Hernandez‐Rojas, Daniel

Background: Severe excessive dynamic airway collapse (EDAC) is defined as airway narrowing due to posterior wall protrusion into the airway lumen, >90%. We aimed to establish an overall severity score to assess severe EDAC and the need for subsequent intervention. Methods: A retrospective study of patients who underwent dynamic bronchoscopy for evaluation of expiratory central airway collapse between January 2019 and July 2021. A numerical value was given to each tracheobronchial segmental collapse: 0 points (<70%), 1 point (70% to 79%), 2 points (80% to 89%), and 3 points (>90%) to be added for an overall EDAC severity score per patient. We compared the score among patients who underwent stent trials (severe EDAC) and those who did not. Based on the receiver operating characteristics curve, a cutoff total score to predict severe EDAC was calculated. Results: One hundred fifty-eight patients were included. Patients were divided into severe (n = 60) and nonsevere (n = 98) EDAC. A cutoff of 9 as the total score had a sensitivity of 94% and a specificity of 74% to predict severe EDAC, based on an area under the curve 0.888 (95% CI: 0.84, 0.93; P < 0.001). Conclusion: Our EDAC Severity Scoring System was able to discern between severe and nonsevere EDAC by an overall score cutoff of 9, with high sensitivity and specificity for predicting severe disease and the need for further intervention, in our institution.

AbstractExpiratory central airway collapse (ECAC) is a pathology gaining recognition in the medical community due to its unspecific symptoms and diagnostic challenges. Its current gold standard for diagnosis, dynamic bronchoscopy, is invasive. Current non‐invasive techniques such as computed tomography (CT) protocols have shown limited reproducibility. We present a case of a 77‐year‐old man with suspected ECAC who underwent evaluation with two different expiratory CT protocols. The initial standard end‐expiratory CT could not detect airway collapsibility. However, dynamic bronchoscopy detected severe ECAC. Afterwards, we implemented a novel CT protocol, called dynamic forced expiratory CT (cinematic), comprising detailed, consecutive helical imaging of the central airway throughout the entire respiratory cycle, detecting severe ECAC, as proven by the earlier dynamic bronchoscopy. We hypothesize this may reduce the risks and need for performing multiple invasive procedures such as dynamic bronchoscopy. Extensive studies are required to evaluate the feasibility of its implementation for diagnosing ECAC.