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PubMed2006

Examining the communication skills of a young cochlear implant pioneer.

The purpose of this longitudinal case study was to closely examine one deaf child's experience with a cochlear implant and his speech, language, and communication skills from kindergarten through middle and high school using both developmental and sociocultural frameworks. The target child was one of the first children to receive a cochlear implant in the United States in 1988, when he was 5 years of age. The developmental analysis revealed that prior to receiving a cochlear implant the child demonstrated profound delays in speech and language skill development. His speech and language skills grew slowly during the first 3-4 years following implantation, very rapidly from about 5 through 7 years postimplantation, then slowed to rates that were highly similar to same-age peers with normal hearing. The sociocultural analysis revealed that the child's communicative competence improved; that he used sign language but use of sign language decreased as his oral communication skills improved; that as his oral communication skills improved, the adults talked and directed the topic of conversation less frequently; and that topics became less concrete and more personal over time. The results of this study indicate that we may learn more about how to support children who use cochlear implants by examining what they are saying as well as how they are saying it.

Adolescent↗
PubMed2002

The effect of channel interactions on speech recognition in cochlear implant subjects: predictions from an acoustic model.

Acoustic models that produce speech signals with information content similar to that provided to cochlear implant users provide a mechanism by which to investigate the effect of various implant-specific processing or hardware parameters independent of other complicating factors. This study compares speech recognition of normal-hearing subjects listening through normal and impaired acoustic models of cochlear implant speech processors. The channel interactions that were simulated to impair the model were based on psychophysical data measured from cochlear implant subjects and include pitch reversals, indiscriminable electrodes, and forward masking effects. In general, spectral interactions degraded speech recognition more than temporal interactions. These effects were frequency dependent with spectral interactions that affect lower-frequency information causing the greatest decrease in speech recognition, and interactions that affect higher-frequency information having the least impact. The results of this study indicate that channel interactions, quantified psychophysically, affect speech recognition to different degrees. Investigation of the effects that channel interactions have on speech recognition may guide future research whose goal is compensating for psychophysically measured channel interactions in cochlear implant subjects.

Acoustic Stimulation↗
PubMed2002

Recognition of lexically controlled words and sentences by children with normal hearing and children with cochlear implants.

OBJECTIVE: The purpose of this study was to investigate the combined lexical effects of word frequency and neighborhood density (acoustic-phonetic similarity) on the recognition of words spoken in isolation and words spoken in sentences for children with normal hearing and children with cochlear implants. DESIGN: Lexically controlled sentences were created from a subset of words obtained from the spoken vocabulary of children between the ages of 3 and 5 yr. Two sentence lists were generated, applying the definitions and procedures of Kirk, Pisoni, and Osberger (1995) in accordance with the Neighborhood Activation Model ( Luce, 1986; Luce & Pisoni, 1998). One list was composed of lexically "easy" words (those high in frequency of occurrence but phonemically dissimilar to other words) and the other list was composed of lexically "hard" words (those low in frequency of occurrence but phonemically similar to other words). Each list consisted of five practice and 20 test sentences that were syntactically correct but semantically neutral (low in predictability). Three key words were used in constructing each of the 5- to 7-word sentences, resulting in 15 practice and 60 key words per test list. In the first of three experiments, 48 normal-hearing children between the ages of 5 and 12 yr were asked to repeat the words and sentences at one of six presentation levels to establish performance-intensity functions. In the second experiment, 12 normal-hearing children between the ages of 5 and 14 yr repeated the words and sentences under spectrally degraded conditions. Twelve children with cochlear implants ages 5 to 14 yr repeated the unprocessed stimuli in a third experiment. RESULTS: The lexically easy stimuli were recognized with greater accuracy than the lexically hard stimuli for the children tested in all three experiments. Sentence scores were significantly higher than word scores for the normal-hearing children (Experiments 1 and 2) and nine high-performing children with cochlear implants (Experiment 3). Word scores were higher than sentence scores for the three low-performing children with cochlear implants. There was a statistically significant relationship between chronological age and sentence score for the normal-hearing children listening under spectrally degraded conditions. For the children with cochlear implants, the relationship between language quotient and sentence and word scores was statistically significant. CONCLUSION: Sensitivity to the combined lexical properties of word frequency and neighborhood density was evident both for words and sentences. Lexically easy stimuli were recognized with greater accuracy than lexically hard stimuli across groups, affirming the robustness of this effect and verifying that words were being organized in relation to the frequency and acoustic-phonetic properties of other words. Syntactic context facilitated word recognition for the children with normal hearing and the high-performing implant group. The three low-performing children with cochlear implants recognized words more accurately than sentences, reflecting limitations in linguistic and cognitive capacity.

