JOURNAL OF LARYNGOLOGY AND OTOLOGY

Objective: This study aimed to present the histopathological and audiological effects of mechanical trauma associated with the placement of a model electrode in the scala tympani in rats, and the effects of continuous topical corticosteroid application. Method: The study comprised three groups of rats. The round window membrane was perforated in all three groups and a model electrode was inserted in the round window. Group one received no further treatments. Groups two and three also had an intrathecal microcatheter compatible with a mini-osmotic pump inserted; in group two this was used to release normal saline and in group three the pump released 400 mu g/ml dexamethasone. Results: Dexamethasone infusion given after implantation of the intracochlear model electrode was more effective for preventing hearing loss than the administration of just one dose of dexamethasone. Conclusion: The findings suggest that continuous dexamethasone infusion is beneficial for preventing the loss of hair cells and neurons associated with early and late periods of intracochlear electrode trauma