title: Combining phase images from array coils using a short echo time reference scan (COMPOSER).
abstract: To develop a simple method for combining phase images from multichannel coils that does not require a reference coil and does not entail phase unwrapping, fitting or iterative procedures.
  
  
  
  At very short echo time, the phase measured with each coil of an array approximates to the phase offset to which the image from that coil is subject. Subtracting this information from the phase of the scan of interest matches the phases from the coils, allowing them to be combined. The effectiveness of this approach is quantified in the brain, calf and breast with coils of diverse designs.
  
  
  
  The quality of phase matching between coil elements was close to 100% with all coils assessed even in regions of low signal. This method of phase combination was similar in effectiveness to the Roemer method (which needs a reference coil) and was superior to the rival reference-coil-free approaches tested.
  
  
  
  The proposed approach-COMbining Phase data using a Short Echo-time Reference scan (COMPOSER)-is a simple and effective approach to reconstructing phase images from multichannel coils. It requires little additional scan time, is compatible with parallel imaging and is applicable to all coils, independent of configuration. Magn Reson Med 77:318-327, 2017. © 2015 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine.
authors.affiliation: High Field Magnetic Resonance Centre, Medical University of Vienna, Austria.|Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria.
authors.forename: Simon Daniel
authors.initials: SD
authors.lastname: Robinson
authors.affiliation: High Field Magnetic Resonance Centre, Medical University of Vienna, Austria.|Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria.
authors.forename: Barbara
authors.initials: B
authors.lastname: Dymerska
authors.affiliation: High Field Magnetic Resonance Centre, Medical University of Vienna, Austria.|Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Bogner
authors.affiliation: The University of Queensland, Centre for Advanced Imaging, Brisbane, Australia.
authors.forename: Markus
authors.initials: M
authors.lastname: Barth
authors.affiliation: High Field Magnetic Resonance Centre, Medical University of Vienna, Austria.|Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria.
authors.forename: Olgica
authors.initials: O
authors.lastname: Zaric
authors.affiliation: High Field Magnetic Resonance Centre, Medical University of Vienna, Austria.|Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria.
authors.forename: Sigrun
authors.initials: S
authors.lastname: Goluch
authors.affiliation: High Field Magnetic Resonance Centre, Medical University of Vienna, Austria.|Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria.
authors.forename: Günther
authors.initials: G
authors.lastname: Grabner
authors.affiliation: Department of Radiology, Division of Radiological Physics, University of Basel Hospital, Basel, Switzerland.|Department of Biomedical Engineering, University of Basel, Switzerland.
authors.forename: Xeni
authors.initials: X
authors.lastname: Deligianni
authors.affiliation: Department of Radiology, Division of Radiological Physics, University of Basel Hospital, Basel, Switzerland.|Department of Biomedical Engineering, University of Basel, Switzerland.
authors.forename: Oliver
authors.initials: O
authors.lastname: Bieri
authors.affiliation: High Field Magnetic Resonance Centre, Medical University of Vienna, Austria.|Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria.
authors.forename: Siegfried
authors.initials: S
authors.lastname: Trattnig
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging; D001940:Breast / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007866:Leg / Q000000981:diagnostic imaging; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D059629:Signal-To-Noise Ratio
keywords: parallel transmit; phase combination; phase imaging; phased array coils; ultra-high field