title: Single and double acquisition strategies for compensation of artifacts from eddy current and transient oscillation in balanced steady-state free precession.
abstract: To develop single and double acquisition methods to compensate for artifacts from eddy currents and transient oscillations in balanced steady-state free precession (bSSFP) with centric phase-encoding (PE) order for magnetization-prepared bSSFP imaging.
  
  
  
  A single and four different double acquisition methods were developed and evaluated with Bloch equation simulations, phantom/in vivo experiments, and quantitative analyses. For the single acquisition method, multiple PE groups, each of which was composed of N linearly changing PE lines, were ordered in a pseudocentric manner for optimal contrast and minimal signal fluctuations. Double acquisition methods used complex averaging of two images that had opposite artifact patterns from different acquisition orders or from different numbers of dummy scans.
  
  
  
  Simulation results showed high sensitivity of eddy-current and transient-oscillation artifacts to off-resonance frequency and PE schemes. The artifacts were reduced with the PE-grouping with N values from 3 to 8, similar to or better than the conventional pairing scheme of N = 2. The proposed double acquisition methods removed the remaining artifacts significantly. The proposed methods conserved detailed structures in magnetization transfer imaging well, compared with the conventional methods.
  
  
  
  The proposed single and double acquisition methods can be useful for artifact-free magnetization-prepared bSSFP imaging with desired contrast and minimized dummy scans. Magn Reson Med 78:254-263, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
authors.affiliation: MRI Laboratory, Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Korea.
authors.forename: Hyun-Soo
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Seung Hong
authors.initials: SH
authors.lastname: Choi
authors.affiliation: MRI Laboratory, Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Korea.
authors.forename: Sung-Hong
authors.initials: SH
authors.lastname: Park
mesh_terms: D000465:Algorithms; D016477:Artifacts; D001921:Brain / Q000000981:diagnostic imaging*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D009991:Oscillometry / Q000379:methods; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique
keywords: artifact compensation; balanced steady-state free precession; eddy current; phase-encoding grouping; pseudocentric; transient oscillation