Bringing stability to excessive central airway collapse: tracheobronchoplasty and the impact on distinct airway disorders

While tracheobronchomalacia (TBM) and excessive dynamic airway collapse (EDAC) represent two distinct pathologies, these diseases are often grouped under the unifying term of excessive central airway collapse (ECAC). TBM is diagnosed in the setting of a weakening and loss of curvature of the anterior cartilaginous tracheal rings while EDAC is defined by its excessive invagination of the lax posterior tracheal membrane narrowing the airway lumen. Both lead to occlusion and loss of airway patency resulting in a clinical overlap among presentation, diagnostic pathway, and treatment paradigms. Furthermore, mixed features of both EDAC and TBM may be present on imaging studies and dynamic bronchoscopy, thus leading to inappropriate classification and missed opportunities for definitive treatment (1).

The study by Cho and colleagues excellently highlights tracheobronchoplasty (TBP) as the appropriate treatment for patients with severe (>90% collapse) ECAC regardless of etiology (TBM or EDAC) (2). TBP is a procedure in which a stabilizing material, such as a non-absorbable polypropylene mesh, is sutured along the posterior membrane. This achieves the goal of splinting the posterior membranous wall of the central airways preventing excessive collapse. There is variation in practice as to the performance of TBP via an open thoracotomy approach or a robotic-assisted approach (3). Furthermore, there is variation as to how to suture the polypropylene mesh to the posterior membrane of the large airways, as some have described a horizontal suture technique (4) while others have used a vertical suture method (5).

While data have shown excellent outcomes for patients with ECAC who undergo TBP (6,7), irrespective of surgical approach (i.e., open thoracotomy vs. robot-assisted) there has always been a gap in the literature as authors have failed to highlight outcomes for the two distinct pathologies that comprise ECAC. Additionally, some institutions may have varying surgical approaches for EDAC vs. TBM as some argue that TBP for TBM may best be performed via open approach to ensure greater degree of tension on the mesh (2). Both robotic and open approaches have been described for TBM and EDAC. In EDAC, the pathology lies in the hypermobile posterior membrane with a preserved D-shaped anterior tracheal cartilage rings; whereas in TBM, the pathology lies in the weakened anterior cartilage, resulting in a widened trachea. While EDAC can be managed by splinting the membranous wall alone with a stabilizing material, surgical management of TBM will require estimating the width of the new membranous wall post-splinting to reconstruct a D-shaped trachea (8).

It is in this context that Cho and colleagues have stepped in to attempt to fill this knowledge gap. The paper by Cho and colleagues is one of the largest studies to date comparing head-to-head outcomes of TBP for EDAC vs. TBM.

The authors performed a retrospective study looking at outcomes for a total of 100 patients with severe (defined as >90% collapse) ECAC who underwent TBP. Patients were divided into their pathological sub-group of ECAC (TBM vs. EDAC) based on expert review of pre-operative images. The group of experts reviewing pre-operative images consisted of two thoracic surgeons and two interventional pulmonologists from a high-volume referral center familiar with diagnosing and managing ECAC. Three select dynamic computed tomography (CT) images were reviewed for every patient by this expert panel at multiple anatomic levels: the thoracic inlet, 1 cm above the carina, and 1 cm below the carina. Based upon these images, the panel subdivided each patient into 1 of 4 categories: EDAC, TBM, normal airway or unable to determine. Patients were placed into each of the four categories based on majority consensus. Ultimately, 49 patients were placed into the EDAC cohort and 28 in the TBM (1 patient was placed in the unable to determine group and 10 were placed in the normal airway group). Twelve patients were excluded due to the fact that majority consensus could not be reached regarding diagnosis in these patients.

No key demographic differences or composite comorbidity scores existed between the TBM and the EDAC group. Notably, the median body mass index in both groups was greater than 30 kg/m². A significant proportion of patients with EDAC were more likely to undergo robotic-assisted TBP as compared to patients who were given a TBM diagnosis. However, no differences existed among the operative time, blood loss, intensive care unit length of stay (LOS) and readmission rates. The key finding of this paper is that there were no significant differences in overall complications between the two groups including: respiratory infections, postoperative bronchoscopy, prolonged intubation, or Clavien-Dindo scores. However, there does appear to be a trend towards fewer minor complications in the EDAC group (61%) as compared to the TBM group (81%) (P=0.07) and a signal of more major complications in the TBM group (35%) vs. the EDAC group (21%). Lastly, there were no significant differences in patient quality of life scores.

Several key aspects of this paper should be highlighted. Due to its retrospective nature, patients were assigned to a TBM or EDAC cohort post facto based on radiographic interpretation and not via gold bronchoscopic images. This limitation is highlighted by the fact that 10 patients were classified as having normal airways based on the CT findings, despite having already been given a prior diagnosis of severe ECAC and having undergone TBP. We suspect these patients likely had a confirmed diagnosis based on bronchoscopy. Additionally, one key difference that existed between the two groups was the number of patients undergoing robotic-assisted TBP (30% of patients with EDAC and 4% of patients with TBM, P=0.01). Little data exist comparing robotic-assisted TBP to open thoracotomy TBP head-to-head. However, recent data has shown no difference in outcomes for these two approaches (9,10). Thus, the current work might serve to highlight that there is no difference in outcomes of both Robot-assisted TBP as compared to open thoracotomy TBP as well as the two distinct pathologies (TBM and EDAC) that fall under the umbrella of ECAC. Prior studies suggest that outcomes following tracheobronchoplasty can differ based on idiopathic versus acquired etiologies of EDAC and TBM; consideration of this distinction may further contextualize the authors’ findings.

