Economic Analysis of Cochlear Implants in Adults With Bilateral Severe-to-Profound Hearing Loss. A Systematic Review of the Literature.

OBJECTIVE: To determine the cost-effectiveness or cost-utility of cochlear implants (CI) in adults with severe to profound bilateral hearing loss. DATABASES REVIEWED: PubMed (Medline), The Cochrane Library, Embase via Elsevier, EBSCOhost CINAHL, and Scopus. METHODS: The study included adult participants with severe to profound bilateral neurosensory hearing loss. The analysis encompassed quality of life improvements, costs, cost-effectiveness, cost-utility, cost-benefit, quality-adjusted life year (QALY), incremental cost-effectiveness ratio (ICER), and incremental cost-utility ratio (ICUR). Systematic reviews, meta-analyses, case series, and prospective or retrospective cohort studies published in English between 2010 and 2023 were retrieved. Exclusion criteria included incomplete studies, abstracts, clinical cases, editorials, letters, studies involving pediatric populations, single-side deafness, methodology research, noneconomic aspects of CI, mixed child and adult data, and studies published before 2010. The risk of bias was assessed following the criteria outlined in Appendix I of the economic evaluation's quality assessment as per the NICE Guideline Development Method. RESULTS: Ten articles met the criteria and were included in the qualitative synthesis. One study conducted a prospective cost-utility analyses, one carried out a cost-benefit analyses, one was a randomized controlled clinical trial focusing on cost-utility, and another was a clinical trial addressing cost-effectiveness. Six studies employed Markov models, and one study utilized uniquely the Monte Carlo method. None quantified the economic impact of improved hearing on cognitive function. CONCLUSIONS: The heterogeneity of sources impacted data quality. Unilateral and sequential bilateral CI appeared to be cost-effective when compared with bilateral hearing aids or nontechnological support. When properly indicated, simultaneous bilateral CIs are cost-effective compared to no interventions and to unilateral cochlear implantation through differential discounting or variations from the base cases, especially with a life expectancy of 5-10 years or longer.

Differences in music appreciation between bilateral and single-sided cochlear implant recipients.

OBJECTIVE: To compare changes in music appreciation after cochlear implant (CI) surgery for patients with bilateral and single-sided deafness (SSD). METHODS: A retrospective cohort study was performed on all adult CI unilateral or bilateral recipients from November 2019 to March 2023. Musical questionnaire subset data from the Cochlear Implant Quality of Life (CIQOL) - 35 Profile Instrument Score (maximum raw score of 15) was collected. Functional CI assessment was measured with CI-alone speech-in-quiet (SIQ) scores (AzBio and CNC). RESULTS: 22 adults underwent CI surgery for SSD and 21 adults for bilateral deafness (8 sequentially implanted). Every patient group had clinically significant improvements (p < 0.001) in mean SIQ scores in the most recently implanted ear (Azbio (% correct) SSD: 14.23 to 68.48, bilateral: 24.54 to 82.23, sequential: 6.25 to 82.57). SSD adults on average had higher music QOL scores at baseline (SSD: 11.05; bilateral: 7.86, p < 0.001). No group had significant increases in raw score at the first post-operative visit (SSD: 11.45, p = 0.86; bilateral: 8.15, p = 0.15). By the most recent post-implantation evaluation (median 12.8 months for SSD, 12.3 months for bilateral), SSD adults had a significant increase in raw score from baseline (11.05 to 12.45, p = 0.03), whereas bilaterally deafened (7.86 to 9.38, p = 0.12) adults had nonsignificant increases. CONCLUSIONS: SSD patients demonstrate higher baseline music appreciation than bilaterally deafened individuals regardless of unilateral or bilateral implantation and are more likely to demonstrate continued improvement in subjective music appreciation at last follow-up even when speech perception outcomes are similar.

Troubleshooting Cochlear Implant Malfunction Using Neural Response Telemetry and Normal Saline.

