The twisted solenoid RF phase gradient transmit coil for TRASE imaging

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Coil Design
• Radio-Frequency (RF) Engineering

Background:

• Transmit Array Spatial Encoding (TRASE) MRI utilizes radio-frequency (RF) or B1 transmit phase gradient fields for high spatial resolution.
• Efficient generation of B1 fields with uniform magnitude and strong phase gradients is crucial for TRASE MRI image quality.
• Existing coil designs may have limitations in generating the required B1 field characteristics or spatial encoding capabilities.

Purpose of the Study:

• To introduce a new family of phase gradient transmit coils for TRASE MRI.
• To investigate the geometric, electrical, and magnetic properties of the proposed coil design.
• To demonstrate the capability of the new coil design for spatial encoding along the main static B0 field.

Main Methods:

• Design and fabrication of a novel solenoid coil twisted about a transverse axis.
• Analytical calculations and numerical simulations to characterize coil performance.
• Experimental validation of the coil's performance, including 1D TRASE encoding.

Main Results:

• The twisted solenoid coil design exhibits favorable geometric, electrical, and magnetic properties.
• The coil enables spatial encoding along the B0 field direction without impeding bore access.
• Successful demonstration of 1D TRASE encoding was achieved without PIN diode switches.

Conclusions:

• The proposed twisted solenoid coil design significantly expands the capabilities of TRASE MRI.
• This coil innovation offers improved B1 field generation for enhanced spatial encoding.
• The design facilitates advanced MRI applications requiring high spatial resolution and flexible encoding strategies.