Validation of Intravoxel Incoherent Motion MRI using Perfused Explanted Human Livers

Motivation: Intravoxel incoherent motion (IVIM) is a promising technique for evaluation of diffusion and microvascular perfusion. Despite recent technical developments, systematic validation of IVIM remains challenging due to a lack of histologic and phantom studies. Goal(s): Evaluate the feasibility of using perfused explanted human livers from deceased donors for validation of IVIM. Approach: IVIM data was acquired in three explanted livers (two healthy; one cirrhotic) perfused through the portal vein and hepatic artery using different flow rates. Results: Diffusion coefficient was relatively independent of flow rate, while perfusion signal fraction, blood velocity standard deviation, and pseudo-diffusion coefficient demonstrated dependencies on flow rate. Impact: Perfused explanted human livers may serve as biologically accurate systems for validating quantitative IVIM techniques. Importantly, perfused explanted livers contain two distinct compartments (i.e., diffusion and perfusion components of the IVIM signal were independent and dependent on flow rate, respectively).