Cochlear implantation in unilateral hearing loss: impact of short- to medium-term auditory deprivation.

Introduction: Single sided deafness (SSD) results in profound cortical reorganization that presents clinically with a significant impact on sound localization and speech comprehension. Cochlear implantation (CI) has been approved for two manufacturers' devices in the United States to restore bilateral function in SSD patients with up to 10 years of auditory deprivation. However, there is great variability in auditory performance and it remains unclear how auditory deprivation affects CI benefits within this 10-year window. This prospective study explores how measured auditory performance relates to real-world experience and device use in a cohort of SSD-CI subjects who have between 0 and 10 years of auditory deprivation. Methods: Subjects were assessed before implantation and 3-, 6-, and 12-months post-CI activation via Consonant-Nucleus-Consonant (CNC) word recognition and Arizona Biomedical Institute (AzBio) sentence recognition in varying spatial speech and noise presentations that simulate head shadow, squelch, and summation effects (S0N0, SSSDNNH, SNHNSSD; 0 = front, SSD = impacted ear, NH = normal hearing ear). Patient-centered assessments were performed using Tinnitus Handicap Inventory (THI), Spatial Hearing Questionnaire (SHQ), and Health Utility Index Mark 3 (HUI3). Device use data was acquired from manufacturer software. Further subgroup analysis was performed on data stratified by <5 years and 5-10 years duration of deafness. Results: In the SSD ear, median (IQR) CNC word scores pre-implant and at 3-, 6-, and 12-months post-implant were 0% (0-0%), 24% (8-44%), 28% (4-44%), and 18% (7-33%), respectively. At 6 months post-activation, AzBio scores in S0N0 and SSSDNNH configurations (n = 25) demonstrated statistically significant increases in performance by 5% (p = 0.03) and 20% (p = 0.005), respectively. The median HUI3 score was 0.56 pre-implant, lower than scores for common conditions such as anxiety (0.68) and diabetes (0.77), and comparable to stroke (0.58). Scores improved to 0.83 (0.71-0.91) by 3 months post-activation. These audiologic and subjective benefits were observed even in patients with longer durations of deafness. Discussion: By merging CI-associated changes in objective and patient-centered measures of auditory function, our findings implicate central mechanisms of auditory compensation and adaptation critical in auditory performance after SSD-CI and quantify the extent to which they affect the real-world experience reported by individuals.

Longitudinal Auditory Benefit for Elderly Patients After Cochlear Implant for Bilateral Hearing Loss, Including Those Meeting Expanded Centers for Medicare & Medicaid Services Criteria.

OBJECTIVE: To examine the effect of patient age on longitudinal speech understanding outcomes after cochlear implantation (CI) in bilateral hearing loss. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary academic center. PATIENTS: One thousand one hundred five adult patients with bilateral hearing loss receiving a unilateral CI between 1987 and 2022InterventionsNone. MAIN OUTCOME MEASURES: Postoperative speech recognition outcomes, including AzBio sentences, consonant-nucleus-consonant word, and Hearing in Noise Test in quiet were analyzed at short-term (<2 yr), medium-term (2-8 y), and long-term (>8 yr) term postoperative intervals. RESULTS: Eighty-six very elderly (>80 yr), 409 elderly (65-80 yr), and 709 nonelderly (18-65 yr) patients were included. Short-term postoperative AzBio scores demonstrated similar magnitude of improvement relative to preoperative scores in the very elderly (47.6, 95% confidence interval [CI], 28.9-66.4), elderly (49.0; 95% CI, 39.2-58.8), and nonelderly (47.9; 95% CI, 35.4-60.4). Scores for those older than 80 years remained stable after 2 years after implant, but in those 80 years or younger, scores continued to improve for up to 8 years (elderly: 6.2 [95% CI, 1.5-12.4]; nonelderly: 9.9 [95% CI, 2.1-17.7]) after implantation. Similar patterns were observed for consonant-nucleus-consonant word scores. Across all age cohorts, patients with preoperative Hearing in Noise Test scores between 40 and 60% had similar scores to those with preoperative scores of less than 40%, at short-term (82.4, 78.9; 95% CI, -23.1 to 10.0), medium-term (77.2, 83.9; 95% CI, -15.4 to 8.2), or long-term (73.4, 71.2; 95% CI, -18.2 to 12.2) follow-up. CONCLUSIONS: Patients older than 80 years gain significant and sustained auditory benefit after CI, including those meeting expanded Centers for Medicare & Medicaid Service criteria for implantation. Patients younger than 80 years demonstrated continued improvement over longer periods than older patients, suggesting a role of central plasticity in mediating CI outcomes as a function of age.

