title: Generalized GRAPPA operators for wider spiral bands: rapid self-calibrated parallel reconstruction for variable density spiral MRI.
abstract: A rapid and self-calibrated parallel imaging reconstruction method is proposed for undersampled variable density spiral datasets. A set of generalized GRAPPA for wider readout line operators are used to expand each acquired spiral line into a wider spiral band, therefore fulfilling Nyquist sampling criterion throughout the k-space. The calibration of generalized GRAPPA for wider readout line operators is performed using the fully sampled central k-space region. The resulting generalized GRAPPA for wider readout line operator weights are adaptively regularized to minimize the error in the newly-generated data at different k-space locations. Simulation and experimental results demonstrate that the technique can be used either to achieve a significant acceleration and/or to reduce off-resonance artifacts due to a shorten readout duration.
authors.affiliation: Invivo Corporation, Philips Healthcare, Gainesville, Florida 32608, USA. wei.lin2@philips.com
authors.forename: Wei
authors.initials: W
authors.lastname: Lin
authors.forename: Peter
authors.initials: P
authors.lastname: Börnert
authors.forename: Feng
authors.initials: F
authors.lastname: Huang
authors.forename: George R
authors.initials: GR
authors.lastname: Duensing
authors.forename: Arne
authors.initials: A
authors.lastname: Reykowski
mesh_terms: D000465:Algorithms; D016477:Artifacts; D001931:Brain Mapping / Q000379:methods*; D002138:Calibration; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D019047:Phantoms, Imaging