A Consensus to Revise the Minimum Speech Test Battery-Version 3.

PURPOSE: The Minimum Speech Test Battery (MSTB) for adults was introduced in 1996 (Nilsson et al., 1996) and subsequently updated in 2011 (Advanced-Bionics et al., 2011). The MSTB has been widely used by clinicians as a guide for cochlear implant (CI) candidacy evaluations and to document post-operative speech recognition performance. Due to changes in candidacy over the past 10 years, a revision to the MSTB was needed. METHOD: In 2022, the Institute for Cochlear Implant Training (ICIT) recruited a panel of expert CI audiologists to update and revise the MSTB. This panel utilized a modified Delphi consensus process to revise the test battery and to improve its applicability considering recent changes in CI care. RESULTS: This resulted in the MTSB-Version 3 (MSTB-3), which includes test protocols for identifying not only traditional CI candidates but also possible candidates for electric-acoustic stimulation and patients with single-sided deafness and asymmetric hearing loss. The MSTB-3 provides information that supplements the earlier versions of the MSTB, such as recommendations of when to refer patients for a CI, recommended patient-reported outcome measures, considerations regarding the use of cognitive screeners, and sample report templates for clinical documentation of pre- and post-operative care. Electronic versions of test stimuli, along with all the materials described above, will be available to clinicians via the ICIT website (https://www.cochlearimplanttraining.com). CONCLUSION: The goal of the MSTB-3 is to be an evidence-based test battery that will facilitate a streamlined standard of care for adult CI candidates and recipients that will be widely used by CI clinicians.

Preliminary Evidence to Support a De-Escalated Cochlear Implant Programming Paradigm for New Adult Recipients: A Systematic Review.

Background: No standard schedule for cochlear implant (CI) programming has been developed, and common practices may have CI recipients seen in excess of what is necessary. The objective of this study was to review evidence for a de-escalated, evidence-based schedule for adult CI programming. Methods: Systematic review was undertaken in March 2023 of PubMed, Scopus, and CINAHL databases using the Preferred Reporting Items for Systemic Reviews and Meta-analyses (PRISMA) guidelines. Studies were included if (1) they evaluated an evidence-based programming/follow-up schedule in new adult CI patients or (2) they evaluated programming or outcomes in a longitudinal fashion such that they could inform CI follow-up strategies. Level of evidence was evaluated using the LEGEND evidence assessment tool. Results: Our review identified 940 studies. After screening with a priori inclusion criteria, 18 studies were ultimately included in this review. Of these, 2 demonstrated feasibility of de-escalated approaches to new adult CI programming. The remainder presented longitudinal speech and programming parameter data that demonstrated relative stability of both categories by 3 to 6 months post-activation. Conclusions: Overall, there is a paucity of literature evaluating any form of evidence-based CI programming or follow-up. Most applicable data derive from longitudinal outcomes featured in studies of other CI features, with only a handful of studies directly evaluating CI programming strategies over time. However, stability in outcomes and programming detailed in the available data supports consideration of a de-escalated programming paradigm that could primarily limit programming to the very early post-activation period (before 3 to 6 months) to enhance patient care and reduce operational strains on cochlear implant programs.

Catchment Profile of Large Cochlear Implant Centers in the United States.

OBJECTIVE: To characterize the catchment area and patient profile of large cochlear implant (CI) centers in the United States. STUDY DESIGN: Multi-institutional retrospective case series. SETTING: Tertiary referral CI centers. METHODS: Patients who underwent CI surgery at 7 participating CI centers between 2015 and 2020 were identified. Patients' residential zip codes were used to approximate travel distances and urban vs rural residential areas. RESULTS: Over the 6-year study period (2015-2020), 6313 unique CI surgical procedures occurred (4529 adult, 1784 pediatric). Between 2015 and 2019, CI procedures increased by 43%. Patients traveled a median 52 miles (interquartile range, 21-110) each way; patients treated at rural CI centers traveled greater distances vs those treated at urban centers (72 vs 46 miles, P < .001). Rural residents represented 61% of the patient population and traveled farther than urban residents (73 vs 24 miles, P < .001). Overall, 91% of patients lived within a 200-mile radius of the institution, while 71% lived within a 100-mile radius. In adults, multiple regression analysis redemonstrated an association between greater travel distances and (1) older age at the time of CI and (2) residential rural setting (both P < .001, r2 = 0.2). CONCLUSIONS: While large CI centers serve geographically dispersed populations, most patients reside within a 200-mile radius. Strategies to expand CI utilization may leverage remote programming, telemedicine, and strategic placement of new centers and satellite clinics to ameliorate travel burden.

