Feasibility of structured light plethysmography for the evaluation of lung function in preschool children with asthma

Background: Structured light plethysmography (SLP) is a new noninvasive technology to capture the movement of the thoracic and abdominal wall, and to assess some parameters indicative for lung function. Objective: The purpose of the study was to evaluate the feasibility of SLP in children with asthma. Methods: A total of 52 patients were enrolled: 25 with asthma exacerbation (group 1), 13 with well-controlled asthma (group 2), and 14 healthy controls (group 3). Every patient underwent SLP evaluation and a lung function test. Results: SLP evaluations showed that the ratio of inspiratory flow at 50% of tidal volume (Vt) to expiratory flow at 50% of Vt, in which Vt is taken to be the exhaled chest wall movement, and flow is taken to be the time derivative of the chest wall movement (IE50) value increased in group 1 compared with groups 2 and 3, with statistical significance (p = 0.018); the data were consistent with the spirometry parameter. A correlation between the IE50 and forced expiratory volume in the first second of expiration was highlighted (r = -0.35, p = 0.019). Conclusion: SLP assessed airway obstruction, and its use in clinical practice could be applied in preschool children in future studies.