title: Combined geometric and algebraic solutions for removal of bSSFP banding artifacts with performance comparisons.
abstract: Balanced steady state free precession (bSSFP) imaging suffers from off-resonance artifacts such as signal modulation and banding. Solutions for removal of bSSFP off-resonance dependence are described and compared, and an optimal solution is proposed.
  
  
  
  An Algebraic Solution (AS) that complements a previously described Geometric Solution (GS) is derived from four phase-cycled bSSFP datasets. A composite Geometric-Algebraic Solution (GAS) is formed from a noise-variance-weighted average of the AS and GS images. Two simulations test the solutions over a range of parameters, and phantom and in vivo experiments are implemented. Image quality and performance of the GS, AS, and GAS are compared with the complex sum and a numerical parameter estimation algorithm.
  
  
  
  The parameter estimation algorithm, GS, AS, and GAS remove most banding and signal modulation in bSSFP imaging. The variable performance of the GS and AS on noisy data justifies generation of the GAS, which consistently provides the highest performance.
  
  
  
  The GAS is a robust technique for bSSFP signal demodulation that balances the regional efficacy of the GS and AS to remove banding, a feat not possible with prevalent techniques. Magn Reson Med 77:644-654, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
authors.affiliation: Department of Radiology, University of Washington, Seattle, Washington, USA.
authors.forename: Michael N
authors.initials: MN
authors.lastname: Hoff
authors.affiliation: Department of Radiology, University of Washington, Seattle, Washington, USA.
authors.forename: Jalal B
authors.initials: JB
authors.lastname: Andre
authors.affiliation: Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada.|Department of Radiology, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Qing-San
authors.initials: QS
authors.lastname: Xiang
mesh_terms: D000465:Algorithms; D016477:Artifacts; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: algebraic solution; bSSFP imaging; banding artifact; geometric solution; noise-variance weighting; phase cycling