Distortion product otoacoustic emissions in sheep before and after hyperinsulinemia induction.
نویسندگان
چکیده
UNLABELLED Transient evoked otoacoustic emissions and distortion product otoacoustic emissions have gained significant importance in the identification of cochlear alterations. AIM To record distortion product thresholds through the monitoring of otoacoustic emissions in normal conditions and in the presence of electrophysiologic changes in cochlear outer hair cells in sheep after hyperinsulinemia induction. MATERIAL AND METHODS Experimental study, with seven sheep in the control group and seven in the study group. Insulin and glucose concentrations were measured simultaneously for the recording of distortion product otoacoustic emission every 10 minutes, all the way to 90 minutes. The control group received saline solution, and the study group received a bolus injection of 0.1 U/kg of regular human insulin. RESULTS There was a significant reduction in distortion product thresholds in the study group when compared to the control group at frequencies greater than 1,500 Hz and after 60 minutes (P < 0.001). CONCLUSION This study established distortion product otoacoustic emission thresholds in sheep with constant reproducibility, demonstrating that the method is adequate for use in audiology and otology investigations. Results also fully confirm that acute hyperinsulinemia may cause important changes in these thresholds.
منابع مشابه
Distortion product otoacoustic emissions in an animal model of induced hyperinsulinemia.
The existence of a relationship between abnormal insulin levels and the occurrence of labyrinth disorders has been demonstrated in several works. Among many metabolic alterations, such studies indicate that hyperinsulinemia is one of the most frequent causes of cochlear and vestibular syndromes. In this study, we monitored distortion product evoked otoacoustic emission thresholds during induced...
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ورودعنوان ژورنال:
- Brazilian journal of otorhinolaryngology
دوره 74 2 شماره
صفحات -
تاریخ انتشار 2008