While diagnostic ambiguity and difficulty remain for differentiating EDAC and TBM, it is unclear if this distinction ultimately matters clinically given the overlapping clinical presentation that exists between these two entities such as barking cough and dyspnea (11). The authors excellently demonstrate no difference in outcomes for EDAC and TBM making this distinction even less clinically meaningful.

What does seem important is appropriate patient selection for TBP. These patients often have multiple medical comorbidities such as chronic obstructive pulmonary disease (COPD) and gastroesophageal reflux disease (GERD). It is imperative that these comorbidities are optimized prior to TBP. Additionally, patients with severe collapse should undergo a stent trial to confirm improvement in symptoms prior to definitive surgical intervention (12). Stent trials are a key step in the management algorithm as the stent serves as a temporary scaffold much in the same way a mesh would, thus assessing physiologic response to eliminating the airway collapse. Furthermore, stents in severe TBM have been shown to improve symptoms, quality of life, and dyspnea in patients with severe TBM and thus should not be overlooked in the management pathway (13). Cho and colleagues did not include in their report the number of patients who had undergone stent trials prior to surgical intervention, duration of stent trial and the indication for surgical intervention.

Several limitations exist with the current paper published by Cho and colleagues. Due to its retrospective nature and small sample size, it is difficult to assess for possible confounders. It is possible that there may have been inherent selection bias within the TBM group based on selection for candidacy for TBP alone. As such, this creates potential selection bias limiting comparison to the EDAC group. Furthermore, while no statistical differences existed in outcomes, clinical differences in outcomes may in fact exist between the two groups (as demonstrated by the higher complication rate seen in the TBM group). Most importantly, diagnoses were assigned based on radiographic definitions and not bronchoscopic definitions, an important variation from the gold standard assessment method. The heterogeneity in this study complicates our ability to compare these two groups. However, it should be noted that these data are reported by an institution highly experienced in tracheobronchoplasty.

This area highlights the need for a multi-disciplinary approach between radiologists, pulmonologists, interventional pulmonologists and thoracic surgeons with regard to the diagnosis and management of ECAC. Larger studies among collaborating institutions are needed to further investigate outcomes for robotic-assisted TBP and comparative outcomes of TBM and EDAC. A multi-disciplinary approach among multiple experts may then lead to a more personalized approach for the patient, ultimately improving patient outcomes.

Acknowledgments

None.

Footnote

Provenance and Peer Review: This article was commissioned by the editorial office, Current Challenges in Thoracic Surgery. The article has undergone external peer review.

Peer Review File: Available at https://ccts.amegroups.com/article/view/10.21037/ccts-2025-1-50/prf

Funding: None.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://ccts.amegroups.com/article/view/10.21037/ccts-2025-1-50/coif). The authors have no conflicts of interest to declare.

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References

1. Aslam A, De Luis Cardenas J, Morrison RJ, et al. Tracheobronchomalacia and Excessive Dynamic Airway Collapse: Current Concepts and Future Directions. Radiographics 2022;42:1012-27. [Crossref] [PubMed]
2. Cho JM, de Angelis P, Mathew F, et al. Tracheobronchoplasty for Excessive Dynamic Airway Collapse and Tracheobronchomalacia: A Comparative Analysis of Distinct Airway Disorders. Ann Thorac Surg 2025;120:1062-70. [Crossref] [PubMed]
3. Bakhos CT, Magarinos J, Bent D, et al. Tracheobronchoplasty for tracheobronchomalacia. J Vis Surg 2022;8:15. [Crossref] [PubMed]
4. Gangadharan SP, Bakhos CT, Majid A, et al. Technical aspects and outcomes of tracheobronchoplasty for severe tracheobronchomalacia. Ann Thorac Surg 2011;91:1574-80; discussion 1580-1. [Crossref] [PubMed]
5. Campisi A, Winter H, Heussel CP, et al. Robotic tracheobronchoplasty with vertical suturing for excessive dynamic airway collapse. JTCVS Tech 2025;31:195-7. [Crossref] [PubMed]
6. Buitrago DH, Majid A, Alape DE, et al. Single-Center Experience of Tracheobronchoplasty for Tracheobronchomalacia: Perioperative Outcomes. Ann Thorac Surg 2018;106:909-15. [Crossref] [PubMed]
7. Lazzaro R, Patton B, Lee P, et al. First series of minimally invasive, robot-assisted tracheobronchoplasty with mesh for severe tracheobronchomalacia. J Thorac Cardiovasc Surg 2019;157:791-800. [Crossref] [PubMed]
8. Wright CD, Mathisen DJ. Tracheobronchoplasty for tracheomalacia. Ann Cardiothorac Surg 2018;7:261-5. [Crossref] [PubMed]
9. Cho JM, Carpenter SL, Mathew F, et al. The first comparative analysis of open and robotic tracheobronchoplasty for excessive central airway collapse†. Eur J Cardiothorac Surg 2025;67:ezaf026. [Crossref] [PubMed]
10. Vaca-Cartagena BF, Funes-Ferrada R, Barrios-Ruiz A, et al. Evaluating long-term bronchoscopic outcomes of tracheobronchoplasty in patients with expiratory central airway collapse. J Thorac Dis 2025;17:2901-11. [Crossref] [PubMed]
11. Gangadharan SP. Tracheobronchomalacia in adults. Semin Thorac Cardiovasc Surg 2010;22:165-73. [Crossref] [PubMed]
12. Majid A, Alape D, Kheir F, et al. Short-Term Use of Uncovered Self-Expanding Metallic Airway Stents for Severe Expiratory Central Airway Collapse. Respiration 2016;92:389-96. [Crossref] [PubMed]
13. Ernst A, Majid A, Feller-Kopman D, et al. Airway stabilization with silicone stents for treating adult tracheobronchomalacia: a prospective observational study. Chest 2007;132:609-16. [Crossref] [PubMed]