Are Speech Perception Scores in Cochlear Implant Recipients Consistent Across Different Tests?

OBJECTIVE: Cochlear implant (CI) candidacy and postoperative outcomes are assessed using sets of speech perception tests that vary from center to center, limiting comparisons across institutions and time periods. The objective of this study was to determine if scores on one speech perception test could be reliably predicted from scores on another test. STUDY DESIGN: Arizona Biomedical (AzBio) Sentence Test, Consonant-Nucleus-Consonant word (CNCw), and Hearing in Noise Test (HINT) scores in quiet for the implanted ear were collected for individuals who received a CI between 1985 and 2019. Scores collected during the same testing session were analyzed using Bland-Altman plots to assess agreement between testing methods. Simple linear regression with logit transformation was used to generate predictive functions and 95% confidence intervals for expected mean and individual scores. SETTING: Single academic medical center. PATIENTS: A total of 1,437 individuals with a median age of 59.9 years (range, 18-95 yr) and 46% (654 of 1,437) male. INTERVENTIONS: N.A. MAIN OUTCOME MEASURES: Agreement as a function of test score, mean, variance, and correlation coefficients. RESULTS: A total of 2,052 AzBio/CNCw, 525 AzBio/HINT, and 7,187 CNCw/HINT same-session score pairings were identified. Pairwise test comparisons demonstrated limited agreement between different tests performed in the same session, and a score correlation between different speech tests revealed large variances. CONCLUSION: Transformation functions between test batteries were predictive of mean scores but performed poorly for prediction of individual scores. Point-wise comparisons of scores across CI test batteries should be used with caution in clinical and research settings.

Rehabilitation and Psychosocial Determinants of Cochlear Implant Outcomes in Older Adults.

OBJECTIVE: The cochlear implant (CI) has been shown to be associated with better hearing, cognitive abilities, and functional independence. There is variability however in how much benefit each recipient derives from his or her CI. This study's primary objective is to determine the effects of individual and environmental characteristics on CI outcomes. DESIGN: Seventy-six adults who developed postlingual severe to profound hearing loss and received their first unilateral CI at 65 years and older were eligible for the study. Fifty-five patients were asked to participate and the 33 (60%) with complete data were classified as "group 1." The remaining patients were placed in "group 2." Primary outcomes included changes in quality of life and open-set speech perception scores. Independent variables included age, health status, trait emotional intelligence (EI), comfort with technology, and living arrangements. Survey outcomes and audiological measurements were collected prospectively at 12 months after surgery, whereas preoperative data were collected retrospectively. Comparisons between groups 1 and 2 were made. Wilcoxon signed rank test, Spearman correlations, Mann-Whitney tests, Chi-square tests, and linear regressions were performed only on group 1 data. RESULTS: Having a CI was associated with improved quality of life and speech perception. Familiarity with electronic tablets was associated with increased 12-month postoperative AzBio gains when adjusted for preoperative AzBio scores (adjusted p = 0.019), but only marginally significant when a family-wise error correction was applied (p = 0.057). Furthermore, patients who lived with other people scored at least 20 points higher on the AzBio sentences than those who lived alone (adjusted p = 0.046). Finally, consultation with an auditory rehabilitation therapist was associated with higher self-reported quality of life (p = 0.035). CONCLUSION: This study suggests that in a cohort of older patients cochlear implantation is associated with a meaningful increase in both quality of life and speech perception. Furthermore, it suggests the potential importance of adjunct support and services, including the tailoring of CI rehabilitation sessions depending on the patient's familiarity with technology and living situation. Investment in rehabilitation and other services is associated with improvements in quality of life and may mitigate clinical, individual and social risk factors for poor communication outcome.

