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The rehabilitation of completely or profoundly deaf patients with a cochlear implant shows different results in their ability to communicate. These differences are certainly based upon the different kind and degree of the disease or damage leading to the loss of hearing. But as CI-systems are also different, an attempt was made to find out the CI-system offering the best chance for an optimal communication ability. Anonymously answered questionnaires of 45 and 193 patients in 2 series were statistically analysed. In both the 95% intervals of confidence for numbers of patients with 2 different CIs who could mainly communicate without additional optical or electronic help did not overlap. For Nucleus 62% and for MED-EL 83% of patients obtained a mainly free communication ability. The difference was statistically significant., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: Speech audiometry plays an important role for hearing evaluation in children. Hearing impaired children, such as those with cochlear implant (CI) who frequently undergo testing, learn the test words by heart. Furthermore, the standard tests use words of former time., Patients and Methods: Using the most frequently words of modern children's literature a speech assessment test was developed for children between 1 to 8 years. The material was first evaluated on normal hearing children. In a second step the phoneme and word perception scores of 35 CI children were measured using 60 - 100 dB SPL according to the most comfortable level (MCL) in free sound field., Results: The performance-intensity function for the single words were highly comparable with those of the Freiburger or Göttinger speech perception test. The average speech reception threshold in CI children was 44 % (test I), 36 % (test II), 63 % (test III) and 69 % (test IV), respectively. Compared to the Mainzer and Göttinger speech perception test the new words were more difficult to understand than those of the known tests. However, a statistically significant difference could be noted only for test II., Conclusions: The new developed "Würzburger speech perception test" appears to be a useful additional tool for the evaluation of hearing impaired children in addition to the standard test procedures.

This article presents a simple method of analysing speech test scores which are biased through ceiling effects. Eighty postlingually deafened adults implanted with a MED-EL COMBI 40/40+ cochlear implant (CI) were administered a numbers test and a sentence test at initial device activation and at 1, 3, 6, 12 and 24 months thereafter. As a measure for speech recognition performance, the number of patients who scored at the 'ceiling level' (i.e. at least 95% correct answers) was counted at each test interval. Results showed a quick increase in this number soon after device activation as well as a continuous improvement over time (numbers test: 1 month: 51%; 6 months: 73%; 24 months: 88%; sentence test: 1 month: 33%; 6 months: 49%; 24 months: 64%). The new method allows for the detection of speech recognition progress in CI patient samples even at late test intervals, where improvement curves based on averaged scores are usually assuming a flat shape., (Copyright 2004 S. Karger AG, Basel)

The cochlear implantation, especially after bilateral operation provides a reliable and outstanding compensation in bilateral complete deafness or severe hearing impairment. Directional hearing can be restored with bilateral implantation so that warning signals are localized correctly and speech in noise is easier understood. Thus, rehabilitation is restored to a high degree. The involved expenses are severe, but are lower for the society when compared to the amount of money necessary to substitute a completely deaf patient lifelong.

Background: Cochlear implantation has become the method of choice for the treatment of deaf patients. A better technology of stimulation opened a wider field of patients suitable for cochlear implantation. Aim of the present study was to evaluate to which extent senior patients benefit by cochlear implantation., Patients and Methods: 36 patients between 65 and 85 years were tested by the Freiburger speech test for monosyllabic words and by the HSM sentence test with and without noise. The results were compared to those of younger implanted patients (16 - 64 years, n = 101)., Results: The speech perception for monosyllabic words did not differ significantly between both groups. A maximum plateau in speech perception for monosyllabic words was reached after 2 years at 55 %. The HSM sentence test revealed significant differences in the increase of speech perception between senior and younger patients in the first post surgical year. After one year elderly patients reached the same perception score as younger patients with a maximum of approximately 80 % after 3 years. At a signal to noise ratio of 15 % younger patients achieved a maximal perception of 55 % after 1 year whereas senior patients needed 4 years to reach this level., Conclusions: Senior patients benefited by cochlear implantation to the same extent as younger patients did. Senior patients gained a similar speech perception level as younger implanted patients although the elderly needed more time to reach the same scores. Nevertheless, cochlear implantation should not be denied due to age alone.

