title: Three-dimensional echo-planar cine imaging of cerebral blood supply using arterial spin labeling.
abstract: OBJECTIVE
  Echo-planar imaging (EPI) with CYlindrical Center-out spatiaL Encoding (EPICYCLE) is introduced as a novel hybrid three-dimensional (3D) EPI technique. Its suitability for the tracking of a short bolus created by pseudo-continuous arterial spin labeling (pCASL) through the cerebral vasculature is demonstrated.
  
  
  METHODS
  EPICYCLE acquires two-dimensional planes of k-space along center-out trajectories. These "spokes" are rotated from shot to shot about a common axis to encode a k-space cylinder. To track a bolus of labeled blood, the same subset of evenly distributed spokes is acquired in a cine fashion after a short period of pCASL. This process is repeated for all subsets to fill the whole 3D k-space of each time frame.
  
  
  RESULTS
  The passage of short pCASL boluses through the vasculature of a 3D imaging slab was successfully imaged using EPICYCLE. By choosing suitable sequence parameters, the impact of slab excitation on the bolus shape could be minimized. Parametric maps of signal amplitude, transit time, and bolus width reflected typical features of blood transport in large vessels.
  
  
  CONCLUSIONS
  The EPICYCLE technique was successfully applied to track a short bolus of labeled arterial blood during its passage through the cerebral vasculature.
authors.affiliation: Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstraße 1a, 04103, Leipzig, Germany.
authors.forename: Manoj
authors.initials: M
authors.lastname: Shrestha
authors.affiliation: Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstraße 1a, 04103, Leipzig, Germany. mildner@cbs.mpg.de.
authors.forename: Toralf
authors.initials: T
authors.lastname: Mildner
authors.affiliation: Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstraße 1a, 04103, Leipzig, Germany.
authors.forename: Torsten
authors.initials: T
authors.lastname: Schlumm
authors.affiliation: Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, USA.
authors.forename: Scott Haile
authors.initials: SH
authors.lastname: Robertson
authors.affiliation: Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstraße 1a, 04103, Leipzig, Germany.
authors.forename: Harald
authors.initials: H
authors.lastname: Möller
mesh_terms: D000328:Adult; D000465:Algorithms; D001158:Arteries / Q000000981:diagnostic imaging* / Q000503:physiopathology; D001921:Brain / Q000098:blood supply; D002560:Cerebrovascular Circulation; D017352:Echo-Planar Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D059629:Signal-To-Noise Ratio; D013113:Spin Labels
chemical_list: D013113:Spin Labels
keywords: Cerebral arteries; Cine magnetic resonance imaging; Echo-planar imaging; Perfusion imaging