Mandibular condylar hypoplasia in children with isolated unilateral congenital aural atresia.

OBJECTIVES/HYPOTHESIS We hypothesized that children with isolated nonsyndromic unilateral congenital aural atresia have subclinical mandibular condylar hypoplasia ipsilateral to the atretic ear, and that the Jahrsdoerfer score is associated with the degree of condylar hypoplasia. STUDY DESIGN Retrospective self-controlled case series. METHODS We reviewed high-resolution computed tomography scans of the temporal bones of 68 children with isolated nonsyndromic unilateral congenital aural atresia. Images were viewed in the transverse (axial) plane perpendicular to the axis of the mandibular ramus and scanned from the mandibular notch to the condylar top. The slice where the condyle had the largest cross-sectional area was measured and checked for correlation with atresia status, age, and sex. The Jahrsdoerfer score of the atretic ear was calculated and correlated with condyle cross-sectional area, age, and sex. RESULTS Cross-sectional area of the condyle ipsilateral to the atretic ear was, on average, 8.41 mm2 smaller than the contralateral condyle (P < .0001). The Jahrsdoerfer score was not associated with the condylar cross-sectional area, age, or sex. CONCLUSION Isolated nonsyndromic unilateral congenital aural atresia is associated with mild hypoplasia of the mandibular condyle ipsilateral to the atretic ear. This is consistent with the hypothesis that congenital aural atresia is a variant of craniofacial (hemifacial) microsomia. LEVEL OF EVIDENCE 4. Laryngoscope, 2017.