Cochlear implantation has become a standard of care for a child diagnosed with bilateral profound sensorineural hearing loss with a structured surgical standard operating procedure. A 3-year-old boy with bilateral profound prelingual sensorineural deafness underwent a Med-EL Sonata Ti100 implant. We faced a peculiar situation intraoperatively after inserting the electrodes and closing the wound. The impedance recording indicated high ground path impedance with short-circuiting of few electrodes. As a bionic implant, its electronic components may at times malfunction both intraoperatively and/or postoperatively; therefore, neural response telemetry (NRT) was invented to check it. By using NRT and a few milliliters of normal saline, we were able to diagnose as well as rectify the malfunctioning of the implant.

Bilateral, Sequential Sudden Hearing Loss in a Patient With Multiple COVID-19 Infections and Potential Implications on Subsequent Cochlear Implant Performance.

Viruses are often implicated as a cause of sensorineural hearing loss (SNHL), particularly sudden cases, including COVID-19. Determining the viral mechanism that leads to hearing loss is necessary for its future prevention and treatment. The 47-year-old woman who is the subject of this case study presented with sudden SNHL following multiple infections of COVID-19. Following a trial of a contralateral routing of sound device, she received a right cochlear implant (CI). Following a period of high performance, additional cases of COVID-19 infection and device failure issues resulted in the explant/reimplant of 1 ear and implantation of the contralateral ear. Despite extensive rehabilitation after these events, the patient continues to experience difficulties in speech understanding, not reaching her initial high levels of right ear performance. Further research is needed to determine the implications of COVID-19 as it relates to SNHL. This case study aimed to highlight the course of treatment and provide insight into the impact of COVID-19 on sudden hearing loss and its relationship to CI performance.

Importance of age at 2nd implantation and interimplant interval to the outcome of bilateral prelingually deafened pediatric cochlear implantation.

BACKGROUND: In Taiwan, the number of cases of sequential bilateral pediatric cochlear implantation (CI) is increasing but data regarding its effectiveness and impact of the reimbursement policy are lacking. We examined the speech perception and quality of life (QOL) of bilateral prelingually deaf children who underwent sequential CI, considering the effects of age at the time of second implantation and interimplant interval. METHODS: We enrolled 124 Mandarin-speaking participants who underwent initial cochlear implant (CI1) in 2001-2019 and a second CI (CI2) in 2015-2020. Patients were followed up for ≥2 years and were categorized into groups based on age at the time of CI2 implantation (<3.5, 3.6-7, 7.1-10, 10.1-13, and 13.1-18 years) and interimplant interval (0.5-3, 3.1-5, 5.1-7, 7.1-10, and >10 years). We evaluated speech perception, device usage rates, and QOL using subjective questionnaires (Speech, Spatial, and Qualities of Hearing and Comprehension Cochlear Implant Questionnaire). RESULTS: Speech perception scores of CI2 were negatively correlated with ages at the time of CI1 and CI2 implantation and interimplant interval. Older age and a longer interimplant interval were associated with higher nonuse rates for CI2 and worse auditory performance and QOL. Among individuals aged >13 years with interimplant intervals >10 years, up to 44% did not use their second ear. Patients aged 7.1 to 10 years had better speech perception and higher questionnaire scores than those aged 10.1 to 13 and 13.1 to 18 years. Furthermore, patients aged 10.1 to 13 years had a lower rate of continuous CI2 usage compared to those aged 7.1 to 10 years. CONCLUSION: Timely implantation of CI2 is essential to achieve optimal outcomes, particularly among sequentially implanted patients with long-term deafness in the second ear and no improvement with hearing aids following CI1 implantation. For CI2 implantation, an upper limit of age of 10 years and interimplant interval of 7 years are essential to prevent suboptimal outcomes. These data can provide useful information to implant recipients, their families, and medical and audiological professionals, enabling a comprehensive understanding of the benefits and potential impacts of the timing of CI2 implantation.

Are children with unilateral sensorineural hearing loss receiving cochlear implants?

