OBJECTIVES/HYPOTHESIS To investigate the hearing protective effects of methylprednisolone use during radiotherapy in patients with nasopharyngeal carcinoma. STUDY DESIGN Prospective, controlled clinical study. METHODS Fifty-three patients with nasopharyngeal carcinoma (106 ears). Twenty-five patients (50 ears) received radiotherapy with intravenous methylprednisolone for 14 days, and anothe...

Objective This study aimed to investigate possible ototoxicity associated with topical rifamycin application via electrophysiological tests and ultrastructural examinations. Methods Electrophysiological assessment was performed with tympanometry, auditory brainstem response (ABR), and distortion product otoacoustic emission (DPOAE) measurements. This study was conducted on 40 ears of 20 guine...

This paper tests key predictions of the "two-mechanism model" for the generation of distortion-product otoacoustic emissions (DPOAEs). The two-mechanism model asserts that lower-sideband DPOAEs constitute a mixture of emissions arising not simply from two distinct cochlear locations (as is now well established) but, more importantly, by two fundamentally different mechanisms: nonlinear distorti...

We have measured the changes in transient otoacoustic emissions (TEOAEs) and distortion product otoacoustic emissions (DPOAEs) during and after ototoxic amikacin treatment in an animal (chinchilla) model. TEOAE and DPOAE were recorded from 6 adult chinchillas over a 6-week time course starting just before a 5-day or 7-day treatment period with amikacin sulphate (400 mg/kg/day, i.m.). After fina...

Anesthesia effects on otoacoustic emission (OAE) recordings were evaluated in a group of 72 Sprague-Dawley rats (mean weight 225+/-20 gr). Two anesthesia dosages (high and normal) and two anesthetic protocols (ketamine-xylazine, ketamine-xylazine-atropine) were tested. Transient evoked OAE (TEOAE) and distortion product OAE (DPOAE) responses were recorded in 10 min intervals, for a total period...

Distortion product otoacoustic emissions (DPOAE) measured in human newborns are not adult-like. More than a decade of work from various investigators has created a well-developed body of evidence describing these differences but the putative anatomy or physiology has only been partially explained. Recently, Abdala and Keefe [J. Acoust. Soc. Am. 120, 3832-3842 (2006)] have identified outer and m...

INTRODUCTION A nonbehavioral method for monitoring ototoxicity in patients treated with cisplatin is needed because patients enduring chemotherapy may not be well or cooperative enough to undergo repeated hearing tests. Distortion-product otoacoustic emissions (DPOAEs) provide a nonbehavioral measure of auditory function that is sensitive to cisplatin exposure. However, interpreting DPOAE findi...

OBJECTIVES Distortion-product otoacoustic emissions (DPOAEs) collected after sound pressure level (SPL) calibration are susceptible to standing waves that affect measurements at the plane of the probe microphone due to overlap of incident and reflected waves. These standing-wave effects can be as large as 20 dB, and may affect frequencies both above and below 4 kHz. It has been shown that forwa...

The optimal intensity relation between the two primaries used to generate Distortion Product Otoacoustic Emissions (DPOAEs) in unimpaired human ears, over a clinically relevant intensity range, was evaluated using a commercially available clinical device. The ILO92 was used to determine the level of the DPOAE at 2f1-f2 for 16 combinations of primary levels in the range of 40 to 80 dB SPL from 4...