Liver fibrosis can be detected using intravoxel incoherent motion (IVIM) MRI techniques. For example, using a diffusion weighted MRI imaging sequence, scans of a patient's liver can be made. Signal intensity data acquired in MRI scans can be fitted to a bi-exponential model of signal attenuation representing a combination of a fast component associated with perfusion and a slow component associated with diffusion in the tissue. This allows the extraction of parameters representing the slow and fast diffusion rates, as well as the fractional contributions of the fast and slow components. Analysis of a combination of these parameters in a multi-dimensional space (e.g., in a three-dimensional space) yields a metric that can distinguish healthy liver from fibrotic liver.