Decoding Billing Practices in Cochlear Implant Programs.

OBJECTIVES: The purpose of this study was to examine current cochlear implant (CI) billing practices across CI audiologists in the United States, to determine if CI audiologists are following the National Correct Coding Initiative (NCCI) edits, and to assess the CI audiologist's exposure to billing education. DESIGN: A 48-question survey was electronically distributed to and completed by audiologists who bill for CI services. Demographic data including work setting, population served, years of experience, number of CI patients managed per week, and exposure to billing education were collected. Data were analyzed to identify codes and modifiers used to bill for commonly performed CI procedures such as unilateral and bilateral CI programming, preoperative and postoperative testing, and objective measures. RESULTS: Data were obtained from 96 audiologists. The majority (86.3%, n = 82) of respondents agreed or strongly agreed they understand billing and coding practices for cochlear implants and 94.7% (n = 89) rated themselves as somewhat to highly efficient when performing these practices. Only 16.8% (n = 16) of respondents reported receiving formal training for practice management, and half of the respondents (51.1%, n = 48) reported unfamiliarity with national billing guidelines. Those who received formal training reported higher billing efficiency. Wide variability was seen for various billing scenarios. Billing questions were presented, and answers were coded as correct or incorrect based on the NCCI edits. Respondents who reported higher agreement with understanding billing and who received formal training scored better on common billing questions related to the NCCI edits. CONCLUSIONS: Most CI audiologists rated themselves as efficient in billing; however, wide variance in billing practices was observed. Incorporating practice management and current billing education into daily practice and into audiology training programs is essential to clinic efficiency, practice management, and CI program viability. CI audiologists should be knowledgeable about appropriate billing practices to ensure long-term sustainability of programs.

Pediatric Bilateral Sensorineural Hearing Loss: Minimum Test Battery and Referral Criteria for Cochlear Implant Candidacy Evaluation.

Among the various cochlear implant systems approved by the Food and Drug Administration, current labeling for pediatric usage encompasses (1) bilateral profound bilateral sensorineural hearing loss in children aged 9 to 24 months and bilateral severe to profound sensorineural hearing loss in children older than 2 years; (2) use of appropriately fitted hearing aids for 3 months (this can be waived if there is evidence of ossification); and (3) demonstration of limited progress with auditory, speech, and language development. Pediatric guidelines require children to have significantly worse speech understanding before qualifying for cochlear implantation. The early years of life have been shown to be critical for speech and language development, and auditory deprivation is especially detrimental during this crucial time.Level of evidence: 2.

Determining Cochlear Implant Candidacy in Adults: Limitations, Expansions, and Opportunities for Improvement.

The safety, efficacy, and success of cochlear implants (CIs) are well established and have led to changes in criteria used by clinicians to determine who should receive a CI. Such changes in clinical decision-making have out-paced the slower-occurring changes that have taken place with regulatory bodies' and insurers' indications. We review the historical development of indications for CIs, including those of the U.S. Food and Drug Administration (FDA), Medicare, Medicaid, and private insurers. We report on expansion to include patients with greater residual hearing, such as those who receive Hybrid and EAS devices, and report on recent FDA approvals that place less emphasis on the patient's best-aided condition and greater emphasis on the ear to be treated. This includes expansion of CIs to patients with single-side deafness and asymmetric hearing loss. We review changes in the test materials used to determine candidacy, including transition from sentences in quiet to sentences in noise to the recent use of monosyllabic words and cognitive screening measures. Importantly, we discuss the recent trend to recommend CIs despite a patient not meeting FDA or insurers' indications (a practice known as "off-label"), which serves as attestation that current indications need to be updated.

