UCSF

Hyperpolarized [1-13C]pyruvate magnetic resonance imaging is a novel imaging modality used to study real-time metabolic conversions in vivo. The 13C label is conserved in downstream metabolites of pyruvate, including lactate and bicarbonate in the brain, and the measurement of these metabolic conversions provides unique measurements of cerebral bioenergetics that can provide biomarkers of brain tumor metabolic reprogramming and response to therapy. Upregulated pyruvate to lactate conversion via glycolysis, known as the Warburg effect, is associated with cancer cell metabolism. Hyperpolarized [1-13C]pyruvate magnetic resonance imaging provides a valuable technique for measuring metabolic activity, but it comes with challenges due to the rapid decay of nonrenewable polarization. Hyperpolarization enhances the signal of [1-13C]pyruvate 10,000-fold compared to thermal equilibrium but the signal decays after pyruvate is taken out of the polarizer according to a decay constant characterized by T1, which is approximately one minute. This dissertation presents novel and improved analysis methods for hyperpolarized 13C imaging demonstrated in multiple clinical studies, including metabolic quantification of multi-resolution images, reproducible metabolic measurement methods across multiple research sites, and cerebral perfusion measurement using hyperpolarized [1-13C]pyruvate imaging. Further methods to improve the acquisition of hyperpolarized [1-13C]pyruvate imaging are also presented, including the characterization of polarizer quality control statistics, frequency response of spatial-spectral pulses, and the signal effects of reconstructing hyperpolarized [1-13C]pyruvate data with different types of sensitivity maps.