Advances in bronchoscopic lung volume reduction:Improved patient selection and assessment of treatment response

Bronchoscopic lung volume reduction is a relatively new treatment for patients with severe COPD, a chronic and progressive lung disease. The aim of this treatment is to decrease the increased residual volume, in order to improve disease symptoms and quality of life. Not every patient with COPD is eligible to undergo this treatment, and treatment outcomes vary between patients. The aim of this thesis was to improve patient selection for bronchoscopic lung volume reduction, and to improve the identification of patients who achieved a relevant treatment effect.Only one out of five patients that are referred, are actually eligible for treatment. This finding highlights the importance of the development of new treatments for the large group of patients that are currently not eligible for bronchoscopic treatments. In one of the studies in this thesis, we have introduced an innovative approach to measure oxygen uptake capacity of individual lobes of the lung, which can prove a valuable contribution to the identification of the least functional lobe, and thus best treatment target. Two other studies demonstrated that the measurement of interlobar collateral ventilation, an essential measurement before treatment with endobronchial valves, is easier and faster to perform under general anesthesia than under conscious sedation. This finding supports the clinical practice to perform both this measurement as well as the treatment in one session under general anesthesia. Finally, we have introduced a new threshold for a clinically relevant treatment effect for two important outcome parameters after treatment: lung volume reduction measured on a CT scan and a quality of life questionnaire