A realistic way to investigate the design, and mechanical properties of flow diverter stents

Abstract

AbstractPurposeBraided flow diverters (FD) are highly sophisticated, delicate, and intricate mechanical devices used to treat intracranial aneurysms and thus saving lives. Testing such devices in vitro, however, remains an unsolved challenge. Here, we evaluate methods that access flow, design, and mechanical properties in vitro.MethodsFlow properties, cell porosity, and cell area were evaluated by placing FDs in patient-derived, 3D printed models of human vasculature. 4D flow MRI was used to measure fluid dynamics. Laser microscopy was used to measure porosity and cell area with the top of aneurysm sac cut off for the model. New testing methods were developed to investigate the bending, circumferential, and longitudinal radial force continuously over varying diameters.ResultsThe placement and flow properties of the FD in the vasculature models were successfully measured by MRI, although artifacts occurred. The setup to measure porosity and cell area inside of the model proved successful. The newly discussed methods allowed us to measure the indicated forces, to our knowledge for the first time, continuously.ConclusionModern and specifically tailored techniques, some of which were presented here for the first time, allow detailed insights into the flow and mechanical properties of braided flow diverter stents.