title: Single-energy material decomposition using X-ray path length estimation.
abstract: OBJECTIVE
  Clinical computed tomographies (CTs) can typically use only a single energy at a time. The main purpose of the present paper was to study whether the calculated x-ray path lengths can help replace one of the 2 dual-energy measurements by 2-material decomposition.
  
  
  METHODS
  The proposed single-energy material decomposition method (SEMD) is based on the evaluation of a single CT scan. The SEMD combines postreconstruction and prereconstruction algorithms for the determination of x-ray path length and material decomposition, respectively.
  
  
  RESULTS
  The simulation results of the proposed and dual-energy methods were compared using pregenerated look-up tables. The results show that SEMD is more sensitive to CT signal errors at higher tube voltages. The dual-energy method is generally less sensitive to CT signal bias but more sensitive to the noise.
  
  
  CONCLUSIONS
  In the case of inferior signal errors, the proposed method gives the same results as the dual-energy variant. Although the x-ray path length estimation method with SEMD is more complex, the dose is considerably lower.
authors.affiliation: Department of Optics and Quantum Electronics, University of Szeged, Szeged, Hungary. kisjbenedek@gmail.com
authors.forename: Benedek Janos
authors.initials: BJ
authors.lastname: Kis
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Sarnyai
authors.forename: Róbert
authors.initials: R
authors.lastname: Kákonyi
authors.forename: Miklós
authors.initials: M
authors.lastname: Erdélyi
authors.forename: Gábor
authors.initials: G
authors.lastname: Szabó
mesh_terms: D000465:Algorithms; D055592:Biophysical Phenomena; D019047:Phantoms, Imaging; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D012815:Signal Processing, Computer-Assisted; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014965:X-Rays