The next generation of Nucleus(®) fitting: a multiplatform approach towards universal cochlear implant management

Cochlear Implant Remote Assist: Clinical and Real-World Evaluation

OBJECTIVES

To develop and evaluate Cochlear™ Remote Assist (RA), a smartphone-based cochlear implant (CI) teleaudiology solution. The development phase aimed to identify the minimum features needed to remotely address most issues typically experienced by CI recipients. The clinical evaluation phase assessed ease of use, call clarity, system latency, and CI recipient feedback.

DESIGN

The development phase involved mixed methods research with experienced CI clinicians. The clinical evaluation phase involved a prospective single-site clinical study and real-world use across 16 clinics.

STUDY SAMPLE

CI clinicians (N = 23), CI recipients in a clinical study (N = 15 adults) and real-world data (N = 57 CI recipients).

RESULTS

The minimum feature set required for remote programming in RA, combined with sending replacements by post, should enable the clinician to address 80% of the issues typically seen in CI follow-up sessions. Most recipients completed the RA primary tasks without prior training and gave positive ratings for usefulness, ease of use, effectiveness, reliability, and satisfaction on the Telehealth Usability Questionnaire. System latency was reported to be acceptable.

CONCLUSION

RA is designed to help clinicians address a significant proportion of issues typically encountered by CI recipients. Clinical study and real-world evaluation confirm RA's ease of use, call quality, and responsiveness.

Development of Custom Sound® Pro software utilising big data and its clinical evaluation

OBJECTIVES

To inform and optimise a cochlear implant (CI) fitting software design through an analysis of big data to define array-specific comfort (C) level profiles, frequently-used MAP parameters, and the minimum number of Neural Response Telemetry thresholds (tNRT) needed to create an accurate profile. To evaluate the software's ease of use and completion time for AutoNRT®s.

DESIGN

MAPs analysis. Clinical study evaluating software use in creating MAPs, addressing sound-quality issues and setting patient goals.

STUDY SAMPLE

MAPs (N = 39,885); CI recipients (N = 47) and clinicians (N = 19).

RESULTS

Distinct C-level profiles were observed for lateral-wall, contour, and slim-modiolar electrode arrays. Default settings were used for most MAP parameters (13/16) except for Pulse Width, Rate, and Maxima. Nine tNRT measurements were required for an accurate C-level profile. Measurement-time of nine tNRTs via the new algorithm was comparable to five tNRTs using the previous algorithm. Nearly all (99%) clinical tasks were completed by clinicians with the first use of the software. Most CI recipients (79.5%) rated goal-setting as valuable.

CONCLUSION

Custom Sound Pro fitting software developed based on big data analysis incorporates a guided fitting workflow and expected fitting ranges. It helps to improve clinical efficiency, is easy to use and supports patient-centred care.

Optimizing the efficiency of ECAP measurements due to interpolation

BACKGROUND

Thresholds of electrically evoked compound action potentials (TECAP) may serve as starting points for electrophysiologically based fitting of cochlear implants. Absent TECAP data at single electrodes reduces the number of data points available for fitting and can be substituted by interpolation of measured data points.

AIM

To compare complete TECAP profiles with interpolated TECAP profiles of 5/22 (∼22.7%) and 11/22 (50%) electrode contacts.

MATERIAL AND METHODS

Single-centre, retrospective, observational study of data from 624 ears implanted with a Slim Modiolar (CI ×32) or Contour Advance (CI ×12, CI24RE(CA)) electrode array (Cochlear Ltd). The deviation of the complete measured TECAP profile from the same profile with missing and therefore interpolated TECAP values was quantified.

RESULTS

Interpolated TECAP profiles significantly differ from complete measured profiles especially at the basal and apical electrodes. Reference data for Slim Modiolar and Contour Advance electrodes mean profiles are provided.

