title: Selection of optimal tube potential settings for dual-energy CT virtual mono-energetic imaging of iodine in the abdomen.
abstract: To determine the appropriate tube potential settings for dual-source, dual-energy data acquisition across a range of phantom sizes, and to determine the optimal photon energies for virtual mono-energetic imaging.
  
  
  
  Water phantoms (15-50-cm wide) containing an iodine test object were scanned on a third-generation dual-source CT scanner using all available tube potential pairs. Virtual mono-energetic images at 40, 50, 60, and 70 keV were produced using Mono-energetic Plus. To determine the practical operating parameters for the evaluated CT system, data exclusions were made based on water CT number accuracy, artifacts, and using a noise constraint. Image quality metrics were measured and compared.
  
  
  
  Excluded tube potential pairs were identified; these were generally at low tube potentials for the low-energy beam and low photon energies. For non-excluded conditions, the highest CNR was obtained using the 70/150Sn setting in phantoms ≤35 cm at 40 keV.
  
  
  
  70/150Sn provided optimal iodine CNR below 40 cm lateral phantom width at 40 keV, while 90/150Sn allowed acceptable image quality in phantoms >40-cm wide at or above 60 keV.
authors.affiliation: Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
authors.forename: Gregory
authors.initials: G
authors.lastname: Michalak
authors.affiliation: Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
authors.forename: Joshua
authors.initials: J
authors.lastname: Grimes
authors.affiliation: Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
authors.forename: Joel
authors.initials: J
authors.lastname: Fletcher
authors.affiliation: Siemens Healthcare, 40 Liberty Blvd, Malvern, PA, 19355, USA.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Halaweish
authors.affiliation: Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
authors.forename: Lifeng
authors.initials: L
authors.lastname: Yu
authors.affiliation: Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
authors.forename: Shuai
authors.initials: S
authors.lastname: Leng
authors.affiliation: Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA. mccollough.cynthia@mayo.edu.
authors.forename: Cynthia
authors.initials: C
authors.lastname: McCollough
mesh_terms: D006801:Humans; D007455:Iodine; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D011860:Radiography, Abdominal / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D007455:Iodine
keywords: Dual-energy CT; Virtual mono-chromatic; Virtual mono-energetic