title: Quantitative framework for prospective motion correction evaluation.
abstract: OBJECTIVE
  Establishing a framework to evaluate performances of prospective motion correction (PMC) MRI considering motion variability between MRI scans.
  
  
  METHODS
  A framework was developed to obtain quantitative comparisons between different motion correction setups, considering that varying intrinsic motion patterns between acquisitions can induce bias. Intrinsic motion was considered by replaying in a phantom experiment the recorded motion trajectories from subjects. T1-weighted MRI on five volunteers and two different marker fixations (mouth guard and nose bridge fixations) were used to test the framework. Two metrics were investigated to quantify the improvement of the image quality with PMC.
  
  
  RESULTS
  Motion patterns vary between subjects as well as between repeated scans within a subject. This variability can be approximated by replaying the motion in a distinct phantom experiment and used as a covariate in models comparing motion corrections. We show that considering the intrinsic motion alters the statistical significance in comparing marker fixations. As an example, two marker fixations, a mouth guard and a nose bridge, were evaluated in terms of their effectiveness for PMC. A mouth guard achieved better PMC performance.
  
  
  CONCLUSIONS
  Intrinsic motion patterns can bias comparisons between PMC configurations and must be considered for robust evaluations. A framework for evaluating intrinsic motion patterns in PMC is presented.
authors.affiliation: Center for Imaging of Neurodegenerative Diseases, Veteran Affairs Medical Center, San Francisco, California, USA.|Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA.
authors.forename: Nicolas A
authors.initials: NA
authors.lastname: Pannetier
authors.affiliation: Center for Imaging of Neurodegenerative Diseases, Veteran Affairs Medical Center, San Francisco, California, USA.|Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA.
authors.forename: Theano
authors.initials: T
authors.lastname: Stavrinos
authors.affiliation: Center for Imaging of Neurodegenerative Diseases, Veteran Affairs Medical Center, San Francisco, California, USA.|Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Ng
authors.affiliation: Department of Radiology, University Medical Center Freiburg, Freiburg, Germany.|Department of Radiology, JABSOM, Honolulu, Hawaii, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Herbst
authors.affiliation: Department of Radiology, University Medical Center Freiburg, Freiburg, Germany.
authors.forename: Maxim
authors.initials: M
authors.lastname: Zaitsev
authors.affiliation: Center for Imaging of Neurodegenerative Diseases, Veteran Affairs Medical Center, San Francisco, California, USA.|Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA.
authors.forename: Karl
authors.initials: K
authors.lastname: Young
authors.affiliation: Center for Imaging of Neurodegenerative Diseases, Veteran Affairs Medical Center, San Francisco, California, USA.|Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA.
authors.forename: Gerald
authors.initials: G
authors.lastname: Matson
authors.affiliation: Center for Imaging of Neurodegenerative Diseases, Veteran Affairs Medical Center, San Francisco, California, USA.|Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA.
authors.forename: Norbert
authors.initials: N
authors.lastname: Schuff
mesh_terms: D000328:Adult; D016477:Artifacts; D005260:Female; D006257:Head; D064368:Healthy Volunteers; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D008297:Male; D009038:Motion; D019047:Phantoms, Imaging; D059629:Signal-To-Noise Ratio
keywords: PMC; average edge strength; haralick texture; marker fixation; motion correction; prospective motion correction