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Histopathological and audiological effects of mechanical trauma associated with the placement of an intracochlear electrode, and the benefit of corticosteroid infusion: prospective animal study

  • G Malkoc (a1), A Dalgic (a1), M Koc (a1), T Kandogan (a2), S Korkmaz (a1), M E Ceylan (a1), S Inan (a3) and L Olgun (a1)...



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.


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 µg/ml dexamethasone.


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.


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.


Corresponding author

Address for correspondence: Dr Abdullah Dalgic, Department of Otolaryngology, Head and Neck Surgery, Izmir Bozyaka Research and Training Hospital, Saim Cikrikci Cad. No: 59 Bozyaka, Izmir 35170, Turkey Fax: +90 232 2505050 E-mail:


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Presented orally at the 2nd National Congress of Otology and Neurotology, 10–13 May 2012, Antalya, Turkey.



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Histopathological and audiological effects of mechanical trauma associated with the placement of an intracochlear electrode, and the benefit of corticosteroid infusion: prospective animal study

  • G Malkoc (a1), A Dalgic (a1), M Koc (a1), T Kandogan (a2), S Korkmaz (a1), M E Ceylan (a1), S Inan (a3) and L Olgun (a1)...


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