Therapeutic time window of methylprednisolone in acoustic injury.

HYPOTHESIS: This study aims to investigate the therapeutic time window of methylprednisolone in acoustic injury.

BACKGROUND

Although glucocorticoids have been widely used in the treatment of acoustic injury, the therapeutic time window of glucocorticoids in acoustic injury has never been examined.

METHODS

Mice were exposed to 4-kHz pure tone of 128-dB sound pressure level for 4 hours. Auditory brainstem response was examined before, immediately after, and 2 weeks after acoustic overexposure.

RESULTS

Methylprednisolone significantly improved the auditory brainstem response threshold shifts 2 weeks after acoustic overexposure when it was administered before or immediately after acoustic overexposure, but not when administered 3 hours after acoustic overexposure.

CONCLUSION

The present findings suggest that methylprednisolone possesses protective effects against acoustic injury of the cochlea with a short therapeutic time window.