- •In this study, we found that the ‘knee’ in spirometry flow-volume curves was often associated with an airway condition in children.
- •Tracheomalacia diagnosed by flexible bronchoscopy was found in 65% of children with the ‘knee’ pattern.
- •A scoop before plateau of the ‘knee’ was significantly associated with tracheomalacia diagnosed by flexible bronchoscopy.
Abbreviations:TM (tracheomalacia), FB (flexible bronchoscopy), ERS (European Respiratory Society), FEV1 (forced expiratory volume in first second), FVC (forced vital capacity), FEF25–75% (forced expiratory flow between 25% and 75% of vital capacity), PEF (peak expiratory flow)
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