Defining failure and its predictors in mandibular distraction for Robin sequence

Abstract

Introduction: Robin sequence (RS) is defined as the triad of micrognathia, glossoptosis and airway obstruction. A popular surgical treatment is mandibular distraction osteogenesis (MDO). In this study, it is demonstrated that the associated variables change, dependent on the manner in which failure is defined. These multiple failure outcomes are used to construct a scoring system to predict MDO failure.

Methods: A retrospective database of neonatal MDO patients was constructed. Failure outcomes studied included tracheostomy; a decrease in the apnea-hypopnea index (AHI) but an AHI >20; and death. A combination of bivariate and regression analysis was used to produce significantly associated variables and a scoring system.

Results: Statistical analysis demonstrated the association of gastroesophageal reflux; age >30 days; neurologic anomaly; airway anomalies, other than laryngomalacia; an intact palate; and pre-operative intubation on the outcome variables studied. Multiple scoring systems were produced with reasonable sensitivity, specificity, and positive and negative predictive value.

Conclusions: When reporting surgical outcomes of MDO in the setting of RS, it is important to consider the AHI as well as avoidance of tracheostomy as an outcome variable. Incomplete amelioration of AHI accounts for half of the patients with a problem after MDO. The predictive scores presented will be used and validated on a larger, prospectively collected dataset.

Keywords: Avoidance of tracheostomy; Mandibular distraction osteogenesis; Pierre Robin sequence; Predictors of failure.