A case with the bilateral narrow bony cochlear nerve canals associated with near normal hearing thresholds.

The narrow bony cochlear nerve canal in high resolution temporal bone computed tomography is frequently found in patients of congenital sensorineural hearing loss. But this bony structural anomaly could not conclude the functional outcome of cochlear nerve. Here, we present a case of a 14-month-old girl having bilateral narrow bony cochlear nerve canals. In magnetic resonance imaging, both the cochlear nerves were identified to be intact. Moreover, acoustic brainstem response threshold and auditory steady state response revealed nearly normal hearing thresholds. Therefore, we suggest that the narrow bony cochlear nerve canal itself does not necessarily indicate a substantial degree of hearing loss.