One hundred and forty-seven adult recipients of the Nucleus 24 cochlear implant system, from 13 different European countries, were tested using neural response telemetry to measure the electrically evoked compound action potential (ECAP), according to a standardised postoperative measurement procedure. Recordings were obtained in 96% of these subjects with this standardised procedure. The group results are presented in terms of peak amplitude and latency, slope of the amplitude growth function and ECAP threshold. The effects of aetiological factors and the duration of deafness on the ECAP were also studied. While large intersubject variability and intrasubject variability (across electrodes) were found, results fell within a consistent pattern and a normative range of peak amplitudes and latencies was established. The aetiological factors had little effect on the ECAP characteristics. However, age affected ECAP amplitude and slope of the amplitude growth function significantly; i.e., the amplitude is higher in the lowest age category (15-30 years). Principal component analysis of the ECAP thresholds shows that the thresholds across 5 electrodes can be described by two factors accounting for 92% of the total variance. The two factors represent the overall level of the threshold profiles ('shift') and their slopes across the electrode array ('tilt'). Correlation between these two factors and the same factors describing the T-and C-levels appeared to be moderate, in the range of 0.5-0.6. AbstractOne hundred and forty-seven adult recipients of the Nucleus ® 24 cochlear implant system, from 13 different European countries, were tested using neural response telemetry to measure the electrically evoked compound action potential (ECAP), according to a standardised postoperative measurement procedure. Recordings were obtained in 96% of these subjects with this standardised procedure. The group results are presented in terms of peak amplitude and latency, slope of the amplitude growth function and ECAP threshold. The effects of aetiological factors and the duration of deafness on the ECAP were also studied. While large intersubject variability and intrasubject variability (across electrodes) were found, results fell within a consistent pattern and a normative range of peak amplitudes and latencies was established. The aetiological factors had little effect on the ECAP characteristics. However, age affected ECAP amplitude and slope of the amplitude growth function significantly; i.e., the amplitude is higher in the lowest age category (15-30 years). Principal component analysis of the ECAP thresholds shows that the thresholds across 5 electrodes can be described by two factors accounting for 92% of the total variance. The two factors represent the overall level of the threshold profiles ('shift') and their slopes across the electrode array ('tilt'). Correlation between these two factors and the same factors describing the T-and C-levels appeared to be moderate, in the range of 0.5-0.6.

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The results suggest that hardware developments achieved in the design of CP810 allow an immediate and relevant directional advantage as compared to the previous-generation Freedom device.

The results indicate that any reduction in sound processor microphone sensitivity causes a degree of hearing decline that negatively affects the cochlear recipient's clinical performance. Microphone faults are often unreported events, and their occurrence rate is underestimated. To establish that the microphone is providing correct input to the speech processor a standard control procedure, including technical and clinical checks, is needed in clinical practice.

IntroductionCochlear implantation (CI) has been available for over 25 years in many countries worldwide. From very early on, it was quite clear that successful implantation was only possible when three major requirements were satisfied: qualified pre-operative patient selection, sophisticated CI surgery, and extensive post-operative rehabilitation.The whole process, assessment for the implantation, the surgery, and the post-operative rehabilitation, involves considerable time and energy as well as great expense to both the patient and the implant team. The decision to embark upon implantation in any individual case should be made jointly by the team and the patient after thoughtful consideration of the likely outcome. The patient should make his or her decision in the light of as much information as the team can provide. In order to ensure optimum benefit from the device, the suitability of the implant for a particular individual must be determined. Expectations about the implant procedure, its potential outcomes, and the considerable post-implant rehabilitation required must be clear and realistic. The implant team needs to provide a service that meets the needs of its patients (Mawman et al., 1996).From the very beginning of CI it was quite clear that the post-operative rehabilitation consists out of two phases: first the acute part soon after surgery to adjust the implantee to his/her new device and to fit the device to his/her individual need, and second the long-term part to ensure the functioning of the device for lifelong use, here referred to as 'aftercare'.As advances in CI technology expand, the need/ demand for CI services continues to grow. Therefore, a major question for every CI program is how can access to CI services be assured for the increasing number of CI recipients without degrading the basic quality of their individual long-term care? MethodsA group of five cochlear implant specialists from five different European countries discussed the issue of aftercare based on their experience and the specific settings of their CI programs. In order to provide a baseline for the discussion, a questionnaire was sent out before the meeting to the five centers to learn more about the experiences and settings in their specific countries; all five responded to the questionnaire. The aim of the meeting was to conclude the results and work out a proposal for future standardization of basic aftercare. ResultsThe findings from this pan-European review concerning different aspects of basic quality standards in CI service demonstrate a fairly wide range of different settings (Table 1). Especially in duration and frequency of aftercare in children, the answers differed greatly. In other areas queried, such as the requirement for minimal staff, the opinions were quite uniform and indicated that a staff of threean ENT physician, a technical audiologist, and a speech therapistwould be sufficient for an aftercare session.The first question that had to be answered in our discussion during the follow-up meeting was how t...