Evidence of Vestibular and Balance Dysfunction in Children With Profound Sensorineural Hearing Loss Using Cochlear Implants

from Laryngoscope

Abstract:
Objectives/Hypothesis: Similarities between the peripheral auditory and vestibular systems suggest that children with sensorineural hearing loss (SNHL) may demonstrate vestibular and balance impairments. This hypothesis was studied in 40 children with severe to profound SNHL and unilateral cochlear implants.

Study Design: Prospective cross-sectional study with repeated measures.

Methods: Vestibular function was assessed with caloric, rotational, and vestibular evoked myogenic potential testing; balance was assessed using the balance subset of the Bruininks-Oseretsky Test of Motor Proficiency-II, a standardized test of static and dynamic balance.

Results: Horizontal semicircular canal function was abnormal in response to a caloric stimulus in 50% (16/32), with a large proportion of those [6/16 (38%)] reflecting mild to moderate unilateral abnormalities. In comparison, horizontal semicircular canal function in response to rotation was abnormal in 38% (14/37). Saccular function was absent bilaterally in 5/26 (19%) and unilaterally in 5/26 (19%) with vestibular evoked myogenic potential. Age standardized balance abilities were significantly poorer in the study population [[mu] = 12.9 +/- 5(SD)] compared with normal hearing controls [[mu] = 17 +/- 5(SD); P = .0006] and correlated best with horizontal canal function in response to a rotational stimulus (P = .004; R2 = 0.24). SNHL from meningitis was associated with worse balance function than other etiologies.

Conclusions: Vestibular and balance dysfunction occurred in >1/3 of children with SNHL and cochlear implants, and is highly dependent on etiology. Although compliance with all tests was high, rotational chair testing, which assesses higher frequency motion (0.25-5 Hz) and thus more “real world” vestibular function, correlated best with dynamic balance. For this reason, rotational chair testing may represent the test of choice in this population, particularly given that it is amenable to testing children of all ages.

Assessment of Speech Recognition for HI and CI Patients: Things Need to Change

from the National Health Service (UK)

Abstract: Hearing aid and cochlear implant technologies have changed over the years, but the audiological assessment of speech recognition has not kept pace with the need to provide better assessment tools. This presentation will highlight some of the more recent findings and recommended procedures that provide more comprehensive assessments of speech recognition in quiet and various background noise environments.

For further information contact:

Tel : 0115 942 1985
Fax : 0115 924 9054

http://www.earfoundation.org.uk/contact/

Register at:

http://www.hearingseminars.com/jonshallop2008/event/registration.html

Where:Nottingham
When:06 Nov 2008 17:30 - 19:00

Neural tonotopy in cochlear implants: an evaluation in unilateral cochlear implant patients with unilateral deafness and tinnitus

from Hearing Research

Article in press. No abstract available.

Effect of Preoperative Residual Hearing on Speech Perception After Cochlear Implantation

from Laryngoscope

OBJECTIVE:: To assess the effect of substantial preoperative residual hearing on speech perception outcomes in adult cochlear implant recipients. SETTING:: Tertiary care academic referral center. METHODS:: Twenty-nine patients with substantial preoperative residual hearing underwent cochlear implantation. Twenty-one implant recipients matched for age and duration of hearing loss, but without preoperative residual hearing, served as controls. Postoperative speech perception was assessed using City University of New York sentence, consonant-nucleus-consonant, and hearing in noise test in quiet and in noise (+10 dB signal to noise ratio) tests at 1, 3, 6, and 12 months after fitting. RESULTS:: After implantation, there were no significant differences between groups for any of the tests administered. The mean change in speech perception abilities from baseline was significantly greater for the control patients than those with substantial preoperative residual hearing at a number of the test intervals across the various conditions. Moreover, at both 1 and 3 months, some patients in the residual hearing group had speech perception scores that were worse than their preoperative values. Ultimately, all of the patients with substantial residual hearing surpassed their preoperative performance. DISCUSSION:: Patients with substantial preoperative residual hearing can gain significant benefit from cochlear implantation. Although the degree of improvement in these individuals is somewhat more modest than for those patients without preoperative residual hearing, the outcomes are still excellent. That there were no significant differences between the patient groups suggests that having substantial residual hearing before implantation does not provide a measurable performance advantage for electrical stimulation. Patients with substantial residual hearing who are contemplating cochlear implantation should be counseled regarding a possible initial decline in speech perception performance.

