Airway Morphological Changes in Pierre Robin Sequence: A Retrospective Study

Objective: To investigate airway morphology changes in patients with Pierre Robin sequence (PRS) pre-/post-mandibular distraction osteogenesis (MDO) and to compare morphologic changes to age-matched controls. Design: Retrospective case-control study. Setting: Urban, academic, tertiary medical center. Patients, Participants: Fifteen patients with PRS after MDO to relieve upper airway obstruction (UAO) (2008-2018); age-matched controls for post-MDO patients. Interventions: Mandibular distraction osteogenesis, curvilinear internal mandibular distractors. Main Outcome Measures: (1) Physiologic improvement after MDO (apnea-hypopnea index; minimum oxygen saturation); (2) airway size (volume, surface area, length, mean/minimum cross-sectional area), shape (lateral:anterior-posterior ratio, cross-sectional area ratios, uniformity, sphericity), and changes with MDO; and (3) post-MDO airway size, shape versus age-matched controls. Results: Airway size increased after MDO (volume,P= .01; surface area,P= .02; length,P= .01), as did cross-sectional area (mean,P= .02; minimum,P= .02; minimum retropalatal,P= .05, mid-retroglossal,P= .02). Post-MDO PRS airways were larger than controls (volume,P< .01; surface area,P< .01; length,P< .01, cross-sectional area,P= .03). Airway shape remained nonuniform and flat post-MDO; control airways were round. Two syndromic patients required repeat MDO and had subphysiologic post-MDO airway cross-sectional area. Post-MDO PRS patients with supraphysiologic cross-sectional area along the entire airway had no UAO recurrence. Conclusions: In this small, heterogenous patient sample, MDO increases airway size, may preferentially affect the retropalatal airway, and often results in supraphysiologic airway dimensions. These retropalatal changes may be important in relieving severe UAO in patients with PRS. Generalizability of our results is limited by small cohort size and patient heterogeneity.