title: Low-tube-voltage selection for non-contrast-enhanced CT: Comparison of the radiation dose in pediatric and adult phantoms.
abstract: OBJECTIVE
  We used pediatric and adult anthropomorphic phantoms to compare the radiation dose of low- and standard tube voltage chest and abdominal non-contrast-enhanced computed tomography (CT) scans. We also discuss the optimal low tube voltage for non-contrast-enhanced CT.
  
  
  METHODS
  Using a female adult- and three differently-sized pediatric anthropomorphic phantoms we acquired chest and abdominal non-contrast-enhanced scans on a 320-multidetector CT volume scanner. The tube voltage was set at 80-, 100-, and 120 kVp. The tube current was automatically assigned on the CT scanner in response to the set image noise level. On each phantom and at each tube voltage we measured the surface and center dose using high-sensitivity metal-oxide-semiconductor field-effect transistor detectors.
  
  
  RESULTS
  The mean surface dose of chest and abdominal CT scans in 5-year olds was 4.4 and 5.3 mGy at 80 kVp, 4.5 and 5.4 mGy at 100 kV, and 4.0 and 5.0 mGy at 120 kVp, respectively. These values were similar in our 3-pediatric phantoms (p > 0.05). The mean surface dose in the adult phantom increased from 14.7 to 19.4 mGy for chest- and from 18.7 to 24.8 mGy for abdominal CT as the tube voltage decreased from 120 to 80 kVp (p < 0.01).
  
  
  CONCLUSIONS
  Compared to adults, the surface and center dose for pediatric patients is almost the same despite a decrease in the tube voltage and the low tube voltage technique can be used for non-contrast-enhanced chest- and abdominal scanning.
authors.affiliation: Department of Radiology, Kumamoto University Hospital, Kumamoto, Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Shimonobo
authors.affiliation: Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan. Electronic address: funama@kumamoto-u.ac.jp.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Funama
authors.affiliation: Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Utsunomiya
authors.affiliation: Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakaura
authors.affiliation: Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: Seitaro
authors.initials: S
authors.lastname: Oda
authors.affiliation: Department of Diagnostic Radiology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
authors.forename: Masao
authors.initials: M
authors.lastname: Kiguchi
authors.affiliation: Department of Diagnostic Radiology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Masuda
authors.affiliation: Department of Radiology, Kumamoto University Hospital, Kumamoto, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Sakabe
authors.affiliation: Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Yamashita
authors.affiliation: Department of Diagnostic Radiology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Awai
mesh_terms: D000328:Adult; D000465:Algorithms; D000886:Anthropometry; D001835:Body Weight; D002648:Child; D002675:Child, Preschool; D003287:Contrast Media / Q000737:chemistry*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D061330:Multidetector Computed Tomography / Q000379:methods*; D010372:Pediatrics; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D011860:Radiography, Abdominal / Q000379:methods; D013902:Radiography, Thoracic / Q000379:methods
chemical_list: D003287:Contrast Media
keywords: Low tube voltage; Non-contrast enhanced CT; Radiation dose; Small pediatric patients