Clinical and psychosocial risk factors of hearing outcome in older adults with cochlear implants.

OBJECTIVES/HYPOTHESIS: To identify psychosocial determinants of speech perception (SP) outcome in older adults after cochlear implant (CI) surgery. STUDY DESIGN: Retrospective study. METHODS: Subjects received their CI at age 45 years or older and had at least 12 months of device experience. Independent variables consisted of the Charlson Comorbidity Index, history of depression, length of hearing loss and amplification use, residential status, education and gaps in SP data. Regression models were evaluated for associations with open-set SP gains at 3 months and 12 months, and in the 6- to 12-month time interval. RESULTS: Every 10% increase in the proportion of life spent using a hearing aid was associated with a 2% to 3% decrement in SP gain within the first 3 months of CI use. Later and overall 1y SP gains were negatively impacted by poorer general health, lower education level, and residence in an assisted-living facility. Patients with gaps in SP data at later time points were also more likely to have poorer health and to live in assisted-living facilities. The absence of two or more evaluations was associated on average with 6.3% lower SP outcome compared to subjects with one or fewer missing data points. Age at CI had no influence on the size of post-operative SP gains. CONCLUSIONS: Auditory deprivation and the influence of psychosocial and health factors on engagement in postsurgical rehabilitation services may impact CI outcomes more than has been previously reported. These findings have policy implications and highlight the need for more effective delivery of hearing rehabilitation services to an aging population.

Cochlear implant rehabilitation in older adults: literature review and proposal of a conceptual framework.

OBJECTIVES: To review studies investigating cochlear implant (CI) outcomes in older adults, and to develop a conceptual framework demonstrating important interactions between characteristics of hearing disability, aging, and the CI intervention. DESIGN: Review of English literature with titles containing the words "cochlear implant" and generic term referring to older adults or numerical value for age greater than 65. RESULTS: Hearing loss is a prevalent consequence of aging and poses special challenges for older adults. Particularly when superimposed on other age-related conditions, presbycusis (age-related hearing loss) places older adults at risk for social isolation and associated psychological and general health sequelae. The increasing cognitive demand of verbal communication and the diminished sense of social and physical connectedness can contribute to a feeling of vulnerability and poor health that worsens with advancing presbycusis. This cascade of downstream effects of hearing loss has implications for the self-assessment of health-related quality of life (HRQoL) and resulting estimates of associated costs. There is accumulating evidence of a potential role for CI in older adults with poor word understanding despite conventional hearing aid use. This review of the literature provides strong evidence of the benefits of restoring communication capacity in the deaf and hard-of-hearing geriatric population. There is, however, a lack of attention to communication performance in the real world and HRQoL outcomes, and significant gaps in knowledge regarding how CI rehabilitation interacts with changing psychosocial and functional status with aging. CONCLUSION: A broader conceptual framework than is currently available for the role of CI rehabilitation in the management of severe-to-profound hearing loss in older adults is proposed. It is posited that the use of such a model in future investigations is needed to guide multidisciplinary investigations into the unique challenges of hearing loss in older adults and may open new opportunities for innovation.

Cochlear implantation in patients with neurofibromatosis type 2 and bilateral vestibular schwannoma.

OBJECTIVE: To investigate the results of cochlear implantation in patients with neurofibromatosis Type 2 (NF2) and bilateral vestibular schwannoma. STUDY DESIGN: Retrospective case review. SETTING: Three academic tertiary referral centers. PATIENTS: Seven patients with NF2 and bilateral vestibular schwannoma who lost hearing in at least one ear after treatment of their tumor (surgery or radiation therapy). INTERVENTION: Cochlear implantation after treatment of their vestibular schwannoma. MAIN OUTCOME MEASURE: Postimplantation audiometric scores (pure-tone average thresholds, consonant-nucleus-consonant (CNC) words/phonemes, Central Institute for the Deaf (CID) sentences, Hearing in Noise Test (HINT) quiet/noise, and Monosyllable, Trochee, Spondee (MTS) recognition/category tests), patient satisfaction, and device use patterns. RESULTS: The average age at implantation was 40 years (range, 16-57 yr). Follow-up ranged from 6 to 88 months after implantation. Three patients were implanted with residual useful hearing in the contralateral ear, whereas four patients had no hearing in the contralateral ear. Hearing loss was due to surgical excision of tumor (n=5) or gamma-knife radiotherapy (n=2). Postactivation pure-tone average thresholds in the implanted ear ranged from 30 to 55 dB (average, 32.5 dB), although speech reception testing varied considerably among subjects. Despite this variability, all patients continue to use the device on a daily basis. CONCLUSION: In selected cases of deafness in patients with NF2 where there has been anatomic preservation of the auditory nerve after acoustic neuroma resection or radiation therapy, cochlear implantation may offer some improvement in communication skills, including the possibility of open-set speech communication in some patients. These results compare favorably to the auditory brainstem implant offering an alternative for hearing rehabilitation in patients with NF2.

