Pediatric unilateral isolated choanal atresia is not associated with mandibular condyle hypoplasia

We hypothesized that the ontogeny of unilateral isolated choanal atresia involves a field defect manifesting as ipsilateral mandibular condylar hypoplasia. The topic is important because the mechanism of the unilateral isolated choanal atresia is unknown.

Retrospective self-controlled case series. We included 20 patients (2 males and 18 females, ages 2 weeks to 13 years) with unilateral isolated non-syndromic choanal atresia. We studied their high-resolution computed tomographic scans. Two otolaryngologists measured the largest cross-sectional area of the mandibular condyle in the axial plane perpendicular to the posterior border of each mandibular ramus independently. Statistical significance and inter-rater agreement were calculated with paired Wilcoxon rank sum test and Spearman's non-parametric correlation coefficient respectively.

Cross-sectional areas of the condyles ipsilateral to the choanal atresia were not statistically different than those of the contralateral condyle (P = 0.27). Inter-observer agreement of condyle areas was excellent: Spearman's r = 0.85 on the right and r = 0.94 on the left.

In this cohort of children with the rarity of isolated non-syndromic unilateral congenital choanal atresia, no associated mandibular condyle hypoplasia was found. The data suggest that the underlying ontogeny was unlikely attributable to a field defect.