Faster to the target – new microrobotic catheter to improve the treatment of strokes

Strokes are the second most common cause of death and of permanent disability worldwide. The faster the blood clot blocking blood flow to the brain can be removed, the greater the chances of patients not suffering any permanent damage. The biggest challenge in this minimally invasive procedure is the complex structure of the blood vessels. To optimize catheter navigation during endovascular procedures, the research group of Brad Nelson, Professor at the Multi-Scale Robotics Lab (MSRL) at ETH Zurich, is working on microrobotic catheters that are controlled by a magnetic field.

Magnetic, soft catheter tip

In the technology developed at the MSRL, the patient lies next to a navigation system that generates a directed magnetic field. The flexible microrobotic catheter has a diameter of less than one millimeter and a soft magnetic tip. The magnetic catheter tip can be steered in all directions using control software and is therefore easier to control than a manually guided wire. The system is being further developed for commercialization by the spin-off Nanoflex since 2021.

Helical structure on the surface

A recent publication by R. Dreyfus et al. in the journal Science Robotics now describes how a magnetically guided microrobot can be steered even more efficiently through blood vessels: A helical structure on the surface of the robot engages with the vessel wall and converts rotation into forward movement. This makes it much easier for the treating surgeon to push the catheter through fine and branched vessels. The research team worked together with engineers and neuroradiologists to demonstrate the feasibility of the approach. The microrobot was successfully navigated through the blood vessels of a living pig - from an artery past the heart to the millimeter-sized arteries of the brain.