P082 Hemodynamic analysis of PCOM aneurysms – Flow change depending on anatomical variation

<h3>Introduction</h3> The flow characteristics of bifurcation aneurysms of the posterior communicating artery (PCOM) have rarely been studied. Especially in the presence of a fetal posterior circulation (FPC), the likelihood of complete PCOM aneurysm occlusion after endovascular treatment is reduced. Due to this, PCOM aneurysms in anatomical variations of the posterior circulation represent a major challenge.[1] <h3>Aim of Study</h3> Investigating variations in fetal and non-fetal configurations and its hemodynamic impact on PCOM aneurysms. <h3>Methods</h3> 3D-DSA data of 18 patients harboring bifurcation aneurysms at the PCOM are collected. 11 patients demonstrate a FPC and 7 patients a non-FPC. Patient-specific 3D models containing at least one bifurcation distal the aneurysm in the anterior circulation as well as the PCOM itself are extracted. Using image-based blood flow simulations, hemodynamics of all aneurysm models are calculated. The outflow of the PCOM is artificially varied representing fetal and non-fetal conditions for every model. <h3>Results</h3> PCOM aneurysms generally exhibit a lower wall shear stress on the aneurysm wall compared to the surrounding parent vessels. Due to the increase of the PCOM outflow, indicating a fetal state, higher local wall shear stresses are detected at the distal aneurysm side. Furthermore, fetal configurations show higher velocities in the PCOM itself as well as a slightly higher flow distribution in the aneurysm sac. <h3>Conclusion</h3> The presence of posterior anatomical variations affects the hemodynamic parameters of PCOM bifurcation aneurysms. In particular, the presence of an FPC has an unfavourable effect on the intraaneurysmal flow dynamics. <h3>Disclosure of Interest</h3> no.