Quadrature radio frequency coil for magnetic resonance imaging of the wrist at 4T

A magnetic resonance imaging (MRI) quadrature transmit/receive radio frequency (RF) coil for the purpose of imaging the human wrist in high resolution is outlined. The proposed design is used in a nonconventional manner within the bore of the MRI scanner. Due to restrictions of field linearity, space, and patient comfort, it was deemed necessary to design a coil that can be placed above the head with the arm aligned in the transverse plane of the magnet. This configuration allows the placement of the coil to be near the isocenter of the magnet, away from static field impurities. The RF wrist coil was built and a phantom study was conducted to establish signal-to-noise (SNR) performance and coil uniformity. Our design resulted in a peak SNR of 150 and sufficient uniformity for our application. Subsequent imaging of the human wrist provided excellent detail of the anatomy of interesta??i.e., the carpal tunnel.