title: Half-dose abdominal CT with sinogram-affirmed iterative reconstruction technique in children - comparison with full-dose CT with filtered back projection.
abstract: BACKGROUND
  Iterative reconstruction can be helpful to reduce radiation dose while maintaining image quality. However, this technique has not been fully evaluated in children during abdominal CT.
  
  
  OBJECTIVE
  To compare objective and subjective image quality between half-dose images reconstructed with iterative reconstruction at iteration strength levels 1 to 5 (half-S1 to half-S5 studies) and full-dose images reconstructed with filtered back projection (full studies) in pediatric abdominal CT.
  
  
  METHODS
  Twenty-one children (M:F = 13:8; mean age 8.2 ± 5.7 years) underwent dual-source abdominal CT (mean effective dose 4.8 ± 2.1 mSv). The objective image quality was evaluated as noise. Subjective image quality analysis was performed comparing each half study to the full study for noise, sharpness, artifact and diagnostic acceptability.
  
  
  RESULTS
  Both objective and subjective image noise decreased with increasing iteration strength. Half-S4 and -S5 studies showed objective image noise similar to or lower than that of full studies. The half-S2 and -S3 studies produced the greatest sharpness and the half-S5 studies were the worst from a blocky appearance. Full and half studies did not differ in artifacts. Half-S3 studies showed the best diagnostic acceptability.
  
  
  CONCLUSIONS
  Half-S4 and -S5 studies objectively and half-S3 studies subjectively showed comparable image quality to full studies in pediatric abdominal CT.
authors.affiliation: Department of Radiology and Research Institute of Radiological Science, Severance Children's Hospital, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, 120-752, Seoul, South Korea.
authors.forename: Minwook
authors.initials: M
authors.lastname: Lee
authors.forename: Myung-Joon
authors.initials: MJ
authors.lastname: Kim
authors.forename: Kyung Hwa
authors.initials: KH
authors.lastname: Han
authors.forename: Mi-Jung
authors.initials: MJ
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D016477:Artifacts; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D011860:Radiography, Abdominal; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*