Experimental Assessment of the b-Matrix using a Reference Phantom in Diffusion Tensor Imaging

Purpose: Diffusion tensor imaging (DTI) has opened new possibilities to investigate the brain. It is, however, very important to know the exact diffusion weighting (spatial orientations and strengths) which is summarized in the so-called b-matrix. The coefficients of the b-matrix are usually calculated by using a simple equation which only takes into account the diffusion gradients and their spatial orientation. In this study we have determined the b-matrix analytically taking into account all gradients (including the imaging gradients). This leads to a system of equations with three unknown parameters (mean dif…