Multipole Magnetic Needle Positioning Method for Ultrasound-Guided Puncture

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Magnetic Navigation

Background:

• Ultrasound-guided puncture is crucial but faces challenges in real-time needle visualization.
• Existing external tracking systems lack portability and have large spatial footprints.
• Accurate needle positioning is essential for improving procedural success and safety.

Purpose of the Study:

• To develop a portable and accurate multipole magnetic needle positioning method for ultrasound-guided puncture.
• To integrate real-time needle position information into ultrasound systems.
• To enhance the ease of use for novices during puncture procedures.

Main Methods:

• A magnetic sensor array was integrated into the ultrasound probe.
• Needles were magnetized to generate a specific magnetic field for multipole magnetization.
• A positioning algorithm combined magnetic gradient tensor and direct inversion methods.
• Machine learning was employed for environmental magnetic field identification to improve accuracy.

Main Results:

• The environmental magnetic field identification achieved high accuracy (98.38%).
• Maximum positioning errors for needle tip and direction were 3.49 mm and 4.93 mm, respectively.
• Novices demonstrated a higher first-time success rate using the developed positioning system in phantom experiments.

Conclusions:

• The multipole magnetic needle positioning method accurately locates needles in real-time during ultrasound-guided puncture.
• The system enhances visualization, aiding novices in completing puncture tasks more effectively.
• This approach offers a new direction for ultrasound-guided navigation systems and can locate other ferromagnetic objects.