DTI measures the anisotropic diffusion of water molecules. In tissues like white matter, water diffusion is directionally dependent due to the organization of axonal fibers. By applying multiple diffusion gradients in various directions, DTI quantifies the directional preference of diffusion, producing a tensor that describes the magnitude and orientation of diffusion. Key metrics derived from DTI include fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD).
