Objective: This study outlines a series of experiments using the neural response telemetry (NRT) system Nucleus CI24M cochlear implant to measure electrically evoked compound action potential (EAP). The goal this investigation was develop protocol that allows successful recording EAP in majority users. Design: Twenty-six postlingually deafened adults participated study. A were conducted allowed us examine how manipulation stimulation and parameters may affect morphology recorded NRT system....

This study describes a method for recording the electrically evoked, whole-nerve action potential (EAP) in users of Ineraid cochlear implant. The is an adaptation one originally used by Charlet de Sauvage et al. [J. Acoust. Soc. Am. 73, 615-627 (1983)] guinea pigs. response, recorded from 11 subjects, consists single negative peak that occurs with latency approximately 0.4 ms. EAP input/output functions are steeply sloping and monotonic. Response amplitudes ranging up to 160 micro V have...

Objective: The objective of this study was to determine the relationship between electrically evoked whole nerve action potential (EAP) and electrical auditory brain stem response (EABR) thresholds MAP threshold (T-level) maximum comfort level (C-level) for subjects who use Nucleus 24 cochlear implant system. Design: Forty-four adult users participated in study. EAP were recorded using Neural Response Telemetry System developed by Cochlear Corporation. EABR measured a subset 14 standard...

Objective The primary goal of this study was to examine changes that may occur in electrode impedance, electrically evoked compound action potential (EAP) threshold and slope the EAP growth function, behavioral measures (MAP T-level) maximum comfort (C-level) over time both adult child cochlear implant users. Secondary goals were determine whether these are consistent between children adults, T- C-levels) electrophysiologic (EAP thresholds) exhibit same trends time. Design Thirty-five 33...

The audiologic performance of 54 postlingually deafened adults wearing cochlear implants was uniformly evaluated. participants had 9 months' or more experience with one five different prostheses (Los Angeles Single Channel (N = 11), Vienna 4), Melbourne Multichannel 18), Utah 19), San Francisco 2). multichannel designs enabled to recognize environmental sounds, provided speech reading enhancement, and most users understand limited in the sound-only condition, compared single-channel implant group.

The purpose of this study is to examine the relationship between electrically evoked compound action potential (EAP) thresholds and MAP (T-levels) maximum comfort levels (C-levels) in children implanted with Nucleus 24 device.EAP were measured using Neural Response Telemetry system device. Twenty cochlear implant participated study. EAP compared behavioral measures T- C-level used construct these on a daily basis. For subjects, both C-levels obtained same visit, which occurred at 3 5 mo...

To assess the audiologic and surgical outcomes for pediatric cochlear implant patients with inner ear malformations.Retrospective review of 315 cases from 1994 to 2002.Twenty-eight known malformations determined on high-resolution computed tomography (HRCT) temporal bone were subjects review. Results HRCT findings, intraoperative postoperative complications, objective measures both closed- open-set testing speech perception analyzed.Patients constellation an incompletely partitioned (IP)...

Objective To evaluate the binaural listening advantages for speech in quiet and noise to localize sound when independently programmed cochlear implants are used, determine whether ears with different hearing ability duration of profound deafness perform differently as well what extent preimplant psychophysical physiologic assessment could be predictive performance. Study Design Prospective study which patients were prospectively selected undergo bilateral implantation during a single...

One likely determinant of performance with a cochlear implant is the degree interaction that occurs when overlapping subsets nerve fibers are stimulated by various electrodes multielectrode array. The electrically evoked compound action potential (ECAP) can be used to assess physiological channel interaction. This paper describes results from two different methods analysis ECAP measures made Nucleus neural response telemetry system. Using forward-masking stimulus paradigm, masker and probe...

Objective: Recording a compound action potential in response to electrical stimulation requires attention minimize contamination due stimulus artifact. In patients implanted with the Nucleus® 24 device, electrically evoked whole-nerve (EAP) is recorded using neural telemetry (NRT) system. This system employs forward-masking technique that greatly reduces However, theoretical considerations and experimental animal data suggest may distort acquired EAP waveform under some situations. We...

Auditory neuropathy, characterized by absence or abnormality of auditory brainstem responses and normal otoacoustic emissions, is often associated with particularly poor response to amplification. Outcome data from four such pediatric patients who received cochlear implants are discussed.Four the Carolina Children's Communicative Disorders Program were identified as having a diagnosis neuropathy before implantation Clarion implant. Speech collected after compared control implant patients,...

Electrically evoked auditory brain stem responses (EABR) were measured in 12 adults and 14 children with the Nucleus cochlear implant. Measures made both intra operatively several months following surgery. EABR thresholds consistently greater than clinically determined measures of behavioral threshold (T-level) but less maximum comfort levels (C-level). When data pooled across subjects different stimulating electrodes, strongly correlated T- C-levels. In where intraoperative postimplant...

Electrically evoked whole nerve action potentials (EAP) have been recorded from 20 Ineraid cochlear implant users in response to bipolar and/or monopolar electrical stimulation of the cochlea. EAP growth functions and refractory recovery were obtained for a variety different stimulating conditions. Where possible, parallel psychophysical experiments conducted that measured just detectable increment stimulus current level (JND), forward-masking functions, detection thresholds range stimuli....

In Brief Objective: The purpose of this study was to evaluate the accuracy with which auditory steady-state response (ASSR) and tone burst brain stem (ABR) thresholds predict behavioral thresholds, using a within-subjects design. Because spectra stimuli used evoke ABR ASSR differ, it hypothesized that predictive also would particularly in subjects steeply sloping hearing losses. Design: were recorded group 14 adults normal hearing, 10 flat, sensorineural losses, sloping, high-frequency,...