CONCLUSIONS AND SIGNIFICANCE

Reducing the number of measured TECAP electrodes has to be weighted against losses in the TECAP accuracy of interpolated values. A clinically acceptable compromise may be a reduction from 22 to 11 even non-equidistant data points. While reducing ECAP measurement time, it is accompanied by a minimal loss of accuracy of the TECAP threshold profile.

Comparisons of electrophysiological and psychophysical fitting methods for cochlear implants

OBJECTIVE

This study compared two different versions of an electrophysiology-based software-guided cochlear implant fitting method with a procedure employing standard clinical software. The two versions used electrically evoked compound action potential (ECAP) thresholds for either five or all twenty-two electrodes to determine sound processor stimulation level profiles. Objective and subjective performance results were compared between software-guided and clinical fittings.

DESIGN

Prospective, double-blind, single-subject repeated-measures with permuted ABCA sequences.

STUDY SAMPLE

48 post linguistically deafened adults with ≤15 years of severe-to-profound deafness who were newly unilaterally implanted with a Nucleus device.

RESULTS

Speech recognition in noise and quiet was not significantly different between software- guided and standard methods, but there was a visit/learning-effect. However, the 5-electrode method gave scores on the SSQ speech subscale 0.5 points lower than the standard method. Clinicians judged usability for all methods as acceptable, as did subjects for comfort. Analysis of stimulation levels and ECAP thresholds suggested that the 5-electrode method could be refined.

CONCLUSIONS

Speech recognition was not inferior using either version of the electrophysiology-based software-guided fitting method compared with the standard method. Subject-reported speech perception was slightly inferior with the five-electrode method. Software-guided methods saved about 10 min of clinician's time versus standard fittings.

Psychosocial Impact of the COVID-19 Pandemic on Children With Cochlear Implants and Their Parents/Family Members

Purpose:

The purpose of this study was to describe hearing health care and education experiences of children with cochlear implants (CIs) during the COVID-19 pandemic and the potential psychosocial effects of the pandemic on these children and their parents/family members.

Method:

The study used a cross-sectional survey design. The study sample comprised two groups, namely, parents/family members of children with CIs (study group, n = 70, M age = 44.6 ± 12.4 years) and parents/family members of children with normal hearing (control group, n = 58, M age = 43.8 ± 11.5 years). Parents/family members completed the Perceived Stress Scale (PSS), the Coronavirus Anxiety Scale (CAS), and the Family Perspective Profile form, as well as the Demographic Information form.

Results:

The PSS scores of the study group were higher than those of the control group ( p = .001). However, there was no statistically significant difference between groups in the CAS scores ( p = .896). According to the Family Perspective Profile form, almost half of the parents/family members of children with CIs reported that their children experienced difficulties in education and hearing health care services during the pandemic and showed some changes in their attitudes and behaviors.

Conclusions:

During the pandemic, the stress levels of parents/family members of children with CIs were higher than parents/family members of children with normal hearing. In addition to the challenges posed by the pandemic, the difficulties that parents/family members of children with CIs experience in meeting their children's additional needs related to accessing education and hearing health care services may have contributed to increased stress levels.

Predictive models for cochlear implant outcomes: Performance, generalizability, and the impact of cohort size

While cochlear implants have helped hundreds of thousands of individuals, it remains difficult to predict the extent to which an individual’s hearing will benefit from implantation. Several publications indicate that machine learning may improve predictive accuracy of cochlear implant outcomes compared to classical statistical methods. However, existing studies are limited in terms of model validation and evaluating factors like sample size on predictive performance. We conduct a thorough examination of machine learning approaches to predict word recognition scores (WRS) measured approximately 12 months after implantation in adults with post-lingual hearing loss. This is the largest retrospective study of cochlear implant outcomes to date, evaluating 2,489 cochlear implant recipients from three clinics. We demonstrate that while machine learning models significantly outperform linear models in prediction of WRS, their overall accuracy remains limited (mean absolute error: 17.9-21.8). The models are robust across clinical cohorts, with predictive error increasing by at most 16% when evaluated on a clinic excluded from the training set. We show that predictive improvement is unlikely to be improved by increasing sample size alone, with doubling of sample size estimated to only increasing performance by 3% on the combined dataset. Finally, we demonstrate how the current models could support clinical decision making, highlighting that subsets of individuals can be identified that have a 94% chance of improving WRS by at least 10% points after implantation, which is likely to be clinically meaningful. We discuss several implications of this analysis, focusing on the need to improve and standardize data collection.

