Non-invasive assessment of small airway obstruction in asthma

摘要: Small airway inflammation and remodelling occurs in asthma may underpin disease persistence, since conventional inhaled treatments do not penetrate to the small compartment. There is an important unmet need for reliable non-invasive methods measure obstruction. This thesis describes development validation of such methods, with a particular focus on multiple breath inert gas washout (MBW) technique. In vitro sulphur hexafluoride wash-in technique performing MBW demonstrated that method yields accurate repeatable results. We developed novel analysing curves, showed parameters derived are repeatable, capture full information content curve, be superior standard distinguishing between subphenotypes diseases. impulse oscillometry (IOS) were found within-visit, but IOS displayed greater stability over time. independent predictors symptoms, quality life exacerbation frequency, suggesting add value spirometry assessment patients asthma. The response biomarkers intervention was assessed within clinical trial antieosinophilic agent. Significant treatment effects observed respect spirometric airflow obstruction air trapping, as well number parameters. structural correlates ventilation heterogeneity examined using hyperpolarised helium magnetic resonance quantitative computed tomography. evidence abnormality pulmonary acinus causing subtle alterations diffusion this Future studies should seek further understand basis through computational modelling coupling physiological measurements functional imaging. Longitudinal also required assess long-term significance biomarkers.