Auditory performance of cochlear implant (CI) children was assessed with the Listening Progress Profile (LiP) and the Monosyllabic-Trochee-Polysyllabic-Word Test (MTP) following the EARS protocol. Additionally, the 'initial drop' phenomenon, a recently reported decrease of auditory performance occurring immediately after first fitting, was investigated. Patients were 140 prelingually deafened children from various clinics and centers worldwide implanted with a MEDEL COMBI 40/40+. Analysis of LiP data showed a significant increase after 1 month of CI use compared to preoperative scores (p < 0.01). No initial decrease was observed with this test. Analysis of MTP data revealed a significant improvement of word recognition after 6 months (p < 0.01), with a significant temporary decrease after initial fitting (p < 0.01). With both tests, children's auditory skills improved up to 2 years. Amount of improvement was negatively correlated with age at implantation., (Copyright 2003 S. Karger AG, Basel)

Objective: The purpose of the study was to investigate speech reception in noise in subjects who had undergone bilateral implantation with multichannel cochlear implants., Methods: Nine adults with bilateral MED-EL implants were included in the study. The subjects were tested using both implants and the better implant only. Tests were performed in a symmetrical setup, which ideally eliminates any head shadow effect. Speech tests included sentences in quiet and at various signal-to-noise ratios. From the results, the gain in signal-to-noise ratios at the speech reception threshold was determined., Results: All subjects showed a substantial gain in signal-to-noise ratios of approximately 4 dB on average. In addition, the gain in signal-to-noise ratios was essentially stable for as long as 4.4 years., Conclusions: The results indicate that bilateral cochlear implant users are able to binaurally process speech.

Objective: The purpose of the study was to investigate speech understanding in quiet and noise in subjects bilaterally implanted with multi-channel cochlear implants., Design: Nine adults bilaterally implanted with MED-EL implants were included in the study. The subjects were tested in three conditions: with both implants, with the right implant only, and with the left implant only. Speech tests included monosyllables in quiet and sentences in noise (10 dB signal to noise ratio). Speech was presented from the front, and noise was presented from either 90 degrees or 270 degrees azimuth., Results: All subjects reported benefit from bilateral stimulation. Speech scores for all subjects were higher with bilateral than with unilateral stimulation. The average score across subjects for sentence understanding was 31.1 percentage points higher with both cochlear implants compared with the cochlear implant ipsilateral to the noise, and 10.7 percentage points higher with both cochlear implants compared with the cochlear implant contralateral to the noise. The average score for recognition of monosyllabic words was 18.7 percentage points higher with both cochlear implants than with one cochlear implant. All of these differences in average scores were significant at the 5% level., Conclusions: Bilateral cochlear implantation provides a significant benefit in speech understanding in both quiet and noise.

Background: The goal of this study was to compare the auditory behaviour of bilaterally implanted children while using both CIs to their auditory behaviour during the time when they were using one CI., Methods: For this purpose a questionnaire looking at different aspects of hearing such as hearing in background noise, in complex listening situations and directional hearing was developed. The questionnaire was completed by the parents of 28 bilaterally implanted children. They were instructed to state their judgement on the behaviour of their children. The parents scaled their judgements using a method of extended category scaling similar to that applied in the loudness scaling with the Würzburg hearing field (WHF). Each of the five verbal categories was subdivided into 10 numerical subdivisions, so that the parents were able to express judgements lying between the different categories., Results: Eight out of eleven items showed that hearing with bilateral CIs was significantly better than with one CI (p < 0,003). The two items, which did not show a significant difference between the two conditions were those related to the interest in auditory rehabilitation and to aversion to noise., Conclusions: The questionnaire has proven to be a useful instrument to assess the quality of hearing in children. The possibility of bilateral implantation should be considered during the decision process prior to implantation.