Using the electrically-evoked compound action potential (ECAP) interphase gap effect to select electrode stimulation sites in cochlear implant users.

Studies in cochlear implanted animals show that the IPG Effect for ECAP growth functions (i.e., the magnitude of the change in ECAP amplitude growth function (AGF) slope or peak amplitude when the interphase gap (IPG) is increased) can be used to estimate the densities of spiral ganglion neurons (SGNs) near the electrode stimulation and recording sites. In humans, the same ECAP IPG Effect measures correlate with speech recognition performance. The present study examined the efficacy of selecting electrode sites for stimulation based on the IPG Effect, in order to improve performance of CI users on speech recognition tasks. We measured the ECAP IPG Effect for peak amplitude in adult (>18 years old) CI users (N= 18 ears), and created experimental programs to stimulate electrodes with either the highest or lowest ECAP IPG Effect for peak amplitude. Subjects also listened to a program without any electrodes deactivated. In a subset of subject ears (11/18), we compared performance differences between the experimental programs to post-operative computerized tomography (CT) scans to examine underlying factors that might contribute to the efficacy of an electrode site-selection approach. For sentences-in-noise, average performance was better when subjects listened to the experimental program that stimulated electrodes with the highest rather than the lowest IPG Effect for ECAP peak amplitude. A similar pattern was noted for transmission and perception of consonant place cues in a consonant recognition task. However, on average, performance when listening to a program with higher IPG Effect values was equal to that when listening with all electrodes activated. Results also suggest that scalar location (scala tympani or vestibuli) should be considered when using an ECAP-based electrode site-selection procedure to optimize CI performance.

Investigation of an Outcomes-Driven, Computer-Assisted Approach to CI Fitting in Newly Implanted Patients.

OBJECTIVE: To evaluate the efficacy of outcomes received by newly implanted cochlear implant recipients when an outcomes-driven, computer-assisted approach to cochlear implantation fitting was used. This approach, referred to as "Fitting to Outcome eXpert," or FOX, was developed by Otoconsult in Antwerp, Belgium. DESIGN: Thirty-one newly implanted subjects participated in a nonrandomized, single-subject, repeated measures design that involved a within-subject comparison of preoperative and postoperative speech recognition scores. Sound processors for all subjects were programmed using the FOX software that utilized the evidence-based results of various psychoacoustic tests to adjust MAP parameters and improve performance. Additionally, mean word and sentence recognition scores obtained by the subjects programmed with FOX were compared to results obtained by newly implanted patients enrolled in the Nucleus CI532 clinical trial whose devices were programmed using traditional methods. RESULTS: Subjects whose sound processors were programmed using FOX obtained a mean 6-month postactivation Consonant Nucleus Consonant word score of 60.2% correct. This represented an improvement of 46% age points when mean preactivation and postactivation scores were compared and represented a statistically significant change in score (p < 0.001). This mean score is similar to the mean 6-month Consonant Nucleus Consonant Word score of 61% obtained by 96 subjects enrolled in the Nucleus CI532 trial. Additionally, subjects in this study obtained a mean 6-month postactivation AzBio Sentence score of 42.7% correct when stimuli were presented at 65 dBA using a +10 signal-to-noise ratio. This score is also similar to the mean score of 43% obtained by 96 subjects enrolled in the Nucleus CI532 trial using the same test material and signal-to-noise ratio. Patients enrolled in this study attended 43% fewer programming appointments than the number reported by cochlear implantation centers in recent surveys of clinical care. CONCLUSION: The results of this study support the use of an outcomes-driven, computer-assisted approach to supplement the management of newly implanted cochlear implant recipients. Subjects whose devices were programmed using such an approach demonstrated mean postoperative word in quiet and sentence in noise scores comparable to those obtained by subjects in the Nucleus CI532 clinical trial whose devices were programmed using traditional programming techniques. Use of this approach positively impacted patient care by reducing the number of postoperative visits needed to optimize sound processor programs, simplified patient testing via the use of direct streaming, and ensured that patients received consistent programming of their sound processor, regardless of the location where the programming was performed.

