Airway changes following Le Fort III distraction osteogenesis for syndromic craniosynostosis: a clinical and cephalometric study.

Background: Le Fort III distraction osteogenesis improves midface form and dental relationships in patients with syndromic craniosynostosis, but its effect on the upper airway is not well documented. Methods: A retrospective review was conducted of patients with syndromic craniosynostosis undergoing Le Fort III distraction osteogenesis from 2000 to 2006 (n = 20). Changes in velar angle and nasopharyngeal, velopharyngeal, oropharyngeal, and hypopharyngeal spaces were measured cephalometrically. Three-dimensional airway casts were created from computed tomographic data to ascertain circumferential airspace changes. Patients with the preoperative diagnosis of severe obstructive sleep apnea or a tracheostomy were designated as having significant airway compromise. Cephalometric differences in the preoperative superior airspace were compared between patients with and without significant airway compromise. Improvement in the symptoms of obstructive sleep apnea was studied. Results: Cephalometric analysis revealed an increase in the velar angle (121 degrees to 148 degrees; p < 0.001) and an increase in the nasopharyngeal (3.9 mm to 13.0 mm; p < 0.001) and velopharyngeal airspaces (2.0 mm to 5.9 mm; p< 0.01). Three-dimensional computed tomographic analysis confirmed these findings. Comparison between preoperative cephalograms of patients with (n = 10) and without significant airway compromise (n = 10) revealed smaller nasopharyngeal (2.2 mm versus 5.7 mm; p < 0.05) and velopharyngeal airspaces (0.9 mm versus 3.0 mm; p= 0.05). Nine of 10 patients with significant airway compromise experienced improvement in their symptoms of obstructive sleep apnea or had their tracheostomy removed. Conclusions: Le Fort III distraction osteogenesis significantly increases nasopharyngeal and velopharyngeal airspaces in patients with syndromic craniosynostosis. Midface distraction improves but does not resolve all causes of obstructive sleep apnea in this patient population.