Pediatric Radiology

, Volume 36, Issue 1, pp 50–53 | Cite as

Dose reduction for CT in children with cystic fibrosis: is it feasible to reduce the number of images per scan?

  • Pim A. de Jong
  • Yasutaka Nakano
  • Maarten H. Lequin
  • Harm A. W. M. Tiddens
Original Article



Reducing the dose for each CT scan is important for children with cystic fibrosis (CF).


To determine whether the number of CT images and therefore the dose per CT scan could be reduced without any significant loss of information in children with CF.

Materials and methods

A cohort of children with CF was followed with biennial surveillance CT scans, obtained in inspiration after a voluntary breath-hold as 1-mm thick images at 10-mm intervals from lung apex to base. A random set of 20 baseline CT scans and 10 follow-up CT scans were blinded. Sets of every image (10-mm intervals), every second image (20-mm intervals), every third image (30-mm intervals) and a selection of three and five images were scored randomly using a published CT scoring system by one experienced observer.


The 20 subjects were 10 years of age with a range of 3.7–17.6 years at baseline. Fewer CT images resulted in a significantly lower (less abnormal) CT score and the number of patients positive for abnormalities decreased subsequently. At intervals greater than 20 mm no significant change in CT score over 2 years could be detected, while the CT scores at 10-mm (P=0.02) and 20-mm (P=0.02) intervals worsened significantly.


A reduction in the number of inspiratory CT images by increasing the interval between images to greater than 10 mm is not a valid option for radiation dose reduction in children with CF.


Lungs Cystic fibrosis CT Children 


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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Pim A. de Jong
    • 1
  • Yasutaka Nakano
    • 2
  • Maarten H. Lequin
    • 3
  • Harm A. W. M. Tiddens
    • 1
  1. 1.Department of Paediatric Pulmonology and Allergology, Erasmus MCSophia Children's HospitalRotterdamThe Netherlands
  2. 2.Department of Respiratory MedicineShiga University of Medical ScienceOtsuJapan
  3. 3.Department of Paediatric Radiology, Erasmus MCSophia Children's HospitalRotterdamThe Netherlands

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