Predictive models for cochlear implantation in elderly candidates.

OBJECTIVE: An aging American population carries a high prevalence of profound sensorineural hearing loss. We examined the performance of multichannel cochlear implant recipients in a large database of adult subjects. DESIGN: Nonconcurrent prospective study of a national cohort with multivariate regression analysis of preoperative and postoperative performance variables in multichannel cochlear implant recipients. We applied models of prediction established in previous studies to the observed results. SETTING: Referral centers with active cochlear implant programs. PATIENTS: Adolescents and adults with profound hearing loss (N = 749; age range, 14-91 years). MAIN OUTCOME MEASURE: Postoperative monosyllabic word recognition. RESULTS: The population 65 years and older demonstrated a clinically insignificant 4.6%-smaller postoperative word score compared with the population younger than 65 years. When duration of deafness exceeded 25 years, elderly recipients demonstrated higher word scores than their younger counterparts. A more significant factor affecting outcomes is the ratio of duration of deafness to age at implantation. CONCLUSIONS: Age at implantation carried relatively little predictive value for postoperative performance in subjects 65 years and older. Although a small decrement in mean speech recognition scores was evident, the clinical significance of this difference is questionable when all of the results observed in elderly patients are considered. A shorter percentage of life spent in severe-to-profound sensorineural hearing loss suggests a foundation of acoustic/auditory processing in the elderly cohort that may mitigate potential physiological effects associated with advanced age. This study confirms and extends previous observations that duration of profound deafness and residual speech recognition carry higher predictive value than the age at which an individual receives an implant.

Cochlear implant outcome is not influenced by the choice of ear.

OBJECTIVES: This study tested the hypothesis that patients with residual hearing in the nonimplanted ear had the same cochlear implant benefit whether the implanted ear had profound or severe hearing loss. DESIGN: A retrospective chart review of adult cochlear implant recipients with postlingual hearing loss. Patients were categorized according to the pure-tone average of the implanted and contralateral ears as (a) bilateral profound, (b) severe-profound, and (c) bilateral severe. The results of a test battery of spoken language measures were compared among patients belonging to these hearing categories at 6, 12, and 24 months after surgery, using a t-test and multivariate regression analyses. RESULTS: The presence of residual hearing in one or both ears was associated with significantly higher postoperative speech perception scores compared with participants with bilateral profound hearing loss. Among participants with similar amounts of residual hearing in the nonimplanted ear, however, there was no difference in speech recognition scores between those with profound and those with severe hearing loss in the implanted ear. CONCLUSIONS: Among participants with asymmetric hearing loss, there is no additional benefit to implanting the better-hearing ear that can be preserved for use with a hearing aid for better speech understanding in noise and sound localization. These results suggest that the additional benefit received by patients with residual hearing is mediated by trophic effects on crossed pathways in the central nervous system and is independent of the preoperative functional status of the implanted ear.

Central effects of residual hearing: implications for choice of ear for cochlear implantation.

