title: Single shot three-dimensional pulse sequence for hyperpolarized13C MRI.
abstract: Metabolic imaging with hyperpolarized13C-labeled cell substrates is a promising technique for imaging tissue metabolism in vivo. However, the transient nature of the hyperpolarization, and its depletion following excitation, limits the imaging time and the number of excitation pulses that can be used. We describe here a single-shot three-dimensional (3D) imaging sequence and demonstrate its capability to generate13C MR images in tumor-bearing mice injected with hyperpolarized [1-13C]pyruvate.
  
  
  
  The pulse sequence acquires a stack-of-spirals at two spin echoes after a single excitation pulse and encodes the kz-dimension in an interleaved manner to enhance robustness to B0inhomogeneity. Spectral-spatial pulses are used to acquire dynamic 3D images from selected hyperpolarized13C-labeled metabolites.
  
  
  
  A nominal spatial/temporal resolution of 1.25 × 1.25 × 2.5 mm3× 2 s was achieved in tumor images of hyperpolarized [1-13C]pyruvate and [1-13C]lactate acquired in vivo. Higher resolution in the z-direction, with a different k-space trajectory, was demonstrated in measurements on a thermally polarized [1-13C]lactate phantom.
  
  
  
  The pulse sequence is capable of imaging hyperpolarized13C-labeled substrates at relatively high spatial and temporal resolutions and is robust to moderate system imperfections. Magn Reson Med 77:740-752, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
authors.affiliation: Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, United Kingdom.
authors.forename: Jiazheng
authors.initials: J
authors.lastname: Wang
authors.affiliation: Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, United Kingdom.
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Wright
authors.affiliation: Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, United Kingdom.
authors.forename: De-En
authors.initials: DE
authors.lastname: Hu
authors.affiliation: Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, United Kingdom.
authors.forename: Richard
authors.initials: R
authors.lastname: Hesketh
authors.affiliation: Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, United Kingdom.|Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, United Kingdom.
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Brindle
mesh_terms: D000818:Animals; D002247:Carbon Isotopes / Q000737:chemistry / Q000378:metabolism*; D005260:Female; D021621:Imaging, Three-Dimensional / Q000379:methods*; D019344:Lactic Acid / Q000737:chemistry / Q000378:metabolism; D008279:Magnetic Resonance Imaging / Q000379:methods*; D051379:Mice; D008810:Mice, Inbred C57BL; D009374:Neoplasms, Experimental / Q000000981:diagnostic imaging; D019047:Phantoms, Imaging; D019289:Pyruvic Acid / Q000737:chemistry / Q000378:metabolism
chemical_list: D002247:Carbon Isotopes; D019344:Lactic Acid; D019289:Pyruvic Acid
keywords: imaging; lactate; metabolism; pyruvate; spiral trajectory; tumors