title: DC-gated high resolution three-dimensional lung imaging during free-breathing.
abstract: OBJECTIVE
  To use the acquisition of the k-space center signal (DC signal) implemented into a Cartesian three-dimensional (3D) FLASH sequence for retrospective respiratory self-gating and, thus, for the examination of the whole human lung in high spatial resolution during free breathing.
  
  
  METHODS
  Volunteer as well as patient measurements were performed under free breathing conditions. The DC signal is acquired after the actual image data acquisition within each excitation of a 3D FLASH sequence. The DC signal is then used to track respiratory motion for retrospective respiratory gating.
  
  
  RESULTS
  It is shown that the acquisition of the DC signal after the imaging module can be used in a 3D FLASH sequence to extract respiratory motion information for retrospective respiratory self-gating and allows for shorter echo times (TE) and therefore increased lung parenchyma SNR.
  
  
  CONCLUSIONS
  The acquisition of the DC signal after image signal acquisition allows successful retrospective gating, enabling the reconstruction of high resolution images of the whole human lung under free breathing conditions.
authors.affiliation: Department of Experimental Physics 5, University of Wuerzburg, Germany. sweick@physik.uni-wuerzburg.de
authors.forename: Stefan
authors.initials: S
authors.lastname: Weick
authors.forename: Felix A
authors.initials: FA
authors.lastname: Breuer
authors.forename: Philipp
authors.initials: P
authors.lastname: Ehses
authors.forename: Michael
authors.initials: M
authors.lastname: Völker
authors.forename: Christian
authors.initials: C
authors.lastname: Hintze
authors.forename: Jürgen
authors.initials: J
authors.lastname: Biederer
authors.forename: Peter M
authors.initials: PM
authors.lastname: Jakob
mesh_terms: D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008168:Lung / Q000473:pathology*; D008171:Lung Diseases / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods; D009068:Movement; D012119:Respiration; D055425:Respiratory-Gated Imaging Techniques / Q000379:methods*; D012189:Retrospective Studies; D059629:Signal-To-Noise Ratio