OBJECTIVES/HYPOTHESIS: The study tested the hypothesis that among patients with similar levels of residual hearing in the nonimplanted ear, speech perception outcome is the same whether or not the implanted ear has profound or severe levels of hearing loss. STUDY DESIGN: Retrospective. METHODS: Levels of hearing loss in postlingually deafened adults who had cochlear implantation at Johns Hopkins University (Baltimore, MD) between 1991 and 2002 were classified according to pure-tone averages as bilateral severe (n = 20), severe-profound (severe in one ear and profound in the other) (n = 23), and bilateral profound (n = 43). There was no significant difference in the age at onset and duration of deafness among the three patient groups. Individuals in the bilateral severe and severe-profound groups had comparable levels of severe hearing loss in their nonimplanted ears, whereas those in severe-profound and bilateral profound groups had comparable levels of profound hearing loss in their implanted ears. Speech perception performance was evaluated using words from the Consonant Nucleus Consonant word list, Hearing in Noise Test sentences in quiet, and Central Institute for the Deaf sentences through recorded presentation at 70 dB sound pressure level (SPL). RESULTS: Despite the profound hearing loss of the implanted ear in the asymmetrical group, there was no significant difference in mean speech perception scores compared with the bilateral severe group within the first year after implant surgery. By comparison, the bilateral profound group had lower speech perception results compared with patients with residual hearing in one or both ears. CONCLUSION: The study results suggest that implantation of the profoundly deafened ear does not diminish the functional advantage conferred by residual hearing in a patient with asymmetrical hearing loss. Therefore, the central auditory pathway may be the site at which persistent auditory function has its most beneficial effects.

GJB2 gene mutations in cochlear implant recipients: prevalence and impact on outcome.

OBJECTIVE: To determine the prevalence of GJB2 gene mutations in patients undergoing cochlear implantation (CI) and their impact on rehabilitative outcome following implantation. DESIGN: Prospective determination of GJB2 mutation by sequence analysis by denaturing high-performance liquid chromatography and its correlation with outcome following CI. SETTINGS: Two tertiary academic medical centers. PATIENTS: Subjects who have met the audiologic criteria and have undergone CI. RESULTS: Of 77 cochlear implant recipients screened, 13 (18%) harbored a detectable sequence alteration in the GJB2 gene. Only 3 of these 13 patients had hearing loss clearly attributable to a biallelic GJB2 mutation. There were 2 patients with homozygous mutations, including a 35delG and a 167delT mutation, and a third with a compound heterozygous mutation. Of the remaining 10 patients, 8 had 1 deafness allele, while 2 had a normal polymorphism that was not believed to be implicated in the hearing loss. Six patients had the common 35delG mutation: 5 patients had heterozygous mutations, which are probably not related to the underlying hearing loss (a second deafness allele cannot be ruled out in these cases because of the screening methodology used), while 1 patient had a homozygous mutation, which was clearly implicated in the patient's deafness. Rehabilitative outcome among those with detectable sequence alterations, as well as the 3 patients with biallelic mutations, varied but were similar on average when compared with outcomes seen in our entire CI population. CONCLUSIONS: A large percentage of implant candidates harbor mutations or sequence alterations in the GJB2 gene, although only a small number of these changes are biallelic and a clear cause of the hearing loss. These results demonstrate that patients with GJB2-related deafness clearly benefit from CI.

Effects of central nervous system residua on cochlear implant results in children deafened by meningitis.

BACKGROUND: This study explored factors associated with speech recognition outcomes in postmeningitic deafness (PMD). The results of cochlear implantation may vary in children with PMD because of sequelae that extend beyond the auditory periphery. OBJECTIVE: To determine which factors might be most determinative of outcome of cochlear implantation in children with PMD. DESIGN: Retrospective chart review. SETTING: A referral center for pediatric cochlear implantation and rehabilitation. SUBJECTS: Thirty children with cochlear implants who were deafened by meningitis were matched with subjects who were deafened by other causes based on the age at diagnosis, age at cochlear implantation, age at which hearing aids were first used, and method of communication used at home or in the classroom. MAIN OUTCOME MEASURE: Speech perception performance within the first 2 years after cochlear implantation and its relationship with presurgical cognitive measures and medical history. RESULTS: There was no difference in the overall cognitive or postoperative speech perception performance between the children with PMD and those deafened by other causes. The presence of postmeningitic hydrocephalus, however, posed greater challenges to the rehabilitation process, as indicated by significantly smaller gains in speech perception and a predilection for behavioral problems. By comparison, cochlear scarring and incomplete electrode insertion had no impact on speech perception results. CONCLUSIONS: Although the results demonstrated no significant delay in cognitive or speech perception performance in the PMD group, central nervous system residua, when present, can impede the acquisition of speech perception with a cochlear implant. Central effects associated with PMD may thus impact language learning potential; cognitive and behavioral therapy should be considered in rehabilitative planning and in establishing expectations of outcome.

