Reduction of permanent hearingloss by local glucocorticoid application : Guinea pigs with acute acoustic trauma.

Abstract

High-intensity noise exposure from impulse and blast noise events often leads to acute hearing loss and may cause irreversible permanent hearing loss as along-term consequence. Here, atreatment regime was developed to limit permanent damage based on apreclinical animal model of acute noise trauma. To develop clinical trials for the treatment of acute noise traumas using approved drugs. The otoprotective potential of glucocorticoids applied locally to the inner ear was examined. Aseries of experiments with different impulse noise exposures were performed. Permanent hearing loss and hair cell density were assessed 14days after exposure. Hearing and hair cell preservation were investigated as afunction of the glucocorticoid dose. After impulse noise exposure, local application to the round window of the cochlea of high-dose prednisolone (25mg/ml) or methylprednisolone (12.5mg/ml) resulted in astatistically significant reduction in hearing loss compared with the control group. The local application of high doses of the drugs to the round window of the cochlea appears to be an effective treatment for acute noise trauma.