Accelerating functional MRI using fixed-rank approximations and radial-cartesian sampling.

ABSTRACT:

Purpose

Recently, k-t FASTER (fMRI Accelerated in Space-time by means of Truncation of Effective Rank) was introduced for rank-constrained acceleration of fMRI data acquisition. Here we demonstrate improvements achieved through a hybrid three-dimensional radial-Cartesian sampling approach that allows posthoc selection of acceleration factors, as well as incorporation of coil sensitivity encoding in the reconstruction.

Methods

The multicoil rank-constrained reconstruction used hard thresholding and shrinkage on matrix singular values of the space-time data matrix, using sensitivity encoding and the nonuniform Fast Fourier Transform to enforce data consistency in the multicoil non-Cartesian k-t domain. Variable acceleration factors were made possible using a radial increment b

SUBMITTER: Chiew M 

PROVIDER: S-EPMC4847647 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature