title: Head CT: Image quality improvement with ASIR-V using a reduced radiation dose protocol for children.
abstract: OBJECTIVE
  To investigate the quality of images reconstructed with adaptive statistical iterative reconstruction V (ASIR-V), using pediatric head CT protocols.
  
  
  METHODS
  A phantom was scanned at decreasing 20% mA intervals using our standard pediatric head CT protocols. Each study was then reconstructed at 10% ASIR-V intervals. After the phantom study, we reduced mA by 10% in the protocol for <3-year-old patients and applied 30% ASIR-V and by 30% in the protocol for 3- to 15-year-old patients and applied 40% ASIR-V.
  
  
  RESULTS
  Increasing the percentage of ASIR-V resulted in lower noise and higher contrast-to-noise ratio (CNR) and preserved spatial resolution in the phantom study. Compared to a conventional-protocol, reduced-dose protocol with ASIR-V achieved 12.8% to 34.0% of dose reduction and showed images of lower noise (9.22 vs. 10.73, P = 0.043) and higher CNR in different levels (centrum semiovale, 2.14 vs. 1.52, P = 0.003; basal ganglia, 1.46 vs. 1.07, P = 0.001; and cerebellum, 2.18 vs. 1.33, P < 0.001). Qualitative analysis showed higher gray-white matter differentiation and sharpness and preserved overall diagnostic quality in the images with ASIR-V.
  
  
  CONCLUSIONS
  Use of ASIR-V allowed a 12.8% to 34.0% dose reduction in each age group with potential to improve image quality.
  
  
  CONCLUSIONS
  • It is possible to reduce radiation dose and improve image quality with ASIR-V. • We improved noise and CNR and decreased radiation dose. • Sharpness improved with ASIR-V. • Total radiation dose was decreased by 12.8% to 34.0%.
authors.affiliation: Department of Radiology, Ajou University School of Medicine, Ajou University Medical Center, 164 World Cup-ro, Yeongtong-gu, Suwon, Korea, 443-380.
authors.forename: Hyun Gi
authors.initials: HG
authors.lastname: Kim
authors.affiliation: Department of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, Korea, 120-752.
authors.forename: Ho-Joon
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: Department of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, Korea, 120-752.
authors.forename: Seung-Koo
authors.initials: SK
authors.lastname: Lee
authors.affiliation: Office of Biostatistics, Department of Humanities and Social Medicine, Ajou University School of Medicine, 164 World Cup-ro, Yeongtong-gu, Suwon, Korea, 443-380.
authors.forename: Hyun Ji
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, Korea, 120-752. mjkim@yuhs.ac.
authors.forename: Myung-Joon
authors.initials: MJ
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D001921:Brain / Q000000981:diagnostic imaging*; D002648:Child; D002675:Child, Preschool; D002985:Clinical Protocols; D005260:Female; D006801:Humans; D008297:Male; D019047:Phantoms, Imaging; D058996:Quality Improvement; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods* / Q000592:standards
keywords: Brain; Computer-assisted methods; Pediatric; Radiation dosage; Radiation protection methods