Assessment of Cochlear Implants for Adult Medicare Beneficiaries Aged 65 Years or Older Who Meet Expanded Indications of Open-Set Sentence Recognition: A Multicenter Nonrandomized Clinical Trial.

Importance: Current indications for Medicare beneficiaries to receive a cochlear implant are outdated. Multichannel cochlear implant systems may be effective when provided to Medicare beneficiaries using expanded indications. Objective: To examine the effectiveness of cochlear implants, as measured by improvement on the AzBio Sentence Test, for newly implanted Medicare beneficiaries who meet the expanded indications of an AzBio Sentence Test score of 41% to 60% in their best-aided condition. Design, Setting, and Participants: A multicenter nonrandomized trial examined preoperative and postoperative speech recognition, telephone communication, hearing device benefit, health utility, and quality of life for 34 participants enrolled at 8 different centers who received a cochlear implant between September 17, 2014, and July 10, 2018. All participants were 65 years or older, had bilateral moderate to profound hearing loss, and had a best-aided preoperative AzBio Sentence Test score in quiet of 41% to 60%. Analysis was performed on an intention-to-treat basis. Statistical analysis of final results took place from July 29 to October 1, 2019. Intervention: Multichannel cochlear implants. Main Outcomes and Measures: The study examined the a priori hypothesis that the cochlear implant would improve the AzBio Sentence Test score in the best-aided condition by 25% or more and in the implanted ear-alone condition by 30% or more. The study additionally examined word and telephone recognition and examined device benefit, health utility, and quality of life. Results: A total of 34 participants received a cochlear implant; 31 (23 men [74%]; median age, 73.6 years [range, 65.7-85.1 years]) completed testing through the 6-month evaluation, and 29 completed testing through the 12-month evaluation. Median preoperative AzBio Sentence Test scores were 53% (range, 26%-60%) for the best-aided condition and 24% (range, 0%-53%) for the cochlear implant-alone condition; median scores 12 months after implantation improved to 89% (range, 36%-100%) for the best-aided condition and 77% (range, 13%-100%) for the cochlear implant-alone condition. This outcome represents a median change of 36% (range, -22% to 75%) for the best-aided condition (lower bound of 1-sided 95% CI, 31%) and a median change of 53% (range, -15% to 93%) for the cochlear implant-alone condition (lower bound of 1-sided 95% CI, 45%). Conclusions and Relevance: Intervention with a cochlear implant was associated with improved sentence, word, and telephone recognition in adult Medicare beneficiaries whose preoperative AzBio Sentence Test scores were between 41% and 60%. These findings support expansion of the Center for Medicare & Medicaid current indications for cochlear implants. Trial Registration: ClinicalTrials.gov Identifier: NCT02075229.

Development of a 60/60 Guideline for Referring Adults for a Traditional Cochlear Implant Candidacy Evaluation.

OBJECTIVE: To evaluate the effectiveness of a 60/60 referral guideline for identifying patients who should be referred for a cochlear implant candidacy evaluation (CICE), which states patients should be referred if they demonstrate a best ear unaided monosyllabic word score less than or equal to 60% correct and if they demonstrate an unaided pure-tone average in their better ear that is greater than or equal to 60 dB HL. STUDY DESIGN: Retrospective review of data from adults who participated in a CICE. SETTING: A single tertiary medical facility. PATIENTS: Five hundred twenty-nine patients who participated in a CICE. INTERVENTION: CICEs included unaided threshold assessment, unaided speech recognition, and aided word and sentence testing. MAIN OUTCOME MEASURE: Ninety-five percent of patients who met traditional indications for a cochlear implant (n = 250) had a pure-tone average that was greater than or equal to 60 dB, while 92% had a better ear unaided monosyllabic word score that was less than or equal to 60%. RESULTS: If used as a screening measure, the 60/60 measure resulted in a 96% detection rate and a 34% false-positive rate for identifying adults who would meet traditional indications for a cochlear implant. CONCLUSIONS: Hearing professionals should consider referring patients for a CICE when they meet the 60/60 guideline. It is hoped that provision of this guideline will result in greater numbers of adults being referred for CICEs, improving access to cochlear implants for patients who may benefit from this important technology.

Effects of Electrode Location on Estimates of Neural Health in Humans with Cochlear Implants.

There are a number of psychophysical and electrophysiological measures that are correlated with SGN density in animal models, and these same measures can be performed in humans with cochlear implants (CIs). Thus, these measures are potentially applicable in humans for estimating the condition of the neural population (so called "neural health" or "cochlear health") at individual sites along the electrode array and possibly adjusting the stimulation strategy in the CI sound processor accordingly. Some measures used to estimate neural health in animals have included the electrically evoked compound potential (ECAP), psychophysical detection thresholds, and multipulse integration (MPI). With regard to ECAP measures, it has been shown that the change in the ECAP response as a function of increasing the stimulus interphase gap ("IPG Effect") also reflects neural density in implanted animals. These animal studies have typically been conducted using preparations in which the electrode was in a fixed position with respect to the neural population, whereas in human cochlear implant users, the position of individual electrodes varies widely within an electrode array and also across subjects. The current study evaluated the effects of electrode location in the implanted cochlea (specifically medial-lateral location) on various electrophysiological and psychophysical measures in eleven human subjects. The results demonstrated that some measures of interest, specifically ECAP thresholds, psychophysical detection thresholds, and ECAP amplitude-growth function (AGF) linear slope, were significantly related to the distances between the electrode and mid-modiolar axis (MMA). These same measures were less strongly related or not significantly related to the electrode to medial wall (MW) distance. In contrast, neither the IPG Effect for the ECAP AGF slope or threshold, nor the MPI slopes were significantly related to MMA or MW distance from the electrodes. These results suggest that "within-channel" estimates of neural health such as the IPG Effect and MPI slope might be more suitable for estimating nerve condition in humans for clinical application since they appear to be relatively independent of electrode position.

Health related quality of life in adolescent cochlear implant users.

Objective: Children with significant hearing loss (HL) are at risk for lower self-esteem and lower perceived quality of life (QoL). This study examined how self-reported QoL of adolescents cochlear implant (CI) users compared to that of adolescents with normal hearing, and examined if factors such as socioeconomic status (SES) and communication methodology affect QoL and speech recognition. Methods: Forty-three adolescent CI users completed a 34-item questionnaire that included questions adapted from the QoL of Deaf or Hard-of-Hearing Youth questionnaire (Seattle Quality of Life Group SEAQOL. 2010 Quality of life of deaf or hard-of-hearing youth (YQOL-DHH). Seattle, Washington) and from the Kidscreen-10 Index (The KIDSCREEN Group, Europe, 2006, the KIDSCREEN questionnaires - quality of life questionnaires for children and adolescents handbook. Lengerich: Pabst Science Publishers. All subjects received their first CI prior to the age of 5, and ranged in age from 10-17 years at the time of survey completion. Results: Adolescents with CIs demonstrated self-reported QoL scores similar to children with normal hearing. Lower SES and communication mode appear to influence speech recognition, and also appear to impact self-reported QoL in different ways. Conclusions: Examination of communication outcomes, along with other factors that influence QoL, such as SES, will help clinicians identify children at risk for low QoL. Such identification will help generate appropriate referrals to enhance QoL in adolescent CI users.

Communication Mode and Speech and Language Outcomes of Young Cochlear Implant Recipients: A Comparison of Auditory-Verbal, Oral Communication, and Total Communication.

