A numerical framework to investigate hemodynamics during endovascular mechanical recanalization in acute stroke

• Published in: International journal for numerical methods in biomedical engineering 2016-04, Vol.32 (4), p.e02748-n/a
• Main Authors: Neidlin, Michael, Büsen, Martin, Brockmann, Carolin, Wiesmann, Martin, Sonntag, Simon J., Steinseifer, Ulrich, Kaufmann, Tim A S
• Format: Article
• Language: English
• Subjects: aspiration; cerebral hemodynamics; Endovascular Procedures; Hemodynamics; Humans; Models, Cardiovascular; multiscale simulation; Numerical Analysis, Computer-Assisted; Regional Blood Flow; Reproducibility of Results; Stroke - physiopathology; Stroke - surgery; stroke intervention; Suction; thrombectomy; Thrombosis - pathology; Vascular Resistance
• ISSN: 2040-7939; 2040-7947
• DOI: 10.1002/cnm.2748

Summary Ischemic stroke, caused by embolism of cerebral vessels, inflicts high morbidity and mortality. Endovascular aspiration of the blood clot is an interventional technique for the recanalization of the occluded arteries. However, the hemodynamics in the Circle of Willis (CoW) are not completely understood, which results in medical misjudgment and complications during surgeries. In this study we establish a multiscale description of cerebral hemodynamics during aspiration thrombectomy. First, the CoW is modeled as a 1D pipe network on the basis of computed tomography angiography (CTA) scans. Afterwards, a vascular occlusion is placed in the middle cerebral artery and the relevant section of the CoW is transferred to a 3D computational fluid dynamic (CFD) domain. A suction catheter in different positions is included in the CFD simulations. The boundary conditions of the 3D domain are taken from the 1D domain to ensure system coupling. A Eulerian–Eulerian multiphase simulation describes the process of thrombus aspiration. The physiological blood flow in the 1D and 3D domains is validated with literature data. Further on, it is proved that domain reduction and pressure coupling at the boundaries are an appropriate method to reduce computational costs. Future work will apply the developed framework to various clinical questions. Copyright © 2015 John Wiley & Sons, Ltd. The work presents a multiscale description to investigate the global and local hemodynamics in the CoW during acute stroke interventions. 1D and 3D models are derived from CTA scans, and the blood flow is computed for an occluded and non‐occluded configuration. The framework shows accordance with in vivo measurements of blood flow as well as a feasible modeling tool to compare cannula tip positioning during clot aspiration.