A psychoacoustic application for the adjustment of electrical hearing thresholds in cochlear implant patients

Objective

Fitting cochlear implants, especially the precise determination of electrical hearing thresholds, is a time-consuming and complex task for patients as well as audiologists. Aim of the study was to develop a method that enables cochlear implant (CI) patients to determine their electrical hearing thresholds precisely and independently. Applicability and impact of this method on speech perception in noise at soft speech levels were evaluated.

Method

An adaptive psychoacoustic procedure for precise hearing threshold determination (precT) was implemented using MatLab (MathWorks) and a graphical user interface was created. Sound signals were calibrated with a CIC4-Implant-Decoder. Study design: A prospective study including 15 experienced adult cochlear implant users was conducted. Electrical hearing thresholds were determined using the automated precT procedure (auto-precT). Speech perception in noise at 50 dB SPL presentation levels was measured for three conditions: (P1) T-levels kept at the previously established T-levels; (P2) T-levels set to the hearing thresholds determined using auto-precT application; (P3) T-levels set 10 cu below the values determined with auto-precT.

Results

All subjects were able to perform the auto-precT application independently. T-levels were altered on average by an absolute value of 10.5 cu using auto-precT. Median speech reception thresholds were significantly improved from 2.5 dB SNR (P1) to 1.6 dB SNR (P2, p = 0.02). Speech perception was lowest using the globally lowered T-levels, median 2.9 dB SNR (P3, not significant compared to P1 and P2).

Conclusion

The applicability of the developed auto-precT application was confirmed in the present clinical study. Patients benefited from adjusting previously established T-levels to the threshold levels determined by the auto-precT application. The integration of the application in the clinical fitting routine as well as a remote fitting software approach is recommended. Furthermore, future possibilities of auto-precT include the implementation of the application on tablets or smart phones.

Fine-grain recordings of the electrically evoked compound action potential amplitude growth function in cochlear implant recipients

Background

In cochlear implants (CI) measuring the electrically evoked compound action potential (ECAP) has become an important tool for verifying the electrode-nerve interface as well as establishing a basis for a map to program the speech processor. In a standard clinical setup recordings are averaged over 25–100 repetitions to allow for the detection of ECAPs within the noise floor. To obtain an amplitude growth function, these measurements are normally performed for 5–10 different stimulation levels. We evaluate a recording paradigm where the stimulation intensity is increased in quasi-continuous steps and instead of averaging repeated recordings with identical stimulation parameters, running averages over small intervals of stimulation levels are computed. The first visible nerve response was manually identified by two experts.

Results

Both recording paradigms were evaluated in 39 cochlear implants, showing an on average lower threshold of the first nerve response for the quasi-continuous measurement paradigm (Wilcoxon signed-rank test, p = 6.2e−08) compared to the clinical standard paradigm. The mean maximal loudness over all implants and stimulation electrodes was 13% lower at the 80 pulses/s quasi-continuous paradigm compared to the 44 pulses/s clinical standard paradigm.

Conclusions

Beside a more robust determination of the ECAP threshold, the proposed quasi-continuous stimulation paradigm results in a more robust behavioral feedback of the CI user upon the maximal acceptable loudness percept. Furthermore this paradigm can also reveal the fine-structure in the amplitude growth function.

Use of remote control in the intraoperative telemetry of cochlear implant: multicentric study

Introduction

The conventional evaluation of neural telemetry and impedance requires the use of the computer coupled to an interface, with software that provides visualization of the stimulus and response. Recently, a remote control (CR220^®) was launched in the market, that allows the performance of intraoperative tests with minimal instrumentation.

Objective

To evaluate the agreement of the impedance values and neural telemetry thresholds, and the time of performance in the conventional procedure and by the remote control.

Methods

Multicentric prospective cross-sectional study. Intraoperative evaluations of cochlear implants compatible with the use of CR220^® were included. The tests were carried out in the 22 electrodes to compare the time of performance in the two situations. The agreement of the neural telemetry threshold values obtained from five electrodes was analyzed, and the agreement of impedance was evaluated by the number of electrodes with altered values in each procedure.

Results

There were no significant difference between the impedance values. There was a moderate to strong correlation between the electrically-evoked compound action potential thresholds. The mean time to perform the procedures using the CR220 was significantly lower than that with the conventional procedure.

Conclusion

The use of the CR220 provided successful records for impedance telemetry and automatic neural response telemetry.

Self-Adjustment of Upper Electrical Stimulation Levels in CI Programming and the Effect on Auditory Functioning

OBJECTIVES

With current cochlear implants (CIs), CI recipients achieve good speech perception in quiet surroundings. However, in acoustically complex, real-life environments, speech comprehension remains difficult and sound quality often remains poor. It is, therefore, a challenge to program CIs for such environments in a clinic. The CI manufacturer Cochlear Ltd. recently introduced a remote control that enables CI recipients to alter the upper stimulation levels of their user programs themselves. In this concept, called remote assistant fitting (RAF), bass and treble controls can be adjusted by applying a tilt to emphasize either the low- or high-frequency C-levels, respectively. This concept of self-programming may be able to overcome limitations associated with fine-tuning the CI sound processor in a clinic. The aim of this study was to investigate to what extent CI recipients already accustomed to their clinically fitted program would adjust the settings in daily life if able to do so. Additionally, we studied the effects of these changes on auditory functioning in terms of speech intelligibility (in quiet and in noise), noise tolerance, and subjectively perceived speech perception and sound quality.

DESIGN

Twenty-two experienced adult CI recipients (implant use >12 months) participated in this prospective clinical study, which used a within-subject repeated measures design. All participants had phoneme scores of ≥70% at 65 dB SPL in quiet conditions, and all used a Cochlear Nucleus CP810 sound processor. Auditory performance was tested by a speech-in-quiet test, a speech-in-noise test, an acceptable noise level test, and a questionnaire about perceived auditory functioning, that is, a speech and sound quality (SSQ-C) questionnaire. The first session consisted of a baseline test in which the participants used their own CI program and were instructed on how to use RAF. After the first session, participants used RAF for 3 weeks at home. After these 3 weeks, the participants returned to the clinic for auditory functioning tests with their self-adjusted programs and completed the SSQ-C.

RESULTS

Fifteen participants (68%) adjusted their C-level frequency profile by more than 5 clinical levels for at least one electrode. Seven participants preferred a higher contribution of the high frequencies relative to the low frequencies, while five participants preferred more low-frequency stimulation. One-third of the participants adjusted the high and low frequencies equally, while some participants mainly used the overall volume to change their settings. Several parts of the SSQ-C questionnaire scores showed an improvement in perceived auditory functioning after the subjects used RAF. No significant change was found on the auditory functioning tests for speech-in-quiet, speech-in-noise, or acceptable noise level.

CONCLUSIONS

In conclusion, the majority of experienced CI users made modest changes in the settings of their programs in various ways and were able to do so with the RAF. After altering the programs, the participants experienced an improvement in speech perception in quiet environments and improved perceived sound quality without compromising auditory performance. Therefore, it can be concluded that self-adjustment of CI settings is a useful and clinically applicable tool that may help CI recipients to improve perceived sound quality in their daily lives.

