A = on sagittal view, the most constricted point of oropharynx was identified manually, as marked by the green double-headed arrow.
B = on the corresponding axial view, the minimal anterior-posterior (AP) and mesial-lateral (ML) dimensions of oropharynx were measured using linear measurement tools of Invivo™ software, as AP = 5.14 mm, and ML = 14.25 mm.
C = total airway volume (10.9 ml) and minimal surface area (61.1 mm2) were automatically calculated by the software.