Dynamic Airway Collapse and Tracheobronchial Disorders

Dynamic airway collapse encompasses a spectrum of conditions in which the trachea and main bronchi lose structural rigidity during respiration, leading to symptomatic airway obstruction. The principal entities within this spectrum are tracheobronchomalacia, characterised by weakness of cartilaginous support, and excessive dynamic airway collapse, driven by invagination of the posterior membranous wall. Beyond these, rare tracheobronchial disorders such as tracheobronchopathia osteochondroplastica and tracheal diverticula add further complexity, presenting with nodular or cystic lesions that may exacerbate airflow limitation. Clinically, patients often report chronic cough, exertional dyspnoea, wheezing refractory to standard bronchodilator therapy and recurrent respiratory infections. Diagnosis relies on a combination of dynamic imaging—principally expiratory computed tomography—and direct visualisation via flexible bronchoscopy. Functional evaluation, including flow–volume loops and measurement of intraluminal pressure changes, aids in quantifying the degree of collapse. Management strategies range from conservative measures, such as positive airway pressure and targeted physiotherapy, to interventional approaches including endoluminal stenting, surgical tracheobronchoplasty and, in selected cases, laser tracheobronchoplasty. Advances in understanding the cellular and molecular underpinnings of these disorders have opened potential pathways for medical therapies aimed at restoring airway wall integrity and modulating aberrant tissue remodelling.

Research from Nature Portfolio

Recent studies have uncovered a central role for airway basal stem cells in the pathogenesis of tracheobronchopathia osteochondroplastica, an under‐recognised tracheobronchial disorder marked by heterotopic bone and cartilage nodules. Genome‐wide transcriptional and epigenetic analyses reveal that these basal cells act as reservoirs for inflammatory and TGFβ–BMP signals, driving both epithelial metaplasia and mesenchymal osteo‐chondrogenesis through extracellular matrix remodelling. Restoration of the local microenvironment—either by correcting basal cell function or by pharmacological modulation of key signalling pathways—emerges as a promising avenue for targeted therapy in this condition.

Dynamic Airway Collapse and Tracheobronchial Disorders publication trend

The graph below shows the total number of articles in dynamic airway collapse and tracheobronchial disorders across all publications each year (not limited to Nature Index journals).

Technical terms

Dynamic airway collapse: Reversible narrowing of the trachea and bronchi during the respiratory cycle due to loss of airway wall support.

Tracheobronchomalacia: Structural weakness of tracheal or bronchial cartilage leading to excessive airway collapse on exhalation.

Excessive dynamic airway collapse (EDAC): Prominent invagination of the posterior membranous wall into the airway lumen during expiration without cartilage weakness.

Tracheobronchopathia osteochondroplastica: Rare benign disorder characterised by submucosal osseous and cartilaginous nodules protruding into the tracheal and bronchial lumen.

Dynamic expiratory CT: Imaging technique capturing airway dimensions during forced or tidal exhalation to assess airway collapsibility.

Laser tracheobronchoplasty: Endoscopic procedure utilising laser‐induced fibrosis of the airway wall to stiffen and stabilise collapsible segments.

References

1. Malfunction of airway basal stem cells plays a crucial role in pathophysiology of tracheobronchopathia osteoplastica. Nature Communications (2022).
2. Detection and diagnosis of large airway collapse: a systematic review. ERJ Open Research (2021).
3. Expiratory central airway collapse in stable COPD and during exacerbations. Respiratory Research (2017).
4. Laser tracheobronchoplasty: a novel technique for the treatment of symptomatic tracheobronchomalacia. European Archives of Oto-Rhino-Laryngology (2016).