title: The Role of Nonlinear Gradients in Parallel Imaging: A k-Space Based Analysis.
abstract: Sequences that encode the spatial information of an object using nonlinear gradient fields are a new frontier in MRI, with potential to provide lower peripheral nerve stimulation, windowed fields of view, tailored spatially-varying resolution, curved slices that mirror physiological geometry, and, most importantly, very fast parallel imaging with multichannel coils. The acceleration for multichannel images is generally explained by the fact that curvilinear gradient isocontours better complement the azimuthal spatial encoding provided by typical receiver arrays. However, the details of this complementarity have been more difficult to specify. We present a simple and intuitive framework for describing the mechanics of image formation with nonlinear gradients, and we use this framework to review some the main classes of nonlinear encoding schemes.
authors.affiliation: Department of Diagnostic Radiology, Yale University, New Haven, CT.
authors.forename: Gigi
authors.initials: G
authors.lastname: Galiana
authors.affiliation: Department of Biomedical Engineering, Yale University, New Haven, CT.
authors.forename: Jason P
authors.initials: JP
authors.lastname: Stockmann
authors.affiliation: Department of Biomedical Engineering, Yale University, New Haven, CT.
authors.forename: Leo
authors.initials: L
authors.lastname: Tam
authors.affiliation: Department of Diagnostic Radiology, Yale University, New Haven, CT.
authors.forename: Dana
authors.initials: D
authors.lastname: Peters
authors.affiliation: Department of Diagnostic Radiology, Yale University, New Haven, CT ; Department of Biomedical Engineering, Yale University, New Haven, CT.
authors.forename: Hemant
authors.initials: H
authors.lastname: Tagare
authors.affiliation: Department of Diagnostic Radiology, Yale University, New Haven, CT ; Department of Biomedical Engineering, Yale University, New Haven, CT ; Department of Neurosurgery, Yale University, New Haven, CT.
authors.forename: R Todd
authors.initials: RT
authors.lastname: Constable
keywords: O-Space; PatLoc; accelerated imaging; nonlinear imaging; parallel imaging