Advanced Pediatric Chest Computed Tomography : Safe and standardized protocols and sensitive image analysis of cystic fibrosis lung disease

Children with cystic fibrosis (CF) routinely receive computed tomography (CT) scans in many centers to diagnose and monitor their lung disease. This thesis is divided in three parts.
Part one focuses on radiation safety and standardization of chest CT in the pediatric CF population. Accumulative radiation exposure has been estimated based on current radiation levels and put into perspective. The standardization of pediatric chest CT was performed among 16 CF centers where considerable differences were found in CT protocols, image quality and radiation doses. However this study showed that with adjustment for spatial resolution and radiation dose, standardization of chest CT is feasible in an international multicenter cohort.
In part two novel image analysis techniques related to chest CT of children and adolescents with CF were assessed. The airway and artery structures in the lungs were analyzed quantitatively to evaluate structural lung changes like bronchiectasis, including airway tapering and airway wall thickening. The diagnosis of bronchiectasis in children was found to be more sensitive with the outer airway diameter instead of the inner airway diameter and is confirmed to be influenced by lung volume. Additionally structural airway changes were found to be more prominent in the peripheral airways suggesting that airway changes might be first detectable in the smaller airways.
Part three consists of reference values of the central and main airway structures on chest CT for children and adolescents.