Cochlear implantation in patients with bilateral Ménière's syndrome.

OBJECTIVE: To evaluate the indications and clinical outcomes (audiologic and vestibular) in patients with Ménière's syndrome who have undergone cochlear implantation. STUDY DESIGN: This is a retrospective review of patients at a large tertiary academic medical center. PATIENTS: Nine patients were included in the study with AAO-HNS criteria for diagnosis of Ménière's syndrome as well as bilateral severe to profound sensorineural hearing loss as an indication for undergoing cochlear implantation. Audiologic criteria for implantation were considered in the context of speech recognition performance with well-fit, powerful hearing aids noting large fluctuations in performance levels in some patients. In all cases, the poorer hearing ear was implanted. Seven subjects had bilateral disease and had progressed to profound sensorineural hearing loss. The average age of the patients was 61 years. Six patients had undergone previous surgery to control vertigo, including endolymphatic shunt surgery and vestibular nerve section. No patient had received previous treatment with intra-tympanic gentamicin. Symptoms of Ménière's syndrome had been present in all patients for at least 10 years before implantation. INTERVENTION: Cochlear Implantation. MAIN OUTCOME MEASURES: Pre- and Postoperative audiometric scores (monosyllable words/phonemes, Central Institute for the Deaf (CID) sentences, Hearing in Noise Test (HINT) in quite/noise (+10 db)), pre- and postoperative vestibular symptoms (number of vestibular attacks, aural fullness, tinnitus). RESULTS: Follow-up after implantation ranged from 1 to 5 years. Average 6 month postimplantation scores were: monosyllable words/phonemes = 52%/65%, CID sentences = 82%, HINT in quiet/noise = 70%/50%. Average 1-year postimplant scores were: monosyllable words/phonemes = 60%/76%, CID sentences = 97%, HINT in quiet/noise = 89%/78%. Postoperative speech recognition scores were, on average, substantially greater than preoperative scores. While there were few complications associated with implantation, some patients experienced alterations in their implant performance in association with fluctuations in vestibular symptoms. CONCLUSIONS: Patients with advanced binaural involvement with Ménière's Disease may present a challenge to conventional criteria for cochlear implant candidacy because of fluctuating symptoms. We observed significant benefit over baseline in a consecutive series of patients with Ménière's syndrome who progressed to bilateral, severe-to-profound sensorineural hearing loss and underwent cochlear implantation. Further, previous vestibular surgery, including labyrinthectomy, does not contraindicate cochlear implantation.

Impact of cochlear implants on the functional health status of older adults.

OBJECTIVES: To assess the impact of cochlear implantation on quality of life changes in older adults aged 50 years and above. STUDY DESIGN: Retrospective study by questionnaire and chart review. METHODS: Forty-seven patients aged 50 to 80 years (mean age, 63.4 y [SD = 8.6 y]), who have multiple-channel cochlear implants received at The Listening Center at Johns Hopkins Hospital, completed the Ontario Health Utilities Index Mark 3 survey and a questionnaire on quality of life changes. Health utility scores before and after cochlear implantation were measured, and audiologic data before implantation and at 6 months and 1 year after implantation were analyzed. RESULTS: Cochlear implantation in older adults is associated with a mean gain in health utility(P <.0001) of 0.24 (SD = 0.33), which corresponds to a favorable cost-utility of $9530 per quality-adjusted life-year. Improvements in hearing and emotional health attributes were primarily responsible for this increase in health-related quality of life measure. There was a significant increase in speech perception scores at 6 months after surgery (P <.0001 for both CID sentence and monosyllabic word tests) and a strong correlation between the magnitude of health utility gains and the postoperative increase in speech perception scores (r = 0.45, P <.05). CONCLUSIONS: Cochlear implants have a significant impact on the quality of life of older deaf patients, and are a cost-effective intervention in this population. Improvements in speech perception are predictive of gains in health-related quality of life and associated emotional benefits after cochlear implantation.