Improving sodium Magnetic Resonance in humans by design of a dedicated 23Na surface coil

Abstract Sodium MRI is a powerful tool for providing biochemical information on the tissue viability, cell integrity and function in quantitative and noninvasive manner and it has already been applied in vivo in most human tissues. Although it could provide useful and new information not available with classic proton MRI, the low detectable sodium signal gives rise to technological limitations in terms of data quality when using clinical scanners. The design of dedicated coils capable of providing large field of view with high Signal-to-Noise Ratio (SNR) data is of fundamental importance. This work presents magnetostatic simulation, test and application of a transmit/receive circular coil designed for 23 Na MR experiments in phantoms and humans with a clinical 3T scanner. In particular, the paper provides details of the design, modeling and construction of the coil. Such coil prototype was tested at workbench by using a dual-loop probe and a network analyzer, for quality factors and Q ratios measurements. Finally, the coil was employed in MR experiments to acquire phantom and in vivo data on different human organs (heart, kidney, calf and brain).