Relationship between distortion product otoacoustic emission signal-to-noise and hearing threshold change during methylprednisolone therapy for sudden deafness

Sudden deafness is an emergency case in audiology requiring immediate treatment. According to the consensus on diagnosis and treatment of sudden hearing loss 2010 in Madrid, Spain, steroid drugs are the treatment of choice for sudden deafness with an unknown etiology. Patients recovering from sudden deafness exhibit increasing otoacoustic emissions that begin prior to hearing improvement. In this study, we evaluated a new methylprednisolone regimen (1 mg/kg daily, tapering by 20 mg every 5 days) for sudden deafness using distortion product otoacoustic emissions (DPOAE) and pure tone audiometry. Pure tone audiometry and DPOAE evaluations were conducted on 22 patients before treatment and on day 15 after therapy. Hearing threshold improved at all measured frequencies during treatment (1500-12000 Hz). There were also significant changes in DPOAE signal-to-noise ratio (SNR) at 1500, 2000, and 8000 Hz. Moreover, there were significant associations between SNR change and hearing threshold change at 8000 Hz and 10000 Hz. Thus, this new methylprednisolone regimen is highly effective for sudden deafness.