Background: Although being established as a standard procedure in intra-operative monitoring in acoustic neurinoma surgery, auditory brainstem responses (ABR) represent a far-field technique bearing some technical limitations. This prospective study was designed to evaluate electrocochleography (ECochG) as a supplementary tool for hearing preservation., Method: 84 patients with unilateral intra-/extrameatal acoustic neurinomas (extrameatal diameter: 5-55 mm) preserving serviceable hearing, were operated on using a combined (neuro-/otosurgical) suboccipital approach. ECochG was recorded simultaneously to ABR following transtympanic insertion of a steel needle electrode into the promontory under otoscopic view., Findings: Serviceable hearing (Class 1-3 according to Gardner/Robertson) was preserved in 43 out of 84 patients (51.2%), of whom 40 showed both ECochG and ABR being preserved. All 24 patients with loss of both modalities became deaf. Hearing preservation was observed in 4 out of 12 patients with preserved ECochG but loss of ABR (waves III-V). The reverse was observed in 2 cases with postoperative deafness. While both ECochG and ABR amplitudes were significantly correlated with pre- and postoperative hearing, latencies of ECochG summating (SP) and action potential (AP) proved to be more reliable indicators for preserved hearing than ABR (peak I/III/V) latencies. The predictive value of baseline ABR amplitudes for postoperative hearing, however, was superior to ECochG parameters. Only in large neurinomas (extrameatal diameter: >2 cm) tumour size was found to be a significant predictor for the preservation of hearing. Apart from three cases with postoperative otoliquorrhea and one further case presenting with local bleeding within the external acoustic meatus, no side effects were observed., Conclusions: In combination with ABR monitoring, ECochG proved to be a useful supplementary tool for hearing preservation in acoustic neurinoma surgery. It is particularly helpful during electrocautery and drilling, since no averaging is required. Special applications are: (1) small tumours with good serviceable hearing; (2) and/or a large intrameatal portion; (3) cases with lost or endangered contralateral hearing (e.g. bilateral acoustic neurinomas), when the preservation of poor or even non-functional hearing is desirable.

A study was conducted to compare the new MED-EL TEMPO+ ear-level speech processor with the CIS PRO+ body-worn processor in the COMBI 40/COMBI 40+ implant system. Speech tests were performed in 46 experienced subjects in two test sessions approximately 4 weeks apart. Subjects were switched over from the CIS PRO+ to the TEMPO+ in the first session and used only the TEMPO+ in the time between the two sessions. Speech tests included monosyllabic word tests and sentence tests via the telephone. An adaptive noise method was used to adjust each subject's scores to approximately 50%. Additionally, subjects had to complete a questionnaire based on their 4 weeks of experience with the TEMPO+. The speech test results showed a statistically significant improvement in the monosyllabic word scores with the TEMPO+. In addition, in the second session, subjects showed a significant improvement when using the telephone with the TEMPO+, indicating some learning in this task. In the questionnaire, the vast majority of subjects found that the TEMPO+ allows equal or better speech understanding and rated the sound quality of the TEMPO+ higher. All these objective and subjective results indicate the superiority of the TEMPO+ and are mainly attributed to a new coding strategy called CIS+ and its implementation in the TEMPO+. In other words, based on the results of this study, it appears that after switching over from the CIS PRO+ to the TEMPO+, subjects are able to maintain or even improve their own speech understanding capability., (Copyright 2001 S. Karger AG, Basel)

