Alternative winding patterns for twisted solenoid coils with improved characteristics for TRASE MRI

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Coil Engineering
• Biophysics

Background:

• Transmit array spatial encoding (TRASE) utilizes B1 field phase gradients for MRI spatial encoding.
• TRASE offers potential advantages like hardware simplicity and reduced acoustic noise.
• Optimizing coil designs is crucial for TRASE system efficiency.

Purpose of the Study:

• To numerically assess and compare various winding patterns for twisted solenoid phase-gradient coils used in TRASE.
• To evaluate magnetic field uniformity and phase linearity of different coil configurations.
• To identify the most practical and efficient coil design for TRASE MRI.

Main Methods:

• Biot-Savart simulations were employed to analyze coil performance.
• Evaluated designs included standard twisted solenoids (with/without return wire), double-wound twisted solenoids, and discrete-loop twisted solenoids.
• Key performance metrics were magnetic field uniformity and phase linearity.

Main Results:

• Both double-wound and discrete-loop twisted solenoid designs showed improvements over existing TRASE coil configurations.
• The discrete-loop design demonstrated comparable performance to the double-wound design.
• The discrete-loop pattern requires significantly less wire material compared to the double-wound design.

Conclusions:

• The discrete-loop twisted solenoid design is a promising advancement for TRASE MRI systems.
• This design offers a balance of improved performance and reduced material requirements.
• The discrete-loop pattern is recommended for practical coil construction and operation in TRASE MRI.