English R. King

Influence of cochlear implant insertion depth on performance: a prospective randomized trial.

Objective The purpose of the present study was to assess the influence of electrode insertion length on cochlear implant (CI) performance. Study Design Prospective randomized allocation of CI patients to receive either a standard (26.4 mm)- or medium (20.9 mm)-length electrode array. The processing strategy and electrode insertion number were held constant. The postoperative testing audiologist was blinded to the map details and array. Setting Tertiary referral center. Patients Thirteen adult CI candidates randomized to receive the standard- (n = 7) or medium-length (n = 6) electrode array. Intervention(s) Unilateral CI using standard- or medium-length array from the same implant system. Main Outcome Measures(s) Speech perception was assessed with HINT sentences in quiet and steady-state noise (SNR, +10) and CNC words in quiet at defined intervals. Quality of life was assessed using the Hearing Device Satisfaction Survey and the Abbreviated Profile of Hearing Aid Benefit (APHAB). Music perception was assessed using the Musical Sounds In Cochlear implants (MuSIC) test. Postoperative electrode insertion angle was assessed using reconstructed computed tomographic images. Results Interim analysis necessitated discontinuation of subject enrollment by the institutional review board. There was a trend (p = 0.07) for improved speech perception performance among standard array patients. This difference was significant when the standard array group was increased retrospectively. Quality of life and music perception differences were not apparent between groups. Conclusion Longer electrode insertions (and greater insertion angles) appear to offer better speech perception performance in the early postactivation period when using the same implant system.

Hearing preservation and speech perception outcomes with electric‐acoustic stimulation after 12 months of listening experience

To report on single‐center data of an FDA‐approved clinical trial on the objective benefits of cochlear implantation and subsequent ipsilateral Electric‐Acoustic Stimulation (EAS).

Cochleostomy Versus Round Window Insertions: Influence on Functional Outcomes in Electric-acoustic Stimulation of the Auditory System

Objective To assess the potential influence of 2 different surgical access routes to scala tympani for hearing preservation cochlear implantation on outcomes. Study Design Retrospective review. Setting Tertiary care academic center. Patients Twenty adult subjects participating in a prospective clinical trial on electric-acoustic stimulation. Subjects underwent cochlear implantation with attempted hearing preservation and subsequent ipsilateral electric-acoustic stimulation of the auditory system. Interventions Eight subjects (40%) were implanted using a round window–related cochleostomy and 12 subjects (60%) via a round window approach. Main Outcome Measures Postoperative acoustic hearing preservation and speech perception measures were obtained at defined intervals and compared for both groups with and without the use of the external speech processor. Results The data demonstrate no statistically significant differences in postoperative outcomes for both preservation of residual hearing and unaided and aided speech perception between the cochleostomy and round window groups. Conclusion The results of this investigation suggest that hearing preservation cochlear implantation can be performed either via a round window–related cochleostomy as well as via the round window membrane itself with similar outcomes in terms of both hearing preservation rates as well as speech perception measures.

Long-term Speech Perception in Elderly Cochlear Implant Users

IMPORTANCE A review of a test battery presented in both quiet and noise may clarify what the progression of speech perception abilities is in older adult cochlear implant users and whether the performance declines with advancing age. OBJECTIVE To examine whether older adults (≥65 years) with cochlear implants maintain stable speech perception performance after at least 10 years of listening experience with an external speech processor. DESIGN AND SETTING Retrospective analysis performed in an academic tertiary care center. PARTICIPANTS Fourteen older adult cochlear implant recipients with at least 10 years of listening experience. MAIN OUTCOME MEASURES Speech perception outcomes as measured with Consonant-Nucleus-Consonant words in quiet and Hearing in Noise Test sentences in quiet and steady-state noise were analyzed retrospectively at the 6-month and 1-, 5-, and 10-year postoperative follow-up intervals. RESULTS Consonant-Nucleus-Consonant word scores remained stable between 6 months and 1 year of listening experience, improved significantly (P < .001) between 1 year and 5 years, and remained stable between 5 years and 10 years. Hearing in Noise Test sentence scores in quiet and noise showed a similar pattern, with stability in performance between the 6-month to 1-year and 5-year to 10-year follow-up intervals, and significantly improved performance (P = .04) between the 1-year and 5-year follow-up intervals. CONCLUSIONS AND RELEVANCE On average, patients who undergo cochlear implantation at age 65 years or older do not experience a decline in speech perception performance with extended listening experience and may potentially continue to see improvements beyond the 1-year follow-up interval.

Cochlear Implantation in Cases of Unilateral Hearing Loss: Initial Localization Abilities

Objectives: The present study evaluated early auditory localization abilities of cochlear implant (CI) recipients with normal or near-normal hearing (NH) in the contralateral ear. The goal of the study was to better understand the effect of CI listening experience on localization in this population. Design: Twenty participants with unilateral hearing loss enrolled in a prospective clinical trial assessing outcomes of cochlear implantation (ClinicalTrials.gov Identifier: NCT02203305). All participants received the MED-EL Standard electrode array, were fit with an ear-level audio processor, and listened with the FS4 coding strategy. Localization was assessed in the sound field using an 11-speaker array with speakers uniformly positioned on a horizontal, semicircular frame. Stimuli were 200-msec speech-shaped noise bursts. The intensity level (52, 62, and 72 dB SPL) and sound source were randomly interleaved across trials. Participants were tested preoperatively, and 1, 3, and 6 months after activation of the audio processor. Performance was evaluated in two conditions at each interval: (1) unaided (NH ear alone [NH-alone] condition), and (2) aided, with either a bone conduction hearing aid (preoperative interval; bone conduction hearing aid + NH condition) or a CI (postoperative intervals; CI + NH condition). Performance was evaluated by comparing root-mean-squared (RMS) error between listening conditions and between measurement intervals. Results: Mean RMS error for the soft, medium, and loud levels were 66°, 64°, and 69° in the NH-alone condition and 72°, 66°, and 70° in the bone conduction hearing aid + NH condition. Participants experienced a significant improvement in localization in the CI + NH condition at the 1-month interval (38°, 35°, and 38°) as compared with the preoperative NH-alone condition. Localization in the CI + NH condition continued to improve through the 6-month interval. Mean RMS errors were 28°, 25°, and 28° in the CI + NH condition at the 6-month interval. Conclusions: Adult CI recipients with normal or near-normal hearing in the contralateral ear experienced significant improvement in localization after 1 month of device use, and continued to improve through the 6-month interval. The present results show that binaural acclimatization in CI users with unilateral hearing loss can progress rapidly, with marked improvements in performance observed after only 1 month of listening experience.

Influence of Age at Revision Cochlear Implantation on Speech Perception Outcomes

IMPORTANCE This study reviewed whether advanced age should be a consideration when revision cochlear implantation is warranted. OBJECTIVE To examine whether age at revision cochlear implantation is related to postrevision speech perception performance. DESIGN, SETTING, AND PARTICIPANTS A retrospective analysis was performed in an academic tertiary care center. Participants included 14 younger adults (<65 years) and 15 older adults (≥65 years) who underwent revision cochlear implantation. INTERVENTION Revision cochlear implantation. MAIN OUTCOMES AND MEASURES Speech perception performance, as measured with consonant-nucleus-consonant [CNC] words in quiet, at the best prerevision interval as well as the 3- and 6-month postrevision intervals were compared between the 2 cohorts. The CNC word test consists of 10 lists of 50 phonemically balanced monosyllabic words, scored with a range of 0% to 100% correct. RESULTS Both cohorts experienced a restoration in speech perception scores after revision cochlear implantation compared with their best performance before the revision (mean [SD] CNC word test scores for the younger cohort: 43.9% [25.6%] before revision and 47.7% [21.3%] at 3 months and 47.6% [19.8%] at 6 months after revision; for the older cohort: 36.3% [19.1%] before revision and 35.3% [17.2%] at 3 months and 39.9% [16.3%] at 6 months after revision; F₂,₅₄= 0.93; P = .40). There was no interaction between age at revision surgery and speech perception performance at each assessment interval (F₂,₅₄= 0.51; P = .60). CONCLUSIONS AND RELEVANCE In this study, age at revision cochlear implantation was not related to postrevision speech perception performance. Advanced age should not be considered a contraindication to revision cochlear implantation.

Impact of Electric Stimulation on Residual Hearing.

BACKGROUND Candidacy criteria for cochlear implantation are expanding to include patients with substantial low-to-mid frequency hearing sensitivity. Postoperative hearing preservation has been achieved in cochlear implant recipients, though with variable outcomes. Previous investigations on postoperative hearing preservation outcomes have evaluated intraoperative procedures. There has been limited review as to whether electric stimulation influences hearing preservation. PURPOSE The purpose of this analysis was to evaluate whether charge levels associated with electric stimulation influence postoperative hearing preservation within the first year of listening experience. RESEARCH DESIGN Retrospective analysis of unaided residual hearing and charge levels. STUDY SAMPLE Twenty-eight cochlear implant recipients with postoperative residual hearing in the operative ear and at least 12 mo of listening experience with electric-acoustic stimulation (EAS). DATA COLLECTION AND ANALYSIS Assessment intervals included initial cochlear implant activation, initial EAS activation, and 3-, 6-, and 12-mo postinitial EAS activation. A masked low-frequency bone-conduction (BC) pure-tone average (PTA) was calculated for all participants at each assessment interval. Charge levels for each electrode were determined using the most comfortable loudness level and pulse width values. Charge levels associated with different regions of the electrode array were compared to the change in the low-frequency BC PTA between two consecutive intervals. RESULTS Charge levels had little to no association with the postoperative change in low-frequency BC PTA within the first year of listening experience. CONCLUSIONS Electric charge levels do not appear to be reliably related to the subsequent loss of residual low-frequency hearing in the implanted ear within the first year of EAS listening experience.

