Multi-band echo-planar spectroscopic imaging of hyperpolarized 13C probes in a compact preclinical PET/MR scanner

Abstract

Hyperpolarized (HP) 13C MRI requires advanced pulse sequences to capture the dynamic, localized metabolic information. We developed an echo planar spectroscopic imaging (EPSI) pulse sequence incorporating multi-band spectral-spatial radiofrequency (SSRF) pulses for rapid and efficient HP 13C MRI on a new cryogen-free simultaneous PET/MR molecular imaging platform with compact footprint. Excitation profiles were measured in phantoms, and the SSRF-EPSI sequence was tested in rats using two HP 13C probes. We also obtained simultaneous 18F-FDG-PET data for comparison. In conclusion, advanced 13C SSRF imaging approaches are feasible on the new PET/MR platform, facilitating direct comparison with PET.