Biopolymer-Released Dexamethasone Prevents Tumor Necrosis Factor [alpha]-Induced Loss of Auditory Hair Cells In Vitro: Implications Toward the Development of a Drug-Eluting Cochlear Implant Electrode Array

from Otology & Neurotology

Hypothesis: Polymer-eluted dexamethasone (DXM) will retain its ability to protect against tumor necrosis factor [alpha] (TNF[alpha])-induced hair cell (HC) loss.

Background: TNF[alpha] has been shown to be associated with trauma-induced hearing loss. DXM has been demonstrated to protect the cochlea against trauma-induced hearing loss. DXM is currently administered either systemically or locally to treat patients with sudden hearing loss of unknown cause.

Methods: P-3 organ of Corti explants challenged with an ototoxic level of TNF[alpha] was the experimental system, and the base form of DXM (DXMb) incorporated into a biorelease polymer (i.e., SIBS) was the otoprotection molecule tested. The efficacy of otoprotection was determined by counts of fluorescein isothiocyanate-phalloidin-stained HCs and changes in gene expression.

Results: HC counts show 1) SIBS alone did not protect HCs from TNF[alpha] ototoxicity (SIBS versus SIBS + TNF[alpha]; p < 0.001), and 2) SIBS with DXMb provides a significant level of protection against TNF[alpha]-induced loss of HCs (TNF[alpha] + SIBS versus TNF[alpha] + SIBS/DXMb, 299 [mu]g; p < 0.001). Gene expression results show that polymer-eluted DXMb 1) upregulates antiapoptotic genes (i.e., Bcl-2, Bcl-xl) and downregulates a proapoptotic gene (i.e., Bax) in TNF[alpha]-challenged explants and 2) downregulates TNFR1 in these explants.

Conclusion: Polymer-eluted DXMb retains its otoprotection capabilities in our in vitro test system of TNF[alpha]-challenged organ of Corti explants by altering the pattern of gene expression to favor survival of TNF[alpha]-exposed HCs. These results, although in vitro, support the application of polymer containing DXMb to electrode arrays for the conservation of hearing during cochlear implantation.

Cochlear implants in children a safe procedure

from EurekAlert.org

Chicago, IL – In the six decades since French and American surgeons implanted the first cochlear hearing devices, the procedure in children has become reliable, safe, and relatively free of severe complications, according to research presented during the 2008 American Academy of Otolaryngology-Head and Neck Surgery Foundation (AAO-HNSF) Annual Meeting & OTO EXPO, in Chicago, IL.

The effect of temporal gap identification on speech perception by users of cochlear implants

from the Journal of Speech, Language, and Hearing Research

Purpose: This study examined the ability of listeners using cochlear implants (CIs) and listeners with normal-hearing (NH) to identify silent gaps of different duration, and the relation of this ability to speech understanding in CI users.

Method: Sixteen NH adults and eleven postlingually deafened adults with CIs identified synthetic vowel-like stimuli that were either continuous or contained an intervening silent gap ranging from 15 to 90 ms. Cumulative d’, an index of discriminability, was calculated for each participant. Consonant and CNC word identification tasks were administered to the CI group.

Results: Overall, the ability to identify stimuli with gaps of different duration was better for the NH group than for the CI group. Seven CI users had cumulative d’ scores that were no higher than those of any NH listener, and their CNC word scores ranged from 0 to 30%. The other four CI users had cumulative d’ scores within the range of the NH group, and their CNC word scores ranged from 46% to 68%. For the CI group, cumulative d’ scores were significantly correlated with their speech testing scores.

Conclusions: The ability to identify silent gap duration may help explain individual differences in speech perception by CI users.

