Mri Coils Optimized For Detection Of H-1 And Na-23 At 0.5 T

Experiments on proton and sodium MRI at 0.5 T are described to assess the sensitivity of various types of coils, namely solenoidal, surface, volumetric, and with specific complex geometry. Each type of coil, characterized by its geometric specificity, was built to record MR signal of protons (H-1) and sodium (Na-23) at 21.1 MHz and 5.6 MHz, respectively. Sodium coils were initially built for H-1 MRI and modified for Na-23 MRI. Measurements in a container phantom filled with a 12% salt solution showed that the quality factor and sensitivity of various type coils approximately coincide at both sodium and proton resonance frequencies. The possibility of using data on SNR for a highly concentrated sample and Q-factor measurements to predict MRI results for a weakly concentrated sample is considered. These measurements represent a guide for extension to multinuclear whole body low field MRI clinical platform that is usually designed to operate in proton mode only.