Feasibility Study of Investigating Soft Embolic Particle Transport Using an In Vitro Benchtop Flow Loop Model

Stroke continues to be a critical health issue of global concern. A significant mechanism of stroke is embolic. wherein a fragmented piece of blood clot (embolus) migrates from its source to occlude cerebral arteries. Hence, embolic stroke occurrence is highly dependent on embolic pathways in the bloodstream. Prior investigations have shown that embolus distribution does not necessarily follow flow distribution. However, most existing models assume emboli to be quasi-rigid, and limited insights are available on how embolus deformability influences distribution. Replicating physiologic soft embolus transport in pulsatile flow through anatomical vascular pathways is a challenging task. Here, we demonstrate the feasibility of a benchtop model of soft-particle transport in a flow-loop comprising 3D printed human anatomical vessel models. The particles are prepared in the form of calcium alginate beads fabricated using a drip-infusion setup. Particle sizing is characterized as a function of fabrication parameters. The particles are then introduced into the flow loop and their dynamics and distribution across pulsatile flow in a carotid bifurcation model is quantified using high-speed videography and particle counting. Comparing these variables against those obtained from experiments with rigid particles of same size and density, we discuss how deformability may influence embolus distribution across vascular bifurcations.