title: Breast tissue decomposition with spectral distortion correction: a postmortem study.
abstract: OBJECTIVE
  To investigate the feasibility of an accurate measurement of water, lipid, and protein composition of breast tissue using a photon-counting spectral computed tomography (CT) with spectral distortion corrections.
  
  
  METHODS
  Thirty-eight postmortem breasts were imaged with a cadmium-zinc-telluride-based photon-counting spectral CT system at 100 kV. The energy-resolving capability of the photon-counting detector was used to separate photons into low and high energy bins with a splitting energy of 42 keV. The estimated mean glandular dose for each breast ranged from 1.8 to 2.2 mGy. Two spectral distortion correction techniques were implemented, respectively, on the raw images to correct the nonlinear detector response due to pulse pileup and charge-sharing artifacts. Dual energy decomposition was then used to characterize each breast in terms of water, lipid, and protein content. In the meantime, the breasts were chemically decomposed into their respective water, lipid, and protein components to provide a gold standard for comparison with dual energy decomposition results.
  
  
  RESULTS
  The accuracy of the tissue compositional measurement with spectral CT was determined by comparing to the reference standard from chemical analysis. The averaged root-mean-square error in percentage composition was reduced from 15.5% to 2.8% after spectral distortion corrections.
  
  
  CONCLUSIONS
  The results indicate that spectral CT can be used to quantify the water, lipid, and protein content in breast tissue. The accuracy of the compositional analysis depends on the applied spectral distortion correction technique.
authors.affiliation: Department of Radiological Sciences, University of California, Irvine, California 92697.
authors.forename: Huanjun
authors.initials: H
authors.lastname: Ding
authors.affiliation: Department of Radiological Sciences, University of California, Irvine, California 92697.
authors.forename: Bo
authors.initials: B
authors.lastname: Zhao
authors.affiliation: Department of Radiological Sciences, University of California, Irvine, California 92697.
authors.forename: Pavlo
authors.initials: P
authors.lastname: Baturin
authors.affiliation: Department of Radiological Sciences, University of California, Irvine, California 92697.
authors.forename: Farnaz
authors.initials: F
authors.lastname: Behroozi
authors.affiliation: Department of Radiological Sciences, University of California, Irvine, California 92697.
authors.forename: Sabee
authors.initials: S
authors.lastname: Molloi
mesh_terms: D001940:Breast / Q000737:chemistry*; D002104:Cadmium; D002138:Calibration; D005240:Feasibility Studies; D006801:Humans; D016014:Linear Models; D008055:Lipids / Q000032:analysis*; D017711:Nonlinear Dynamics; D019047:Phantoms, Imaging; D011506:Proteins / Q000032:analysis*; D013691:Tellurium; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*; D014867:Water / Q000032:analysis*; D015032:Zinc
chemical_list: C474490:CdZnTe; D008055:Lipids; D011506:Proteins; D002104:Cadmium; D014867:Water; D015032:Zinc; D013691:Tellurium