Profound hearing loss attributable to cochlear nerve disease: Diagnosis with combination of otoacoustic emission and magnetic resonance imaging

Objective: To detect the causes of deafness based on the combined findings of auditory brainstem response (ABR), distortion product otoacoustic emissi ons (DPOAEs), and three-dimensional Fourier transformation-constructive int erference in steady state (3DFT-CISS) magnetic resonance imaging (MRI), Stu dy Design: Retrospective review of the medical records of 13 patients with unilateral profound hearing loss since childhood. Methods: Subjects were te sted with pure-tone audiometry, ABR, DPOAEs, and 3DFT-CISS imaging Results: No significant components of ABR were observable in any of the deaf ears. In 10 cases, the cochlear nerves of the deaf ears were found to be as norma l as the healthy sides by 3DFT-CISS imaging, and no significant levels of D POAEs were recorded. In the other three cases, no apparent cochlear nerves were identified by 3DFT-CISS imaging. Although no significant levels of DPO AEs were observable in two cases with cochlear nerves invisible by the MRI study, almost the same level of DPOAEs as that in the healthy side was reco rded in the last case. Conclusions: In the last particular case, the cochle ar nerve seemed to be mainly responsible for the profound deafness. 3DFT-CI SS imaging in combination with preexisting audiological measures may provid e direct evidence for the cochlear nerve disease.