Gradient coil design with enhanced shielding constraint for a cryogen-free superconducting MRI system

Area of Science:

• Medical Imaging
• Applied Physics
• Magnetics Engineering

Background:

• Cryogen-free superconducting magnetic resonance imaging (MRI) magnets have limited low-temperature stability.
• Effective management of external heat sources is crucial for these systems.
• A well-shielded gradient magnetic field is essential for optimal performance in cryogen-free MRI.

Purpose of the Study:

• To present an enhanced magnetic shielding method for cryogen-free MRI systems.
• To reduce stray magnetic field intensity without increasing system complexity.
• To develop engineering-feasible gradient coil schemes.

Main Methods:

• Implementation of a regionalized stray field constraining strategy.
• Optimization of constraint parameters for gradient coil design.
• Real-world measurement and performance evaluation in an integrated MRI system.

Main Results:

• The proposed method successfully reduced stray field intensity by 50%.
• Developed gradient coil schemes were engineering-feasible and did not increase system complexity.
• The enhanced gradient assembly demonstrated excellent performance, enabling high-quality image output.

Conclusions:

• The regionalized stray field constraining strategy is an effective method for improving cryogen-free MRI magnets.
• The developed design paradigm offers a practical approach for enhancing MRI system stability and performance.
• This method has the potential to significantly benefit future cryogen-free MRI magnet designs.