Effects of Cochlear Implantation on Binaural Hearing in Adults With Unilateral Hearing Loss

A FDA clinical trial was carried out to evaluate the potential benefit of cochlear implant (CI) use for adults with unilateral moderate-to-profound sensorineural hearing loss. Subjects were 20 adults with moderate-to-profound unilateral sensorineural hearing loss and normal or near-normal hearing on the other side. A MED-EL standard electrode was implanted in the impaired ear. Outcome measures included: (a) sound localization on the horizontal plane (11 positions, −90° to 90°), (b) word recognition in quiet with the CI alone, and (c) masked sentence recognition with the target at 0° and the masker at −90°, 0°, or 90°. This battery was completed preoperatively and at 1, 3, 6, 9, and 12 months after CI activation. Normative data were also collected for 20 age-matched control subjects with normal or near-normal hearing bilaterally. The CI improved localization accuracy and reduced side bias. Word recognition with the CI alone was similar to performance of traditional CI recipients. The CI improved masked sentence recognition when the masker was presented from the front or from the side of normal or near-normal hearing. The binaural benefits observed with the CI increased between the 1- and 3-month intervals but appeared stable thereafter. In contrast to previous reports on localization and speech perception in patients with unilateral sensorineural hearing loss, CI benefits were consistently observed across individual subjects, and performance was at asymptote by the 3-month test interval. Cochlear implant settings, consistent CI use, and short duration of deafness could play a role in this result.

Effect of Cochlear Implantation on Quality of Life in Adults with Unilateral Hearing Loss

Objective: Patients with moderate-to-profound sensorineural hearing loss in 1 ear and normal hearing in the contralateral ear, known as unilateral hearing loss (UHL) or single-sided deafness (SSD), may experience improved quality of life with the use of a cochlear implant (CI) in the affected ear. Quality of life assessment before and after implantation may reveal changes to aspects of hearing beyond those explicitly evaluated with behavioral measures. Methods: The present report completed 2 experiments investigating quality of life outcomes in CI recipients with UHL. The first experiment assessed quality of life during the 1st year of device use with 3 questionnaires: the Speech, Spatial, and Qualities of Hearing Scale (SSQ), the Abbreviated Profile of Hearing Aid Benefit (APHAB), and the Tinnitus Handicap Inventory. Twenty subjects were evaluated preoperatively and 1, 3, 6, 9, and 12 months post-activation. Quality of life results were compared over the study period using traditional scoring methods and the SSQ pragmatic subscales. Subscales specific to localization and speech perception in noise were compared to behavioral measures at the preoperative and 12-month intervals. The 2nd experiment evaluated quality of life preoperatively and at the 12-month interval for CI recipients with UHL and CI recipients with bilateral hearing loss, including conventional CI users and those listening with electric-acoustic stimulation (EAS). The 3 cohorts differed in CI candidacy criteria, including the amount of residual hearing in the contralateral ear. Results: For subjects with moderate-to-profound UHL, receipt of a CI significantly improved quality of life, with benefits noted as early as 1 month after initial activation. The UHL cohort reported less perceived difficulty at the pre- and postoperative intervals than the conventional CI and EAS cohorts, which may be due to the presence of the normal-hearing ear. Each group experienced a significant benefit in quality of life on the APHAB with CI use. Conclusions: Cochlear implantation in cases of substantial UHL may offer significant improvements in quality of life. Quality of life measures revealed a reduction in perceived tinnitus severity and subjective improvements in speech perception in noise, spatial hearing, and listening effort. While self-report of difficulties were lower for the UHL cohort than the conventional CI and EAS cohorts, subjects in all 3 groups reported an improvement in quality of life with CI use.

Round window stimulation for conductive and mixed hearing loss

Objective Assess surgical complications, postoperative residual hearing, and speech perception outcomes of placement of a middle ear implant on the round window in conductive and mixed hearing loss cases. Study Design Single-subject, repeated-measures design where each subject served as his or her own control. Setting Tertiary referral medical systems. Subjects Eighteen subjects with either conductive or mixed hearing loss who could not benefit from conventional amplification were enrolled in a clinical trial investigating vibratory stimulation of the round window. Intervention The floating mass transducer (FMT) was positioned in the round window niche. Main Outcome Measures Unaided residual hearing, and aided sound field thresholds and speech perception abilities were evaluated preoperatively, and at 1, 3, 6, and 10 months post-activation of the external speech processor. Results Six subjects experienced complications that either required further medical management or resolved on their own. There was no difference in residual bone conduction thresholds or unaided word discrimination over time. All subjects experienced a significant improvement in aided speech perception abilities as compared to preoperative performance. Conclusion Subjects with conductive and mixed hearing loss with placement of the FMT in the round window niche experienced improved sound field thresholds and speech perception, without compromising residual hearing thresholds. Vibratory stimulation of the round window via a middle ear implant may be an appropriate treatment option for patients with conductive and mixed hearing loss. Additional research is needed on the preferred placement of the FMT, improvement of functional gain, and methods to limit postoperative complications and need for revision surgery.