INTRODUCTION: The US Food and Drug Administration (FDA) granted its first approval for cochlear implants (CI) in children with bilateral sensorineural hearing loss (SNHL) in 1990. In 2019, the FDA expanded CI indications to include children with unilateral SNHL. OBJECTIVE: The aim of this study was to assess the prevalence of children with unilateral SNHL in the population of new pediatric CI recipients between 2012 and 2021. METHODS: A retrospective analysis using the American College of Surgeons National Surgical Quality Improvement Pediatric database examined patients under 18 years of age with bilateral or unilateral SNHL who underwent CI between 2012 and 2021. Current Procedural Terminology code 69930 identified patients with 'cochlear device implantation, with or without mastoidectomy.' The percentage of children undergoing CI for unilateral versus bilateral SNHL during the study period was calculated and subjected to statistical analysis. RESULTS: 9863 pediatric CI patients were included with a mean age of 5.1 (95 % CI 5.1-5.2) years at the time of implantation. 7.5 % (N = 739) of patients had unilateral SNHL and 92.5 % (N = 9124) had bilateral SNHL. Children with bilateral SNHL undergoing CI were significantly younger (5.0 years versus 6.9 years for those with unilateral SNHL, p < .001). There was a statistically significant difference in the percentage of children receiving CI for unilateral versus bilateral SNHL (3.3 % in 2012 to 14.3 % in 2021, p < .001) before and after the FDA changes. CONCLUSIONS: The proportion of CIs placed for unilateral SNHL has increased annually even before 2019 when the FDA expanded its CI indications to include children with unilateral SNHL for the first time.

Effective cochlear implantation for idiopathic hypertrophic pachymeningitis with bilateral profound hearing loss: A case report.

RATIONALE: Hypertrophic pachymeningitis (HP) is a local or diffuse fibrous thickness of the dura mater of the brain or spinal cord, caused by infection or connective tissue disease. Headache is the most common clinical symptom, followed by various cranial nerve disorders such as visual impairment, diplopia, and hearing loss. HP can be classified into secondary and idiopathic. Here, we report a case of bilateral progressive profound sensorineural hearing loss diagnosed in a patient with idiopathic HP, where a cochlear implant was effectively used. PATIENT CONCERNS: The patient was a 77-year-old woman. Hearing loss gradually progressed bilaterally, and magnetic resonance imaging showed a space-occupying lesion with a continuous contrast enhancement in the bilateral internal auditory canals, and diffused dural thickening from the middle to the posterior cranial fossa. DIAGNOSES: A trans-labyrinthine biopsy was conducted, and a definite diagnosis of idiopathic HP was made. Thickening of the dura mater in the bilateral internal auditory canals was thought to cause profound hearing loss. INTERVENTIONS AND OUTCOMES: A cochlear implant was implemented 4 months after biopsy, and a favorable hearing response was obtained postoperatively. LESSONS: This is the first report of a cochlear implant in a patient with idiopathic HP. Cochlear implantation was considered a good treatment for profound hearing loss due to idiopathic HP, which provides a reference for patients to receive timely and correct treatment.

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.

Age and Incidence of Cochlear Implantation in the Pediatric Population With Congenital Bilateral Profound Hearing Loss.

OBJECTIVES: The current study characterizes age and incidence of cochlear implantation among qualifying children with congenital bilateral profound hearing loss in the U.S. STUDY DESIGN: Deidentified cochlear implantation data were acquired from prospectively collected patient registries from two cochlear implant (CI) manufacturers (Cochlear Americas and Advanced Bionics). Children <36 months old were assumed to have congenital bilateral profound sensorineural hearing loss. SETTING: U.S. CI centers. PATIENTS: Children <36 months old who received CIs. INTERVENTIONS: Cochlear implantation. MAIN OUTCOME MEASURES: Age at implantation and incidence. RESULTS: A total of 4,236 children <36 months old underwent cochlear implantation from 2015 to 2019. The median age at implantation was 16 months (interquartile range, 12-24 mo) and did not change significantly during the 5-year study period ( p = 0.09). Patients residing closer to CI centers ( p = 0.03) and treated at higher-volume centers ( p = 0.008) underwent implantation at a younger age. Bilateral simultaneous implantation increased from 38% to 53% of CI surgeries in 2015 and 2019, respectively. Children who received bilateral simultaneous CIs were younger compared with those receiving unilateral or bilateral sequential CIs (median, 14 versus 18 mo; p < 0.001). The incidence of cochlear implantation increased from 7,648 per 100,000 person-years in 2015 to 9,344 in 2019 ( p < 0.001). CONCLUSION: Although the incidence of pediatric CI recipients and the frequency of bilateral simultaneous implantation increased over the study period, age at implantation did not change significantly and far exceeded current Food and Drug Administration (9 mo) and American Academy of Otolaryngology and Head and Neck Surgery position statement (6-12 mo) guidelines.