OBJECTIVE: To evaluate the effect of communication mode on the spoken language outcomes of children who received a cochlear implant. STUDY DESIGN: Retrospective analysis of postoperative speech and language and reading scores for children who received a cochlear implant and used three different modes of communication: auditory-verbal (AV) (n = 39), oral communication (OC) (n = 107), and total communication (TC) (n = 57). SETTING: A single tertiary cochlear implant clinic. PATIENTS: All children received their cochlear implant before the age of 5 years, had no known cochlear anomaly or cognitive delay that would affect their outcome with the CI, and had established consistent use of their respective communication methodology. INTERVENTION: Rehabilitation varied depending on the selected communication methodology. Data were collected during routine postoperative speech and language evaluations. MAIN OUTCOME MEASURES: Receptive and expressive language, reading comprehension, and speech intelligibility scores obtained up to 7 years post-activation of a cochlear implant. RESULTS: All groups showed improvements over time. Linear mixed model analyses indicated scores obtained by children in the AV group were significantly higher than mean scores obtained by children in the other groups on most test measures at most post-implant intervals. Significantly greater numbers of children in the AV group obtained standard scores within normal limits than children in the OC and TC groups. CONCLUSIONS: These findings support the use of the auditory-verbal communication approach to facilitate development of age-appropriate speech and language and literacy skills in profoundly deaf children.

Datalogging Statistics and Speech Recognition During the First Year of Use in Adult Cochlear Implant Recipients.

OBJECTIVE: To examine device datalogging characteristics and postoperative speech recognition performance in adult cochlear implant (CI) recipients. STUDY DESIGN: Retrospective study examining datalogging characteristics throughout the first year of device use and postoperative speech recognition outcomes measured at 1 year. PATIENTS: One hundred seventy-seven adults who received a Cochlear CI. MAIN OUTCOME MEASURES: Average values for environmental scene classification (hours of device use per day, and percent of hours per day in quiet, noise, and speech) as reported by Cochlear datalogging over the first year of device use. Speech recognition was assessed at 1 year postactivation. RESULTS: During the first year of devices use, CI listeners >80 years of age used their device significantly less (average = 10.97 h/d) than the youngest adult listeners (18-30 yrs), who used their device an average of 13.29 hours/d. There was no consistent effect of age on the number of hours a CI user listened to speech in noise each day. Correlational and regression analyses suggest that the number of average hours of device use is the primary factor that accounts for variance observed in postoperative consonant-nucleus-consonant word scores. CONCLUSION: Results suggest that the average number of hours listening to speech in noise is not related to postoperative performance, but the average number of hours of device use per day is correlated with postoperative performance. Further research is needed to determine if these findings are merely correlational or causal in nature.

Effects of electrode deactivation on speech recognition in multichannel cochlear implant recipients.

OBJECTIVES: The objective of the current study is to evaluate how speech recognition performance is affected by the number of active electrodes that are turned off in multichannel cochlear implants. Several recent studies have demonstrated positive effects of deactivating stimulation sites based on an objective measure in cochlear implant processing strategies. Previous studies using an analysis of variance have shown that, on average, cochlear implant listeners' performance does not improve beyond eight active electrodes. We hypothesized that using a generalized linear mixed model would allow for better examination of this question. METHODS: Seven peri- and post-lingual adult cochlear implant users (eight ears) were tested on speech recognition tasks using experimental MAPs which contained either 8, 12, 16 or 20 active electrodes. Speech recognition tests included CUNY sentences in speech-shaped noise, TIMIT sentences in quiet as well as vowel (CVC) and consonant (CV) stimuli presented in quiet and in signal-to-noise ratios of 0 and +10 dB. RESULTS: The speech recognition threshold in noise (dB SNR) significantly worsened by approximately 2 dB on average as the number of active electrodes was decreased from 20 to 8. Likewise, sentence recognition scores in quiet significantly decreased by an average of approximately 12%. DISCUSSION/CONCLUSION: Cochlear implant recipients can utilize and benefit from using more than eight spectral channels when listening to complex sentences or sentences in background noise. The results of the current study suggest a conservative approach for turning off stimulation sites is best when using site-selection procedures.