New tool to assess speech development in infants, toddlers with hearing impairments

from EurekAlert.org

The number of hearing impaired infants and toddlers who are successfully aided by technological devices, such as hearing aids and cochlear implants, continues to grow, but there are still unknowns about these children’s speaking abilities, according to a Purdue University expert.

Modifications of standard cochlear implantation techniques for children under 18 months of age

from Cochlear Implants Internations

Cochlear implantation is being performed in increasingly younger children. We present a retrospective cohort of 19 patients with 23 ears implanted under 18 months of age. The mean age at implantation was 11.9 months, with the youngest being 6.8 months. The facial recess was narrow in nine ears (39%), including all premature infants. An inferiorly located stapedius tendon was sectioned in seven ears (30%) to facilitate round window access. Countersinking of the receiver-stimulator required dural exposure in 22 ears (96%). The receiver-stimulator was secured with sutures in 15 ears (65%) and within a tight pocket in eight ears (35%). Tympanostomy tubes were placed in 10 ears (43%). Cochlear implantation in very young children frequently necessitates modified surgical techniques. Copyright © 2006 John Wiley & Sons, Ltd.

Theory of Mind and Language in Children With Cochlear Implants

from the Journal of Deaf Studies and Deaf Education

Thirty children with cochlear implants (CI children), age range 3–12 years, and 30 children with normal hearing (NH children), age range 4–6 years, were tested on theory of mind and language measures. The CI children showed little to no delay on either theory of mind, relative to the NH children, or spoken language, relative to hearing norms. The CI children showed a slightly atypical sequence of acquisition of theory of mind concepts. The CI children’s theory of mind performance was associated with general syntactic proficiency more than measures of complement syntax, and with time since implantation more than age at implantation. Results suggest that cochlear implantation can benefit spoken language ability, which may then benefit theory of mind, perhaps by increasing access to mental state language.

Ear selection and pediatric cochlear implants: A preliminary examination of speech production outcomes

from the International Journal of Pediatric Otorhinolaryngology

Objective
The goal of the current study was to examine whether ear selection (left versus right) for cochlear implantation results in significant differences in speech production outcomes.

Methods
Ten children with right-ear implants were compared to five children with left-ear implants on intelligibility of speech produced in single words, sentences, and conversation as well as on accuracy of speech sounds produced during administration of a single word articulation test and in conversational speech.

Results
The children with right-ear implants performed significantly better than those with left-ear implants but only on the single word tasks. No significant differences were observed at the sentence or conversational speech levels.

Conclusion
Findings are discussed relative to the possibility that the obtained ear of implantation differences (if real) may disappear over time. Such a conclusion is quite tentative however given the small sample size in the current study. Such a limitation may also explain why no differences were obtained for the connected speech measures. Further study of ear selection outcomes is clearly indicated.

The Electrically Evoked Auditory Change Complex: Preliminary Results from Nucleus Cochlear Implant Users

from Ear and Hearing

Abstract:
Objectives: The purpose of this study was to determine if changes in the position of the stimulating electrode in the cochlea could be used to elicit the electrically evoked auditory change complex (EACC) from Nucleus cochlear implant users.

Design: Nine postlingually deafened adults participated in this study. Each study participant had been using his or her Nucleus CI24 cochlear implant for at least 3 mos before testing. The speech processor was bypassed and the output of the implanted receiver/stimulator was controlled directly. The stimulus was a 600 msec burst of a biphasic pulse train (1000 pps). In control conditions, the stimulating electrode was held constant and stimulation continued throughout the 600 msec recording interval. In experimental conditions, the EACC was elicited by introducing a change in the stimulating electrode 300 msec after the onset of the pulse train. The EACC was recorded using surface electrodes. Three recordings of 100 sweeps each were obtained for each stimulus condition. Bandpass filtering (1-100 Hz) was used to minimize contamination of the recordings by stimulus artifact. Averaged responses were then smoothed using a 40-msec wide boxcar filter and standard peak picking procedures were used to analyze these responses in the time domain.

Results: In each case, a clear onset response (P1-N1-P2) was recorded. In the experimental conditions, a second evoked potential, the EACC, was also recorded after the change in stimulating electrode. This second response had general morphological characteristics that were very similar to those of the onset response. Increasing the separation between the two stimulating electrodes in the experimental conditions resulted in a general trend toward increased EACC amplitudes.

