Effects of unilateral vertical mandibular distraction osteogenesis on airway anatomy in children with hemifacial microsomia.

PURPOSE: To assess the two- and three-dimensional airway changes following unilateral vertical mandibular distraction osteogenesis (vMDO) in patients with hemifacial microsomia (HFM).

METHODS

A retrospective evaluation was performed for consecutive patients over an 18-month period with HFM and with Kaban-Pruzansky Type-II mandibular deformities who underwent unilateral vMDO for correction of vertical mandibular asymmetry. Patients with complete records and a minimum of 12 months of clinical follow-up post-consolidation were included. Pre-operative airway dimensions (diameters, cross-sectional areas, and volumes) were measured for the oropharynx and nasopharynx. Pre-operative airway dimensions were compared to post-distraction measurements taken from 3D-CT data obtained at a minimum of 3 months post-consolidation.

RESULTS

Five patients met inclusion criteria. Median age was 12.6 years, 3 were female, and median distraction length was 21.3 mm. Median final follow-up CT was performed 5 months after completion of distraction. There were no major or minor complications. Median total airway volume change was +33.7%, corresponding to median volume changes of 80.5% and 10.5% for the oropharyngeal and nasopharyngeal airways, respectively.

CONCLUSION

Unilateral vMDO expands the minimum diameter and volume of the oropharyngeal to a greater extent than the nasopharyngeal airway in HFM patients with Kaban-Pruzansky Type-II mandibular deformities.