Both diffusion and perfusion can be quantified or estimated separately by multi-b values according to a bi-exponential model, including D, f, and D*, which represent the pure diffusion coefficient, perfusion fraction, and pseudodiffusion coefficient, respectively.
Measurement reproducibility of perfusion fraction and pseudodiffusion coefficient derived by intravoxel incoherent motion diffusion-weighted MR imaging in normal liver and metastases.
The effect of low b-values on the intravoxel incoherent motion derived pseudodiffusion parameter in liver.
sup] The ADC values behaved as a weight of the pure diffusion and pseudodiffusion, pure diffusion restriction was mainly depending on the cellularity which was increasing during fibrogenic process, [sup] hence the increasing of pseudodiffusion should be responsible for the ADC upward alteration.
sup] The water movement within extracellular space is modeled as pure diffusivity when DWI are acquired with higher b value (over 600-800 s/mm [sup]2 ), while the microapillary perfusion and tubular flow are classified as pseudodiffusion, which is predominant with low b values (under 100-200 s/mm [sup]2 ).