Multi-band frequency encoding method for metabolic imaging with hyperpolarized [1- ¹³C]pyruvate

A new method was developed for simultaneous spatial localization and spectral separation of multiple compounds based on a single echo, by designing the acquisition to place individual compounds in separate frequency encoding bands. This method was specially designed for rapid and robust metabolic imaging of hyperpolarized ¹³C substrates and their metabolic products, and was investigated in phantom studies and studies in normal mice and transgenic models of prostate cancer to provide rapid metabolic imaging of hyperpolarized [1- ¹³C]pyruvate and its metabolic products [1- ¹³C]lactate and [1- ¹³C]alanine at spatial resolutions up to 3 mm in-plane. Elevated pyruvate and lactate signals in the vicinity of prostatic tissues were observed in transgenic tumor mice. The multi-band frequency encoding technique enabled rapid metabolic imaging of hyperpolarized ¹³C compounds with important advantages over prior approaches, including less complicated acquisition and reconstruction methods.