Effect of Intravascular Contrast Agent on Diffusion and Perfusion Fraction Coefficients in the Peripheral Zone and Prostate Cancer

We present a systematic approach to characterize differences in pre- and post-contrast diffusion and perfusion parameters. In addition to measuring ADC values before and after contrast injection, we extended the mono-exponential model to incorporate the contribution of pseudo-perfusion to the signal intensity and evaluated the impact of contrast injection on molecular diffusion (D) and perfusion fraction (f). We find in PCa, the coefficient D, like ADC, was significantly lower on post-contrast as compared to pre-contrast DWI, while the perfusion fraction coefficient was significantly higher on post-contrast acquisitions. In PZ, ADC and D did not differ significantly between post- and pre-contrast acquisitions, but f was significantly higher after contrast injection.