Design and Actuation of a Multipole Ring Magnet for Navigating Endovascular Magnetic Instruments
Julian Raub, Lucio Pancaldi, Loïc Jonathan Von Deschwanden, Mahmut Selman Sakar
AI summary
Problem
Navigating distal brain vessels endovascularly remains challenging due to complex anatomy, while existing magnetic navigation systems often compromise imaging fidelity or lack sufficient field uniformity for precise steering.
Approach
The authors designed an optimized eight-magnet ring configuration that generates a strong, uniform horizontal magnetic field and integrated it into a compact platform with a central aperture and side windows to maintain continuous X-ray visibility during actuation.
Key results
- Optimized eight-magnet ring geometry for maximal field strength and imaging clearance
- Validated magnetic field model with <2% magnitude error and 2° angular deviation
- Demonstrated precise in-plane steering of flow-driven microcatheters in planar phantoms
- Achieved reliable out-of-plane 3D navigation through curved bifurcating vessel phantoms
Why it matters
This imaging-compatible actuation platform advances the clinical translation of robotic endovascular interventions by enabling precise catheter steering under continuous fluoroscopy.
Abstract
This paper presents the design and analysis of a compact magnetic field generator for robotic navigation of mag- netic endovascular instruments in clinical settings. The system features eight symmetrically arranged permanent magnets in a ring configuration, maximizing magnetic field uniformity and aperture size for X-ray transmission while minimizing spatial footprint and magnet motion for uninterrupted fluoroscopy imag- ing. The rationale behind the design of the system is explained through analytical considerations of magnetic field distribution. In vitro demonstrations inside perfused biomimetic phantoms confirm the system’s capability for 3D steering of flow-driven magnetic microcatheters, opening a path for pre-clinical testing.