Computed tomography in children with cystic fibrosis: a new way to reduce radiation dose.

Abstract

To determine whether the monitoring of respiratory disease progression in children with cystic fibrosis (CF) can be made using six pre-selected computed tomography (CT) cuts in lieu of the conventional full study. Forty one lung CT scans from 21 paediatric patients with CF were analysed. The Bhalla and Nathanson scores of the total lung CT and the six pre-selected CT cuts were compared. The Bhalla mean score of the total lung CT evaluated by two radiologists was 5.62. It was 5.36 when just the six pre-selected sections were evaluated. The difference between means was not statistically significant. The Nathanson mean score of the total lung CT evaluated by both radiologists was 66.11; it was 66.51 when just the six pre-selected sections were evaluated. The difference between means was not statistically significant. The mean total radiation dose from a single whole lung CT scan was 716.22 mGy.cm. A dose of 250.66 mGy.cm was estimated if only six sections were used, with a reduction in radiation of about 65%. It is possible to obtain the same radiological information from six pre-selected CT cuts as it is from a full pulmonary CT scan, thereby markedly reducing radiation exposure for children who will require repeat investigations in the future.