Cochlear implant systems that combine electric and acoustic stimulation in the same ear are now commercially available and the number of patients using these devices is steadily increasing. In particular, electric-acoustic stimulation is an option for patients with severe, high frequency sensorineural hearing impairment. There have been a range of approaches to combining electric stimulation and acoustic hearing in the same ear. To develop a better understanding of fitting practices for devices that combine electric and acoustic stimulation, we conducted a systematic review addressing three clinical questions: what is the range of acoustic hearing in the implanted ear that can be effectively preserved for an electric-acoustic fitting?; what benefits are provided by combining acoustic stimulation with electric stimulation?; and what clinical fitting practices have been developed for devices that combine electric and acoustic stimulation? A search of the literature was conducted and 27 articles that met the strict evaluation criteria adopted for the review were identified for detailed analysis. The range of auditory thresholds in the implanted ear that can be successfully used for an electric-acoustic application is quite broad. The effectiveness of combined electric and acoustic stimulation as compared with electric stimulation alone was consistently demonstrated, highlighting the potential value of preservation and utilization of low frequency hearing in the implanted ear. However, clinical procedures for best fitting of electric-acoustic devices were varied. This clearly identified a need for further investigation of fitting procedures aimed at maximizing outcomes for recipients of electric-acoustic devices.

Related to the hearing health journey, this study aimed to: (i) explore how empowerment manifests itself from individuals’ first awareness of hearing loss through to hearing aid fitting and then to...

Objective: We investigated effects of aetiology and age at implantation on changes in threshold (T) levels, comfortable (C) levels and dynamic range (DR) for cochlear implants (CIs) in children over the first five years of life. Design: Information was collected at 6 months post-activation of CIs, and at 3 and 5 years of age. Study sample: One hundred and sixty-one children participating in the Longitudinal Outcomes of Children with Hearing Impairment (LOCHI) study. Results: Children with neural and structural cochlear lesions had higher T-levels and C-levels as compared to those without these conditions. Parameter settings varied from manufacturer’s defaults more often in the former than in the latter group. Investigation of the effect of age at implantation for children without neural and structural cochlear lesions showed that those implanted at ≤12 months of age had higher T-levels and narrower DR at 6 months post-activation, as compared to the later-implanted group. For both early- and later-implanted groups, the C-levels at 6 months post-activation were lower than those at age 3 and 5 years. There were no significant differences in T-levels, C-levels, or DR between age 3 and 5 years. Conclusions: Aetiology and age at implantation had significant effects on T-levels and C-levels.

Many adults who receive a cochlear implant in one ear have usable residual hearing in the opposite ear. The simultaneous use of a cochlear implant (CI) and a hearing aid (HA) in the contralateral ear, or bimodal fitting, provides the recipient with potentially complementary information to the auditory system for speech perception, localization, and functional benefits in everyday life via two different modes of stimulation (acoustic and electric). This study investigated consonant perception in listeners who use bimodal fitting with the aim to identify the acoustic cues responsible for speech understanding when an HA is used together with a CI in comparison with the use of a CI alone. The results showed that on average, there was significant improvement in consonant recognition in quiet and in noise when adults wore CIs with HAs compared with CIs alone. Feature analysis of consonants was performed to directly examine what additional cues were provided by the HA to enhance consonant perception. This analysis showed that on average, there was a significant increase in reception of information about voicing in quiet conditions and about voicing and manner of articulation in noise. There was no difference in the transmission of information about place of articulation. The implications of these findings on rehabilitation of adults with unilateral CI are discussed.

Background: Many older Australian adults with cochlear implants (CI) lack funding for replacement sound processors, risking complete device failure and reduced quality of life. The need for replacement CI devices for individuals with obsolete sound processors and no access to funding poses an increasing public health challenge in Australia and worldwide. We aimed to investigate the clinical and cost-effectiveness of upgrading obsolete CI sound processors in older adults. Methods: Alongside an Australian Government-funded upgrade program, a prospective, mixed-methodology design study was undertaken. Participants were aged 65 and over, with obsolete Cochlear™ sound processors and no funding for replacements. This study compared speech perception in noise, as well as self-reported outcome measures, including cognition, listening effort, fatigue, device benefit, mental well-being, participation, empowerment and user experiences, between upgraded and obsolete hearing aid processors. The economic impact of the upgrade was evaluated using two state-transition microsimulation models of adults using CIs. Results: The multi-site study ran from 20 May 2021 to 21 April 2023, with recruitment from June 2021 to May 2022. A total of 340 Cochlear™ sound processors were upgraded in 304 adults. The adults’ mean age was 77.4 years (SD 6.6), and 48.5% were female. Hearing loss onset occurred on average at 30 years (SD 21.0), with 12 years (SD 6.2) of CI use. The outcomes show significant improvements in speech understanding in noise and reduced communication difficulties, self-reported listening effort and fatigue. Semi-structured interviews have revealed that upgrades alleviated the anxiety and fear of sudden processor failure. Health economic analysis found that the cost-effectiveness of upgrades stemmed from preventing device failures, rather than from access to newer technology features. Conclusions: Our study identified significant clinical and self-reported benefits from upgrading Cochlear™ sound processors. Economic value came from avoiding scenarios where a total failure of device renders its user unable to access sound. The evidence gathered can be used to inform policy on CI processor upgrades for older adults.

Objective: To investigate the effect of varying cross-over frequency (CF) settings for electric-acoustic (EA) stimulation in one ear combined with acoustic (A) hearing in the opposite ear on binaural speech perception, localization and functional performance in real life. Methods: Performance with three different CF settings set according to audiometric-based criterion were compared, following a four week familiarisation period with each, in ten adult cochlear implant recipients with residual hearing in both ears. On completion of all trials participants selected their preferred CF setting. Results: On average, CF settings did not have a significant effect on performance scores. However, higher ratings on device usage were associated with the preferred CF settings. Conclusion: Individuals who use EA + A stimulation may benefit from access to different CF settings to achieve maximal device usage.