Conclusions: This report describes results of a set of experiments in which the speech processor of the cochlear implant was bypassed and the EACC was recorded in response to a change in stimulating electrode position. EACC amplitude was shown to increase as the separation between the two stimulating electrodes increased. Although preliminary in nature, these results demonstrate the feasibility of recording the EACC in response to changes in stimulating electrode position from individual cochlear implant users.

An evaluation of the preservation of residual hearing with the Nucleus® Contour Advance™ electrode

from Acta Oto-Laryngologica

Abstract
Conclusion. Our study results confirm that it is possible to preserve preoperative hearing levels in the majority of subjects when using the Nucleus 24 Contour Advance provided that there is adherence to the major principles of ’soft surgery’. Our study group demonstrated that 71-86% of subjects showed preservation of preoperative hearing thresholds at 6 months to varying degree. Objectives. The aim of the study was to assess the degree of residual hearing preserved postoperatively in a group of standard cochlear implant (CI) candidates following implantation via soft surgery with a Nucleus® 24 Contour Advance™ CI. Surgical technique variations from the soft surgery guidelines provided were assessed and their potential impact upon the conservation of residual hearing was examined. Subjects and methods. A prospective multicentre study involving a within-subject repeated measures design with each subject acting as their own control was performed. Pure-tone audiometric thresholds were assessed and compared in both implanted and contralateral ears for each subject preoperatively as baseline measures and at 6 months postoperatively. Surgeons were asked to complete a questionnaire to capture various aspects of the surgical technique used for each subject. Variations in the surgical technique performed were examined for potential correlation with conservation of residual hearing. Twenty-eight adult subjects, with a severe to profound hearing impairment, were enrolled in the study across eight implant clinics in four countries. Results. In all, 36% of subjects demonstrated preservation of thresholds to within 10 dB of preoperative thresholds across the frequency range (0.25, 0.5, 1.0, 2.0 and 4.0 KHz) and for the low frequency range (0.25-1.0 KHz). Approximately two-thirds of subjects demonstrated preservation of preoperative thresholds to within 20 dB. Preservation of low frequency thresholds post-implant was shown to correlate moderately with cochleostomy site, being more likely for subjects with a site anterior-inferior to the round window but also possible with inferior locations; weakly with cochleostomy size, being more likely when smaller than 1.2 mm; and also with the use of Healon® as a sealant and lubricant. Preservation of hearing thresholds across up to 4000 Hz was shown to correlate weakly with the use of suction following opening of the endostium and with bone dust contamination, both having a negative effect upon preservation, while no correlation was observed with the preservation of thresholds for low frequencies alone.

The Intensity-Pitch Relation Revisited: Monopolar Versus Bipolar Cochlear Stimulation

from Laryngoscope

Abstract:
Objective/Hypothesis: The very high speech perception scores now being achieved with cochlear implants have led to demands for similar levels of achievement in music perception and perception in noisy environments. One of the crucial factors in these fields is pitch perception. The aim of the present study was to investigate the extent to which pitch perception is influenced by the intensity of the stimulus, through the use of different stimulation modes (monopolar, bipolar) and different electrodes (lateral and perimodiolar).

Study Design: Sixteen postlingually deafened patients with an average implant use of 3.1 years were included in this study. All patients were using a Cochlear (CI24M, CI24R, CI24RE) cochlear implant.

Methods: Subjects were asked to compare the pitch of an intensity-constant reference tone with the pitch of a test tone of varying intensity. The test was repeated for apical, mediocochlear, and basal channel locations, and also for monopolar and bipolar stimulation.

Results: It was found that in monopolar stimulation 87.5% and in bipolar stimulation 85.7% of the patients perceived a clear pitch change with changing intensity of the stimulus (Spearman correlation coefficients r 0.3, respectively). A total of 73.1% of these patients perceived lower pitches with increasing intensity, 26.9% reported the opposite effect. No statistically significant difference in the intensity-pitch correlation could be found between mono- and bipolar stimulation. Neither the mean dynamic range nor the type of electrode used was found to be related to the correlation coefficient.

