Not yet reviewed by Pith; the record is open.

Hyperpolarized 13C Magnetic Resonance Spectroscopic Imaging (HP 13C-MRSI) has the potential to greatly improve diagnostic radiology thanks to its unique capability to detect, noninvasively, a wide range of diseases entailing aberrant metabolism. Nevertheless, it struggles to enter everyday clinical practice as an alternative and/or complement to Positron Emission Tomography (PET). Because of the minute-long hyperpolarization lifetime of the MR HP contrast agents, one of the reasons is, differently from PET, the need and financial burden to have the polarizing machine on site and, as close as possible to the MR scanner. In this work, we show that dDNP samples prepared with UV-induced labile radicals can bridge the technical gap with PET and provide MRI facilities with hours-long relaxing HP contrast agents. As a demonstration, we show the first across cities HP 13C-MRSI experiment in vivo and on a clinical scanner for a perfusion/angiography ([1-13C]HP001) and a metabolic ([U-13C, d7]glucose) contrast agent.