Predicting speech perception outcomes following cochlear implantation in adults with unilateral deafness or highly asymmetric hearing loss

Unilateral deafness and highly-asymmetric hearing loss can impair listening abilities in everyday situations, create substantial audiological handicap, and reduce overall quality of life. Preliminary evidence from early-phase studies in adults suggests that cochlear implantation may be effective in reversing some of these detrimental effects. Patient-level data from existing studies was re-analysed to explore potential factors that may be predictive of improved speech perception scores following implantation. The results suggest that duration of deafness in the severe-to-profoundly deaf ear and hearing sensitivity in the better (non-implanted) ear may be relevant when seeking to identify those candidates who are likely to obtain benefit following cochlear implantation

Determining the sample size for future trials of hearing instruments for unilaterally deaf adults: an application of network meta-analysis

Objective: Previous trials have compared the efficacy of hearing instruments to no intervention in adults with single- sided deafness (SSD) or the relative efficacy of different instruments. Network meta-analysis (NMA) was used to refine estimates of effect sizes to determine required sample sizes for further trials.Data Sources: PubMed, EMBASE, MEDLINE, Cochrane, CINAHL, and DARE databases were searched with no restrictions on language, with studies to February 2015 included.Study Selection: Studies were included that 1) assessed hearing instruments in adults with SSD; 2) compared instruments with other instruments, placebo, or no intervention; 3) measured speech perception in quiet/noise and listening ability; 4) were prospective controlled or observational studies.Data Extraction: The following data were extracted: sample size in each group, type of intervention and comparator, type of outcomes, mean outcome scores and their 95% confidence intervals.Data Synthesis: Random-effects meta-analysis was con- ducted to determine pooled effects for each outcome based on direct evidence alone. NMA used graph-theoretical method to determine pooled effects based on indirect evidence. Sample size calculations were conducted for each outcome for each class of evidence.Conclusions: The incorporation of indirect evidence had substantial impacts on some effect sizes but negligible impacts on other effects. The most notable impacts were on self-reported listening ability and measures of speech perception in noise. Changes in effect size estimates and required sample sizes resulting from the incorporation of indirect evidence highlight areas of uncertainty where trials may be feasible to conduct

Improving health-related quality of life in single-sided deafness: a systematic review and meta-analysis

Unilateral severe-to-profound hearing loss, or single-sided deafness (SSD), impairs listening abilities supported by the use of two ears, including speech perception in background noise and sound localisation. Hearing-assistive devices can aid listening by re-routing sounds from the impaired to the non-impaired ear or by restoring input to the impaired ear. A systematic review of the literature examined the impact of hearing-assistive devices on the health-related quality of life (HRQoL) of adults with SSD as measured using generic and disease-specific instruments. A majority of studies used observational designs, and the quality of the evidence was low to moderate. Only two studies used generic instruments. A mixed-effect meta-analysis of disease-specific measures suggested that hearing-assistive devices have a small-to-medium impact on HRQoL. The Speech, Spatial and Qualities of Hearing Scale and the Health Utilities Index Mark 3 (HUI3) were identified as instruments that are sensitive to device-related changes in disease-specific and generic HRQoL, respectively

The Cost-Effectiveness of Bimodal Stimulation Compared to Unilateral and Bilateral Cochlear Implant Use in Adults with Bilateral Severe to Profound Deafness

