title: Image quality and radiation dose of brain computed tomography in children: effects of decreasing tube voltage from 120 kVp to 80 kVp.
abstract: BACKGROUND
  Computed tomography (CT) has generated public concern associated with radiation exposure, especially for children. Lowering the tube voltage is one strategy to reduce radiation dose.
  
  
  OBJECTIVE
  To assess the image quality and radiation dose of non-enhanced brain CT scans acquired at 80 kilo-voltage peak (kVp) compared to those at 120 kVp in children.
  
  
  METHODS
  Thirty children who had undergone both 80- and 120-kVp non-enhanced brain CT were enrolled. For quantitative analysis, the mean attenuation of white and gray matter, attenuation difference, noise, signal-to-noise ratio, contrast-to-noise ratio and posterior fossa artifact index were measured. For qualitative analysis, noise, gray-white matter differentiation, artifact and overall image quality were scored. Radiation doses were evaluated by CT dose index, dose-length product and effective dose.
  
  
  RESULTS
  The mean attenuations of gray and white matter and contrast-to-noise ratio were significantly increased at 80 kVp, while parameters related to image noise, i.e. noise, signal-to-noise ratio and posterior fossa artifact index were higher at 80 kVp than at 120 kVp. In qualitative analysis, 80-kVp images showed improved gray-white differentiation but more artifacts compared to 120-kVp images. Subjective image noise and overall image quality scores were similar between the two scans. Radiation dose parameters were significantly lower at 80 kVp than at 120 kVp.
  
  
  CONCLUSIONS
  In pediatric non-enhanced brain CT scans, a decrease in tube voltage from 120 kVp to 80 kVp resulted in improved gray-white matter contrast, comparable image quality and decreased radiation dose.
authors.affiliation: Department of Radiology, Graduate School, Kyung Hee University Hospital, Seoul, South Korea.
authors.forename: Ji Eun
authors.initials: JE
authors.lastname: Park
authors.affiliation: Department of Radiology, Seoul National University Hospital, 101, Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea. iater@snu.ac.kr.|Department of Radiology, Seoul National University College of Medicine, Seoul, South Korea. iater@snu.ac.kr.
authors.forename: Young Hun
authors.identifier: http://orcid.org/0000-0002-1842-9062
authors.initials: YH
authors.lastname: Choi
authors.affiliation: Department of Radiology, Seoul National University Hospital, 101, Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea.|Department of Radiology, Seoul National University College of Medicine, Seoul, South Korea.|Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, South Korea.
authors.forename: Jung-Eun
authors.initials: JE
authors.lastname: Cheon
authors.affiliation: Department of Radiology, Seoul National University Hospital, 101, Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea.|Department of Radiology, Seoul National University College of Medicine, Seoul, South Korea.|Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, South Korea.
authors.forename: Woo Sun
authors.initials: WS
authors.lastname: Kim
authors.affiliation: Department of Radiology, Seoul National University Hospital, 101, Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea.|Department of Radiology, Seoul National University College of Medicine, Seoul, South Korea.|Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, South Korea.
authors.forename: In-One
authors.initials: IO
authors.lastname: Kim
authors.affiliation: Department of Radiology, Seoul National University Hospital, 101, Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea.
authors.forename: Hyun Suk
authors.initials: HS
authors.lastname: Cho
authors.affiliation: Department of Radiology, Seoul National University Hospital, 101, Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea.
authors.forename: Young Jin
authors.initials: YJ
authors.lastname: Ryu
authors.affiliation: Department of Radiology, Seoul National University Hospital, 101, Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea.
authors.forename: Yu Jin
authors.initials: YJ
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D001921:Brain / Q000528:radiation effects*; D001927:Brain Diseases / Q000000981:diagnostic imaging*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011829:Radiation Dosage; D011835:Radiation Protection / Q000379:methods*; D059629:Signal-To-Noise Ratio; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Brain; Children; Computed tomography; Dose reduction; Ionizing radiation; Tube voltage