Fig. 1From: What is the impact of distraction osteogenesis on the upper airway of hemifacial microsomia patient with obstructive sleep apnea: a case reportThe reconstructed upper airway. a Pre-distraction: I—the choana plane, II—the plane parallel to Frankfort horizontal plane through PNS (posterior nasal spine), III—the minimum cross-sectional area plane, IV—the plane parallel to Frankfort horizontal plane through the superior border of the epiglottis, V—the plane parallel to Frankfort horizontal plane through the most anterior superior edge of the fourth cervical vertebra. b Post-distraction: Lnp—length of the nasopharynx, Lop—length of the oropharynx, Lhp—length of the hypopharynxBack to article page