Mechanical stress applied on a living body influences the structure and function of the living body, and knowledge of the spatial distribution of stress in the living body is important for study of a new treatment or prevention of diseases. The mechanical stress has a close relationship to the strain. In this paper, we propose a method to estimate strain distribution in the living body based on the diffusion tensor magnetic resonance imaging technique. The computer simulation and animal experiments showed that the apparent diffusion coefficient (ADC) in the direction of cell compressing decreased when cells were compressed. The smaller the cross-sectional area of cells became, the more mean diffusivity decreased. The change of cells reflects diffusion anisotropy. From these results, we concluded that strain in a living body can be estimated using MRI.
