Hemodynamic Impact of Morphological Changes in Intracranial Aneurysms Treated with the Contour Neurovascular System: A Pilot In Silico Study.

Background: The Contour Neurovascular System (CNS) has been established as an effective treatment for wide-neck intracranial bifurcation aneurysms. However, its post-intervention hemodynamic impact remains insufficiently understood. In silico studies investigating the associated hemodynamic changes are limited and rarely consider post-interventional configurations. Methods: Five intracranial aneurysms treated with the CNS were retrospectively analyzed using both pre-interventional and 24 h post-interventional imaging data. CNS-associated morphological changes were assessed, and virtual CNS deployment was performed in pre- and post-interventional configurations. Consequently, 20 high-fidelity, image-based blood flow simulations were performed to evaluate six flow- and shear-related parameters. Results: All cases exhibited an increase in ostium area between pre- and post-interventional configurations (118.7% ± 52.4%), whereas no relevant geometric differences were observed in the surrounding vessels. Hemodynamic analyses revealed that morphological differences were associated with variations in flow characteristics. In particular, most post-interventional configurations showed higher intra-aneurysmal velocities independent of device implantation, although CNS deployment consistently reduced all investigated parameters (reduction in intra-aneurysmal velocity-pre-interventional with CNS: -83.5% ± 14.0%; post-interventional with CNS: -72.4% ± 19.4%). Conclusions: In this exploratory study, the observed CNS-associated morphological differences were accompanied by variations in aneurysmal hemodynamics, potentially influencing the estimated treatment effect. Although validation in larger cohorts is required, these findings highlight the potential value of 3D-DSA follow-up imaging for a more comprehensive assessment of CNS-associated changes and outcomes.