Abstract
The inspection of cochlear nerve integrity may be important for diagnosis and managements of patients with profound sensorineural hearing loss (SNHL). Recent studies have described that the high-resolution T2-weighted MRI may be efficient to identify cochlear nerve deficiency (CND) in children with profound SNHL. We report 2 cases with unilateral unexplained progressive sensorineural hearing loss associated with the CND. A 20-year-old woman showed a profound SNHL in audiogram and no response in auditory brainstem response (ABR) in her right ear, however she showed almost normal responses in both ears using distortion product otoacoustic emissions (DPOAE). Another case was a 12-year-old boy, who showed a SNHL in high frequency and no response in ABR and poor response at high frequency in DPOAE. In affected side of these patients with high-resolution T2-weighted MRI, the CND was observed, and high resolution CT showed the hypoplasia of bony cochlear nerve canal (BCNC). Therefore, we suggest that the high resolution T2-weighted MRI is essential to detect the CND associated with unexplained sensorineural hearing loss.
