Prevalence of cochlear implants in postlingually deafened adults in a Swedish region

Cochlear implantation (CI) rates vary between countries, depending on identification routines and economic restrictions. The present study aimed at determining the prevalence of CIs in postlingually deafened, aged 20-69 years old, in G?teborg, Sweden. Three patient databases with information on PTA, a questionnaire, medical records and consultations identified 88 subjects with sensorineural hearing loss >/=80 dB HL (PTA of 500, 1000, 3000 Hz), PB word score of 相似文献   

Prevalence of cochlear implants in postlingually deafened adults in a Swedish region

Cochlear implantation (CI) rates vary between countries, depending on identification routines and economic restrictions. The present study aimed at determining the prevalence of CIs in postlingually deafened, aged 20–69 years old, in Göteborg, Sweden. Three patient databases with information on PTA, a questionnaire, medical records and consultations identified 88 subjects with sensorineural hearing loss ≥80 dB HL (PTA of 500, 1000, 3000 Hz), PB word score of ≤30% (better ear), regular use of hearing-aid, and oral language. The prevalence of CIs was 11.8 per 100?000 population, and of subjects fulfilling the audiometric candidacy criteria 18.6 per 100?000. The mean PTA (op. ear) of subjects awaiting operation was 97 dB HL (SD 12.3), and of already implanted subjects 106 dB HL (SD 10.2). Mean PB word score was 9% (SD 8.9) and 3% (SD 4.9) respectively. Subjects awaiting operation had significantly better residual hearing, emphasizing recent changes in candidacy criteria. Comparing with prevalence from other countries demonstrated that more patients could be candidates for cochlear implantation.

Sumario

La tasa de implantes cocleares (CI) varía según los países, dependiendo de las rutinas de identificación y de las restricciones económicas. Este estudio pretende determinar la prevalencia de los CI en adultos ensordecidos de 20 a 69 años en Goteborg, Suecia. Mediante una base de datos con información sobre PTA, un cuestionario, antecedentes médicos y de consulta se identificaron 88 sujetos con hipoacusia sensorineural ≥80 dB HL (PTA de 0.5, 1.0, 3.0 kHz), calificación en palabras PB?≤?30% (mejor oído), uso regular de auxiliares auditivos y de lenguaje oral. La prevalencia de CI fue de 11.8 por 100,000 personas y de 18.6 por 100,000 la de los sujetos que reunían los criterios audiométricos para ser candidatos. El promedio de PTA del oído propuesto en los sujetos que esperaban la operación fue de 97dB HL (SD 12.3) y en los sujetos ya implantados de 106 dB HL (SD 10.2). La calificación promedio de la prueba con palabras PB fue de 9% (SD 8.9) y 3% (SD 4.9) respectivamente. Los sujetos que estaban esperando la cirugía tenían una audición residual significativamente mejor, con énfasis en los recientes cambios en los criterios de candidatura. Comparando la prevalencia de otros países, queda demostrado que más pacientes podrían ser candidatos para implante coclear.     

Evidence-based guidelines for recommending cochlear implantation for postlingually deafened adults

Abstract

Objective: Adult selection criteria for cochlear implantation have been developed based on analysis of the post-operative performance of a large group of postlingually deafened adults. Original criteria published in 2004 were reviewed and amended to reflect outcomes currently being achieved by implant recipients. Design: Retrospective review of 12-month post-operative speech perception performance of adults implanted at the Eye and Ear Hospital, Melbourne, Australia. Study sample: A total of 382 postlingually deafened adults, using a Freedom, Nucleus 5, or CI422 Slim Straight cochlear implant were used to create a comparative set of data. Results: Revised guidelines suggest that adults with postlingual hearing loss can now be considered cochlear implant candidates if they obtain scores of up to 55% for open-set phonemes in quiet in the ear to be implanted. Functional benefit may vary depending on the recipients’ contralateral hearing. Conclusions: This study supports the provision of cochlear implants to candidates with significant residual hearing when at least one ear meets the criterion outlined above. Patient-specific counseling is required to ensure the potential to benefit predicted by the current model is acceptable to the individual patient and their family. Counseling regarding functional benefit must take into consideration hearing in the contralateral ear.     

The relationship between the intraoperative ECAP threshold and postoperative behavioral levels: the difference between postlingually deafened adults and prelingually deafened pediatric cochlear implant users

The purpose of this study was to determine the relationship between electrically evoked compound-action potential (ECAP) thresholds, electrically evoked auditory brain-stem response (EABR) thresholds, behavioral thresholds (T levels) and maximum comfort levels (C levels) in profoundly deaf cochlear-implant users. The ECAP thresholds were measured intraoperatively in eight postlingually deafened adults and nine (eight prelingually and one postlingually deafened) children implanted with the Nucleus CI24 M cochlear implant. The mean ECAP thresholds did not differ between children and adults. The average behavioral T and C levels after at least 6 months of experience with a cochlear implant were significantly higher in children than those in adults. The ECAP thresholds were more strongly correlated with T and C levels in children than in adults. The stronger correlation between ECAP thresholds and behavioral T and C levels in children than in adults might result from differences in loudness sensation, which should in turn depend on auditory experience.     

Residual speech perception and cochlear implant performance in postlingually deafened adults

OBJECTIVE: This study aimed at testing the post-hoc validity of the previously reported predictive index for postoperative cochlear implant performance, based on preoperative duration of deafness, and speech reception. STUDY DESIGN: Adult patients with postlingual severe to profound hearing loss, who were implanted with Cochlear Corporation CI-22 and CI-24 devices were included in this study. We studied the relationship between their postoperative word recognition scores and preoperative factors, namely, duration of deafness, and sentence recognition. We used the same predictive index reported in the previous study to predict their postoperative scores and test the model's agreement with the actual performance. RESULTS: We found that postoperative performance as measured by CNC word scores had an inverse relationship with the duration of deafness, and a direct correlation with the preoperative performance on CID sentence recognition tests. A nonlinear term [Duration / (1+CID)] was shown to improve the correlation coefficient of our predictive index. CONCLUSION: Some predictability of cochlear implant outcome is possible depending on the preoperative duration of deafness and speech recognition abilities. Preoperative residual speech recognition acts as a "trophic factor" that protects the spiral ganglion and/ or the central auditory pathways from degeneration. In other words, it improves the expected postoperative word scores.     

Horizontal-plane localization of noise and speech signals by postlingually deafened adults fitted with bilateral cochlear implants

OBJECTIVES: The main purpose of the study was to assess the ability of adults with bilateral cochlear implants to localize noise and speech signals in the horizontal plane. A second objective was to measure the change in localization performance in these adults between approximately 5 and 15 mo after activation. A third objective was to evaluate the relative roles of interaural level difference (ILD) and interaural temporal difference (ITD) cues in localization by these subjects. DESIGN: Twenty-two adults, all postlingually deafened and all bilaterally fitted with MED-EL COMBI 40+ cochlear implants, were tested in a modified source identification task. Subjects were tested individually in an anechoic chamber, which contained an array of 43 numbered loudspeakers extending from -90 degrees to +90 degrees azimuth. On each trial, a 200-msec signal (either a noise burst or a speech sample) was presented from one of 17 active loudspeakers (span: +/-80 degrees ), and the subject had to identify which source from the 43 loudspeakers in the array produced the signal. Subjects were tested in three conditions: left device only active, right device only active, and both devices active. Twelve of the 22 subjects were retested approximately 10 mo after their first test. In Experiment 2, the spectral content and rise-decay time of the noise stimulus were manipulated. RESULTS: The relationship between source azimuth and response azimuth was characterized in terms of the adjusted constant error (?). (1) With both devices active, ? for the noise stimulus varied from 8.1 degrees to 43.4 degrees (mean: 24.1 degrees ). By comparison, ? for a group of listeners with normal hearing ranged from 3.5 degrees to 7.8 degrees (mean: 5.6 degrees ). When subjects listened in unilateral mode (with one device turned off), ? was at or near chance (50.5 degrees ) in all cases. However, when considering unilateral performance on each subject's better side, average ? for the speech stimulus was 47.9 degrees , which was significantly (but only slightly) better than chance. (2) When listening bilaterally, error score was significantly lower for the speech stimulus (mean ? = 21.5 degrees ) than for the noise stimulus (mean ? = 24.1 degrees ). (3) As a group, the 12 subjects who were retested 10 mo after their first visit showed no significant improvement in localization performance during the intervening time. However, two subjects who performed very poorly during their first visit showed dramatic improvement (error scores were halved) over the intervening time. In Experiment 2, removing the high-frequency content of noise signals resulted in significantly poorer performance, but removing the low-frequency content or increasing the rise-decay time did not have an effect. CONCLUSIONS: In agreement with previously reported data, subjects with bilateral cochlear implants localized sounds in the horizontal plane remarkably well when using both of their devices, but they generally could not localize sounds when either device was deactivated. They could localize the speech signal with slightly, but significantly better accuracy than the noise, possibly due to spectral differences in the signals, to the availability of envelope ITD cues with the speech but not the noise signal, or to more central factors related to the social salience of speech signals. For most subjects the remarkable ability to localize sounds has stabilized by 5 mo after activation. However, for some subjects who perform poorly initially, there can be substantial improvement past 5 mo. Results from Experiment 2 suggest that ILD cues underlie localization ability for noise signals, and that ITD cues do not contribute.     

Changes in speech breathing following cochlear implant in postlingually deafened adults

Three postlingually deafened adults who received cochlear implants read passages before and after their prostheses were activated while their lung volumes were measured with an inductive plethysmograph that transduced the cross-sectional areas of the speaker's chest and abdomen. Lung volumes at the initiation and termination of the speakers' expiratory limbs, their average air flow, and the volume of air they expended per syllable were derived from tracings of calibrated lung volume displayed by computer. The activation of the speakers' cochlear prostheses was followed in every case by a significant change in average airflow, which rose for two subjects with initially low flow rates and fell for one subject who had a much higher average preimplant flow rate. These changes in average flow rate were accompanied by corresponding changes in volume of air expended per syllable, statistically reliable in two of the three cases. There were no significant changes in the levels at which speakers initiated their expiratory limbs, but one speaker, after his prosthesis was activated, reliably increased the level of air in his lungs at the end of expiratory limbs to an average value that no longer required him to draw on expiratory reserve volume.     

Speech perception after multichannel cochlear implantation in Finnish-speaking postlingually deafened adults

This study was done to examine the short-term and long-term effects of multichannel cochlear implantation on speech perception in Finnish-speaking adults. The subjects comprise 20 adults. Pure-tone thresholds (0.125-8kHz), discrimination of phoneme quantity, sentence recognition, word recognition, phoneme recognition and listening performance were studied before and after implantation. After switch-on of the implant, the median pure-tone threshold values in the sound field were comparable to the level of mild hearing impairment. Most improvement in sentence recognition took place during the 6 months after the switch-on (mean score 74%). In word recognition, most improvement took place during the 12 months after the switch-on (mean score 66%), and clear improvement was noted even thereafter. In phoneme recognition, the performance of the subjects improved over the entire follow-up period, and 24 months after the switch-on the mean score was 52%. Individual variation was seen in the performance of the subjects. With 3 months of listening experience, all subjects were able to recognize some speech without speechreading, and they gained good functional benefit from the implant. The use of speech recognition tests with different degrees of difficulty is essential for the follow-up of adult cochlear implant subjects.     

Analysis of outcomes for communication mode in cochlear implant in prelingually deafened adults

ObjectiveRecent studies have suggested that speech perception outcomes after cochlear implantation (CI) in prelingually deafened adults have improved with advances in CI technology and speech processing strategies. However, the outcomes vary from case to case. Communication mode has been reported in many studies as the factor that related to the post CI outcomes. This study aimed at investigating the post CI outcomes and the progress during 2 years for each communication mode.Material and MethodsThe subjects were 17 prelingually deafened adults undergoing CI at our hospital between April 2013 and March 2019. We investigated preoperative factors affecting post CI outcomes. Also we analyzed post CI outcomes for each communication mode and compared preoperative factors for each communication mode.ResultsCommunication mode and preoperative discrimination score were the factor affecting on postoperative discrimination score. The speech perception score after CI improved significantly in the oral and lip-reading group and total communication group. The speech perception scores in postlingually deafened adults improved significantly during the first six months and became to plateau after CI. On the other hand, the scores of prelingually deafened adults tended to improve gradually after six months postoperatively. Furthermore, the degree of improvement and progress differed by each communication mode.ConclusionThe communication mode is important factors in predicting outcomes in prelingually deafened adults after CI. Long-term auditory training is important for prelingually deafened adults who use visual information as their preoperative method of communication.     

Performance of prelingually and postlingually deaf patients using single-channel or multichanel cochlear implants

The auditory and aided lipreading performance of 8 prelingually and 11 postlingually deaf patients who had received a single-channel or multichannel cochlear implant was evaluated during 2 years of follow-up. Although all the patients improved on both closed-set pattern recognition and speech drimination tests and on a Continouous Discourse Tracking task, the most significant improvement was observed in the postlingually deaf patients who were using a multichannel implant. These patients were the only ones to achieve open-set speech recognition in the auditory-only condition. Only small differences were found between prelingually deaf patients who were using a single-channel system and those who were using a multichannel system. The users' evaluations, obtained by means of a questionnaire, were generally positive in all patients. Based on the study results, the authors concluded that it is feasible to use cochlear implants in highly motivated prelingaully deaf patients who have learned to use oral-aural communication.     

Localization by postlingually deafened adults fitted with a single cochlear implant

OBJECTIVE:: The main purpose of the study was to assess the ability of adults with unilateral cochlear implants to localize noise and speech signals in the horizontal plane. DESIGN:: Six unilaterally implanted adults, all postlingually deafened and all fitted with MED-EL COMBI 40+ devices, were tested with a modified source identification task. Subjects were tested individually in an anechoic chamber, which contained an array of 43 numbered loudspeakers extending from -90 degrees to +90 degrees azimuth. On each trial, a 200 millisecond signal (either a noise burst or a speech sample) was presented from one of nine active loudspeakers, and the subject had to identify which source (from the 43 loudspeakers in the array) produced the signal. RESULTS:: The relationship between source azimuth and response azimuth was characterized in terms of the adjusted constant error (C). C for three subjects was near chance (50.5 degrees ), whereas C for the remaining three subjects was significantly better than chance (35 degrees -44 degrees ). By comparison, C for a group of normal-hearing listeners was 5.6 degrees . For two of the three subjects who performed better than chance, monaural cues were determined to be the basis for their localization performance. CONCLUSIONS:: Some unilaterally implanted subjects can localize sounds at a better than chance level, apparently because they can learn to make use of subtle monaural cues based on frequency-dependent head-shadow effects. However, their performance is significantly poorer than that reported in previous studies of bilaterally implanted subjects, who are able to take advantage of binaural cues.     

Psychoacoustic performance and music and speech perception in prelingually deafened children with cochlear implants

The number of pediatric cochlear implant (CI) recipients has increased substantially over the past 10 years, and it has become more important to understand the underlying mechanisms of the variable outcomes in this population. In this study, psychoacoustic measures of spectral-ripple and Schroeder-phase discrimination, the Clinical Assessment of Music Perception, and consonant-nucleus-consonant (CNC) word recognition in quiet and spondee reception threshold (SRT) in noise tests have been presented to 11 prelingually deafened CI users, aged 8-16 years with at least 5 years of CI experience. The children's performance was compared to the previously reported results of postlingually deafened adult CI users. The average spectral-ripple threshold (n = 10) was 2.08 ripples/octave. The average Schroeder-phase discrimination was 67.3% for 50 Hz and 56.5% for 200 Hz (n = 9). The Clinical Assessment of Music Perception test showed that the average complex pitch direction discrimination was 2.98 semitones. The mean melody score was at a chance level, and the mean timbre score was 34.1% correct. The mean CNC word recognition score was 68.6%, and the mean SRT in steady noise was -8.5 dB SNR. The children's spectral-ripple resolution, CNC word recognition, and SRT in noise performances were, within statistical bounds, the same as in a population of postlingually deafened adult CI users. However, Schroeder-phase discrimination and music perception were generally poorer than in the adults. It is possible then that this poorer performance seen in the children might be partly accounted for by the delayed maturation in their temporal processing ability, and because of this, the children's performance may have been driven more by their spectral sensitivity.     

Language and theory-of-mind development in prelingually deafened children with cochlear implants: a preliminary investigation

One cognitive domain in which deaf children are known to lag behind their hearing peers is that of 'theory of mind'. Impoverished early conversational experience and deprivation of discussion about intangible mental states are seen as likely contributors to this deficit. The present study explored the relation between language and theory-of-mind capabilities in prelingually deafened children aged 4 to 11 years who were cochlear implant users. The children completed theory-of-mind tasks that indexed their ability to reason about conflicting mental representations, namely the understanding of false belief and the distinction between appearance and reality. Controlling for age, language ability was found to correlate positively and reliably with theory-of-mind performance.     

Academic achievements and classroom performance in Mandarin-speaking prelingually deafened school children with cochlear implants

Objectives

To document academic achievements and classroom performance in 35 Mandarin-speaking, congenital/pre-lingual, deafened children who used cochlear implants (CIs) for 5–11 years. The possible associated factors were also analyzed.

Study design

Cross-sectional case series.

Methods

Standardized Chinese literacy ability and mathematics tests were administered to evaluate the academic achievement of these children. Raw scores derived from both literacy ability and mathematics tests were compared with normative data from children with normal hearing (NH). A modified Mandarin edition of the Screening Instrument for Targeting Educational Risk (SIFTER) and a Regular School Adjustment Scale (RSAS) for students with hearing impairments filled out by regular classroom teachers were used to assess the children's classroom performances.

Results

The mean standard T-scores for Chinese literacy ability and mathematics ability were 48.6 and 50.3 (NORM = 50 ± 10), respectively. A total of 85.7% of children with CIs scored within or above the normal range of their age-matched hearing peers in Chinese literacy ability, and 82.9% were within normal ranges in mathematics ability. The SIFTER results showed that 45.7% failure was noted on the communication subscale, and the RSAS also indicated 40% of CI students to have communication problems. The academic subscale scores on the SIFTER were associated with the children's Chinese literacy abilities. The Verbal Comprehension Index (VCI) of the Wechsler IQ test IV was related to the children's mathematics abilities.

Conclusions

The academic achievements of Mandarin-speaking children who receive CIs from a young age and are integrated into mainstream elementary school system appear to fall within the normal range of their age-matched hearing counterparts after 5–11 years of use. This study strongly suggests the need for future ongoing support for these children in communication field.     

Non-use of cochlear implants by post-lingually deafened adults

Abstract

Objectives To document the occurrence of medical/surgical complications in the provision of cochlear implants to a cohort of post-lingually deafened adult patients; to compare cumulative mortality in the cohort with cumulative mortality predicted from an aged-matched control population; to relate the occurrence of medical/surgical complications to the patient's position in the case series; to identify risk factors for elective non-use of implants; and to examine the impact of complications, mortality and elective non-use on the cost of creating a successful user of a cochlear implant

Design Longitudinal prospective observational study.

Setting Nine hospitals in the UK, which received central funding between 1990 and 1994 to participate in a programme of adult implantation.

Participants All 313 post-lingually deafened adults who received multichannel cochlear implants in this programme.

Main outcome measures Status of patients in July 1998 (dead, an elective non-user or a user); duration of use prior to death or elective non-use; costs of creating and sustaining a successful user; ability to identify environmental sounds; self-reported benefit.

Results Cumulative mortality after 7.5 years was 6.3% (95% CI 2.5?10.1%) and was no different from cumulative mortality predicted from life expectancy in the general population. Cumulative elective non-use was stable at 6.3% (95% CI 3.6%?9.1%) between 4 and 7 years after implantation but rose to 11.0% (95% CI 1.7%?20.3%) at 7.5 years after implantation. Major medical/surgical complications were experienced by 25/313 patients (8.0%). The occurrence of such complications declined to ca. 1% over the first 50 cases in a hospital's case series. For patients who were users, self-reported benefit did not differ between patients who had experienced complications and those who had not. Older age at implantation, greater duration of deafness prior to implantation or an early position in a hospital's case series were not significant risk factors for elective non-use. Experiencing a major complication was a marginally significant risk factor (odds ratio = 3.2, 95% CI 1.0?10.6). Low auditory performance (odds ratio = 8.2, 95% CI 2.1?31.9) and low self-reported benefit (odds ratio = 19.6, 95% CI 4.6?84.4) were significant risk factors. Medical/surgical complications raised the cost of creating a successful user by less than 1%. Elective non-use raised the cost by between 5% and 10%.

Conclusions Medical/surgical complications were generally managed successfully without detriment to benefit; life expectancy in the general population can be used to predict the length of time for which patients have the potential to use cochlear implants; patients who experience little benefit are most at risk for elective non-use; given the high cost of cochlear implantation, benefit should be monitored to allow early rehabilitative intervention in cases of low benefit; patient cohorts such as the present one should continue to be followed up with a view to identifying pre-operative risk factors for elective non-use.     

Lexical tone recognition in noise in normal-hearing children and prelingually deafened children with cochlear implants

Abstract

Objective: The purpose of the present study was to investigate Mandarin tone recognition in background noise in children with cochlear implants (CIs), and to examine the potential factors contributing to their performance. Design: Tone recognition was tested using a two-alternative forced-choice paradigm in various signal-to-noise ratio (SNR) conditions (i.e. quiet,?+12,?+6, 0, and ?6?dB). Linear correlation analysis was performed to examine possible relationships between the tone-recognition performance of the CI children and the demographic factors. Study sample: Sixty-six prelingually deafened children with CIs and 52 normal-hearing (NH) children as controls participated in the study. Results: Children with CIs showed an overall poorer tone-recognition performance and were more susceptible to noise than their NH peers. Tone confusions between Mandarin tone 2 and tone 3 were most prominent in both CI and NH children except for in the poorest SNR conditions. Age at implantation was significantly correlated with tone-recognition performance of the CI children in noise. Conclusions: There is a marked deficit in tone recognition in prelingually deafened children with CIs, particularly in noise listening conditions. While factors that contribute to the large individual differences are still elusive, early implantation could be beneficial to tone development in pediatric CI users.