X-Ray-Guided Robotic Platform for Remote Control of Untethered Magnetic Robots Targeting Blood Clots in the Iliac Artery

To date, the deployment of untethered magnetic robots (UMRs), activated by rotating permanent magnets, has been limited to controlled settings that do not replicate the dynamic conditions encountered in vivo. This study addresses this gap by exploring the challenges associated with transitioning UMRs from artificial environments to more realistic ex vivo scenarios, aiming to enhance their adaptability and functionality in dynamic physiological conditions. Initially, we develop an ex vivo endovascular thrombosis model in the iliac artery, facilitating the evaluation of clot removal through mechanical or chemical means. Subsequently, we deploy millimeter-sized bio-compatible UMRs and maneuver them toward blood clots using an X-ray-guided robotic platform. This demonstration showcases the operator's adept control in directing the UMRs precisely toward the blood clot, effectively engaging with it to reinstate blood flow. Utilizing cone-beam computed tomography scans for volume reconstruction of the clot (initial volume of 21.8 mm³) at specific time points, we illustrate that a significant volume reduction of 16 % can be accomplished in under 30 minutes, all without the use of thrombolytic agents.