title: A sparse-projection computed tomography reconstruction method for in vivo application of in-line phase-contrast imaging.
abstract: BACKGROUND
  In recent years, X-ray phase-contrast imaging techniques have been extensively studied to visualize weakly absorbing objects. One of the most popular methods for phase-contrast imaging is in-line phase-contrast imaging (ILPCI). Combined with computed tomography (CT), phase-contrast CT can produce 3D volumetric images of samples. To date, the most common reconstruction method for phase-contrast X-ray CT imaging has been filtered back projection (FBP). However, because of the impact of respiration, lung slices cannot be reconstructed in vivo for a mouse using this method. Methods for reducing the radiation dose and the sampling time must also be considered.
  
  
  METHODS
  This paper proposes a novel method of in vivo mouse lung in-line phase-contrast imaging that has two primary improvements compared with recent methods: 1) using a compressed sensing (CS) theory-based CT reconstruction method for the in vivo in-line phase-contrast imaging application and 2) using the breathing phase extraction method to address the lung and rib cage movement caused by a live mouse's breathing.
  
  
  RESULTS
  Experiments were performed to test the breathing phase extraction method as applied to the lung and rib cage movement of a live mouse. Results with a live mouse specimen demonstrate that our method can reconstruct images of in vivo mouse lung.
  
  
  CONCLUSIONS
  The results demonstrate that our method could deal with vivo mouse's breathing and movements, meanwhile, using less sampling data than FBP while maintaining the same high quality.
authors.affiliation: College of Biomedical Engineering, Capital Medical University, You An Men, Beijing 100069, People's Republic of China.
authors.forename: Liting
authors.initials: L
authors.lastname: Wang
authors.forename: Xueli
authors.initials: X
authors.lastname: Li
authors.forename: Mingshu
authors.initials: M
authors.lastname: Wu
authors.forename: Lu
authors.initials: L
authors.lastname: Zhang
authors.forename: Shuqian
authors.initials: S
authors.lastname: Luo
mesh_terms: D000818:Animals; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional; D008168:Lung / Q000000981:diagnostic imaging / Q000502:physiology; D051379:Mice; D011829:Radiation Dosage; D012119:Respiration; D014057:Tomography, X-Ray Computed / Q000379:methods*
references.citation: Med Phys. 2013 Apr;40(4):041909
references.pmid: 23556903
references.citation: IEEE Trans Pattern Anal Mach Intell. 2005 Oct;27(10):1615-30
references.pmid: 16237996
references.citation: Eur J Radiol. 2008 Dec;68(3 Suppl):S22-6
references.pmid: 18599234
references.citation: Br J Radiol. 1997 May;70(833):437-9
references.pmid: 9227222
references.citation: J Synchrotron Radiat. 1998 May 1;5(Pt 3):1133-5
references.pmid: 15263769
references.citation: Phys Med Biol. 2004 Sep 21;49(18):4335-48
references.pmid: 15509069
references.citation: PLoS One. 2011 Feb 25;6(2):e17400
references.pmid: 21364899
references.citation: Yonsei Med J. 2009 Jun 30;50(3):422-6
references.pmid: 19568606
references.citation: Nat Med. 1996 Apr;2(4):473-5
references.pmid: 8597962
references.citation: Proc Natl Acad Sci U S A. 2012 Oct 30;109(44):17880-5
references.pmid: 23074250