Clinical Outcomes of the Cochlear™ Nucleus(®) 5 Cochlear Implant System and SmartSound™ 2 Signal Processing.

BACKGROUND: While published data exist regarding cochlear implant (CI) outcomes from large academic programs, evidence of benefit based on national, multicenter clinical trials is needed for information regarding typical patient outcomes of devices implanted by U.S. centers representing larger academic to smaller hospital-based programs. PURPOSE: This nationwide trial evaluated outcomes in a group of newly implanted adult recipients of the Cochlear™ Nucleus(®) 5 CI system and SmartSound™ 2 signal processing. Unlike previous clinical trials, the AzBio sentence test was used and represents recent transition in our field to use of more challenging test materials. It was hypothesized that (1) speech perception scores in quiet with SmartSound™ 2 signal processing would not be statistically different from previous-generation devices; (2) speech perception scores in noise with SmartSound™ 2 signal processing would be better with enhanced microphone directionality; (3) speech perception scores in noise will be better with the preferred SmartSound™ 2 program for listening in noise; and (4) cochlear implantation would improve quality of life as assessed by the updated Health Utility Index Mark 3 (HUI3). A secondary purpose was to examine the relationships among the current and previously used speech perception tests of the Minimum Speech Test Battery (MSTB). It was hypothesized that speech perception scores within the same test interval would show predictive relationships. RESEARCH DESIGN: Prospective, single-arm, repeated-measures study across 13 CI centers in the United States between February 2010 and June 2012. The participating centers ranged from larger academic to smaller hospital-based programs to accurately represent the diversity of programs in the United States. STUDY SAMPLE: Participants were 38 postlingually deafened adult CI candidates. DATA COLLECTION AND ANALYSIS: Primary measures were Consonant-Nucleus-Consonant (CNC) words in quiet and the AzBio Sentence Test in Quiet (AzBioQ) and in Noise (AzBioN) tested at preoperative, and 3-, 6-, and 12-mo postactivation intervals. Quality of life was measured with the HUI3. For the secondary objective, statistical analyses were performed to investigate the predictive properties between current and previously used MSTB tests. RESULTS: Mean CNC scores were significantly higher compared to the Nucleus(®) 24 Contour™ at 3 mo (p < 0.05) postactivation and showed no difference compared to the Nucleus(®) Freedom™ at 6 mo postactivation. Both SmartSound™ 2 FOCUS and NOISE programs provided significant improvements in performance in noise over the EVERYDAY program (p < 0.001), and performance with the FOCUS program was significantly better compared to the NOISE program (p < 0.001). Speech perception in noise was not related to patients' subjective program preferences. Quality-of-life outcomes showed significant improvements from the preoperative to 6-mo postactivation interval (p < 0.05-0.001). Strong and significant correlations were found between preoperative CNC and AzBioQ and preoperative Hearing-in-Noise Test sentences in Quiet (HINTQ) and AzBioQ. At 12-mo postactivation, there were strong and highly significant correlations between CNC and AzBioQ, HINTQ and AzBioQ, and Hearing-in-Noise Test sentences in Noise and AzBioN (all p < 0.001). CONCLUSIONS: Results of this national clinical trial showed significant improvements in speech perception and quality of life following cochlear implantation. SmartSound™ 2 signal processing features showed a significant benefit of FOCUS when listening in noise, although preference of signal processing feature did not correlate with performance. Significant correlations were observed between speech perception tests. The findings of this study can be applied in clinical assessment, programming, and follow-up for CI candidates and recipients.

Importance of cochlear health for implant function.

Amazing progress has been made in providing useful hearing to hearing-impaired individuals using cochlear implants, but challenges remain. One such challenge is understanding the effects of partial degeneration of the auditory nerve, the target of cochlear implant stimulation. Here we review studies from our human and animal laboratories aimed at characterizing the health of the implanted cochlea and the auditory nerve. We use the data on cochlear and neural health to guide rehabilitation strategies. The data also motivate the development of tissue-engineering procedures to preserve or build a healthy cochlea and improve performance obtained by cochlear implant recipients or eventually replace the need for a cochlear implant. This article is part of a Special Issue entitled .

