title: Accelerating multidimensional NMR and MRI experiments using iterated maps.
abstract: Techniques that accelerate data acquisition without sacrificing the advantages of fast Fourier transform (FFT) reconstruction could benefit a wide variety of magnetic resonance experiments. Here we discuss an approach for reconstructing multidimensional nuclear magnetic resonance (NMR) spectra and MR images from sparsely-sampled time domain data, by way of iterated maps. This method exploits the computational speed of the FFT algorithm and is done in a deterministic way, by reformulating any a priori knowledge or constraints into projections, and then iterating. In this paper we explain the motivation behind this approach, the formulation of the specific projections, the benefits of using a 'QUasi-Even Sampling, plus jiTter' (QUEST) sampling schedule, and various methods for handling noise. Applying the iterated maps method to real 2D NMR and 3D MRI of solids data, we show that it is flexible and robust enough to handle large data sets with significant noise and artifacts.
authors.affiliation: Department of Physics, Yale University, New Haven, CT 06511, United States.
authors.forename: Merideth A
authors.initials: MA
authors.lastname: Frey
authors.affiliation: Department of Physics, Princeton University, Princeton, NJ 08540, United States.
authors.forename: Zachary M
authors.initials: ZM
authors.lastname: Sethna
authors.affiliation: Department of Chemistry, Yale University, New Haven, CT 06511, United States.
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Manley
authors.affiliation: Department of Chemistry, Yale University, New Haven, CT 06511, United States.
authors.forename: Suvrajit
authors.initials: S
authors.lastname: Sengupta
authors.affiliation: Department of Chemistry, Yale University, New Haven, CT 06511, United States.
authors.forename: Kurt W
authors.initials: KW
authors.lastname: Zilm
authors.affiliation: Department of Chemistry, Yale University, New Haven, CT 06511, United States; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, United States.
authors.forename: J Patrick
authors.initials: JP
authors.lastname: Loria
authors.affiliation: Department of Physics, Yale University, New Haven, CT 06511, United States. Electronic address: sean.barrett@yale.edu.
authors.forename: Sean E
authors.initials: SE
authors.lastname: Barrett
mesh_terms: D000465:Algorithms; D000596:Amino Acids / Q000737:chemistry; D000619:Aminohydrolases / Q000737:chemistry; D016477:Artifacts; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000706:statistics & numerical data; D009682:Magnetic Resonance Spectroscopy / Q000379:methods* / Q000706:statistics & numerical data; D019906:Nuclear Magnetic Resonance, Biomolecular
chemical_list: D000596:Amino Acids; C087227:imidazole glycerol phosphate synthase; D000619:Aminohydrolases
keywords: Iterative maps; Magnetic resonance imaging; Multi-dimensional nuclear magnetic resonance; Sparse sampling