Impact of body movement on the hemodynamics of cerebral aneurysm, an ex-vivo experimental study

Research on exercise hemodynamics has studied how body movement caused an increased frequency of pulsatile changes in pressure and flows, vessel stiffness, and blood flow shear stress. However, body movement can affect hemodynamics due to the physical motion of the vessel wall shaking the blood. This is a largely ignored yet crucial phenomenon that needs to be quantitatively investigated. In the study, we aim to study how human body movement may impact the hemodynamics of cerebral aneurysms, beyond typical physiological responses. We first employ a motion collection system to capture the human head movement. We then implement a six-degree-of-freedom motion simulation platform to replay the human head motion. Lastly, and most importantly, we perform an ex-vivo hemodynamics measurement in a cerebral aneurysm phantom model, using a high-speed PIV system on this motion simulation platform. Both simplified and patient-specific cerebral aneurysm models are utilized, and different inlet blood flow conditions are tested during this study. In the control group, we measure hemodynamics when the motion simulation platform is at rest. In the treatment group, the hemodynamics measurement and body movement replaying are simultaneously conducted, with identical inlet flow conditions. We evidenced clear differences in hemodynamics in these two groups. This study suggests that, besides physiological response, body movement also physically contributes to the intense hemodynamics changes that need to be considered during any drug or biomedical device design and verification.