Child, Preschool↗
PubMed2002

Outcome of cochlear implantation at different ages from 0 to 6 years.

OBJECTIVE: To evaluate the outcome of cochlear implantation in young children in relation to the age at implantation. STUDY DESIGN: A retrospective longitudinal and cross-sectional analysis of pediatric cochlear implant patients. PATIENTS: All children with congenital deafness who underwent implantation before the age of 6 years (n = 48 for the longitudinal analysis and n = 70 for the cross-sectional analysis) INTERVENTIONS: All children received a multichannel cochlear implant. MAIN OUTCOME MEASURES: Categories of Auditory Performance (CAP) score and integration into the mainstream school system. RESULTS: For all children, the CAP score increased after implantation. Implantation beyond the age of 4 years hardly ever resulted in normal CAP scores or in integration into the mainstream primary school (20 to 30% of cases). Implantation between the age of 2 and 4 years always resulted in normal CAP scores after 3 years with a 66% probability of integration into the primary school. Implantation before the age of 2 years always resulted in immediate normalization of the CAP scores, with a 90% probability of integration into the mainstream kindergarten, well before entrance into the primary school. CONCLUSION: All children with congenital deafness who underwent implantation before the age of 6 years appeared to benefit from the implant. However, these data add evidence to the importance of early implantation (before the age of 2 years). Intervention before the age of 4 years seemed to be critical to avoid irreversible auditory performance losses, and intervention before the age of 2 years seemed to be critical to achieve optimal results.

Age Factors↗
PubMed1998

Cochlear implantation. Practical information for the generalist.

The diagnosis and investigation of a patient with bilateral, severe-to-profound sensorineural hearing loss is presented. The steps toward cochlear implantation, including tests of audition, balance, radiographic imaging, and the pre- and postrehabilitation period, are reviewed. The two major cochlear implants available today, and future developments within the cochlear implant, are presented.

Audiometry↗
PubMed2006

[Cochlear implant or regular hearing aid?].

A significant number of deaf patients that have received cochlear implants now achieve higher word recognition scores then those with conventional auditory prostheses. This situation makes the choice of which type of auditory rehabilitation to propose a complex matter in patients with remaining auditory function. Our paper aims at providing some arguments to these new questions by presenting the clinical experience and practice of the Centre romand d'implants cochléaires. We also address related legal issues. Clinical tools, such as testing the comprehension of lists of logatoms have proved very useful for the evaluation of these particular patients. The evaluation of cochlear implant candidates remains a highly individualized process, necessitating a case by case approach by an experienced multidisciplinary cochlear implant team.

Cochlear Implants↗
PubMed2006

Change of phonation control after cochlear implantation.

