title: Technical Note: Synchrotron-based high-energy x-ray phase sensitive microtomography for biomedical research.
abstract: OBJECTIVE
  Propagation-based phase-contrast CT (PPCT) utilizes highly sensitive phase-contrast technology applied to x-ray microtomography. Performing phase retrieval on the acquired angular projections can enhance image contrast and enable quantitative imaging. In this work, the authors demonstrate the validity and advantages of a novel technique for high-resolution PPCT by using the generalized phase-attenuation duality (PAD) method of phase retrieval.
  
  
  METHODS
  A high-resolution angular projection data set of a fish head specimen was acquired with a monochromatic 60-keV x-ray beam. In one approach, the projection data were directly used for tomographic reconstruction. In two other approaches, the projection data were preprocessed by phase retrieval based on either the linearized PAD method or the generalized PAD method. The reconstructed images from all three approaches were then compared in terms of tissue contrast-to-noise ratio and spatial resolution.
  
  
  RESULTS
  The authors' experimental results demonstrated the validity of the PPCT technique based on the generalized PAD-based method. In addition, the results show that the authors' technique is superior to the direct PPCT technique as well as the linearized PAD-based PPCT technique in terms of their relative capabilities for tissue discrimination and characterization.
  
  
  CONCLUSIONS
  This novel PPCT technique demonstrates great potential for biomedical imaging, especially for applications that require high spatial resolution and limited radiation exposure.
authors.affiliation: Japan Synchrotron Radiation Research Institute, SPring-8, 1-1-1 Kouto, Sayo, Hyogo 679-5198, Japan.
authors.forename: Huiqiang
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama 35249.
authors.forename: Xizeng
authors.initials: X
authors.lastname: Wu
authors.affiliation: Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
authors.forename: Tiqiao
authors.initials: T
authors.lastname: Xiao
mesh_terms: D035843:Biomedical Research; D059629:Signal-To-Noise Ratio; D017356:Synchrotrons; D055114:X-Ray Microtomography / Q000295:instrumentation*