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Hearing Aids for the Pediatric Population
Published in Stavros Hatzopoulos, Andrea Ciorba, Mark Krumm, Advances in Audiology and Hearing Science, 2020
Katia de Almeida, Maria Cecíli Martinelli
Otoacoustic emissions provide a physiologic means of assessing preneural auditory function (Gorga et al., 1993; Kemp et al., 1990). The presence of OAEs is consistent with normal or near-normal hearing thresholds in a given frequency region. Although performing OAEs in children with a hearing loss already diagnosed by electrophysiological evaluation seems redundant, it is important to determine the location of the lesion. Used in conjunction with ABR, OAEs are not only useful in the differential diagnosis of cochlear hearing loss but also in the identification of children with neurological dysfunction (ASHA, 2004).
Cochlear mechanisms and processes
Published in Stanley A. Gelfand, Hearing, 2017
Landmark work by Kemp (1978, 1979) demonstrated that the cochlea can produce sounds as well as receive them. He found that when a click is directed into the ear, it is followed by an echo emitted back from the cochlea. This emission can be detected by a probe microphone located in the ear canal at latencies in the vicinity of approximately 5 to 15 ms following the click. The phenomenon was originally referred to as the Kemp echo, but is now known as the transient- or click-evoked otoacoustic emission. Otoacoustic emissions can also be evoked by tone bursts, individual pure tones, pairs of pure tones, and also are produced spontaneously by the ear without any sound stimulus.
The neonate
Published in Louise C Kenny, Jenny E Myers, Obstetrics, 2017
Some cases of permanent hearing loss can be detected in the newborn period and this allows early provision for the child and family. In high-income settings screening should be done with objective tests. In the UK newborn hearing screening is conducted with otoacoustic emissions. This procedure involves playing clicks to the baby. A healthy cochlea responds by making noises that can be detected. Screen failure or an uncertain response leads to an automated auditory brainstem response (AABR) test. In income-constrained settings questionnaires or behavioural testing can be used in a targeted or unselected way, but need to be piloted and linked to educational and other support.
Cochlear implantation in neurobrucellosis: Two case reports
Published in Acta Oto-Laryngologica Case Reports, 2022
Afrah Alshalan, Medhat Yousef, Abdulrahman Alsanosi
Ten years later she presented to our hospital for hearing rehabilitation. The first pure tone audiogram (PTA) showed bilateral severe sensorineural hearing loss (SNHL). Speech Reception Threshold (SRT) was 85 dB HL and 75 dB HL for right and left ears respectively. Word recognition Score (WRS) was 24% and 32% for right and left ears respectively. Tympanogram was normal and there were no stapedius muscle reflexes on both sides. Transient evoked otoacoustic emissions were absent bilaterally. There was no benefit of using hearing aids for 6 months. Aided WRS in quite (at 65 dB HL) was 24% and 28% for right and left ears respectively. She was then referred to the cochlear implant committee in our tertiary Center as a potential candidate for cochlear implantion. Computed tomography (CT) and magnetic resonance imaging (MRI) scans showed patent and normally formed cochlea without any sign of labyrinthitis ossificans (Figure 1). After complete evaluation of cochlear implant committee, she was accepted for unilateral cochlear implant. In October 2018, she underwent CI in the right ear with Advanced Bionics HiFocus™ Mid-Scala electrode. During surgery, the electrode array was fully inserted. Impedance filed telemetry (IFT) was performed and reflected normal impedance levels at all electrodes. Electrically Evoked Compound Action Potentials (ECAP) were successfully recorded.
A clinical comparison of DPOAE fine structure reduction methods
Published in International Journal of Audiology, 2021
Steven C. Marcrum, Eva Höfle, Erin M. Picou, Thomas Steffens, Peter Kummer, Pingling Kwok
Otoacoustic emission amplitude is determined by the complex interaction of technical factors related to both stimulus presentation and response processing with the physiological properties of a given ear. While relatively stable in both children (Konrad-Martin et al. 2020; Sockalingam et al. 2007) and adults (Marcrum et al. 2016; Beattie, Kenworthy, and Luna 2003; Reavis et al. 2015) in response to repeated stimulation, OAE amplitude has been shown to vary significantly according to stimulus calibration method (Scheperle et al. 2008; Reuven et al. 2013; Neely and Gorga 1998), absolute stimulus levels and level relationships (Marcrum et al. 2016; Johnson et al. 2006a; Kummer, Janssen, and Arnold 1998; Whitehead et al. 1995b), stimulus frequency (Gorga et al. 1993; Akinpelu, Funnell, and Daniel 2019; Gorga et al. 1997), outer and middle ear mechano-acoustics (Gehr et al. 2004; Job and Nottet 2002; Lonsbury-Martin et al. 1994; Owens et al. 1993; Marcrum, Kummer, and Steffens 2017; Janssen et al. 2005), and hearing threshold (Norton et al. 2000; Gorga et al. 1997; Gorga et al. 1996; Blankenship et al. 2018). Results of the present study suggest that, while the existence of fine structure constitutes a further source of variability in DPOAE amplitude, its potential impact can be reduced through the manipulation of stimulus characteristics in real time.
Lack of association between contralateral inhibition of otoacoustic emissions and vowel formant discrimination in noise
Published in Hearing, Balance and Communication, 2020
Ian B. Mertes, Kristin M. Johnson
The MOC reflex is activated by both steady-state and fluctuating noises [3,4], suggesting that it contributes to listening in daily noisy situations. The MOC reflex can be measured using a contralateral inhibition paradigm in which the change in otoacoustic emission (OAE) amplitude is quantified without versus with a contralateral MOC activator [5]. Otoacoustic emissions are soft sounds generated as a byproduct of outer hair cell amplification of sound [6] and are influenced by activity of the MOC reflex. Contralateral inhibition measurements may be clinically useful for assessing the source of auditory difficulties for a variety of conditions including auditory neuropathy spectrum disorder [7], auditory processing disorder [8], hearing difficulties despite a normal audiogram [9], myasthenia gravis [10], and smoking [11]. A review of the potential clinical utility of contralateral inhibition testing can be found in Murdin and Davies [12].