OBJECTIVE: To assess the influence of acquired auditory control on some voice parameters in deaf children and adults after cochlear implantation. STUDY DESIGN: Prospective clinical study. SETTING: Tertiary referral center. PATIENTS: Twenty-nine prelingually deafened children and 11 postlingually deafened adults. INTERVENTIONS: The samples of a vowel /a/ were analyzed with an Multi-Dimensional Voice Program (Kay Elemetrics Corporation, Lincoln Park, NJ) before and 6 to 12 months after the cochlear implantation. MAIN OUTCOME MEASURES: The average fundamental frequency (F0), the short-term variation of F0 (JIT) and the amplitude (SH), the very long-term variation of F0 (vF0) and the amplitude (vAm), and the noise-to-harmonic ratio (NHR) were determined and compared for both age groups. The results of the acoustic analysis performed before the implantation were compared with the results after the implantation for children and adults. RESULTS: Significantly greater JIT, SH, vF0, and vAm were detected in the children than in the adults before and after the implantation. The prelingually deafened children significantly improved the control of their phonation after 6 to 12 months' use of the cochlear implant (JIT: p=0.014, SH: p=0.011, vF0: p=0.014, vAm: p=0.031). In the postlingually deafened adults, no significant improvement was found in any of the studied voice parameters after the implantation. F0 showed little or no change after the implantation in children and adults. CONCLUSION: As expected, the voice quality of the prelingually deafened children was significantly worse than that of the postlingually deafened adults. After cochlear implantation, the children significantly improved their short-term and long-term F0 and amplitude variability. In adults, no significant improvement was detected. We suppose that the improvement is a consequence not only of the acquired hearing control but also of the adaptation ability of neuromuscular phonation control and the maturing of these control mechanisms in children. In adults, better phonation quality in general and lesser improvement after the implantation can be the results of well-developed and stable phonation patterns.

Adolescent↗
PubMed1990

Forward masking in patients with cochlear implants.

Forward masking was measured in 12 patients with cochlear implants. The amount of masking (in microamps) decreased linearly as a function of the logarithm of the signal delay from masker offset. Normalized forward-masking recovery functions for cochlear implants were similar to normalized functions of normal-hearing listeners, indicating that the mechanism of psychophysical forward masking is retrocochlear. These results indicate that the logarithm of acoustic amplitude should be mapped to microamps to produce normal forward masking in implanted patients. Despite the fact that the forward-masking recovery functions were similar across all patients, their performance with their speech processor varied widely.

Attention↗
PubMed1998

Basal turn cochleostomy via the middle fossa route for cochlear implant insertion.

OBJECTIVE: The current article describes the surgical technique and the very preliminary results of insertion of a cochlear implant, via the middle fossa (MF), in patients with middle ear disease. STUDY DESIGN: The study design was a case report and a description of surgical technique. SETTING: The study was conducted at an ENT Department, University of Verona, Verona, Italy. PATIENTS: Two subjects with profound bilateral hearing loss, the first one presenting a bilateral radical mastoidectomy cavity and the second one with fibroadhesive otitis media, were operated on via the current technique. INTERVENTION: After adequate exposure of the MF floor, a triangular bony area between the greater superficial petrous nerve and the projection of the labyrinthine portion of the facial nerve was drilled out. The basal cochlear turn facing the middle cranial fossa floor was easily encountered, a small cochleostomy measuring 1 1/2 mm in diameter was performed on the most superficial part of the basal turn, and the electrode carrier was inserted into the fenestrated cochlea. The receiver-stimulator was positioned on a bone well drilled previously in the temporal squama. MAIN OUTCOME MEASURES: The activity of the inserted electrodes was tested by means of telemetry and intraoperative recording of the electrically evoked auditory responses. Speech perception tests, performed 15 and 30 days after cochlear implant activation, showed a remarkable improvement in the outcomes versus the preoperative values that are provided for comparison. CONCLUSIONS: This new surgical approach to cochlear implant insertion via the MF route allows stimulation of part of the basal and the middle and apical areas of the cochlea, where greater survival rates of spiral ganglion cells are observed. Cochlear implant insertion via the MF approach represents a promising technique for auditory rehabilitation of subjects with a bilateral radical mastoidectomy cavity, patients suffering from middle ear malformations or chronic middle ear disease due to eustachian tube dysfunction, or subjects with doubtful responses to promontory stimulation.

