title: Material Decomposition in Dual-Energy Computed Tomography Separates High-Z Elements From Iodine, Identifying Potential Contrast Media Tailored for Dual Contrast Medium Examinations.
abstract: OBJECTIVE
  The aim of this study was to determine the potential of different high-Z elements to act as contrast media (CMs) alongside iodine (I) in dual-CM, dual-energy (DE) computed tomography examinations.
  
  
  METHODS
  Gadolinium (Gd), tantalum (Ta), wolfram (W), gold (Au), and bismuth (Bi) in addition to I were examined at all available kilovolt settings in a DE computed tomography scanner. Dual-energy ratios were calculated by dividing attenuation at low kilovolt by attenuation at high kilovolt. Dual-energy data sets were loaded into material decomposition software to evaluate separation of the elements from I.
  
  
  RESULTS
  The DE ratios of Ta, W, and Au ranged between 0.9 and 1.2, being considerably lower than I at 1.9 to 2.6. These elements were completely separated from I using material decomposition. Gadolinium and Bi were more similar to I at 1.4 to 1.9. However, separation was nearly complete for Bi and suboptimal for Gd.
  
  
  CONCLUSIONS
  Tantalum, W, and Au are ideal candidates for dual-CM examinations, whereas Bi is a slightly weaker candidate.
authors: From the Departments of *Radiology, and †Clinical Sciences, Medical Radiation Physics, Lund University, Skåne University Hospital, Malmö, Sweden.
authors: Tobias
authors: T
authors: Fält
authors: Marcus
authors: M
authors: Söderberg
authors: Johan
authors: J
authors: Wassélius
authors: Peter
authors: P
authors: Leander
mesh_terms: D001729:Bismuth / Q000493:pharmacokinetics; D003287:Contrast Media / Q000493:pharmacokinetics*; D005682:Gadolinium / Q000493:pharmacokinetics; D006046:Gold / Q000493:pharmacokinetics; D007089:Image Enhancement; D007455:Iodine / Q000493:pharmacokinetics*; D019216:Metals, Heavy / Q000493:pharmacokinetics*; D019047:Phantoms, Imaging; D011857:Radiographic Image Interpretation, Computer-Assisted; D013635:Tantalum / Q000493:pharmacokinetics; D014057:Tomography, X-Ray Computed; D014414:Tungsten / Q000493:pharmacokinetics
chemical_list: D003287:Contrast Media; D019216:Metals, Heavy; D013635:Tantalum; D006046:Gold; D007455:Iodine; D005682:Gadolinium; D001729:Bismuth; D014414:Tungsten