Image-Based Computational Fluid Dynamics Evaluation of the Impact of Tracheomalacia Severity on Airflow Dynamics

Tracheomalacia is a congenital disease characterized by dynamic tracheal narrowing throughout respiration. Severity of the collapsing region and patient symptoms vary. In the most severe cases, respiratory failure can occur and reconstructive airway surgery is indicated for definitive treatment. In this study, computational fluid dynamics (CFD) is used to assess airflow in tracheomalacia patients and healthy controls. Patient-specific geometries reconstructed from 4D-CT scans were discretized with a dynamic mesh approach, to capture the trachea wall deformation and simulate the strong effect of this dynamic collapse on the air flow. Flow metrics such as maximum and mean airway velocities, pressure drop, airway resistance, work of breathing/dissipation, and wall shear stress maximum/minimum in the malacic region were evaluated. These metrics help characterize the impact of varying tracheomalacia severity on airflow dynamics in the trachea and respiratory function. The findings of this study have the potential to advance non-invasive assessment of tracheomalacia, support clinicians quantitative planning of patient-specific treatments for tracheomalacia, and support evidence-based, rigorous analysis of the most effective intervention prior to treatment.