Cochlear Implantation for Rudimentary Otocysts: Two Case Reports.

OBJECTIVE: Rudimentary otocyst (RO) is characterized by an otic capsule without an internal auditory canal, which is considered a contraindication to cochlear implantation (CI). In this study, we were the first to report two patients with ROs who underwent CI. PATIENT: Two patients (18 months old and 2 years old) presenting with bilateral congenital hearing loss were diagnosed with ROs. INTERVENTION: CI was performed. The transmastoid slotted labyrinthotomy approach was used with customized MED-EL electrode arrays. MAIN OUTCOME MEASURES: Categorical auditory performance, infant-toddler meaningful auditory integration of sound, the speech intelligibility rating, and meaningful use of speech scale. RESULTS: Both children could understand common phrases and had intelligible, connected speech 2 years after CI. CONCLUSION: With proper indication, surgical approach and postoperative training, a child with an RO may benefit from CI.

Bilateral simultaneous cochlear implantation is a safe method of hearing rehabilitation in adults.

PURPOSE: Bilateral cochlear implantation is an effective treatment for patients with bilateral profound hearing loss. In contrast to children, adults mostly choose a sequential surgery. This study addresses whether simultaneous bilateral CI is associated with higher rates of complications compared to sequential implantation. METHODS: 169 bilateral CI surgeries were analyzed retrospectively. 34 of the patients were implanted simultaneously (group 1), whereas 135 patients were implanted sequentially (group 2). The duration of surgery, the incidence of minor and major complications and the duration of hospitalization of both groups were compared. RESULTS: In group 1, the total operating room time was significantly shorter. The incidences of minor and major surgical complications showed no statistically significant differences. A fatal non-surgical complication in group 1 was particularly extensively reappraised without evidence of a causal relationship to the chosen mode of care. The duration of hospitalization was 0.7 days longer than in unilateral implantation but 2.8 days shorter than the combined two hospital stays in group 2. CONCLUSION: In the synopsis of all considered complications and complication-relevant factors, equivalence of simultaneous and sequential cochlear implantation in adults in terms of safety was found. However, potential side effects related to longer surgical time in simultaneous surgery must be considered individually. Careful patient selection with special consideration to existing comorbidities and preoperative anesthesiologic evaluation is essential.

Influence of listening environment on usage patterns in cochlear implant patients with single-sided deafness.

OBJECTIVE: To compare cochlear implant (CI) data logging of patients with single-sided deafness (SSD) and bilateral sensorineural hearing loss (biSNHL) in various acoustic environments and study the implications of data logging on auditory performance. STUDY DESIGN: Retrospective case control study. METHODS: Adult CI patients with SSD or biSNHL from 2010 to 2021 with usage data collected at 3-, 6-, and 12-months following device activation were identified. The CI listening environment was defined as speech in noise, speech in quiet, quiet, music or noise. Auditory performance was measured using the CNC word, AzBio sentence tests and the Tinnitus Handicap Index (THI). RESULTS: 60 adults with SSD or biSNHL were included. CI patients with biSNHL wore their devices more than those with SSD at 3-months post-activation (11.18 versus 8.97 hours/day, p = 0.04), though there were no significant differences at 6-12 months. Device usage was highest in the speech in quiet environment. In SSD CI users, there was a positive correlation (p = 0.03) between device use and CNC scores at 12-months and an improvement in THI scores at 12-months (p = 0.0004). CONCLUSIONS: CI users with SSD and biSNHL have comparable duration of device usage at longer follow-up periods with greatest device usage recorded in speech in quiet environments.

