Combining Intraoperative Electrocochleography with Robotics-Assisted Electrode Array Insertion.

Objective: To describe the use of robotics-assisted electrode array (EA) insertion combined with intraoperative electrocochleography (ECochG) in hearing preservation cochlear implant surgery.

Study Design: Prospective, single-arm, open-label study.

Setting: All procedures and data collection were performed at a single tertiary referral center.

Evaluation of Real-Time Intracochlear Electrocochleography for Guiding Cochlear Implant Electrode Array Position.

This study evaluates intracochlear electrocochleography (ECochG) for real-time monitoring during cochlear implantation. One aim tested whether adjusting the recording electrode site would help differentiate between atraumatic and traumatic ECochG amplitude decrements. A second aim assessed whether associations between ECochG amplitude decrements and post-operative hearing loss were weaker when considering hearing sensitivity at the ECochG stimulus frequency compared to a broader frequency range.

Longitudinal Electrocochleography as an Objective Measure of Serial Behavioral Audiometry in Electro-Acoustic Stimulation Patients.

Objective: Minimally traumatic surgical techniques and advances in cochlear implant (CI) electrode array designs have allowed acoustic hearing present in a CI candidate prior to surgery to be preserved postoperatively. As a result, these patients benefit from combined electric-acoustic stimulation (EAS) postoperatively. However, 30% to 40% of EAS CI users experience a partial loss of hearing up to 30 dB after surgery.

Neural Correlates of Vocal Auditory Feedback Processing: Unique Insights from Electrocorticography Recordings in a Human Cochlear Implant User.

There is considerable interest in understanding cortical processing and the function of top-down and bottom-up human neural circuits that control speech production. Research efforts to investigate these circuits are aided by analysis of spectro-temporal response characteristics of neural activity recorded by electrocorticography (ECoG). Further, cortical processing may be altered in the case of hearing-impaired cochlear implant (CI) users, as electric excitation of the auditory nerve creates a markedly different neural code for speech compared with that of the functionally intact hearing system.

Successful Hearing Preservation After Reimplantation of a Failed Hybrid Cochlear Implant.

Objective: The purpose of this case study was to demonstrate hearing preservation of a subject who was implanted with a 10-mm short electrode cochlear implant that was determined to be malfunctioning at 6 months postimplantation and was explanted and reimplanted with a 16-mm short electrode device.Study Design: Single-subject case study.Setting: Research hospital.

Hearing Loss After Activation of Hearing Preservation Cochlear Implants Might Be Related to Afferent Cochlear Innervation Injury.

Objective: Characterize hearing loss (HL) after hearing preservation cochlear implantation and determine the association between high charge electrical stimulation (ES) and late loss of acoustic hearing.

Methods: A retrospective cohort analysis of all hearing preservation implantees at our center (n = 42) assayed HL as a function of maximum charge. We analyzed serial audiometry from 85 patients enrolled in the multicenter Hybrid S8 trial to detail the hearing loss greater than 1 month after implantation.

Direct recordings from the auditory cortex in a cochlear implant user.

Electrical stimulation of the auditory nerve with a cochlear implant (CI) is the method of choice for treatment of severe-to-profound hearing loss. Understanding how the human auditory cortex responds to CI stimulation is important for advances in stimulation paradigms and rehabilitation strategies. In this study, auditory cortical responses to CI stimulation were recorded intracranially in a neurosurgical patient to examine directly the functional organization of the auditory cortex and compare the findings with those obtained in normal-hearing subjects.

Relationships between electrically evoked potentials and loudness growth in bilateral cochlear implant users.

Objectives: The goals of this study were (1) to describe the relationship between electrically evoked compound action potential (ECAP) and electrically evoked auditory brainstem response (EABR) amplitude growth functions and loudness growth functions in bilateral cochlear implant (CI) users, and (2) to determine whether matching the stimulus levels in the two ears of bilateral CI users based on equal ECAP amplitude, EABR amplitude, or current level resulted in the smallest discrepancy in loudness rating across the two ears.

Design: Ten adult, bilateral CI users participated in this study. The stimulus used to elicit loudness judgments and generate ECAP and EABR growth functions was a train of biphasic current pulses (32 μs/phase) presented at a rate of 23 pps.

The relationship between electrically evoked compound action potential and speech perception: a study in cochlear implant users with short electrode array.

Objectives: To determine the extent to which electrically evoked compound action potential (ECAP) measurements were related with speech perception performance in implant users with a short electrode array and to investigate the relationship between ECAP measures and performance according to specific devices.

Design: Prospective study.

Setting: Tertiary referral center.

Comparison of electrically evoked compound action potential thresholds and loudness estimates for the stimuli used to program the Advanced Bionics cochlear implant.

Background: In the mid-1990s, Cochlear Corporation introduced a cochlear implant (CI) to the market that was equipped with hardware that made it possible to record electrically evoked compound action potentials (ECAPs) from CI users of all ages. Over the course of the next decade, many studies were published that compared ECAP thresholds with levels used to program the speech processor of the Nucleus CI. In 2001 Advanced Bionics Corporation introduced the Clarion CII cochlear implant (the Clarion CII internal device is also known as the CII Bionic Ear).

The effect of changes in stimulus level on electrically evoked cortical auditory potentials.

Objectives: The purpose of this study was to determine whether the electrically evoked acoustic change complex (EACC) could be used to assess sensitivity to changes in stimulus level in cochlear implant (CI) recipients and to investigate the relationship between EACC amplitude and rate of growth of the N1-P2 onset response with increases in stimulus level.

Design: Twelve postlingually deafened adults using Nucleus CI24 CIs participated in this study. Nucleus Implant Communicator (NIC) routines were used to bypass the speech processor and to control the stimulation of the implant directly.

The electrically evoked auditory change complex: preliminary results from nucleus cochlear implant users.

Objectives: The purpose of this study was to determine if changes in the position of the stimulating electrode in the cochlea could be used to elicit the electrically evoked auditory change complex (EACC) from Nucleus cochlear implant users.

Design: Nine postlingually deafened adults participated in this study. Each study participant had been using his or her Nucleus CI24 cochlear implant for at least 3 mos before testing.