A method includes concurrently modulating administration of at least two different contrast agents to a subject during an imaging procedure based on a modulation profile. The at least two different contrast agents exhibit different spectral characteristics. The method further includes performing a spectral decomposition of data indicative of the at least two different contrast agents, determining concentrations of the at least two different contrast agents based on the spectral reconstruction, and determining a perfusion parameter based on a ratio of the concentrations and the modulation profile.
