Effect of hearing loss in electrocochleographic investigation of endolymphatic hydrops using tone-pip and click stimuli

Abstract

Extratympanic electrocochleography (ECochG) was performed on 37 patients referred to the Evoked Potential Clinic with suspected Ménière's disease. The patients were classified according to their hearing impairment and audiometric configuration. Click and tone-pip stimuli with tone frequencies of 1 and 4 kHz were presented at a rate of 10 per second. Amplitude, latency and general waveform characteristics of the summation potential (SP) and action potential (AP) were analysed for each averaged response with respect to the level and configuration of the hearing loss. The highest incidence of abnormal percentage SP was in patients with average hearing loss in the range of 40–64 dB HL using the click stimulus. In low tone hearing loss, hydrops was identified from an enhanced SP in significantly more patients using the click and 4 kHz tone-pip than the 1 kHz stimulus. Measurement of the width of the 1 kHz tone-pip response waveform was abnormal in some patients even though the click and 4 kHz responses were normal. The optimum stimulus for identification of hydrops from an enhanced SP is dependent on the level and configuration of the hearing loss.

A Diagnostic Test for Ménière's Disease and Cochlear Hydrops: Impaired High-Pass Noise Masking of Auditory Brainstem Responses

“…Unfortunately, a number of variables can significantly affect the results and diagnostic value of the SP, as well as the SP/AP ratio measures; in particular, hearing loss (8,17).…”

Cochlear Potentials in Clinical Audiology

“…Traditionally, it has been more com mon to use toneburst stimuli for TT record ings only. Recently, however, tonebursts have [17] 110 dBSPL TM Mean -0.27 SD 0.17 Margolis et al [9] 110 dB SPL TM Mean -0.66 -0.96 SD 0.52 0.77 been applied in several TM studies [9,11,17,20,21 ]. One advantage of using tonebursts in addition to clicks is that a higher degree of response frequency specificity can be achieved.…”

“…The decision to use a certain criteri on value is further complicated by the fact that the rate of detection of MD based on an enhanced SP depends on the degree of hearing loss. Koyuncu et al [11], for example, found a greater incidence of abnormal SP amplitudes for patients with an average hearing loss in the range of 40-60 dB HL than for those with a Audiol Ncuroatol 1997;2:241-256hearing loss greater than 65 dB HL or between 0 and 39 dB HL. Gibson [33] suggested lower ing the criterion value for subjects with marked hearing loss to reduce the incidence of false-positive and false-negative results.…”

Elektrophysiologische Diagnostik bei Tieftonschwerhörigkeit: Klinische und prognostische Aspekte

“…Bei deren Mitbeteiligung verlän-gert sich die Laufzeit der Wanderwelle, bis sie intakte Haarzellen antrifft, und damit auch die CAP-Latenz. So ist die CAP-Latenz bei Innenohrschwerhörigkeit mit zunehmender Hörminderung verlängert [27], ebenso beim M. Menire bei pantonalem Hörverlust und geringer Fluktuation [14]. Ein weiter CAP-Komplex weist auf eine Desynchronisation der neuralen Einzelfaserantworten hin und wird häufig beim Akustikusneurinom [28], aber auch beim fortgeschrittenen M. Menire beobachtet [29].…”

“…Ein weiter CAP-Komplex weist auf eine Desynchronisation der neuralen Einzelfaserantworten hin und wird häufig beim Akustikusneurinom [28], aber auch beim fortgeschrittenen M. Menire beobachtet [29]. Die CAP-Weite korreliert bei Menire-Patienten signifikant mit dem Ausmaû des Hörverlustes [27]. Heruntergeladen von: University of Florida.…”