Neural response imaging (NRI) cochlear mapping: prospects for clinical application

Arnold, Laure; Lindsey, Philip; Hacking, C.; Boyle, P.

doi:10.1179/cim.2007.8.4.173

Cited by 3 publications

(3 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Advanced Bionics CI system uses the neural response imaging technique to record eCAPs (36), as described in previous work (1). In summary, a 32-μs per phase biphasic current pulse is delivered between an intracochlear and the case ground electrodes.…”

Section: Electrically Evoked Compound Action Potentialmentioning

confidence: 99%

Self-Assessment of Cochlear Health by New Cochlear Implant Recipients: Daily Impedance, Electrically Evoked Compound Action Potential and Electrocochleography Measurements Over the First Three Postoperative Months

Mushtaq,

Soulby,

Boyle

et al. 2024

Otol Neurotol

View full text Add to dashboard Cite

Hypotheses In newly implanted cochlear implant (CI) users, electrically evoked compound action (eCAPs) and electrocochleography (ECochGs) will remain stable over time. Electrode impedances will increase immediately postimplantation due to the initial inflammatory response, before decreasing after CI switch-on and stabilizing thereafter. Background The study of cochlear health (CH) has several applications, including explaining variation in CI outcomes, informing CI programming strategies, and evaluating the safety and efficacy of novel biological treatments for hearing loss. Very early postoperative CH patterns have not previously been intensively explored through longitudinal daily testing. Thanks to technological advances, electrode impedances, eCAPs, and ECochGs can be independently performed by CI users at home to monitor CH over time. Methods A group of newly implanted CI users performed daily impedances, eCAPs, and ECochGs for 3 months at home, starting from the first day postsurgery (N = 7) using the Active Insertion Monitoring system by Advanced Bionics. Results Measurement validity of 93.5, 93.0, and 81.6% for impedances, eCAPs, and ECochGs, respectively, revealed high participant compliance. Impedances increased postsurgery before dropping and stabilizing after switch-on. eCAPs showed good stability, though statistical analyses revealed a very small but significant increase in thresholds over time. Most ECochG thresholds did not reach the liberal signal-to-noise criterion of 2:1, with low threshold stability over time. Conclusion Newly implanted CI recipients can confidently and successfully perform CH recordings at home, highlighting the valuable role of patients in longitudinal data collection. Electrode impedances and eCAPs are promising objective measurements for evaluating CH in newly implanted CI users.

show abstract

Section: Electrically Evoked Compound Action Potentialmentioning

confidence: 99%

Self-Assessment of Cochlear Health by New Cochlear Implant Recipients: Daily Impedance, Electrically Evoked Compound Action Potential and Electrocochleography Measurements Over the First Three Postoperative Months

Mushtaq,

Soulby,

Boyle

et al. 2024

Otol Neurotol

View full text Add to dashboard Cite

show abstract

“…Neural Response Imaging is the technique used to record eCAPs via the Advanced Bionics CI system (16). In order to record an eCAP threshold, current is delivered between one intra-cochlear electrode contact and the case ground electrode.…”

Section: Ecapsmentioning

confidence: 99%

“…The eCAP is a direct measurement of a synchronized neural response generated by auditory nerve fibers that makes it feasible to evaluate the health status of the auditory nerve (9,16). It is sensitive to electrode impedances, electrode placement and the health status of auditory nerve fibers near the recording electrode (17,18).…”

Section: Introductionmentioning

confidence: 99%

Self-assessment of cochlear health by cochlear implant recipients

et al. 2022

View full text Add to dashboard Cite

Recent technological advances in cochlear implant (CI) telemetry have enabled, for the first time, CI users to perform cochlear health (CH) measurements through self-assessment for prolonged periods of time. This is important to better understand the influence of CH on CI outcomes, and to assess the safety and efficacy of future novel treatments for deafness that will be administered as adjunctive therapies to cochlear implantation. We evaluated the feasibility of using a CI to assess CH and examined patterns of electrode impedances, electrically-evoked compound action potentials (eCAPs) and electrocochleography (ECochGs), over time, in a group of adult CI recipients. Fifteen subjects were trained to use the Active Insertion Monitoring tablet by Advanced Bionics, at home for 12 weeks to independently record impedances twice daily, eCAPs once weekly and ECochGs daily in the first week, and weekly thereafter. Participants also completed behavioral hearing and speech assessments. Group level measurement compliance was 98.9% for impedances, 100% for eCAPs and 99.6% for ECochGs. Electrode impedances remained stable over time, with only minimal variation observed. Morning impedances were significantly higher than evening measurements, and impedances increased toward the base of the cochlea. eCAP thresholds were also highly repeatable, with all subjects showing 100% measurement consistency at, at least one electrode. Just over half of all subjects showed consistently absent thresholds at one or more electrodes, potentially suggesting the existence of cochlear dead regions. All subjects met UK NICE guidelines for cochlear implantation, so were expected to have little residual hearing. ECochG thresholds were, unsurprisingly, highly erratic and did not correlate with audiometric thresholds, though lower ECochG thresholds showed more repeatability over time than higher thresholds. We conclude that it is feasible for CI users to independently record CH measurements using their CI, and electrode impedances and eCAPs are promising measurements for objectively assessing CH.

show abstract

Cochlear implantees: Analysis of behavioral and objective measures for a clinical population of various age groups

Greisiger¹,

Shallop

Hol³

et al. 2015

Cochlear Implants International

View full text Add to dashboard Cite

Analyzing initial and follow-up mapping levels from previous patients is very important for a CI Center in terms of quality control. The mean T/C-levels reported in this study can provide guidance to our programming audiologists and help them determine the initial programming levels to be stored in the speech processor, especially for very young patients. Unfortunately intra-operative objective measures in our study, such as ECAP, ESRT, and electrode impedances did not provide statistically significant correlations that may help to predict the programming T- and C-levels for all patients. However, we have observed cases where the intra-operative objective measures of ESRT and TECAP profiles were very similar to an individual's MAP profile. It was not possible, however, to determine why some patients did not have an objective measures profile that was similar to their programming levels profile.

show abstract

Neural response imaging (NRI) cochlear mapping: prospects for clinical application

Cited by 3 publications

References 21 publications

Self-Assessment of Cochlear Health by New Cochlear Implant Recipients: Daily Impedance, Electrically Evoked Compound Action Potential and Electrocochleography Measurements Over the First Three Postoperative Months

Self-Assessment of Cochlear Health by New Cochlear Implant Recipients: Daily Impedance, Electrically Evoked Compound Action Potential and Electrocochleography Measurements Over the First Three Postoperative Months

Self-assessment of cochlear health by cochlear implant recipients

Cochlear implantees: Analysis of behavioral and objective measures for a clinical population of various age groups

Contact Info

Product

Resources

About