Characterization, performances and in-vivo validation of a new dual-frequency NMR sensor

We address in this paper the design and performances of a home-built and dedicated double-tuned RF probe-head for the MRI in the rat. This probe-head consists of three decoupled RF coils. The field of applications is actually large. The immediate application may concerns the MRI of sodium-23 (²³Na) and later the MRI of xenon-129 (¹²⁹Xe) in the rat brain. The paper will focus on the characterization and the obtained performances as well as on the in-vivo validation of the probe. One of the underlying ideas is to make this probe easy to replicate, by other groups, with a low-cost, minimum development time and accepted performances. This is why we describe in some details the practical aspects of the workbench design and the coil characterization. The probe is validated at the ¹H and the ²³Na frequencies (100 MHz and 26.4 MHz at 2.35 T). In vivo MRI images of the rat brain were obtained at the ¹H frequency as well as NMR signals at the ²³Na frequency.