Detection of otoacoustic emissions in chinchilla when the middle ear contains amniotic fluid

Abstract

Both human amniotic fluid and saline in the chinchilla middle ear resulted in changes in otoacoustic-emission detection patterns and WBR that may be relevant to newborn hearing screening.

Factors affecting sound energy absorbance in acute otitis media model of chinchilla

“…1 for ER) at frequencies below 1 kHz. In the publication by Akinpelu et al (2015), the EA of normal chinchillas ranged from 0.2–0.4 (0.6–0.8 for ER) at f < 1 kHz. In our present study, the ambient EA of control ears at low frequencies ranged from 0.4–0.8, much larger values than those in the other studies.…”

“…These investigators also reported the ER in neonatal and adult chinchillas (Hsu et al 2001). Akinpelu et al (2015) compared ambient ER of normal chinchillas with those injected with middle ear fluid. In the present study, the pattern of our EA tympanograms in uninfected normal ears is consistent with those reported by Margolis et al (2001) and Hsu et al (2001).…”

“…However, there are differences in the baseline measurements of ambient ER or EA between our present study and previous studies. To establish a better comparison, we extracted and converted ER into the ambient EA of normal ears from the data of Margolis et al (2001) and Akinpelu et al (2015). Then we plotted these data together with our control EA values.…”

“…For example, use of larger values of ear-canal area decreases EA at low frequencies (Voss et al 2008). The area used to calculate the ER in Akinpelu et al (2015) was not reported. A constant area with diameter of 8 mm was used by Margolis et al (2001).…”

“…2 in their paper) suggested that the MEP existed in some animals in their studies. In the study by Akinpelu et al (2015), a distortion product otoacoustic emission measurement, which was time-consuming, preceded the ER measurement. Negative MEP could be produced during the otoacoustic emission measurement and affect the control ER results.…”