Detection of acute kidney injury with hyperpolarized [13 C, 15 N]Urea and multiexponential relaxation modeling.

We demonstrate, for the first time, the differences in multiexponential behavior of [13 C, 15 N]urea between the healthy and ischemic rodent kidney. The distribution of relaxation pools were found to be both visually and numerically significantly different. The ability to improve the information level in hyperpolarized MR, by using the relaxation contrast mechanisms is an appealing option, that can easily be adopted in large animals and even in clinical studies in the near future.