New linear IVIM model yields accurate perfusion fraction, with fast fitting, image acquisition, and uncertainty estimates.

Motivation: Intra-voxel incoherent motion imaging (IVIM) suffers from long acquisition times due to the number of low b-values typically required, which limits clinical use. Goal(s): To develop a faster linearised method of IVIM modelling requiring fewer b-values to approximate the perfusion fraction with uncertainty estimation. Approach: Compare our linear IVIM fitting using 4 b-values and with conventional biexponential modelling using 8 b-values in 26 patients with retroperitoneal sarcoma. Results: Strong agreement in perfusion fraction estimates between the two models. Impact: The proposed linear model could estimate the perfusion fraction and associated uncertainty in a broader range of clinical applications where acquisition time may be constrained (body DWI for example).