title: Magnetic resonance fingerprinting using echo-planar imaging: Joint quantification of T1and T2∗ relaxation times.
abstract: To develop an implementation of the magnetic resonance fingerprinting (MRF) paradigm for quantitative imaging using echo-planar imaging (EPI) for simultaneous assessment of T1and T2∗.
  
  
  
  The proposed MRF method (MRF-EPI) is based on the acquisition of 160 gradient-spoiled EPI images with rapid, parallel-imaging accelerated, Cartesian readout and a measurement time of 10 s per slice. Contrast variation is induced using an initial inversion pulse, and varying the flip angles, echo times, and repetition times throughout the sequence. Joint quantification of T1and T2∗ is performed using dictionary matching with integrated B1+ correction. The quantification accuracy of the method was validated in phantom scans and in vivo in 6 healthy subjects.
  
  
  
  Joint T1and T2∗ parameter maps acquired with MRF-EPI in phantoms are in good agreement with reference measurements, showing deviations under 5% and 4% for T1and T2∗, respectively. In vivo baseline images were visually free of artifacts. In vivo relaxation times are in good agreement with gold-standard techniques (deviation T1: 4 ± 2%, T2∗: 4 ± 5%). The visual quality was comparable to the in vivo gold standard, despite substantially shortened scan times.
  
  
  
  The proposed MRF-EPI method provides fast and accurate T1and T2∗ quantification. This approach offers a rapid supplement to the non-Cartesian MRF portfolio, with potentially increased usability and robustness. Magn Reson Med 78:1724-1733, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
authors.affiliation: Computer Assisted Clinical Medicine, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany.
authors.forename: Benedikt
authors.initials: B
authors.lastname: Rieger
authors.affiliation: Computer Assisted Clinical Medicine, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany.
authors.forename: Fabian
authors.initials: F
authors.lastname: Zimmer
authors.affiliation: Computer Assisted Clinical Medicine, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany.
authors.forename: Jascha
authors.initials: J
authors.lastname: Zapp
authors.affiliation: Computer Assisted Clinical Medicine, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany.|Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota, United States.|Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota, United States.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Weingärtner
authors.affiliation: Computer Assisted Clinical Medicine, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany.
authors.forename: Lothar R
authors.initials: LR
authors.lastname: Schad
mesh_terms: D000328:Adult; D000465:Algorithms; D001921:Brain / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D019047:Phantoms, Imaging; D055815:Young Adult
keywords: T1; 
  T2∗; echo-planar imaging; magnetic resonance fingerprinting; relaxometry