title: Interior tomographic imaging of mouse heart in a carbon nanotube micro-CT.
abstract: The relatively high radiation dose from micro-CT is a cause for concern in preclinical research involving animal subjects. Interior region-of-interest (ROI) imaging was proposed for dose reduction, but has not been experimentally applied in micro-CT.
  
  
  
  Our aim is to implement interior ROI imaging in a carbon nanotube (CNT) x-ray source based micro-CT, and present the ROI image quality and radiation dose reduction for interior cardiac micro-CT imaging of a mouse heart in situ.
  
  
  
  An aperture collimator was mounted at the source-side to induce a small-sized cone beam (10 mm width) at the isocenter. Interior in situ micro-CT scans were conducted on a mouse carcass and several micro-CT phantoms. A GPU-accelerated hybrid iterative reconstruction algorithm was employed for volumetric image reconstruction. Radiation dose was measured for the same system operated at the interior and global micro-CT modes.
  
  
  
  Visual inspection demonstrated comparable image quality between two scan modes. Quantitative evaluation demonstrated high structural similarity index (up to 0.9614) with improved contrast-noise-ratio (CNR) on interior micro-CT mode. Interior micro-CT mode yielded significant reduction (up to 83.9%) for dose length product (DLP).
  
  
  
  This work demonstrates the applicability of using CNT x-ray source based interior micro-CT for preclinical imaging with significantly reduced radiation dose.
authors.affiliation: Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
authors.forename: Hao
authors.initials: H
authors.lastname: Gong
authors.affiliation: Virginia Tech-Wake Forest School of Biomedical Engineering and Science, Wake Forest University Health Sciences, Winston-Salem, NC, USA.|Department of Electrical and Computer Engineering, University of Massachusetts Lowell, Lowell, MA, USA.
authors.forename: Rui
authors.initials: R
authors.lastname: Liu
authors.affiliation: Department of Electrical and Computer Engineering, University of Massachusetts Lowell, Lowell, MA, USA.
authors.forename: Hengyong
authors.initials: H
authors.lastname: Yu
authors.affiliation: Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
authors.forename: Jianping
authors.initials: J
authors.lastname: Lu
authors.affiliation: Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
authors.forename: Otto
authors.initials: O
authors.lastname: Zhou
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, VA, USA.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Kan
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, VA, USA.
authors.forename: Jia-Qiang
authors.initials: JQ
authors.lastname: He
authors.affiliation: Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
authors.forename: Guohua
authors.initials: G
authors.lastname: Cao
mesh_terms: D000465:Algorithms; D000818:Animals; D006321:Heart / Q000000981:diagnostic imaging*; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D051379:Mice; D037742:Nanotubes, Carbon / Q000737:chemistry*; D019047:Phantoms, Imaging; D055114:X-Ray Microtomography / Q000379:methods*
chemical_list: D037742:Nanotubes, Carbon
keywords: Micro-CT; carbon-nanotube x-ray micro-CT; interior tomography