High-T-c superconducting rf receiver coils for magnetic resonance imaging of small animals

We report on an HTS rf receiver surface probe designed for 2-Tesla MRI imag ing of spinal cord injuries in small animals. The 2-T probe is used in lieu of an implanted copper coil being currently used in research on spinal cor d injuries. The HTS probe was designed with a virtual ground plane, thus re ducing the coil-to-ground losses and making its unloaded quality factor and resonant frequency less sensitive to body proximity. Each coil was fabrica ted using patterned double-sided YBa2Cu3Ox (YBCO) films deposited either on sapphire or LaAlO3 substrates. The signal-to-noise ratio (SNR) was analyze d numerically using complete solutions to Maxwell's equations and the recip rocity principle for a rectangular coil next to a finite lossy dielectric c ylinder. A comparison of images obtained with superconducting and cooled co pper probes is shown.