Have Cochlear Implant, Won't Have to Travel: Introducing Telemedicine to People Using Cochlear Implants

PURPOSE

This research note describes a planned project to design, implement, and evaluate remote care for adults using cochlear implants and compare their outcomes with those of individuals following the standard care pathway.

METHOD

Sixty people with cochlear implants will be recruited and randomized to either the remote care group or a control group. The remote care group will use new tools for 6 months: remote and self-monitoring, self-adjustment of device, and a personalized online support tool. The main outcome measure is patient empowerment, with secondary outcomes of stability in hearing and quality of life, patient and clinician preference, and use of clinic resources.

CONCLUSION

The clinical trial ends in summer 2016. Remote care may offer a viable method of follow-up for some adults with cochlear implants.

Personalised long-term follow-up of cochlear implant patients using remote care, compared with those on the standard care pathway: study protocol for a feasibility randomised controlled trial

INTRODUCTION

Many resources are required to provide postoperative care to patients who receive a cochlear implant. The implant service commits to lifetime follow-up. The patient commits to regular adjustment and rehabilitation appointments in the first year and annual follow-up appointments thereafter. Offering remote follow-up may result in more stable hearing, reduced patient travel expense, time and disruption, more empowered patients, greater equality in service delivery and more freedom to optimise the allocation of clinic resources.

METHODS AND ANALYSIS

This will be a two-arm feasibility randomised controlled trial (RCT) involving 60 adults using cochlear implants with at least 6 months device experience in a 6-month clinical trial of remote care. This project will design, implement and evaluate a person-centred long-term follow-up pathway for people using cochlear implants offering a triple approach of remote and self-monitoring, self-adjustment of device and a personalised online support tool for home speech recognition testing, information, self-rehabilitation, advice, equipment training and troubleshooting. The main outcome measure is patient activation. Secondary outcomes are stability and quality of hearing, stability of quality of life, clinic resources, patient and clinician experience, and any adverse events associated with remote care. We will examine the acceptability of remote care to service users and clinicians, the willingness of participants to be randomised, and attrition rates. We will estimate numbers required to plan a fully powered RCT.

ETHICS AND DISSEMINATION

Ethical approval was received from North West-Greater Manchester South Research Ethics Committee (15/NW/0860) and the University of Southampton Research Governance Office (ERGO 15329).

RESULTS

Results will be disseminated in the clinical and scientific communities and also to the patient population via peer-reviewed research publications both online and in print, conference and meeting presentations, posters, newsletter articles, website reports and social media.

TRIAL REGISTRATION NUMBER

ISRCTN14644286; Pre-results.

Clinical evaluation of the Nucleus 6 cochlear implant system: performance improvements with SmartSound iQ

Objective:

This paper provides a detailed description of the Nucleus 6 system, and clinically evaluates user performance compared to the previous Nucleus 5 system in cochlear implant recipients. Additionally, it clinically evaluates a range of Nucleus 6 and Nucleus 5 programs to determine the performance benefits provided by new input processing technologies available in SmartSound iQ.

Design

Speech understanding tests were used to clinically validate the default Nucleus 6 program, by comparing performance outcomes against up to five custom Nucleus 5 or Nucleus 6 programs in a range of listening environments. Clinical comparisons between programs were conducted across the following listening environments; quiet, speech weighted noise (co-located and spatially separated noise), and 4-talker babble (co-located and spatially separated noise).

Study sample

Twenty-one adult cochlear implant recipients participated.

Results

Significant speech understanding benefits were found with the default Nucleus 6 program compared to the participants’ preferred program using their Nucleus 5 processor and compared to a range of custom Nucleus 6 programs. All participants successfully accepted and upgraded to the new default Nucleus 6 SmartSound iQ program.

Conclusion

This study demonstrates the acceptance and clinical benefits of the Nucleus 6 cochlear implant system and SmartSound iQ.