Introduction: Benign scarring central airway stenosis can be managed by high-pressure balloon dilatation, laser, surgery and stent implantation. The stenosis may have a high recurrence rate that necessitates repeated treatment. Pirfenidone (PFD) has anti-fibrosis effects and has been used in a variety of fibrosis diseases. Animal experiments suggested that PFD can prevent tracheal stenosis. Patient concerns: Patients with scarring central airway stenosis usually have chest tightness, cough and dyspnea. Diagnosis: Computed tomography scanning showed stenosis of the trachea and/or bronchus. Bronchoscopy revealed occlusion or stenosis of the trachea or bronchus. Interventions: The use of PFD in combination with other interventional management was reported to treat 2 cases of tracheobronchial stenosis after injury in this study. In the combined use of PFD and interventional management, PFD could help to alleviate tracheobronchial stenosis, prolong the time interval of bronchoscopic interventional treatment, and reduce medical costs. Outcomes: The stenosis in the trachea and/or bronchus is relieved and the patients do not have any relevant symptoms.

Rapid urbanization has intensified jobs–housing separation and increased commuting distances in megacities, posing challenges for sustainable urban development. Existing studies often examine commuting behavior at a single spatial scale or focus on either residential or employment locations. Using mobile phone signaling data, this study derives network-based commuting distances within the suburban ring of Shanghai and integrates multiple built environment indicators. A multiscale framework is developed using six spatial units, ranging from 2 to 4 km grids to street-level zones, to assess spatial scale effects and support the selection of an appropriate analytical unit. The 3.5 km grid was selected for subsequent analysis as a balance between spatial detail and statistical stability. Within this framework, Multiscale Geographically Weighted Regression (MGWR) examines the spatial heterogeneity and scale effects of built environment factors from both residential and employment perspectives. The results show: (1) The choice of spatial unit significantly affects model performance, with the 3.5 km grid providing a suitable balance between spatial detail and statistical stability. (2) Built environment indicators exhibit clear multiscale effects, with different variables operating at global and local spatial scales. (3) Residential and employment locations show significant asymmetric effects, as enterprise density is associated with shorter commuting distances at residential locations but longer distances at employment centers. These findings indicate the joint role of multiscale spatial structure and dual-end built environments, supporting spatially differentiated planning and transport policies.