Correlation of the R1 and R2 values of gadolinium-based MRI contrast media with the ΔHounsfield unit of CT contrast media of identical concentration

► We investigated four different types MRI and one CT contrast agent in vitro. ► We sought to establish relations between concentration, MRI relaxivity, CT Hounsfield unites. ► The concentration of Gd-based contrast media was examined in a SNR90% area that showed a T1 effect. ► The ΔHU of CT contrast media was exponentially increased depending on the concentration. ► High diagnosis image can be acquired from the information of MRI contrast media concentration.