Investigating the Etiopathogenesis of Obstructive Sleep Apnea in Pediatric Patients with Unilateral Craniofacial Microsomia

Abstract

INTRODUCTION: Bilateral craniofacial microsomia is a risk factor for obstructive sleep apnea (OSA).1,2 We hypothesize that unilateral craniofacial microsomia (UCFM) can also be an unrecognized cause of OSA. In this study, we aim to determine and characterize the etiopathogenesis of OSA in patients with UCFM through the use of three dimensional airflow analysis. METHODS: All pediatric patients diagnosed with UCFM at a tertiary level institution from 1990 to 2010 were reviewed. Patients with confirmed diagnoses of OSA (Apnea Hypopnea Index>1) were compared to control patients with UCFM without OSA otherwise randomly selected. Three dimensional analysis of airflow with a computational fluid analysis model was performed (MIMIC software) on a sample of both affected as well as unaffected individuals. CT data was converted into a 3-dimensional computational model where the Navier-Stokes equations governing fluid flow can yield a variety of objective measures of airflow in the given anatomy. RESULTS: 62 patients were identified as having UCFM, 7 patients were further diagnosed with OSA. 11.5% of the patients diagnosed with UCFM were diagnosed with OSA, compared to 2.5% in the healthy pediatric population (p=0.01). 100% of patients with OSA were Pruzanski grades IIB or higher. OSA presenting symptoms included snoaring (71.4%), failure to thrive (FTT) (57.1%), chronic respiratory infections (42.8%), adenotonsillar hypertrophy (28.6%) or loud breathing (28.5 %). Snoring (p<0.001), presence of Goldenhaar features (p=0.001) and FTT (p=0.004) were identified as significant predictors for OSA in patients with UCFM. Race, obesity, cleft lip/palate, upper respiratory complications, presence of adenotonsillar hypertrophy and side of UCFM were not predictors of OSA in our cohort. Patients with UCFM and OSA had significantly lower total flow rate compare to controls. CONCLUSION: The prevalence of OSA in UCFM patients is 3.9 times greater then in the otherwise healthy population. Snoring, presence of Goldenhaar features and FTT were shown to be predictive factors for OSA in the presence of UCFM (Table 1).Table 1: Univariate Analysis.