Aim: Sensorineural hearing loss, which is limited to the cochlear basal turn, due to acute or chronic otitis media has been reported in clinical studies and experimental studies. In the present study, the effect of intratympanic dexamethasone on endotoxin-induced cochlear damage was investigated by measuring the cochlear blood flow and hearing. Materials and Methods: Ten male Sprague-Dawley rats. Those animals inoculated with lipopolysaccharide(LPS) were divided into 2 groups of five rats each. One hour after intratympanic inoculation, the group A received 40 Ìlof phosphate-buffered saline (PBS) in the right middle ear cavity, group B received 40 Ìl of dexamethasone. The treated animals were examined 24h after inoculation using auditory brain stem response (ABR) and cochlear blood flow (CBF). Results: The elevated threshold decreased significantly after intratympanic dexamethasone administration compared with the PBS treated group. Intratympanic dexamethasone administration to the round window of rats led to a statistically significant increase in CBF compared with the PBS treated group (p<0.05). The response to round window application of prostaglandin E1 (PGE1) in the dexamethasone treated group was better in the PBS treated group. Conclusion: Our results suggested that intratympanic dexamethasone treatment was effective in protecting the function of the cochlea against endotoxin-induced otitis media.
|Number of pages||5|
|Publication status||Published - 2007|