3D Targeting of a Magnetic Particle in Blood Vessels Using Field-Free Points in an Open-Type Electromagnetic Actuation System
Seungun Yang, Kim Tien Nguyen, Hyeonwoo Kee, Hyoryong Lee, Jayoung Kim, Sukho Park
AI summary
Problem
Closed-type electromagnetic actuation systems are difficult to integrate into surgical environments and imaging setups, while existing open-type systems suffer from rapid magnetic force decay and field anisotropy at distance.
Approach
The researchers optimized a six-coil open-type system using composite electro-permanent magnetic actuators and developed a new field-free point generation method that maximizes isotropic magnetic gradients along the desired steering axis.
Key results
- CEPMA coils increased magnetic field strength by 50.2% and gradient by 43.0% over traditional designs
- Optimized six-coil layout achieved highly isotropic field-free points across the surgical region of interest
- Novel field-free point algorithm produced up to 3.3× stronger magnetic gradients with improved force alignment
- Successfully validated 3D particle steering through simulated Y-shaped and liver vasculature phantoms
Why it matters
Provides a practical, imaging-compatible magnetic navigation platform for precise targeted drug delivery in minimally invasive surgeries.
Abstract
Recent research has increasingly focused on delivering drug-carrying magnetic particles to diseased areas using electromagnetic actuation (EMA) systems. Particularly, in these systems, creating a field-free point (FFP) and using it to steer magnetic particles in the desired direction has attracted significant attention. However, most previous studies use closed- type EMA systems, which, due to their structural characteristics, are difficult to integrate into actual surgical environments and to operate in conjunction with external imaging systems like X-ray. This study addresses these limitations by using an open-type EMA system, which is better suited for surgical integration. However, an open-type EMA system faces issues such as a significant decrease in magnetic force and an anisotropic magnetic field as the distance from the coils increases in the region of interest (ROI). To overcome these challenges, we optimized the open-type EMA system and proposed a suitable FFP generation method. Furthermore, we presented a targeting algorithm for steering a magnetic particle in blood vessels using anisotropic FFP. This proposed open-type EMA system and the control strategy using FFP were validated through multiphysics simulations and phantom experiments, proving the viability of magnetic particle targeting.