title: Evaluation of chest CT scan in low-weight children with ultralow tube voltage (70 kVp) combined with Flash scan technique.
abstract: OBJECTIVE
  To assess radiation dose and image quality of chest CT examinations in low-weight children acquired at ultralow tube voltage (70 kVp) combined with Flash scan technique.
  
  
  METHODS
  30 consecutive paediatric patients (weight <20 kg) required non-contrast chest CT at 70 kVp with Flash scan mode (Group A). 30 patients for paediatric standard 80-kVp protocols with conventional spiral mode (Group B) were selected from the picture archiving and communication system. For each examination, the volume CT dose index (CTDIvol) and dose-length product (DLP), and the effective dose (adapted as 16-cm phantom) (ED16cm) were estimated. The image noise, signal-to-noise ratio (SNR), overall subjective image quality and respiratory motion artefacts were evaluated.
  
  
  RESULTS
  For radiation dose, CTDIvol (mGy), DLP (mGy cm) and ED16cm (mSv) of Group A were significantly lower than those of Group B [CTDIvol: 0.48 ± 0.003 mGy (Group A) vs 0.80 ± 0.005 mGy (Group B); p<0.001 DLP: 10.23 ± 1.35 mGy cm (Group A) vs 15.6 ± 2.02 mGy cm (Group B); p<0.001 ED16cm: 0.61 ± 0.91 mSv (Group A) vs 0.89 ± 0.13 mSv (Group B); p<0.001]. The mean image noise with Group A increased 28.5% (p = 0.002), and the mean SNR decreased 14.8% compared with Group B (p = 0.193). There was no statistical difference in overall subjective image quality grades, and Group A had significantly lower respiratory motion artefact grades than Group B (p < 0.001).
  
  
  CONCLUSIONS
  Ultralow tube voltage (70 kVp) combined with the Flash scan technique of the chest can obtain images with clinically acceptable image noise and minimum respiratory motion artefacts in low-weight children, whilst reducing radiation dose significantly.
  
  
  CONCLUSIONS
  The feasibility of chest CT scan in low-weight children with ultralow tube voltage (70 kVp) combined with Flash scan technique has firstly been evaluated in our study.
authors.affiliation: Department of Medical Imaging, The First People's Hospital of Wujiang, Wujiang, China.
authors.forename: Jiang W
authors.initials: JW
authors.lastname: Shi
authors.affiliation: Department of Medical Imaging, The First People's Hospital of Wujiang, Wujiang, China.
authors.forename: Dong F
authors.initials: DF
authors.lastname: Xu
authors.affiliation: Department of Medical Imaging, The First People's Hospital of Wujiang, Wujiang, China.
authors.forename: Hong Z
authors.initials: HZ
authors.lastname: Dai
authors.affiliation: Department of Medical Imaging, The First People's Hospital of Wujiang, Wujiang, China.
authors.forename: Li
authors.initials: L
authors.lastname: Shen
authors.affiliation: Department of Medical Imaging, The First People's Hospital of Wujiang, Wujiang, China.
authors.forename: Yi D
authors.initials: YD
authors.lastname: Ji
mesh_terms: D002675:Child, Preschool; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D011446:Prospective Studies; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D013902:Radiography, Thoracic; D059629:Signal-To-Noise Ratio; D013851:Thinness / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed