Abstract No. 538 An assessment of anterior cerebral artery anatomy impact for ACoA aneurysm initiation based on CFD analysis

Abstract

Aimed to identify anatomic, morphological and hemodynamic independent risk factors of the ACoA (anterior communicating artery) complex for ACoA aneurysm occurrence Records of patients and 3D angiography data of 15 consecutive patients harboring 15 ACoA aneurysms were retrospectively included. Computational fluid dynamics (CFD) simulations based on patient-specific models were carried out using 3D-TOF-MRA images. Reverse reconstruction technique was used for pre-aneurysm generation stimulation. Geometric parameters and hemodynamic changes were compared and evaluated. Fifteen ACoA aneurysms from 15 patients (10 females, 5 males, age 60.7 ±14 years) were used in this study. The overall prevalence of symmetric, dysplasia, and absent A1 was 53.3% (8/15), 26.7% (4/15), and 20% (3/15), respectively. Mean WSS of absence group (AG) was significantly higher compared with the symmetric (SG) and dysplasia group (DG). Absolute mean A1 artery flow (410.2±88 versus 439.4±101 mL/min; P=0.45) of the aneurysm side was similar between the SG and DG, but significantly higher in the AG (528.1±77 mL/min; P<0.05). The aneurysm-side A1-A2 angles showed no significant differences among the 3 groups, 103.4±9.2˚, 101.8±6.1˚ and 99.7±6.5˚ for the SG, DG, and AG (P=0.32). However, the mean A1-A2 angle on the aneurysm side were significantly lower than the contralateral A1-A2 angle (101.9±9.1˚ versus 120.3±7.7˚; P<0.05). Regression analysis demonstrated that higher WSS were significantly associated with larger A1-2 ratio (R2=0.52; P<0.05) The ACoA aneurysms are a high WSS and OSI pathology. Increased flow impingement and anatomic vasculature structure plays a triggering role in AcoA aneurysm occurrence.