Functional analysis of the airways after pulmonary lobectomy through computational fluid dynamics

Abstract

Pulmonary lobectomy, which consists of the partial or complete resection of a lung lobe, is the gold standard intervention for lung cancer removal. The removal of functional tissue during the surgery and the re-adaptation of the remaining thoracic structures decrease the patient's post-operative pulmonary function. Residual functionality is evaluated through pulmonary function tests, which account for the number of resected segments without considering local structural alterations and provide an average at-the-mouth estimation. Computational Fluid Dynamics (CFD) has been demonstrated to provide patient-specific, quantitative, and local information about airways airflow dynamics. A CFD investigation was performed on image-based airway trees reconstructed before and after the surgery for twelve patients who underwent lobectomy at different lobes. The geometrical alterations and the variations in fluid dynamics parameters and in lobar ventilation between the pre and post-operative conditions were evaluated. The post-operative function was estimated and compared with current clinical algorithms and with actual clinical data. The post-operative configuration revealed a high intersubject variability: regardless of the lobectomy site, an increment of global velocity, wall pressure, and wall shear stress was observed. Local flow disturbances also emerged at, and downstream of, the resection site. The analysis of lobar ventilation showed severe variations in the volume flow rate distribution, highlighting the compensatory effects in the contralateral lung with an increment of inflow. The estimation of post-operative function through CFD was comparable with the current clinical algorithm and the actual spirometric measurements. The results confirmed that CFD could provide additional information to support the current clinical approaches both in the operability assessment and in the prescription of personalized respiratory rehabilitation.

Quantifying ventilation by X-ray velocimetry in healthy adults

“…XV has the potential to characterize how tidal volume and flow rate vary across different lobes and segments of the right and left lung with further validation of regional assessments of ventilation heterogenity [ 13 , 14 ]. Regional partitioning of tidal volume and flow rates has clinical relevance.…”

Rapid Recovery of Postoperative Pulmonary Function in Patients With Lung Cancer and Influencing Factors

“…Surgery is the first-line treatment for early-stage lung cancers, and the preoperative pulmonary function status and surgical methods are important factors affecting the prognosis and quality of life ( 2 ). With an inability to regenerate new tissues from residual pulmonary tissues, the surgical excision of functional tissues and reconstruction of residual thoracic structures results in reduced postoperative pulmonary function ( 3 ). In particular, wide ranging complications resulting from reduced respiratory function caused by pneumonectomy are major reasons for poor postoperative quality of life ( 4 ).…”