Performance of Sequentially Bilateral Cochlear Implanted Children Who Speak Mandarin.

INTRODUCTION: Cochlear implantation is an effective treatment for children with deafness. Although the binaural effect of bilateral cochlear implantation on sound localization and speech perception in noisy environments has been demonstrated, the outcome and performance predictors of the second cochlear implant (CI2) remain uncertain for patients receiving sequential implantation. This study evaluated the hearing performance between the first cochlear implant (CI1), CI2, and bilateral cochlear implants (CI1+2) among children with sequential bilateral cochlear implantation. METHODS: This single-center retrospective study enrolled 14 children and adolescents aged 8-18 years who underwent sequential bilateral cochlear implantation with a mean interimplant interval of 8.2 years. The Mandarin Lexical Neighborhood Test (M-LNT), the Mandarin Hearing in Noise Test (M-HINT), and the Comprehensive Cochlear Implant Questionnaire (CCIQ) scores of participants were evaluated. Mann-Whitney U tests and Spearman correlation analysis were performed to analyze factors associated with CI2 performance. RESULTS: In the 1-year follow-up period after CI2 implantation, although the M-LNT mean score for CI2 was significantly lower than that for CI1, the M-LNT scores for CI2 and CI1+2 improved significantly over time. In a noisy environment, CI1+2 significantly outperformed CI1 in the M-HINT. The M-LNT score for CI2 was significantly associated with preoperative bimodal fitting, residual hearing of the second implanted ear, and CI2 daily-usage time. Specific to CI2, the CCIQ showed improvement 1 year after CI2 implantation. CONCLUSION: CI2 improved the hearing performance and quality of life of recipients with longer interimplant intervals, especially in noisy environments, and its efficacy was associated with preoperative bimodal fitting and regular daily use.

Robotic cochlear implantation in post-meningitis ossified cochlea.

AIM: To report the experience of an image-guided and navigation-based robot arm as an assistive surgical tool for cochlear implantation in a case with a labyrinthitis ossificans. PATIENT: A 55-years-old man with a history of childhood meningitis whose hearing deteriorated progressively to bilateral profound sensorineural hearing loss. INTERVENTION: Robotic Assisted Cochlear Implant Surgery (RACIS) with a straight flexible lateral wall electrode. PRIMARY OUTCOME MEASURES: Electrode cochlear insertion depth with RACIS with facial recess approach and autonomous inner ear access with full electrode insertion of a flexible straight cochlear implant array. CONCLUSIONS: Intra cochlear ossifications pose a challenge for entering the cochlea and full-length insertion of a cochlear implant. RACIS has shown that computations of radiological images combined with navigation-assisted robot arm drilling can provide efficient access to the inner ear.

Sequential bilateral cochlear implant: long-term speech perception results in children first implanted at an early age.

PURPOSE: The study aims to assess the benefit of sequential bilateral cochlear implantation in children with congenital bilateral profound hearing loss, submitted to the first implant at an early age. METHODS: We enrolled all the bilateral sequential cochlear implanted children who received the first implant within 48 months and the second within 12 years of age at our Institution. The children were submitted to disyllabic word recognition tests and Speech Reception Threshold (SRT) assessment using the OLSA matrix sentence test with the first implanted device (CI1), with the second implanted device (CI2), and with both devices (CIbil). Furthermore, we measured the datalogging of both devices. Then we calculated the binaural SRT gain (b-SRTgain) and checked the correlations between speech perception results and the b-SRTgain with the child's age at CI1 and CI2, DELTA and the datalogging reports. RESULTS: With the bilateral electric stimulation, we found a significant improvement in disyllabic word recognition scores and in SRT. Moreover, the datalogging showed no significant differences in the time of use of CI1 and CI2. We found significant negative correlations between speech perception abilities with CI2 and age at CI2 and DELTA, and between the SRT with CI1 and the b-SRTgain. CONCLUSIONS: From this study we can conclude that in a sequential CI procedure, even if a short inter-implant delay and lower ages at the second surgery can lead to better speech perception with CI2, children can benefit from bilateral stimulation independently of age at the second surgery and the DELTA.