Background: Unidentified and untreated early infant hearing loss leads to speech-language deficits as well as to cognitive, intellectual, emotional and psychosocial handicaps. Targeted hearing screening programs may miss approximately 50% of all hearing impaired children., Methods: In an universal hearing screening program with a two stage protocol, 1349 newborns were examined using the CRESCENDO Newborn Hearing Screener according to Finkenzeller and a clinical ABR system operating with a time course step stimulus algorithm., Results: Five newborns that failed the two stage screening protocol were diagnosed as hearing impaired so that therapy was initiated before the age of six months. The specificity of the method was 98.8%. The CRESCENDO method only required a short examination time and was easy to apply., Conclusions: Hearing screening programs using ABR offer advantages when compared to evoked otoacoustic emission testing. ABR threshold detection with the time course step stimulus algorithm is a quick and easy to apply method with high specificity that can be recommended for newborn hearing screening.

Background: The cochlear implant is the therapy of choice for completely deaf patients. With this concept speech communication can be restored or developed., Methods: The selection of the implant system may depend on different factors. As long as speech competence is thought to be of highest importance, a fast stimulation strategy involving a state of the art cochlear implant that provides 1500 Hz for every single electrode is close to the optimum. Further parameters include deep insertion into the cochlea (normally 30 mm) and other technical details., Results: With these conditions fulfilled, about 2/3 of the adult deaf patients will later be able to use a telephone. Children who received implants in due time and do not have other cerebral defects will be partly able to meet with the requirements of normal schools.

Objective: To investigate the interrelation between number of channels and stimulation rate in the continuous interleaved sampling strategy (CIS)., Subjects and Methods: Three of the first recipients of the new COMBI 40+ cochlear implant participated in consonant, vowel, number, and sentence tests. Speech understanding was evaluated for different combinations of number of active channels from two to twelve and stimulation rate per channel between 1,515 and 9,090 pulses per second., Results: The results indicate that the optimum number of active channels is not necessarily the maximum number of usable channels.

This study compares sentence understanding in quiet and in noise with 3 different speech coding strategies for cochlear implants. The results show that the spectral-peak (SPEAK) and continuous-interleaved-sampling (CIS) coding strategies, based on spectral signal analysis, allow for better speech understanding in quiet as well as in noise, than the multipeak (MPEAK) coding strategy, which relys on speech feature extraction. In the intrasubject comparison of the MPEAK and SPEAK strategies, the SPEAK coding strategy provided a considerable improvement in quiet and in noise for the majority of patients using the Nucleus 22 Mini-implant. In the intersubject comparisons, the mean results in noise with the CIS strategy were superior to both the MPEAK and the SPEAK strategies. The difference was greatest for the most difficult tests in noise. Understanding in noise was least reduced for the CIS strategy. Understanding in quiet was not significantly different between the CIS and the SPEAK strategies; both strategies were significantly better than the MPEAK strategy in quiet. These results are still preliminary, due to the relatively small number of patients and the great inherent intersubject variability of results.

Ionomer-based cement is a new bone replacement material. After promising results have been obtained with this material in middle ear and skull base surgery as well as in plastic reconstructive surgery, this material can be used to fix a cochlear implant system (internal receiver as well as the electrode) to the temporal bone. This material is formed via a reaction of a glass powder with a polycarboxylic acid. The cement has a manipulation period of about 5 minutes. After setting, the cement is well tolerated by tissue and has the additional advantage of being biocompatible and permanently stable in a biological environment. The cement and the acid are commercially available as a two-component capsulated system. In cochlear implant surgery this material is used to achieve a stable attachment of the internal receiver to the temporal bone. Displacement and damaging of the internal receiver and the electrode are prevented.

The amplitudes of the stapes footplate movements were determined in human temporal bones when the ossicular chain was drilled with a cutting and a diamond burr. High movements result in comparison to physiological data. The frequency distribution resembles the dB (A) curve. The intensity compared to sound pressure levels on the ear drum is higher than I30 dB. The pressure is constant over the period of contact between the burr and the ossicle. Most likely these unphysiologic movements of the stapes footplate can cause inner ear damage as we had to admit in a case of facial nerve decompression.