Reduced Encoding Persistent Angular Structure

Introduction Persistent angular structure (PAS) MRI [1] is one of many approaches that recover complex white matter fibre configurations within single voxels of high angular resolution diffusion MRI (HARDI) data. It continues to exhibit impressive performance compared to other state of the art methods [2], but at the expense of unreasonably long reconstruction times. Here, we propose and test a simple adaptation to the algorithm that makes computation time manageable without significantly affecting performance. Method PAS MRI may be thought of as a spherical deconvolution algorithm [3, 4], which models the measurement A, at wavevector q, as the convolution of the fibre orientation distribution (FOD) with a response function R over the unit sphere: