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ABSTRACT: OBJECTIVE: Identify likely predictors for the outcome after contralateral cochlear implantation with a long interimplant delay. STUDY DESIGN: Retrospective case reviews. SETTING: Outpatient cochlear implant (CI) center. PATIENTS: Seventy-three children and adolescents who underwent sequential bilateral cochlear implantation with an interval between both implantations of 5 years or longer. The mean age of the patients at the first and second cochlear implantations was 2.72 ± 1.52 and 11.57 ± 2.9 years, respectively. The mean duration of experience with both implants was 4.01 ± 1.57 years. INTERVENTION: Rehabilitative. MAIN OUTCOME MEASURES: All 73 patients underwent periodic speech perception testing in quiet and noise. The most recent unilateral data for each side were statistically analyzed. The speech test results were evaluated by the age at first implantation, the interval between both implantations, the duration of hearing aid use in the second side, and the duration of the bilateral CI use. RESULTS: A statistically significant difference for speech test results was obtained between the early-implanted ears and the late-implanted ears for all children. These results were dependent on the interimplant interval. All age groups demonstrated significant differences (p > 0.05) for the second side between the speech test results and the interval between both cochlear implantations. In addition, statistically significant differences influenced by the duration of hearing aid use were found for speech test results for the second side. Experience was also a factor for the second CI, yielding significantly higher speech test scores with longer use. CONCLUSION: The development of hearing abilities in a second-implanted side depends on the interimplant interval, the hearing aid use, and the duration of the second CI use.
Otology & neurotology: official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology 05/2013; · 1.44 Impact Factor
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ABSTRACT: The objective of this study was to examine the anatomical, audiological, and surgical factors that can affect the hearing outcome in Pendred syndrome cochlear implant recipients. Patients with Pendred syndrome represent challenging cochlear implant candidates, combining goiter, severe-to-profound hearing loss, and inner-ear dysplasias. The hearing outcome and further relevant parameters in such patients have not been adequately evaluated yet.
Retrospective study in a tertiary referral cochlear implant centre. Data of patients with Pendred syndrome, who had undergone cochlear implantation in the 10-year period 1999-2008, were evaluated.
Five cochlear implant recipients with Pendred syndrome were identified, four unilateral and one bilateral. The average postoperative follow-up duration for these patients was 4.8 years. Enlarged vestibular aqueduct and Mondini dysplasia were the most common anatomical findings. Although these anatomical variances did not affect the electrode insertion, they prolonged the duration of the surgery. Cerebrospinal fluid gusher was the most common intraoperative complication. All patients enjoyed satisfactory hearing rehabilitation.
Cochlear implantation is the proper method for optimal hearing rehabilitation in patients with Pendred syndrome. Although the precise pathogenetic mechanism and the genetic background of deafness in Pendred syndrome have not been completely understood, the preexisting hearing experience represents a positive factor for satisfying hearing outcome. The inner-ear malformations can cause mild surgical difficulties and extended surgery duration. The cochlear implant surgeon should be aware of these difficulties to avoid complications.
Cochlear implants international 08/2011; 12(3):157-63.
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Cochlear implants international 05/2011; 12 Suppl 1:S109-13.
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ABSTRACT: The objective of this study was a state-of-the-art analysis of cochlear implantation in patients with Waardenburg syndrome (WS).
Twenty-five patients with WS treated with cochlear implants in our department from 1990 to 2010.
The 25 patients with WS underwent 35 cochlear implantations.
Hearing outcome was evaluated using HSM sentence test in 65 dB in quiet, Freiburg Monosyllabic Test, and categories of auditory performance for children and compared with that of a control group. Anatomic abnormalities of the inner ear were examined using magnetic resonance imaging and computed tomography of the temporal bones.
The mean follow-up time was 8.3 years (range, 0.3-18.3 yr). The majority achieved favorable postimplantation performance with mean HSM scores of 75.3% (range, 22.6%-99%) and Freiburg Monosyllabic Test scores of 67.8% (range, 14%-95%). However, in 4 cases, the results were less satisfactory. The comparison with the control group did not reveal any statistical significance (p = 0.56). In 6 patients (24%), behavioral disorders caused temporary difficulties during the rehabilitation procedure. Except of isolated large vestibule in 1 patient, the radiological assessment of the 50 temporal bones did not reveal any temporal bone abnormalities.
Most patients with WS performed well with cochlear implants. However, WS is related to behavioral disorders that may cause temporary rehabilitation difficulties. Finally, temporal bone malformations that could affect cochlear implantation are notcharacteristic of WS.
Otology & neurotology: official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology 04/2011; 32(6):951-5. · 1.44 Impact Factor
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ABSTRACT: In subjects who are deaf and who also have tinnitus in the affected ear, tinnitus treatments based on acoustic input are impossible. On the other hand, tinnitus suppression using electric stimulation has been reported to be successful. Therefore, a study was initiated to investigate the potential of cochlear implantation (CI) in unilateral deaf subjects regarding tinnitus suppression, device acceptance, and restoration of spatial hearing.
Five subjects with severe to profound unilateral deafness having also ipsilateral tinnitus were enrolled. In monthly visits, the speech processor program was optimized, and the hearing performance as well as tinnitus were monitored. In addition, it was investigated whether the CI improves hearing in adverse listening situations when combined with the normal hearing side.
In 3 participants, the tinnitus was significantly suppressed while wearing the device. In the other 2 participants, the tinnitus could be reduced in certain situations. Speech perception tests revealed a significant benefit with the CI in combination with the normal-hearing side for 3 participants. All participants accepted the device in a clinical setting; adaptation of the frequency allocation was not required.
Improvements were found regarding the hearing and the tinnitus. Not all participants benefit from the CI to the same degree and in the same situations.The results indicate that cochlear implantation in subjects with unilateral severe to profound hearing loss and ipsilateral tinnitus may be beneficial on a case-to-case basis. Further work needs to be performed to define the appropriate indication criteria.
Otology & neurotology: official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology 12/2010; 31(9):1381-5. · 1.44 Impact Factor
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ABSTRACT: Retrospective clinical study.
Academic tertiary referral center at the Medical University of Hannover.
Computed tomographic findings of 126 patients (95 children and 31 adults) profoundly deafened by meningitis during a period of 20 years were evaluated. Children were defined as up to 12 years old at the onset of meningitis. No patients showed any relevant bilateral auditory brainstem response thresholds at the time of admission to our clinic.
Patient histories, surgical findings, and imaging results were analyzed by experienced surgeons/neuroradiologists.
Of 95 children, 30 (32%) displayed symptoms of labyrinthitis ossificans, whereas 11 (36%) of 31 adults showed changes of the bony structure of the cochlea. High-resolution computed tomography (HRCT) evaluation indicated that the ossification was detected more frequently if there was a larger time interval between onset of meningitis and high-resolution computed tomographic scan. Bilateral ossification at various stages was observed in 67% of children and 55% of adults with obliteration. In the comparison of cochlear ossification found in computed tomographic scans and intraoperative obliteration, HRCT showed a specificity of 73% and a sensitivity of 88%. The intraoperative evaluation revealed various stages of cochlear obliteration in 44% of children and 39% of adults.
In our study, the earliest onset of labyrinthitis ossificans was found in high-resolution computed tomographic scans as early as 4 weeks after the onset of meningitis. In most cases, ossification occurred bilaterally with predominantly asymmetric involvement of both ears. The rate of osteoneogenesis increases significantly over time after meningitis. This leads to the conclusion that cochlear ossification can start very early and increase over time with unpredictable speed. Cochlear ossification typically develops bilaterally. From these results, we conclude that cochlear implantation should be performed bilaterally as soon as possible after meningitis and deafness have been diagnosed. HRCT offers good specificity but only limited sensitivity. Preoperative diagnostics should include magnetic resonance imaging to optimize preparation for cochlear implantation.
Otology & neurotology: official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology 09/2010; 31(7):1072-8. · 1.44 Impact Factor
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ABSTRACT: The evaluation of long-term results of cochlear implantation in patients with typical Cogan syndrome.
The medical records of approximately 3,000 patients who underwent cochlear implantation in a tertiary centre within the period 1992-2007 were retrospectively examined.
Four cochlear implant recipients with Cogan syndrome (6 implantations) were identified. One cochlea was found to be partially obliterated; the electrode could, however, be completely inserted. Wound healing disorders and infections in a patient with systemic symptoms were the only postoperative complications. Hearing outcome was favorable, with average HSM and monosyllabic scores of 96.7 and 82.5%, respectively, in an average follow-up time of 9.25 years.
Cochlear implantation is the appropriate hearing rehabilitation method in Cogan syndrome patients. Although the basic illness does not affect the long-term hearing outcome, skin-atrophy-related complications in cases with systemic symptoms may occur. Finally, the cochlear implant surgeon should be aware of the possible cochlea obliteration.
ORL 01/2010; 72(5):275-9. · 0.91 Impact Factor
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ABSTRACT: The objective of this paper is to evaluate the advantages of the Advanced Bionic high resolution mode for speech perception, through a retrospective analysis. Forty-five adult subjects were selected who had a minimum experience of three months’ standard mode (mean of 10 months) before switching to high resolution mode. Speech perception was tested in standard mode immediately before fitting with high resolution mode, and again after a maximum of six months high resolution mode usage (mean of two months). A significant improvement was found, between 11 and 17%, depending on the test material. The standard mode preference does not give any indication about the improvement when switching to high resolution. Users who are converted within any study achieve a higher performance improvement than those converted in the clinical routine. This analysis proves the significant benefits of high resolution mode for users, and also indicates the need for guidelines for individual optimization of parameter settings in a high resolution mode program. Sumario El objetivo de este trabajo fue el de evaluar las ventajas del modo de alta resolución del Advanced Bionics en la percepción del lenguaje, a través de un análisis retrospectivo. Se seleccionaron 45 adultos con una experiencia mínima en el uso del modo estándar por tres meses (media de 10 meses) antes de activar el modo de alta resolución. Se evaluó la percepción del lenguaje en el modo estándar inmediatamente antes del uso del modo de alta resolución y de nuevo, después de un máximo de seis meses de experiencia con éste último modo (media de 2 meses). Se encontró una mejoría significativa entre el 11 y el 17%, dependiendo del material de prueba. La preferencia por el modo estándar no dio ninguna indicación acerca de la mejoría al cambiar al modo de alta resolución. Los usuarios que cambiaron sin ningún estudio, lograron un rendimiento más alto que aquellos que cambiaron en la rutina clínica. Este análisis prueba el beneficio significativo para los usuarios del modo de alta resolución e indica también la necesidad de guías para la optimización individual en el control de los parámetros del programa de modo de alta resolución.
07/2009; 45(7):407-416.
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ABSTRACT: The objective of this study was to investigate the long-term effect of intraoperative application of steroid suspension and coating of the electrode contacts with a thin film of iridium oxide on the intracochlear impedance development after cochlear implantation and on the impedance difference before and after stimulation.
Time-dependent development of intracochlear impedances was investigated in 4 different groups of adult patients up to 4 years after implantation. Additionally, during rehabilitation period just after first fitting, impedances before and after stimulation were measured as to investigate the influence of electrical stimulation on the impedances. Results from standard Nucleus 24 Contour (control), standard Nucleus 24 Contour with intraoperative application of steroids, iridium-coated Nucleus 24 Contour, and iridium-coated Nucleus 24 Contour with intraoperative application of steroids were compared.
Steroid application reduced impedances significantly throughout the observation period of up to 4 years after implantation. Iridium oxide coating had no effect. Differences between the groups were mainly found on the basal and middle parts of the cochlea, but not close to the tip of the array, also indicating that postoperative fibrous tissue growth is stronger in the basal region of the cochlea. Group mean values of the stimulation effect were not influenced by the different treatments. Nevertheless, only in both steroid-treated groups a correlation between the impedance before stimulation and the stimulation effect was found.
Although the differences between control and steroid-treated groups decrease with time, single intraoperative intracochlear steroid deposition was proven to lower postoperative impedances during first 3 to 4 years after implantation probably because of reduction of fibrous tissue growth.
Otology & neurotology: official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology 07/2009; 30(5):592-8. · 1.44 Impact Factor
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ABSTRACT: Patients with high-frequency deafness and/or substantial residual hearing across frequencies might benefit from combined electro-acoustic stimulation. The Hybrid-L electrode was designed to address the issues of both hearing conservation and effective electrical stimulation in those recipients. The electrode with 22 contacts should be inserted through the round window membrane, and covers approximately 270 degrees of the basal turn of the cochlear. This insertion length is equivalent to the one seen in many patients using the former Nucleus straight electrode. Twenty-four patients with low-frequency thresholds of 60 dB or better, up to 500 Hz, were implanted with a Hybrid-L device in a clinical trial at the Medical University of Hannover. Another group of 8 recipients with less residual hearing was included under extended inclusion criteria. Residual hearing was conserved in the majority of cases. One patient had a loss of more than 30 dB, but hearing partially recovered after 9 months. The median loss in all patients was 10 dB in both the Hybrid group and the extended group. Patients were able to use the residual hearing postoperatively to the same extent as preoperatively. In the Hybrid mode (cochlear implant + ipsilateral hearing aid), patients showed a significant improvement of 21% (p = 0.002) in speech understanding in quiet using the Freiburger Monosyllabic Word Test compared to the preoperative scores under aided conditions with their hearing aid. The Oldenburg Sentence Test in noise showed a remarkable average improvement of 10.2 dB (p < 0.001) compared to the preoperative hearing aid only mode. An additional improvement could be seen in the combined mode using an additional contralateral hearing aid. Recipients with a shorter duration of high-frequency hearing loss showed a larger benefit than those with a longer duration of hearing loss. Hearing conservation using the Hybrid-L electrode and a given surgical technique is possible with high probability in patients with high-frequency deafness or pantonal hearing loss. The use of the residual acoustic hearing offers specific advantages, especially for understanding speech in noise and for spatial hearing.
Audiology and Neurotology 01/2009; 14 Suppl 1:22-31. · 2.46 Impact Factor
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ABSTRACT: Morbus Usher (USH), a combination of sensorineural hearing loss and retinal visual impairment, is classified into group I-III. USH I patients are born deaf. Within the first 10 years of life, they develop a severe vision impairment due to progressive retinal dystrophy (retinitis pigmentosa). USH I patients show vestibular deficits. The incidence of USH I among congenitally deaf children is assumed to be as high as 10%. We intend to create a simple examination procedure for screening congenitally deaf children for vestibular deficiency and subsequently USH I. The examination procedure is named "Minimized Rotation". The vestibular function of deaf children was examined by Minimized Rotation during their preoperative cochlear implant candidacy examination. A lack of postrotational nystagmus was seen as an indication for vestibular deficit. Subsequently some of these patients were examined under general anaesthesia by electroretinography (ERG) at the Department of Ophthalmology. A total of 117 children were examined by Minimized Rotation. In 19 children (16.2%) no rotational nystagmus was found. Six of these children were additionally examined at the Department of Ophthalmology using Ganzfeld ERG. Three of them (50%) showed generalized dysfunction of the retina; 8.1% of the children undergoing preoperative evaluation for cochlear implatation are assumed to show abnormalities of the retina. Rotational examination seems to be an appropriate screening method to detect vestibular deficits, which is one sign of USH I. The results always have to be verified by Ganzfeld-ERG or further genetic investigations. Children with USH I are threatened by progressive reduction of vision. We, therefore, consider USH I children always to be implanted bilaterally with a cochlear implant to maximize the benefit of auditory rehabilitation.
Archiv für Klinische und Experimentelle Ohren- Nasen- und Kehlkopfheilkunde 08/2008; 265(7):759-63. · 1.29 Impact Factor
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ABSTRACT: Sequential bilateral implantation offers listening advantages demonstrable on speech recognition in noise and for lateralization. Whilst the trend was for shorter inter-implant intervals and longer implant experience to positively impact binaural advantage, we observed no contraindications for binaural advantage.
To evaluate the benefits of sequential bilateral cochlear implantation over unilateral implantation in a multicentre study evaluating speech recognition in noise and lateralization of sound.
Twenty children, implanted bilaterally in sequential procedures, had the following characteristics: they were native German-speaking, were3 years or older and had a minimum of 1 year inter-implant interval and had between 2 months and 4 years 7 months binaural listening experience. Binaural advantage was assessed including speech recognition in noise using the Regensburg modification of the Oldenburger Kinder-Reimtest (OLKI) and lateralization of broadband stimuli from three speakers.
A significant binaural advantage of 37% was observed for speech recognition in noise. Binaural lateralization ability was statistically superior for the first and second implanted ear (p = 0.009, p = 0.001, respectively). Binaural experience was shown to correlate moderately with absolute binaural speech recognition scores, with binaural advantage for speech recognition and with binaural lateralization ability. The time interval between implants correlated in an inverse direction with binaural advantage for speech recognition.
Acta Oto-Laryngologica 09/2007; 128(2):164-76. · 1.08 Impact Factor
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ABSTRACT: Perimodiolar intracochlear electrodes with contacts facing towards the modiolus have limited current flow towards the outer wall of the cochlea and therefore, may reduce the occurrence of facial nerve stimulation (FN) in cochlear implant subjects.
Facial nerve stimulation is a well-known complication in cochlear implant treatment especially in the group of subjects with otosclerosis. The possible explanation of this side effect is a change of the electrical properties of the otosclerotic bone leading to leakage current and resulting in facial nerve stimulation.
Four CI subjects who had been implanted with a Nucleus Mini22 device with a Nucleus Straight electrode between 9 to 12 years ago suffered from severe FN stimulation. Electrode contacts had to be switched off so that they could only use 4, 11, 13, and 15 electrodes of their usual set of 22. The switch off resulted in deteriorating speech understanding over time. Therefore, all subjects were reimplanted with a Nucleus 24R device with a Contour electrode. Preoperatively, the threshold of FN stimulation was obtained on all electrodes subjectively. Intraoperatively, FN stimulation thresholds were measured objectively with both, the old and the new device and were compared. NRT and SRT thresholds were also obtained with the reimplanted device to assure effective electrical stimulation of the auditory nerve.
In all four cases the postoperative fitting demonstrated no FN stimulation on all electrodes up to maximum comfortable level. The insertion of the Contour electrode array was complete in three cases, in one case the array could only be inserted partially similarly to the situation before the reimplantation. Speech perception tests showed a significant improvement in all subjects with the new device.
Electrodes with modiolar facing contacts and perimodiolar position like the Nucleus Contour electrode reduce the possibility of facial nerve stimulation significantly due to more focused electrical stimulation.
Ontology & Neurotology 11/2006; 27(7):918-22. · 1.90 Impact Factor
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ABSTRACT: The objective of this study was to investigate the effect of intraoperative application of steroid suspension and coating of the electrode contacts with a thin film of iridium oxide on the short-term, time-dependent development of the intracochlear impedance in adults implanted with the Nucleus 24 Contour electrode.
The time-dependent development of intracochlear impedances was investigated in four different groups of adult patients at daily and later weekly intervals until the first fitting. The four groups were as follows: 1) standard Nucleus 24 Contour (control, n = 7); 2) standard Nucleus 24 Contour with intraoperative application of steroids (Group S, n = 6); 3) iridium-coated Nucleus 24 Contour control (Group I, n = 8); and 4) iridium-coated Nucleus 24 Contour with intraoperative application of steroids (Group I + S, n = 5). All patients had postlinguistic onset of severe to profound sensorineural hearing loss and no or little benefit of conventional hearing aids. Absence of ossification or any other cochlear anomaly and also absence of signs of retrocochlear or central origin to the hearing impairment bilaterally had to be confirmed preoperatively.
Steroid application reduced impedances significantly (Groups S and I + S), whereas iridium coating lowered variance of the impedance among patients but did not reduce the impedance significantly. The steroid-induced reduction is more pronounced at basal electrode contacts. Furthermore, there is some indication that the tissue growth could be faster in patients having the iridium-coated Contour electrode.
Provided that the reduction of electrode impedances with application of steroids is persisting, intracochlear application of steroids can be considered on a regular basis. Iridium coating of the electrode contacts seems not to be justified to be included as standard procedure.
Ontology & Neurotology 09/2006; 27(5):639-47. · 1.90 Impact Factor
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ABSTRACT: The objective of this paper is to evaluate the advantages of the Advanced Bionic high resolution mode for speech perception, through a retrospective analysis. Forty-five adult subjects were selected who had a minimum experience of three months' standard mode (mean of 10 months) before switching to high resolution mode. Speech perception was tested in standard mode immediately before fitting with high resolution mode, and again after a maximum of six months high resolution mode usage (mean of two months). A significant improvement was found, between 11 and 17%, depending on the test material. The standard mode preference does not give any indication about the improvement when switching to high resolution. Users who are converted within any study achieve a higher performance improvement than those converted in the clinical routine. This analysis proves the significant benefits of high resolution mode for users, and also indicates the need for guidelines for individual optimization of parameter settings in a high resolution mode program.
International Journal of Audiology 08/2006; 45(7):407-16. · 1.40 Impact Factor
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Anke Lesinski-Schiedat
Laryngo-Rhino-Otologie 11/2002; 81(10):741-2. · 0.97 Impact Factor
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ABSTRACT: To explore, from the payers' perspective, the cost-benefit ratio of pediatric cochlear implantation for congenitally deaf and prelingually deafened children compared with children with hearing aids. The study should verify the hypothesis that educational and associated costs increase with age at implantation and that these can be below costs for children with hearing aids.
Children who received implants at the Medical University of Hanover at different ages (Group 1, 0-1.9 yr; Group 2, 2-3.9 yr; Group 3, 4-6.9 yr) were compared with deaf children using hearing aids (Group 4). Sick funds were the payers for direct and indirect costs, and public authorities were the payers for educational costs. Educational settings were used to measure for benefits. All costs related to the hearing deficiency were included up to the age of 16 years on the basis of 1999 currency values. A scenario analysis was used to explore the impact of variation of costs and discount rates.
Total costs for the three age groups of children with implants were from euro 138,000 (approximately US$113,100) to euro 177,000 (approximately US$152,700), compared with euro 160,000 (approximately US$138,000) for hearing aid users.
This study supports the view that pediatric cochlear implantation provides positive cost-benefit ratios compared with hearing aid users, depending on the age at implantation. Implantation is strongly recommended from the payers' perspective for children implanted before the age of 2 years.
Ontology & Neurotology 10/2002; 23(5):674-81. · 1.90 Impact Factor
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ABSTRACT: OBJECTIVE The purpose of this study was to present the patients' recommendations and judgments about their hearing and communication abilities with the help of the auditory brainstem implant.
Prospective study.
Tertiary referral center.
This evaluation was based on the data obtained by the self-administered questionnaires designed for the European Auditory Brainstem Implant Multicenter Clinical Trial. Eleven patients who had used their auditory brainstem implant for a minimum of 6 months to a maximum of 41 months were evaluated with the help of these questionnaires.
All the patients had used their implant on a regular daily basis for an average of 13 hours per day. None of them experienced any side effects during the daily use of the device. Nine patients (82%) used their auditory brainstem implant in both quiet and noisy surroundings. The most common cause of disturbance was a noisy surrounding. All the patients were able to distinguish speech from environmental sounds. The role of the auditory brainstem implant in differentiating various environmental sounds was considered to be very useful by 9 patients (82%). As an adjuvant to lip-reading, the auditory brainstem implant was considered most useful for understanding speech in quiet surroundings.
It was concluded that the auditory brainstem implant is an effective support for receiving and, to some degree, differentiating environmental sounds, and that as an adjuvant to lip-reading, it enhances speech perception, especially in quiet surroundings. A comparison between the results of this study and the results of the audiologic tests presented in Part I of this study (published earlier) revealed that patient satisfaction was not directly correlated with the results of the objective auditory tests. In general, patients' judgments of their individual hearing and communication abilities usually rated higher than could have been predicted by the objective audiometric data.
Ontology & Neurotology 10/2002; 23(5):694-7. · 1.90 Impact Factor
