Accelerated spectroscopic imaging of hyperpolarized C-13 pyruvate using SENSE parallel imaging

The ability to accelerate the spatial encoding process during a chemical shift imaging (CSI) scan of hyperpolarized compounds is demonstrated through parallel imaging. A hardware setup designed to simultaneously acquire (13)C data from multiple receivers is presented here. A system consisting of four preamplifiers, four gain stages, a transmit coil, and a four receive channel rat coil was built for single channel excitation and simultaneous multi-channel detection of (13)C signals. The hardware setup was integrated with commercial scanner electronics, allowing the system to function similar to a conventional proton multi-channel setup, except at a different frequency. The ability to perform parallel imaging is demonstrated in vivo. CSI data from the accelerated scans are reconstructed using a self-calibrated multi-spectral parallel imaging algorithm, by using lower resolution coil sensitivity maps obtained from the central region of k-space. The advantages and disadvantages of parallel imaging in the context of imaging hyperpolarized compounds are discussed.