Magnetic catheter manipulation in the interventional MR imaging environment

Area of Science:

• Medical Devices
• Interventional Radiology
• Magnetic Resonance Imaging

Background:

• Endovascular procedures require precise catheter navigation.
• Magnetic resonance (MR) imaging offers excellent soft-tissue visualization but poses challenges for device steering.
• Developing steerable catheters compatible with MR environments is crucial for advancing minimally invasive treatments.

Purpose of the Study:

• To assess the deflection capabilities of a prototype endovascular catheter.
• The catheter is remotely magnetically steerable and designed for interventional MR imaging.
• Evaluation focused on controlled manipulation in an MR-compatible setting.

Main Methods:

• Copper coils were fabricated using plasma vapor deposition and laser lithography on microcatheter tips.
• Both helical and saddle-shaped coils were integrated onto a single catheter.
• Deflection was tested in water phantoms within a 1.5-T MR scanner, with variable currents applied to the coils.
• Real-time MR imaging tracked catheter tip deflection and orientation.

Main Results:

• Catheter tips were clearly visualized using MR imaging.
• Energizing the coils produced visible magnetic field artifacts.
• Applied current consistently controlled catheter deflection, with polarity reversal altering the direction.
• Activating multiple coils resulted in composite deflection vectors.
• Successful navigation through a vascular phantom was achieved.

Conclusions:

• Laser-lithographed, multiaxis coil-tipped catheters enable controlled deflection.
• This technology is viable for use within the MR imaging environment.
• The findings support the development of MR-compatible steerable catheters.