CC-BY-NC-ND 4.0 · Int Arch Otorhinolaryngol 2018; 22(02): 171-176
DOI: 10.1055/s-0037-1604067
Original Research
Thieme Revinter Publicações Ltda Rio de Janeiro, Brazil

The Effects of Experimental Intratympanic Steroid Administration on Organ of Corti Type 1 Spiral Ganglion

Turgay Topcuoglu
Department of Otolaryngology, Arnavutkoy State Hospital, Istanbul, Turkey
,
Murat Kocyıgıt
Department of Otolaryngology, Kanuni Sultan Süleyman Education and Research Hospital, Istanbul, Turkey
,
Erdogan Bulut
Department of Audiology, Faculty of Health Sciences, Balkan Campus, Trakya University Edirne, Turkey
,
Safiye G. Ortekın
Department of Otolaryngology, Kanuni Sultan Süleyman Education and Research Hospital, Istanbul, Turkey
,
Mehmet Kanter
Department of Histology and Embryology, Medeniyet University, Istanbul, Turkey
,
Recep Yagız
Department of Otolaryngology, Trakya University, Edirne, Turkey
› Author Affiliations
Further Information

Publication History

13 December 2016

12 April 2017

Publication Date:
14 July 2017 (eFirst)

Abstract

Introduction It is unclear how effective is the intratympanic (IT) steroid treatment on organ of Corti type 1 spiral ganglion, its optimal dosage and frequency of administration. The effect of dexamethasone on cochlear functions in individuals with a normal hearing ability is also unknown.

Objective The aim of this study was to evaluate, at the electrophysiological and ultrastructural levels, the effect of IT dexamethasone administration in guinea pigs with normal hearing on organ of Corti type 1 spiral ganglion.

Methods A total of 20 guinea pigs (n = 40 ears) whose hearing was detected to be normal by electrophysiological tests were included in the study and randomly divided into 6 groups. Four groups were considered study groups, while 2 groups were considered control groups. Dexamethasone was administered intratympanically in doses of 2 mg/mL and 4 mg/mL in the guinea pigs in the study groups. The animals in the control groups received physiological saline in equal doses as the study groups. All interventions were performed under general anesthesia, and the electrophysiological tests were repeated following the IT injections.

Results No statistically significant differences were found among the groups when the IT injections were evaluated in terms of the electrophysiological measurements (p > 0.05). The ultrastructural evaluation showed a cellular mitochondrial increase in the spiral ganglions of the cochlea in the groups in which dexamethasone was administered in a dose of 4 mg/mL.

Conclusion According to the findings of this study, it can be suggested that the IT injection of dexamethasone is safe, and when applied in a dose of 4 mg/mL, it increases metabolic activity at the cellular level.