionally, TCCD was performed to record the hemodynamic parameters which were used to calculate shearing stress and mechanical stretch. One hundred and eighteen patients who have a negative result checked by DSA were chosen as controls at the same period. Differences of hemodynamic parameters and vascular architecture between the two groups were compared. The risk factors of AcoA aneurysm formation were analyzed by using receiver operating characteristic (ROC) curve and multivariate Logistic regression with emphasis on Willis circle variation and hemodynamic forces alteration. Results There were significant differences in the aspects of A1 dominance, angle between A2 segments of bilateral anterior cerebral artery (ACA) and shearing stress between AcoA aneurysm group and control group (P<0.05). Additionally, the ROC curve showed that the angle between A2 segments of bilateral ACA and shearing stress and significantly characterize the formation of AcoA aneurysms (P<0.05). Gender, hypertension (grade II), Willis circle variation (OR=14.152, 95%CI: 1.006-199.012, P=0.049), A1 dominance (OR=25.048, 95%CI: 1.438-436.337, P=0.027) are risk factors of AcoA aneurysm formation. Diabetes (FBG at the normal level), shearing stress (OR=0.053, 95%CI: 0.011-0.249, P=0.000), angle between A2 segments of bilateral ACA (OR=0.037, 95% CI: 0.007-0.211, P=0.000) are identified as protective factors. Conclusions Willis circle variation, A1 dominance, shearing stress, angle between A2 segments of bilateral ACA are influencing factors of AcoA aneurysm formation. There is great clinical significance to accurately assess the influencing factors of AcoA aneurysm in guiding clinical prevention and treatment decision making. Key words: Intracranial aneurysm; Anterior communicating artery, Willis circle variation; Hemodynamic forces alteration; Influencing factor