a) Bronchomalacia
b) Bronchial stenosis
d) Bronchial compression
i) Bronchogenic cysts
ii) Vascular compression
iv) Tumor/lymph nodes
v) Other causes of bronchial compression
e) Bronchoesophageal fistula
f) Endobronchial mass lesions
i) Granulation tissue
ii) Tumors
g) Foreign body aspiration
h) Mucus plugs
i) Hemoptysis
j) Inflammatory conditions
i) Bronchitis
ii) Cystic fibrosis
iii) Primary ciliary dyskinesia
iv) Others