Aged↗
PubMed2001

Value of high-resolution MR in patients scheduled for cochlear implantation.

OBJECTIVE: To determine sensitivity and specificity of high-resolution MR imaging and of high-resolution axial CT (HRCT) and to compare the two modalities in predicting the surgical and functional success of cochlear implantation. MATERIAL AND METHODS: The presurgical MR images (2D T2W TSE, 3D T2*W CISS, plain and contrast-enhanced 3D T1W MP-RAGE) and axial HRCT findings of 26 patients were evaluated with regard to the predictive value concerning the success of cochlear implantation. RESULTS: We found a high correlation between MR and HRCT and the success of cochlear implantation. In all 26 patients, the MR-based predictions concerning the success of cochlear implantation were correct. In 10 patients, MR gave additional information to HRCT. In all patients, MR gave sufficient information about the status of the inner ear, inner auditory canal and cochlear nerve to aid the surgeon during the operation. CONCLUSION: A high-resolution MR protocol consisting of coronal 2D T2W TSE, 3D T2*W axial CISS, plain and contrast-enhanced sagittal T1W 3D MP-RAGE is recommended for the evaluation of candidates scheduled for cochlear implantation. It provides information which cannot be obtained by HRCT.

Adolescent↗
PubMed1997

Speech perception by prelingually deaf children using cochlear implants.

In this investigation we measured the performance of 50 prelingually deaf children on several speech perception tests. Children were from 2 to 15 years of age, and some children were tested with as much as 5 years of cochlear implant use. Speech perception tests included the recognition of stress pattern, consonants, vowels, words, and sentences. The audiovisual perception of consonants was also measured. Average results indicated that gains were being made in the perception of stress and words in a closed-set context within 1 year from implantation. The perception of words in an open-set context demonstrated much slower increases over time. Large individual differences were observed. Some preliminary data suggest that children who receive implants before the age of 4 years obtain higher scores, on average, than children who receive implants after the age of 5 years. Some children become part-time users or nonusers of their cochlear implants. The average results from 18 congenitally deaf children were significantly higher than the average results from 12 children with prelingually acquired deafness after 3 years of implant use. Information on vowel and consonant features shows increases in performance after 2 years of cochlear implant use, with the exception of the place feature. For this feature, no changes were observed. Vision-alone testing indicated that lipreading performance increased over time. An audiovisual enhancement provided by the cochlear implant was observed for all features.

Adolescent↗
PubMedDate not supplied

Outcomes of cochlear implantation in children with auditory neuropathy.

Ten children who were diagnosed with auditory neuropathy were matched with ten children who were diagnosed with other etiologies. All twenty children received cochlear implants at the Mayo Clinic in Rochester, Minnesota. Various measures were used to compare the outcomes for the two groups. We compared the children's unaided and aided audiograms, and measures of threshold and comfort levels. Performance on age appropriate speech perception tests was measured. Electrically elicited auditory brainstem response, predicted Neural Response Telemetry thresholds, and visually detected electrical stapedius reflexes were compared. Parental report of cochlear implant benefit was evaluated using either the Meaningful Auditory Integration Scale or the Infant-Toddler Meaningful Auditory Integration Scale depending on the age of the child. We also compared educational placement and communication mode. The results of this study demonstrated that there were no important differences in cochlear implant benefit between the two groups. In light of these findings, we support the use of cochlear implants as a viable option for selected children with auditory neuropathy.

Auditory Threshold↗
PubMed1996

Learning disability in children with postmeningitic cochlear implants.

OBJECTIVE: To determine the effects of learning disability on measures of auditory perception, receptive language development, and sequential organization in children with postmeningitic cochlear implants. DESIGN: Retrospective study. Follow-up ranged from 12 months to 7 years. SETTING: Tertiary care center. PATIENTS: Ten pediatric patients with cochlear implants, 5 with documented learning disability. MAIN OUTCOME MEASURE: Pediatric cochlear implant test battery performance. RESULTS: Children with learning disability showed slower progress, more inconsistencies, and lower test scores than their partners without learning disability. CONCLUSION: Learning disability is not a contraindication to cochlear implantation, but preoperative counseling must be available to families and support personnel about preoperative achievements and expectation for these children.

