Objectives: Dynamic flexible bronchoscopy is the "gold standard" for assessing changes in airway luminal size associated with tracheobronchomalacia, but the procedure has not been adequately validated. The present study was designed to test the validity of diagnosing tracheobronchomalacia by dynamic flexible bronchoscopy through assessing inter- and intraobserver agreements in estimating degree of central airway collapse associated with tracheobronchomalacia.
Methods: This prospective observational pilot study enrolled consecutive patients with suspected tracheobronchomalacia scheduled for dynamic flexible bronchoscopy. Images of the airway lumen were obtained at five different sites in the tracheobronchial tree during forced inspiration and expiration and were evaluated by 23 pulmonologists (not involved in the care of study patients) with different levels of training and experience at baseline (interobserver agreement) and 8 days later (intraobserver agreement). The degree of airway collapse was visually estimated by each examiner and expressed as a percentage of narrowing. A multirater generalized kappa-type statistical method was used to calculate the correlation coefficients and to assess reliability of the measurements obtained during dynamic flexible bronchoscopy.
Measurements and main results: Between September 1 and 30, 2009, 10 patients (median age, 65 yr) underwent dynamic flexible bronchoscopy. The correlation coefficients for inter- and intraobserver agreement were favorable and ranged for the five airway sites from 0.68 to 0.92 and from 0.80 to 0.96, respectively.
Conclusions: The favorable inter- and intraobserver agreements among 23 pulmonologists using dynamic flexible bronchoscopy to estimate the degree of dynamic central airway collapse provide additional evidence that dynamic flexible bronchoscopy is a reliable diagnostic tool for tracheobronchomalacia.
Keywords: airway obstruction; bronchomalacia; bronchoscopy; excessive dynamic airway collapse; tracheomalacia.