Cochlear (Switzerland)

Objective Treatment options for patients with single-sided deafness (SSD) are: conventional contralateral routing of signal (CROS) hearing aid, bone conduction implant (BCI) and cochlear implant (CI). Only a CI allows restoration of binaural hearing. We compare outcomes with CROS and BCD to CI. Methods Outcome measures are assessed pre- and postoperatively 1, 6 and 12 months after activation of CI. Twelve SSD patients participate in the study. All patients completed the 6m examinations, and 10patients the 12m examinations, 2 patients opted out from the 12m visit due to personal time constraints. Speech reception thresholds (SRT) unaided and CI-aided are measured for two different noises (Olnoise and 2-talker babble noise (TTBN)) in 5 different presentation conditions (SSSDNAH, S0NSSD, S0N0, S0NAH, SAHNSSD). Thresholds are obtained using a modified Oldenburg sentence test (OLSA). Results: Twelve months after CI activation, patients performed much better with CI than preoperatively unaided: SRT improvements in TTBN revealed a mean head shadow effect of 9.7 dB (for SSSDNAH), a mean summation effect of 5.1 dB (for S0N0), and a mean squelch effect of 5.7 dB (for S0NSSD). The use of the CI was favorable in all tested presentation conditions, even in SAHNSSD with a mean SRT improvement of 4.9 dB. Localization ability and tinnitus had improved significantly by 12m. Conclusion Our results show benefits in speech comprehension in noise with CI in all five different presentation conditions revealing the presence of head shadow effect as well as binaural summation and squelch effects. Benefits in localization ability and tinnitus improvement are significant.

Our sense of vision permanently captures, transmits and interprets enormous amounts of visual information. The amount of visual information that can be transmitted to the brain by the means of visual prosthesis will be severely limited and thus also limit the rehabilitation prospects of such devices. While several parameters contribute to the information content of visual stimuli, this chapter concentrates essentially on spatial resolution.

New technology in the Freedom® speech processor for cochlear implants was developed to improve how incoming acoustic sound is processed; this applies not only for new users, but also for previous generations of cochlear implants. AimTo identify the contribution of this technology – the Nucleus 22® – on speech perception tests in silence and in noise, and on audiometric thresholds. MethodsA cross-sectional cohort study was undertaken. Seventeen patients were selected. The last map based on the Spectra® was revised and optimized before starting the tests. Troubleshooting was used to identify malfunction. To identify the contribution of the Freedom® technology for the Nucleus22®, auditory thresholds and speech perception tests were performed in free field in soundproof booths. Recorded monosyllables and sentences in silence and in noise (SNR = 0dB) were presented at 60 dBSPL. The nonparametric Wilcoxon test for paired data was used to compare groups. ResultsFreedom® applied for the Nucleus22® showed a statistically significant difference in all speech perception tests and audiometric thresholds. ConclusionThe reedom® technology improved the performance of speech perception and audiometric thresholds of patients with Nucleus 22®.

Objective: To determine whether new technology for intraoperative evoked compound action potential (ECAP) threshold measurements—the CR120 Intraoperative Remote Assistant device—is comparable to the existing Custom Sound® clinical system, as well as assess test-retest accuracy of the systems. Design: Within subject, repeated measures comparative design. Study sample: ECAP data were collected from 81 pediatric subjects (41 females and 40 males). Results: The average ECAP threshold measurement time for the Custom Sound system was 6.2 minutes (SD = 1.0) versus 4.8 minutes (SD = 0.7) for the CR120 device. ECAP thresholds measured with Custom Sound and the CR120 device had an average Pearson product-moment correlation coefficient for all electrodes (N = 1724) of 0.92, p < 0.01; an average mean absolute difference of 6 CLs (SD = 6); and a 95% confidence interval of − 1 to 1 CLs. The test-retest results for Custom Sound and the CR120 device are also included. Conclusion: A significant reduction in the measurement time for ECAP thresholds was noted with the CR120 device. Furthermore, ECAP thresholds measured with the CR120 device are equivalent to Custom Sound within a clinically acceptable range.

Custom Sound EP™ (CSEP) is an advanced flexible software tool dedicated to recording of electrically evoked compound action potentials (ECAPs) in Nucleus® recipients using Neural Response Telemetry™ (NRT™). European multi-centre studies of the Freedom™ cochlear implant system confirmed that CSEP offers tools to effectively record ECAP thresholds, amplitude growth functions, recovery functions, spread of excitation functions, and rate adaptation functions and an automated algorithm (AutoNRT™) to measure threshold profiles. This paper reports on rate adaptation measurements. Rate adaptation of ECAP amplitudes can successfully be measured up to rates of 495 pulses per second (pps) by repeating conventional ECAP measurements and over a wide range of rates up to 8000 pps using the masked response extraction technique. Rate adaptation did not show a predictable relationship with speech perception and coding strategy channel rate preference. The masked response extraction method offers opportunities to study long-term rate adaptation with well-defined and controlled stimulation paradigms.

