PhD defence W.B. (Wytse) van den Bosch

Brief summary: 

This dissertation explores the structure and function of small airways in children with severe asthma, contributing to the understanding of (severe) asthma pathophysiology. Part of the research involved analysing chest computed tomography (CT) scans using both manual and artificial intelligence (AI) techniques. The findings reveal extensive airway abnormalities, including a high prevalence of bronchiectasis and bronchial wall thickening, especially in the smaller sized airways. Small airway disease (SAD) was detected in all chest CTs. AI showed to be very sensitive in measuring bronchial dimensions and detecting bronchial abnormalities. The high frequency of bronchial abnormalities highlights the need for low-dose chest CT scans to be included in severe asthma assessments.

The dissertation also evaluated magnetic resonance imaging (MRI) techniques in detecting low-intensity regions (LIR) in children with cystic fibrosis, asthma, and healthy subjects. The results show that spirometer-controlled MRI improves LIR detection and provides accurate lung volume measurements, offering a radiation-free alternative to CT scans. 
Besides, detecting and monitoring of SAD this dissertation also evaluated small airways aerosol deposition and targeted treatment. Children with SAD experience higher aerosol deposition in the larger central airways, suggesting chronic under-dosing in the smaller peripheral airways. An investigation into smart nebulizers for small airway treatment showed promising results, with significant reductions in asthma exacerbations and better disease management. 

Finally, the thesis also discusses the ethical challenges posed by the acquisition of Vectura Group by tobacco company Philip Morris International, offering guidelines for researchers facing similar dilemmas.