Effects of Bilateral Cochlear Implantation on Binaural Listening Tasks for Younger and Older Adults.

PURPOSE: This study investigated the objective and subjective benefit of a second cochlear implant (CI) on binaural listening tasks of speech understanding in noise and localization in younger and older adults. We aimed to determine if the aging population can utilize binaural cues and obtain comparable benefits from bilateral CI (BIL_CI) when compared to the younger population. METHODS: Twenty-nine adults with severe to profound bilateral sensorineural hearing loss were included. Participants were evaluated in two conditions, better CI (BE_CI) alone and BIL_CI using AzBio and Bamford-Kowal-Bench (BKB) sentence in noise tests. Localization tasks were completed in the BIL_CI condition using a broadband stimulus, low-frequency stimuli, and high-frequency stimuli. A subjective questionnaire was administered to assess satisfaction with CI. RESULTS: Older age was significantly associated with poorer performance on AzBio +5 dB signal-to-noise ratio (SNR) and BKB-speech in noise (SIN); however, improvements from BE_CI to BIL_CI were observed across all ages. In the AzBio +5 condition, nearly half of all participants achieved a significant improvement from BE_CI to BIL_CI with the majority of those occurring in patients younger than 65 years of age. Conversely, the majority of participants who achieved a significant improvement in BKB-SIN were adults >65 years of age. Years of BIL_CI experience and time between implants were not associated with performance. For localization, mean absolute error increased with age for low and high narrowband noise, but not for the broadband noise. Response gain was negatively correlated with age for all localization stimuli. Neither BIL_CI listening experience nor time between implants significantly impacted localization ability. Subjectively, participants report reduction in disability with the addition of the second CI. There is no observed relationship between age or speech recognition score and satisfaction with BIL_CI. CONCLUSION: Overall performance on binaural listening tasks was poorer in older adults than in younger adults. However, older adults were able to achieve significant benefit from the addition of a second CI, and performance on binaural tasks was not correlated with overall device satisfaction. The significance of the improvement was task and stimulus dependent but suggested a critical limit may exist for optimal performance on SIN tasks for CI users. Specifically, older adults require at least a +8 dB SNR to understand 50% of speech postoperatively; therefore, solely utilizing a fixed +5 dB SNR preoperatively to qualify CI candidates is not recommended as this test condition may introduce limitations in demonstrating CI benefit.

Factors affecting phoneme discrimination in children with sequential bilateral cochlear implants.

OBJECTIVES: To investigate the effects of a number of variables on phoneme discrimination (PD) performance in children with sequential bilateral cochlear implants (SeqBiCIs) and compare PD performance between the 2 implantation sides and between children with bilateral cochlear implants (BiCIs) and their age-matched peers with normal hearing (NH). DESIGN: All participants completed the Auditory Speech Sound Evaluation Phoneme Discrimination Test. STUDY SAMPLE: The sample included 23 children with SeqBiCIs as the study group and 23 with NH as the control group. RESULTS: A significant difference was found between the scores of the two groups under the CI1 and CI2 conditions (p = 0.001), CI1 and BiCI conditions (p = 0.002), and CI2 and BiCI conditions (p = 0.001). PD scores with CI1 significantly depend on age at CI1 and duration of bilateral use. PD scores with CI1 were significant predictors of PD performance with CI2. Duration of BiCI use was a significant predictor of PD scores with BiCI. CONCLUSIONS: The age at CI1 and the duration of bilateral cochlear implant use were found to improve phoneme discrimination performance in children with a sequential bilateral cochlear implant. According to the success of the CI1, it is possible to predict the success of CI2 use.

Speech Perception Performance Growth and Benchmark Score Achievement After Cochlear Implantation for Single-Sided Deafness.