The role of age on cochlear implant performance, use, and health utility: a multicenter clinical trial.

OBJECTIVE: To use data obtained in a multicenter clinical trial to evaluate factors affecting performance with an implant, with special emphasis on the effect of age on performance. STUDY DESIGN AND SETTING: Post hoc analyses of data collected during a multicenter prospective study to evaluate performance with a recently introduced cochlear implant (CI) system conducted at 13 academic centers in the United States. Subjects participated in speech recognition testing in quiet and noise and completed questionnaires regarding health utility and processor use. PATIENTS: Thirty-eight adults with moderate to profound hearing loss who ranged in age from 18 to 89 years. Subjects were divided into younger (<65 yr, n = 20) and older (≥65 yr, n = 18) groups for the analyses. INTERVENTION: All subjects received a multichannel CI system. Preimplant to postimplant change in speech recognition was evaluated for each group, and the performance of the two groups was compared. Postimplant performance of older subjects who scored greater than 40% preimplant on HINT (Hearing in Noise Test) sentences was also evaluated. Linear regression was used to further evaluate the effects of variables on outcomes. RESULTS: Both younger and older subjects demonstrated significant improvement in speech recognition and hearing health utility after receiving a CI, and differences between groups were insignificant. Older subjects who scored greater than 40% preoperatively on HINT sentences demonstrated a significant improvement in speech recognition. CONCLUSION: Both older and younger patients can receive significant improvement in speech recognition and health utility after receiving a CI.

Using temporal modulation sensitivity to select stimulation sites for processor MAPs in cochlear implant listeners.

Previous studies in our laboratory showed that temporal acuity as assessed by modulation detection thresholds (MDTs) varied across activation sites and that this site-to-site variability was subject specific. Using two 10-channel MAPs, the previous experiments showed that processor MAPs that had better across-site mean (ASM) MDTs yielded better speech recognition than MAPs with poorer ASM MDTs tested in the same subject. The current study extends our earlier work on developing more optimal-fitting strategies to test the feasibility of using a site-selection approach in the clinical domain. This study examined the hypothesis that revising the clinical speech processor MAP for cochlear implant (CI) recipients by turning off selected sites that have poorer temporal acuity and reallocating frequencies to the remaining electrodes would lead to improved speech recognition. Twelve CI recipients participated in the experiments. We found that site selection procedure based on MDTs in the presence of a masker resulted in improved performance on consonant recognition and recognition of sentences in noise. In contrast, vowel recognition was poorer with the experimental MAP than with the clinical MAP, possibly due to reduced spectral resolution when sites were removed from the experimental MAP. Overall, these results suggest a promising path for improving recipient outcomes using personalized processor-fitting strategies based on a psychophysical measure of temporal acuity.

Across-site patterns of modulation detection: relation to speech recognition.

The aim of this study was to identify across-site patterns of modulation detection thresholds (MDTs) in subjects with cochlear implants and to determine if removal of sites with the poorest MDTs from speech processor programs would result in improved speech recognition. Five hundred millisecond trains of symmetric-biphasic pulses were modulated sinusoidally at 10 Hz and presented at a rate of 900 pps using monopolar stimulation. Subjects were asked to discriminate a modulated pulse train from an unmodulated pulse train for all electrodes in quiet and in the presence of an interleaved unmodulated masker presented on the adjacent site. Across-site patterns of masked MDTs were then used to construct two 10-channel MAPs such that one MAP consisted of sites with the best masked MDTs and the other MAP consisted of sites with the worst masked MDTs. Subjects' speech recognition skills were compared when they used these two different MAPs. Results showed that MDTs were variable across sites and were elevated in the presence of a masker by various amounts across sites. Better speech recognition was observed when the processor MAP consisted of sites with best masked MDTs, suggesting that temporal modulation sensitivity has important contributions to speech recognition with a cochlear implant.