A 9.4 Tesla Transmit and Receive MRI Quadrature Birdcage Coil Design and Fabrication for Mouse imaging

Abstract

Magnetic Resonance Imaging (MRI) is an image modality used for clinical diagnosis as well as animal research. The study described in this thesis is intended for animal MRI application. In order to acquire high-resolution MRI images, radio-frequency (RF) coils are necessary in the experiments. In this study, we designed and fabricated a 9.4 Tesla high-pass transmit and receive birdcage coil for fMRI mouse imaging. The function of this system is to transmit RF energy to the subject generating a homogeneous volume B1+ field and then receive the RF energy with a pretty high SNR. The coil was designed by applying software simulations at first. Taken care of tuning, matching and other practical issues, the hardware implementation was done. Meanwhile, the front end for this system which includes T/R switch, Quadrature Hybrid, and LNA is discussed. By the end, MRI images of a saline water phantom acquired with the fabricated coil in a 9.4 Tesla MRI scanner demonstrate a high-level of excitation homogeneity and SNR, which correspond very well to the theory and simulation results.