OBJECTIVES: Compare speech perception performance growth and benchmark score achievement among adult cochlear implant (CI) recipients with single-sided deafness (SSD) versus bilateral moderate to profound hearing loss. STUDY DESIGN: Retrospective matched cohort analysis. SETTING: Tertiary referral center. PATIENTS: Adults with SSD or bilateral moderate to profound hearing sensorineural hearing loss who underwent cochlear implantation from 2014 to 2019. INTERVENTIONS: Cochlear implantation. MAIN OUTCOME MEASURES: Time-to-benchmark speech perception score (CNC, AzBio in quiet) and speech performance within first postoperative year. RESULTS: Thirty-three SSD patients were matched to 66 bilateral hearing loss patients (referent cohort) for duration of deafness and preoperative ipsilateral CNC scores. Although SSD patients were more likely to achieve benchmark CNC scores more quickly compared with matched referents, this difference did not reach statistical significance (HR 1.72; 95% CI 0.78-3.82; p = 0.18). AzBio scores showed similar trends (HR 1.40; 95% CI 0.66-2.98; p = 0.38). At last follow-up, the SSD cohort had lower CNC (median 54% vs. 62%; p = 0.019) and AzBio scores (median 72% vs. 84%; p = 0.029) compared to the referent cohort. CONCLUSIONS: No significant difference in speech perception performance growth (i.e., time-to-benchmark speech perception score) was identified between SSD and bilateral hearing loss CI recipients, although patients with bilateral hearing loss achieved higher scores in the implanted ear within the first year of follow-up.

Restoration of Deafferentation Reduces Tinnitus, Anxiety, and Depression: A Retrospective Study on Cochlear Implant Patients.

Patients with profound bilateral deafness (BD) are prone to suffering from tinnitus, which further leads to psychological comorbidities and makes it more difficult for patients to communicate with people. This study was aimed at investigating the effect of cochlear implants (CIs) on tinnitus distress and psychological comorbidities in patients with profound BD. This multicenter retrospective study reviewed 51 patients with severe postlingual BD who underwent cochlear implantation; 49 patients underwent unilateral cochlear implantation, and 2 patients underwent bilateral cochlear implantation. The patients were asked to complete all the questionnaires, including the tinnitus handicap inventory (THI), the visual analog scale (VAS) score, the Hospital Anxiety and Depression Scale Questionnaire (HADS), the Categories of Auditory Performance (CAP), and the Speech Intelligibility Rating (SIR), at least 4 months after implantation when the CI was on or off, in approximately May-June 2019. In our study, 94% (48/51) of BD patients suffered from tinnitus before CI, and 77% (37/48) of them suffered from bilateral tinnitus. In addition, 50.9% (26/51) of the CI patients were suffering from anxiety, 52.9% (27/51) of them were suffering from depression (score ≥ 8), and 66.7% (34/51) (27/51) of them were suffering from anxiety or depression. Cochlear implantation could reduce tinnitus more obviously when the CI was on than when the CI was off. Cochlear implantation also reduced anxiety/depression severity. There were significantly positive correlations between tinnitus severity and anxiety/depression severity before and after surgery. Moreover, hearing improvement is positively correlated with reduction level of tinnitus, the better hearing, and the lesser severity of tinnitus. Thus, along with effective restoration of deafferentation, cochlear implantation shows positive therapeutic effects on tinnitus and psychological comorbidities, providing a reference for future clinical and research work.

Bilateral cochlear implantation.

Binaural hearing has certain benefits while listening in noisy environments. It provides the listeners with access to time, level and spectral differences between sound signals, perceived by the two ears. However, single sided deaf (SSD) or unilateral cochlear implant (CI) users cannot experience these binaural benefits due to the acoustic input coming from a single ear. The translational research on bilateral CIs started in the year 1998, initiated by J. Müller and J. Helms from Würzburg, Germany in association with MED-EL. Since then, several clinical studies were conducted by different research groups from across the world either independently or in collaboration with MED-EL. As a result, the bilateral CI has become the standard of care in many countries along with reimbursement by the health care systems. Recent data shows that children particularly, are given high priority for the bilateral CI implantation, most often performed simultaneously in a single surgery, as the binaural hearing has a positive effect on their language development. This article covers the milestones of translational research from the first concept to the widespread clinical use of bilateral CI.