Child↗
PubMedDate not supplied

Methods and issues in the cochlear implantation of children: an overview.

The single-electrode cochlear implant is undergoing clinical trials in children under Federal Food and Drug Administration regulations governing medical devices. Seven teams from around the United States are participating in this investigation as coinvestigators with the House Ear Institute. The clinical research program involves evaluation and selection for an implant surgery, basic guidance for fitting the device, and follow-up monitoring on a regular basis. As of December 31, 1984, 164 profoundly deaf children have received the cochlear implant. They ranged in age at time of surgery from 2 yr, 5 mo to 17 yr, 11 mo. The majority of children were deafened from bacterial meningitis (N = 98). The pertinent issues involved in the implantation of children include methods of investigation, impact of deafness, potential risks and benefits, and alternatives. While the use of the implant in children continues to be controversial, the evidence to date indicates that this prosthesis can provide significant benefit for a select population of profoundly deaf children.

Adolescent↗
PubMed1993

The effects of auditory feedback from the nucleus cochlear implant on the vowel formant frequencies produced by children and adults.

Cochlear implants provide an auditory signal with which profoundly deaf users may monitor their own speech production. The vowel production of two adults and three children who used the Nucleus multiple-electrode cochlear implant was examined to assess the effect of altered auditory feedback. Productions of words were recorded under conditions where the talkers received auditory feedback (speech processor turned on) and where no auditory feedback was provided (speech processor turned off). Data were collected over 3 days at weekly intervals. First and second formant frequencies were measured and the data were analysed to assess significant differences between auditory feedback conditions, vowel context, and data collection points. Overall, the results varied across talkers, across the data collection days, and depended on the consonant environment of the vowel. However, two effects of auditory feedback were noted. First, there was a generalized shift in first formant frequencies between the processor on and processor off conditions across three of the five subjects, but the shift differed in direction for each subject. Second, for three of the five talkers, the two front vowels /epsilon/ and /i/ were more neutralised in the absence of auditory feedback. However, this effect was less pronounced than that noted by previous studies.

Aged↗
PubMed2006

[Micro-focus X-ray for cochlear implantation research on small animals].

OBJECTIVE: To develop an imaging system suitable for cochlear implant research on small laboratory animals. METHODS: A novel micro-focus X-ray imaging system was developed. The key features of the system were the use of a micro-focus X-ray source (less than 10 micrometers) and an appropriate choice of source-object and object-image distance. The new X-ray modality was evaluated on heads of cats, guinea pigs and rats. RESULTS: It proved to be an useful tool to provide excellent image of small animal cochlea, allowing a clear electrode position to be established, and also helped greatly in detecting the breakage of electrode array. CONCLUSIONS: Experimental studies performed in cats, guinea pigs and rats confirmed that micro-focus radiography was an important tool for cochlear implant research in laboratory

Animals↗
PubMed1991

Predictors of cochlear implant use in children.

The purpose of this study was to identify predictors of effective use of a cochlear implant in a sample of 29 profoundly deaf children, who had been using their devices an average of 2 years. The relationship between the variables of age of onset of deafness, etiology, and communication mode measured prior to implant surgery were correlated with a behavioral measure of cochlear implant use in everyday situations. In addition, in a subset of the full sample, nonverbal intelligence subtest scores calculated prior to implant surgery were evaluated for their contribution to subsequent use of the cochlear implant. The results suggested that communication mode, time using the implant device, and performance on two subsets from the Wechsler Intelligence Scale for Children-Revised (WISC-R) accounted for substantial proportions of the variance in parent ratings of implant usage. The implications of these findings, as well as directions for future research, are discussed.

Adolescent↗