Bronchoscopic Measurement of Collateral Ventilation: State of the Art.

Endoscopic lung volume reduction procedure with valves is a well-studied treatment option for advanced lung emphysema to target lung hyperinflation in carefully selected patients with COPD. Before valve implantation, collateral ventilation (CV) of the target lobe needs to be assessed to obtain an optimal treatment effect. The analysis of CV according to current standards occurs via an in vivo assessment with the Chartis®system (PulmonX Inc., Redwood City, CA, USA) and a computed tomography (CT) scan of the thorax with interlobar fissure analysis. The focus of this review is to provide detailed information about the Chartis®procedure and interpretation of Chartis® phenotypes. As a main tool in the assessment of CV and being a safe procedure, the Chartis® assessment should be performed by default to confirm interlobar fissure analysis in most emphysema patients. Based on the obtained results, lung volume reduction therapy options should be discussed in an interdisciplinary emphysema conference.