The goal of this study is to ascertain worldwide experience with bilateral cochlear implantation (BCI) with regard to patient demographics, trends in provision of BCI to adult and child patient populations, differences and similarities in BCI candidacy criteria, diagnostic requirements, and treatment approaches among clinicians in high-volume cochlear implant centers. Retrospective/prospective. : An electronic survey consisting of 59 mainly multiple-choice questions was developed for online completion. It examined the implant experience and clinical opinion of expert cochlear implant (CI) centers worldwide on the indications, motivations, and contraindications for adult and pediatric, simultaneous and sequential BCI candidacy. Centers were chosen to complete the survey based on their known reputation as a center of excellence. Patient demographics were queried for two time periods to elucidate trends: 2006 and prior, and for the year 2007. Seventy-one percent (25/35) of the CI clinics approached completed the survey. Collectively, these 25 clinics represent experience with approximately 23,200 CI users globally, representing 15% of the total estimated CI population worldwide. The total number of BCI surgeries reflected in their experience (2,880) represents 36% of the estimated number worldwide as of December 2007. Cumulatively to the end of 2007, 70% of all BCI surgeries have occurred in children, with the 3- to 10-year-old age group having the highest representation (33% of all BCIs), followed in order by adults (30%), children under 3 years of age (26%), and children between 11 and 18 years of age (11%). Seventy-two percent of all BCI surgeries were performed sequentially (70% of children, 76% of adults). Children <3 years of age represent the only age group of all patients in which simultaneous surgeries predominate (58% simultaneous). For all other age groups, sequential surgeries far outnumber simultaneous (3-10 years, 84% sequential; 11-18 years, 94% sequential; adults, 76% sequential). Prior to January 2007, 68% of BCIs were performed in children. This increased to 79% for the year 2007 (P < .001). With regard to children only, a change is apparent over time in terms of the age group making up the majority of pediatric BCI surgeries performed. Prior to 2007, children 3 to 10 years of age made up 50% of the children undergoing BCI, whereas those <3 years made up only 33%. In 2007 this shifted more toward the younger age group (47% for those <3 years and 40% for 3-10-year-olds; P < .001). United States clinics had a higher proportion of adult BCI patients (59% children, 41% adults) than the non-United States clinics (78% children, 22% adults; P < .001). The majority of responders do not hold to a minimum or maximum age by which they limit BCI. Worldwide experience with BCI is now quite extensive and provides a useful base for evaluating clinical outcomes across patient categories and for providing further support during the patient/parent counseling process.

This study was designed to investigate the perceptual benefits and potential risks of implanting the Nucleus(R) multichannel auditory brainstem implant. Between September 1992 and October 1997 a total of 27 subjects received a Nucleus 20- or 21-channel Auditory Brainstem Implant (ABI). All subjects involved in the trial had bilateral acoustic tumour as a result of neurofibromatosis type 2 (NF2) resulting in complete dysfunction of the VIIIth nerve. The study used each subject as their own control without a preoperative baseline because residual hearing, if existing, was destroyed at surgery by tumour removal. A battery of speech tests was conducted to evaluate each patient's performance and communication abilities. Tests were conducted, where possible, in the auditory-only, visual-only, and auditory-visual conditions at 3 days postoperatively (baseline), at 3-mo intervals for the first year and every 12 mo thereafter. A subjective performance questionnaire was administered together with an extensive neurological examination at each test interval. 27 subjects involved in this trial were successfully implanted with a Nucleus ABI. One subject died 2 days postoperatively due to a lung embolism unrelated to the device. Twenty-six subjects underwent device activation and all but one patient received auditory sensation at initial stimulation (96.2%). On average 8.6 (+/-4.2) of the available 21 electrodes were used in the patients' MAPs. Performance evaluation measures showed that the majority of users had access to auditory information such as environmental sound awareness together with stress and rhythm cues in speech that assist with lipreading. Although most subjects did not achieve any functional auditory-alone, open-set speech understanding, two subjects from this series (7.4%) did receive sufficient benefit to be able to use the ABI in conversation without lipreading. Although the medical risks and surgical complexity associated with ABI device implantation are far greater than those for a cochlear implant, the clinical results from this trial show that the Nucleus multichannel ABI is capable of providing a significant patient benefit over risk ratio for subjects suffering loss of hearing due to bilateral retrocochlear lesions.