title: Current methods to diagnose small airway disease in patients with COPD.
abstract: The small airways are characterized by an internal diameter < 2 mm and absence of cartilage. Approximately 10-25% of total airway resistance in healthy lungs is due to the small airways, with their contribution to total airway resistance increasing substantially in chronic obstructive pulmonary disease (COPD). As the small airways are located in the lung periphery, they are not easily evaluable, which can potentially interfere with the diagnosis (especially at early stages), monitoring, detection of responses to clinical interventions, and prognostic evaluation in COPD. Here, we will discuss the currently available methods in clinical practice to evaluate small airway disease in COPD, focusing on the concept, advantages, and disadvantages of each method.
authors.affiliation: a Centre for Heart Lung Innovation, St. Paul´s Hospital, & Department of Medicine , University of British Columbia , Vancouver , British Columbia , Canada.
authors.forename: Fernando Sergio
authors.initials: FS
authors.lastname: Leitão Filho
authors.affiliation: a Centre for Heart Lung Innovation, St. Paul´s Hospital, & Department of Medicine , University of British Columbia , Vancouver , British Columbia , Canada.
authors.forename: Hao
authors.initials: H
authors.lastname: Hang Chen
authors.affiliation: a Centre for Heart Lung Innovation, St. Paul´s Hospital, & Department of Medicine , University of British Columbia , Vancouver , British Columbia , Canada.
authors.forename: David A
authors.initials: DA
authors.lastname: Ngan
authors.affiliation: a Centre for Heart Lung Innovation, St. Paul´s Hospital, & Department of Medicine , University of British Columbia , Vancouver , British Columbia , Canada.
authors.forename: Anthony
authors.initials: A
authors.lastname: Tam
authors.affiliation: a Centre for Heart Lung Innovation, St. Paul´s Hospital, & Department of Medicine , University of British Columbia , Vancouver , British Columbia , Canada.
authors.forename: Miranda
authors.initials: M
authors.lastname: Kirby
authors.affiliation: a Centre for Heart Lung Innovation, St. Paul´s Hospital, & Department of Medicine , University of British Columbia , Vancouver , British Columbia , Canada.
authors.forename: Don D
authors.initials: DD
authors.lastname: Sin
keywords: COPD; body plethysmography; computed tomography; small airways; spirometry; washout tests