title: Evaluation of the impact of organ-specific dose reduction on image quality in pediatric chest computed tomography.
abstract: BACKGROUND
  Organ-specific dose reduction significantly reduces the radiation exposure of radiosensitive organs.
  
  
  OBJECTIVE
  The purpose of this study was to assess the impact of a novel organ-specific dose reduction algorithm on image quality of pediatric chest CT.
  
  
  METHODS
  We included 28 children (mean age 10.9 ± 4.8 years, range 3-18 years) who had contrast-enhanced chest CT on a 128-row scanner. CT was performed at 100 kV using automated tube current modulation and a novel organ-specific dose-reduction algorithm (XCare™; Siemens, Forchheim, Germany). Seven children had a previous chest CT performed on a 64-row scanner at 100 kV without organ-specific dose reduction. Subjective image quality was assessed using a five-point scale (1-not diagnostic; 5-excellent). Contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) were assessed in the descending aorta.
  
  
  RESULTS
  Overall mean subjective image quality was 4.1 ± 0.6. In the subgroup of the seven children examined both with and without organ-specific dose reduction, subjective image quality was comparable (score 4.4 ± 0.5 with organ-specific dose reduction vs. 4.4 ± 0.7 without it; P > 0.05). There was no significant difference in mean signal-to-noise ratio and contrast-to-noise ratio with organ-specific dose reduction (38.3 ± 10.1 and 28.5 ± 8.7, respectively) and without the reduction (35.5 ± 8.5 and 26.5 ± 7.8, respectively) (P > 0.05). Volume computed tomography dose index (CTDIvol) and size-specific dose estimates did not differ significantly between acquisitions with the organ-specific dose reduction (1.7 ± 0.8 mGy) and without the reduction (1.7 ± 0.8 mGy) (P > 0.05).
  
  
  CONCLUSIONS
  Organ-specific dose reduction does not have an impact on image quality of pediatric chest CT and can therefore be used in clinical practice to reduce radiation dose of radiosensitive organs such as breast and thyroid gland.
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Dusseldorf, Medical Faculty, D-40225, Dusseldorf, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Boos
authors.forename: Patric
authors.initials: P
authors.lastname: Kröpil
authors.forename: Dirk
authors.initials: D
authors.lastname: Klee
authors.forename: Philipp
authors.initials: P
authors.lastname: Heusch
authors.forename: Lars
authors.initials: L
authors.lastname: Schimmöller
authors.forename: Jörg
authors.initials: J
authors.lastname: Schaper
authors.forename: Gerald
authors.initials: G
authors.lastname: Antoch
authors.forename: Rotem S
authors.initials: RS
authors.lastname: Lanzman
mesh_terms: D000293:Adolescent; D000465:Algorithms; D002648:Child; D002675:Child, Preschool; D003287:Contrast Media; D005260:Female; D006801:Humans; D008297:Male; D011829:Radiation Dosage; D011835:Radiation Protection / Q000379:methods*; D013902:Radiography, Thoracic / Q000379:methods*; D012189:Retrospective Studies; D059629:Signal-To-Noise Ratio; D013909:Thorax / Q000528:radiation effects; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media