Objectives: An increasing number of severe-profoundly deaf adult unilateral cochlear implant (CI) users receive bimodal stimulation; that is, they use a conventional acoustic hearing aid (HA) in their non-implanted ear. The combination of electric and contralateral acoustic hearing provides additional benefits to hearing and also to general health-related quality of life compared to unilateral CI use. Bilateral CI is a treatment alternative to both unilateral CI and bimodal stimulation in some healthcare systems. The objective of this study was to conduct an economic evaluation of bimodal stimulation compared to other management options for adults with bilateral severe to profound deafness.Design: The economic evaluation took the form of a cost-utility analysis and compared bimodal stimulation (CI+HA) to two treatment alternatives: unilateral and bilateral CI. The analysis used a public healthcare system perspective based on data from the United Kingdom (UK) and the United States (US). Costs and health benefits were identified for both alternatives and estimated across a patient’s lifetime using Markov state transition models. Utilities were based on Health Utilities Index (HUI3) estimates and health outcomes were expressed in Quality Adjusted Life Years (QALYs). The results were presented using the Incremental Cost-Effectiveness Ratio (ICER) and the Net Monetary Benefit approach to determine the cost-effectiveness of bimodal stimulation. Probabilistic sensitivity analyses explored the degree of overall uncertainty using Monte Carlo simulation. Deterministic sensitivity analyses and Analysis of Covariance identified parameters to which the model was most sensitive; i.e. whose values had a strong influence on the intervention that was determined to be most cost-effective. A Value Of Information analysis was performed to determine the potential value to be gained from additional research on bimodal stimulation.Results: The base case model showed that bimodal stimulation was the most cost-effective treatment option with a decision certainty of 72% and 67% in the UK and US, respectively. Despite producing more QALYs than either unilateral CI or bimodal stimulation, bilateral CI was found not to be cost-effective because it was associated with excessive costs. Compared to unilateral CI, the increased costs of bimodal stimulation were outweighed by the gain in quality of life. Bimodal stimulation was found to cost an extra £174 per person in the UK ($937 in the US) and yielded an additional 0.114 QALYs compared to unilateral CI, resulting in an ICER of £1,521 per QALY gained in the UK ($8,192/QALY in the US). The most influential variable was the utility gained from the simultaneous use of both devices (CI+HA) compared to Unilateral CI. The value of further research was £4,383,922 at £20,000/QALY ($86,955,460 at$50,000/QALY in the US).Conclusions: This study provides evidence of the most cost-effective treatment alternative for adults with bilateral severe to profound deafness from publicly-funded healthcare perspectives of the UK and US. Bimodal stimulation was found to be more cost-effective than unilateral and bilateral CI across a wide range of willingness-to-pay thresholds. If there is scope for future research, conducting interventional designs to obtain utilities for bimodal stimulation compared to unilateral CI would reduce decision uncertainty considerably

Peripheral hearing loss reduces the ability of children to direct selective attention during multi-talker listening

Restoring normal hearing requires knowledge of how peripheral and central auditory processes are affected by hearing loss. Previous research has focussed primarily on peripheral changes following sensorineural hearing loss, whereas consequences for central auditory processing have received less attention. We examined the ability of hearing-impaired children to direct auditory attention to a voice of interest (based on the talker’s spatial location or gender) in the presence of a common form of background noise: the voices of competing talkers (i.e. during multi-talker, or “Cocktail Party” listening). We measured brain activity using electro-encephalography (EEG) when children prepared to direct attention to the spatial location or gender of an upcoming target talker who spoke in a mixture of three talkers. Compared to normally-hearing children, hearing-impaired children showed significantly less evidence of preparatory brain activity when required to direct spatial attention. This finding is consistent with the idea that hearing-impaired children have a reduced ability to prepare spatial attention for an upcoming talker. Moreover, preparatory brain activity was not restored when hearing-impaired children listened with their acoustic hearing aids. An implication of these findings is that steps to improve auditory attention alongside acoustic hearing aids may be required to improve the ability of hearing-impaired children to understand speech in the presence of competing talkers

Feasibility of personalised remote long-term follow-up of people with cochlear implants: a randomised controlled trial

Introduction: substantial resources are required to provide lifelong post-operative care to people with cochlear implants. Most patients visit the clinic annually. We introduced a person-centred remote follow-up pathway, giving patients telemedicine tools to use at home so they would only visit the centre when intervention was required. Objectives: to assess the feasibility of comparing a remote care pathway to the standard pathway in adults using cochlear implants. Design: two-arm Randomised Controlled Trial. Randomisation used a minimisation approach, controlling for potential confounding factors. Participant blinding was not possible, but baseline measures occurred before allocation. Setting: University of Southampton Auditory Implant Service: provider of NHS care. Participants: 60 adults who had used cochlear implants for at least 6 months. Interventions: control group (n = 30) followed usual care pathway. Remote care group (n = 30) received care remotely for 6 months incorporating: •Home hearing in noise test •Online support tool •Self-adjustment of device (only 10 had compatible equipment) Main outcome measures: Primary: change in patient activation; measured using the Patient Activation Measure® Secondary: change in hearing and quality of life; qualitative feedback from patients and clinicians. Results: one participant in the remote care group dropped out. The remote care group showed a greater increase in patient activation than the control group. Changes in hearing differed between the groups. The remote care group improved on the Triple Digit Test hearing test; the control group perceived their hearing was worse on the Speech, Spatial and Qualities of Hearing questionnaire. Quality of life remained unchanged in both groups. Patients and clinicians were generally positive about remote care tools and wanted to continue. Conclusions: adults with cochlear implants were willing to be randomised and complied with the protocol. Personalised remote care for long-term follow-up is feasible and acceptable, leading to more empowered patients

