Patent ID: 7394252
Filing Date: 2008-07-01
Classification: G01R

Abstract:
1. A method for generating a fully sampled k-space data set corresponding to each of a plurality of receiver channels in a parallel MRI system having a plurality of corresponding receiver coil elements, the fully sampled k-space data sets corresponding to an image of a scanned subject using the parallel MRI system, the method comprising: (a) performing an undersampled GRAPPA scan of the subject using the set of receiver coil elements and corresponding receiver channels to obtain a reduced k-space data set, (b) obtaining a plurality of autocalibration samples in k-space for each receiver channel, (c) calculating a reconstruction kernel from the plurality of autocalibration samples and the reduced k-space data set, (d) formulating a Tikhonov regularization framework to allow a tradeoff between reliance on a conventional GRAPPA reconstruction which uses the reconstruction kernel and a replication of the prior k-space data from the plurality of autocalibration samples, with the tradeoff determined by an optimal regularization parameter; and (e) reconstructing missing k-space data to obtain a reconstructed k-space data set which together with the reduced data set fully samples each channel of k-space, the missing k-space data being reconstructed using one of a regularized GRAPPA reconstruction using the Tikhonov regularization framework and a conventional GRAPPA reconstruction, wherein for locations in the reconstructed k-space data set which correspond to locations of autocalibration samples included in the plurality of autocalibration samples, a regularized GRAPPA reconstruction is performed, and wherein conventional GRAPPA reconstructions are performed if no prior k-space data is available.