Inner ear anomalies in children with isolated unilateral congenital aural atresia

We aim to define the frequencies of anomalies of the inner ear, oval window, and round window ipsilateral to isolated non-syndromic unilateral aural atresia.

Retrospective case series. We reviewed high resolution computed tomography scans of the temporal bones of 70 children with isolated non-syndromic unilateral congenital aural atresia. Scans were reviewed according to the Jahrsdoerfer criteria and further evaluated for anomalies of the vestibule, semi-circular canals, cochlea, internal auditory canal and vestibulocochlear nerve.

Inner ear dysplasia was seen in two of 70 atretic ears: one with a dysmorphic lateral semicircular canal and another with a large vestibule assimilating the lateral semicircular canal. Abnormalities of the oval window and round window ipsilateral to the atresia were identified in 21% (15) and 7% (5), respectively, of the atretic ears. Oval window and round window abnormalities were associated with disproportionately lower Jahrsdoerfer scores compared to aural atresia patients without these abnormalities (P < 0.001 and P = 0.04, respectively).

Compared to studies that included syndromic or bilateral atresia cases, we found inner ear and oval window abnormalities less common in children with isolated non-syndromic unilateral aural atresia. However, round window anomalies seem to occur at about the same frequency.