Reliability of distortion-product otoacoustic emissions in the common marmoset (Callithrix jacchus)

Abstract

This study examines the test-retest reliability of distortion-product otoacoustic emissions (DPOAEs) in ketamine-anesthetized common marmosets (Callithrix jacchus). DPOAE gain functions were measured at 16 f2-frequencies between 3 – 24 kHz. Test-retest reliability was assessed at the following time intervals: 1) Interleaved, in which two gain functions were obtained at each frequency before advancing to the next frequency, 2) Immediate, wherein one gain function was collected at all f2-frequencies and the retest was immediately performed without removing the probe tip, 3) Short-term, in which the retest followed a 10-min period with the probe removed, and 4) Long-term, wherein the retest was performed at least one week after the initial test. Reliability was assessed using four correlation coefficients used in the literature. Test-retest reliability was best in the interleaved interval and worst in the short-term interval. In general, reliability was best when primary-tone levels were high. Correlation coefficients decreased at frequencies above 12-kHz in the short-term and long-term intervals, but the decrease was more substantial in females than in males in the long-term interval. At frequencies below 12 kHz, same-day measurements (2, 3) were less repeatable, regardless of whether the probe was removed, which may be due to time under anesthesia. These results have implications for DPOAE studies where repeated measures are required and when treatment or group differences are small.

Neural presbycusis at ultra-high frequency in aged common marmosets and rhesus monkeys

“…DPOAE, which has been rarely tested in monkeys [ 38 , 39 , 50 ], was stable with age, indicating that OHCs did not deteriorate in geriatric NHPs. Because the microphone output of 20 dB was not amplified, our DPOAE thresholds were higher than previously reported [ 42 ]. Histologic results also showed that neural degeneration occurred prior to HC degeneration in NHPs.…”

“…DPOAEs are responses generated when the cochlea is stimulated simultaneously by two pure tone frequencies, which are similar in rhesus monkeys and humans [ 38 – 40 ]. To our knowledge, only two previous studies assessed DPOAEs in marmosets, finding that DPOAEs tended to be slightly stronger in the right than in the left ear [ 41 , 42 ]. Neither of these studies, however, analyzed the associations between DPOAE and age in marmosets.…”

Stimulus frequency otoacoustic emissions evoked by swept tones

“…Without good reliability, any changes in the swept-tone SFOAEs cannot be considered as evidences of cochlear functional changes instead of measurement errors (Franklin et al, 1992;Zhao and Stephens, 1999). Many studies have been conducted to investigate the reliability of the DPOAEs (Parazzini et al, 2006a,b;Valero and Ratnam, 2011;Wagner et al, 2008;Zhao and Stephens, 1999) and TEOAEs (Franklin et al, 1992;Keppler et al, 2010;Marshall and Heller, 1996), but the reliability of SFOAEs was rarely explored. In this study, the reliability of swept-tone SFOAEs was assessed under various stimulus conditions in 10 subjects with normal hearings.…”

Influence of Ketamine–Xylazine Anaesthesia on Cubic and Quadratic High-Frequency Distortion-Product Otoacoustic Emissions

“…Cederholm et al 2012). Hence, the reliability of DPOAE data obtained at low stimulus levels is an issue to be considered (Valero and Ratnam 2011). Ketamine is a widely used anaesthetic and analgesic which also acts as an N-methyl-D-aspartate receptor antagonist (NMDA antagonist).…”