Choosing which ear to implant in adult candidates with functional residual hearing

This study examined whether audiologists consider the potential benefits of contralateral hearing aid use following cochlear implantation when recommending which ear to implant in UK adult candidates with residual hearing. Thirty-four audiologists from providers of adult implantation services completed a decision-choice experiment. Clinicians were willing to consider recommending that the poorer ear be implanted, provided it had been aided continuously, suggesting that their decision making seeks to preserve access to residual hearing in the non-implanted ear where possible. Future approaches to determining candidacy should therefore consider that a sub-set of patients may obtain additional benefit from this residual hearing following implantation

Development and validation of the Nottingham Auditory Milestones (NAMES) profile for deaf children under 2 years old, using cochlear implants

Objectives: Clinicians face considerable challenges in setting appropriate auditory goals for babies and young children who receive cochlear implants. This paper describes the rationale, organisation, implementation and validation of the Nottingham Auditory Milestones profile that was developed to address these challenges. Methods: The use of the profile has been fully integrated into the post-operative pathway at the Nottingham Auditory Implant Programme since 2009. Data is presented on a cohort of 30 children who received bilateral cochlear implants under the age of two and who have no other diagnosed difficulties. The data was used to validate the profile's structure and characterise the expected development trajectory for this population of children. Results: The analysis of routine data from the children confirmed that the profile's structure reflected the typical order and rate at which skills emerged and were acquired over the first three years following cochlear implantation. The distribution of profile scores across five assessment time-points established a developmental trajectory for typically-developing children. Three case studies describe the use of the profile to set consistent expectations for progress for a wide range of children. Discussion: The development trajectory established using the profile provides a mechanism to identify children not making the expected progress, in order to support the need for a review of approach or a differential diagnosis. Conclusion: The Nottingham Auditory Milestones profile is an accessible and practical tool for identifying, monitoring and appraising the auditory achievements of deaf babies and young children in the first three years following cochlear implantation

Access to aidable residual hearing in adult candidates for cochlear implantation in the UK

Guidance from the National Institute for Health and Care Excellence (NICE) permits candidates to receive a cochlear implant provided they only hear sounds louder than 90 dB HL at 2 and 4 kHz. In some patients, their level of residual hearing may be sufficient to warrant the use of a hearing aid in their non-implanted ear. A survey of unilaterally-implanted adults indicated that those implanted since the publication of NICE guidance were almost seven times more likely to use a hearing aid than those implanted prior to this. If contralateral hearing aid use provides additional benefits over implant use alone, it may be appropriate to consider the capacity to use residual hearing following implantation when determining candidacy

EEG activity evoked in preparation for multi-talker listening by adults and children

Selective attention is critical for successful speech perception because speech is often encountered in the presence of other sounds, including the voices of competing talkers. Faced with the need to attend selectively, listeners perceive speech more accurately when they know characteristics of upcoming talkers before they begin to speak. However, the neural processes that underlie the preparation of selective attention for voices are not fully understood. The current experiments used electroencephalography (EEG) to investigate the time course of brain activity during preparation for an upcoming talker in young adults aged 18-27 years with normal hearing (Experiments 1 and 2) and in typically-developing children aged 7-13 years (Experiment 3). Participants reported key words spoken by a target talker when an opposite-gender distractor talker spoke simultaneously. The two talkers were presented from different spatial locations (±30° azimuth). Before the talkers began to speak, a visual cue indicated either the location (left/right) or the gender (male/female) of the target talker. Adults evoked preparatory EEG activity that started shortly after