Evaluation With Scans and Pharyngometry of the Possible Changes in Upper Airway Geometry Induced by Using Different Mouthpieces.

In this study the possible changes in upper airway geometry induced by variations in the characteristics of the mouthpieces of inhalers will be evaluated with functional respiratory imaging (FRI) and Pharyngometry. The study population consists of 12 healthy male subjects. Different mouthpiece designs will be evaluated for each subject by using magnetic resonance imaging (MRI) scans. The results will help to identify the influence of the height, width, protrusion and resistance of the mouthpiece on upper airway geometry. Pharyngometry profiles of all subjects, whilst inhaling through different mouthpiece variants, in supine and upright position, will be completed. A computed tomography (CT) scan and a cone beam computed tomography (CBCT) scan of the upper airway will be taken to respectively compare the time dependence on 3D imaging with MRI and to provide a 3D image in an upright position. Dental impressions will be optically scanned to obtain a more accurate representation of the oral cavity, mainly in MRI.