Conclusion: Although the majority of today’s cochlear implant recipients perform well and the intensity-pitch relation in cochlear implant recipients is still poorly understood, rising demands on speech-coding strategies may soon make a compensation of the pitch shifts desirable. Although the results of our study tend to argue against a peripheral mechanism, the exact origin of this phenomenon remains unclear.

(C) The American Laryngological, Rhinological & Otological

A New Fine Structure Speech Coding Strategy: Speech Perception at a Reduced Number of Channels

from Otology & Neurotology

Abstract:
Objective: One of the most commonly used speech coding strategies for cochlear implants is continuous interleaved sampling (CIS), which codes the envelope information of an acoustic signal. Based on this strategy, MED-EL has recently developed the new fine structure processing (FSP) speech coding strategy, which also transmits subtle pitch and temporal cues. The aim of this study was to investigate the number of active channels necessary for good speech perception with FSP and whether there is an advantage for FSP compared with CIS at a reduced number of channels.

Methods: Ten postlingually deafened patients using MED-EL Pulsar cochlear implants participated in this study. Patients were tested with all 12, 8, 5, 3, and 2 channels with CIS and FSP strategy, resulting in a total of 10 conditions. Performance was tested with numbers, monosyllables, and sentence tests.

Results: Our results showed an improvement in speech perception, with up to 5 channels for numbers and for monosyllables and sentence tests. Statistically significant increases in performance were noted from 3 to 8 channels for numbers, from 3 to 5 channels for monosyllables, and from 5 to 8 channels for sentence tests. No statistical significance was observed whether FSP or CIS was used.

Conclusion: Based on these findings, the number of channels necessary for speech perception with FSP is similar to published results using CIS. There seems to be no advantage for FSP compared with CIS in the conditions of the present experiment.

Cochlear Implant Magnet Displacement During Magnetic Resonance Imaging

from Otology & Neurotology

Abstract:
Objective: Magnet displacement is a rare but possible complication in patients with cochlear implants. We report 1 case in a young child that occurred during magnetic resonance imaging scanning, despite precautionary measures taken by the surgeon and the radiographer.

Study Design: Retrospective case report.

Setting: This case is presented by the ENT Department of Armand Trousseau Paediatrics Hospital, Paris, France.

Patient: An 8-year-old child, implanted with a Freedom Contour Nucleus cochlear implant, was referred for a 1.5-T cerebral magnetic resonance imaging because of a progressive neurologic disorder.

Conclusion: This rare complication underlines the importance of risk information and preventive measures required, even in case of compatible devices, for performing a magnetic resonance imaging examination in patients wearing a cochlear implant with removable magnet.

Deafness in the developing world: the place of cochlear implantation

from the Journal of Laryngology and Otology

Abstract
Introduction: This paper attempts to review changes in the lives of hearing-impaired patients within the developing world, brought about by globalisation and development. The paper also explores limitations to improved care and addresses the collective moral responsibility of developed nations.

Methods: Analysis of literature.

Results: Within developing nations, large populations have emerged with a similar pattern of problems, access to information and aspirations as those living in developed nations. However, marked differences in income have persisted. These trends have resulted in a relative increase in the proportion of the hearing-impaired population in need of cochlear implantation, while at the same time restricting their access to such treatment.

Conclusions: The emergence of global markets and media and a shared sense of destiny amongst the people of this planet should translate into a concerted, worldwide effort to assist the deaf in developing countries. Much more can be done within existing resources and frameworks to improve the quality of these peoples’ lives.

Mandarin Chinese tone identification in cochlear implants: Predictions from acoustic models

from Hearing Research

It has been established that current cochlear implants do not supply adequate spectral information for perception of tonal languages. Comprehension of a tonal language, such as Mandarin Chinese, requires recognition of lexical tones. New strategies of cochlear stimulation such as variable stimulation rate and current steering may provide the means of delivering more spectral information and thus may provide the auditory fine-structure required for tone recognition. Several cochlear implant signal processing strategies are examined in this study, the continuous interleaved sampling (CIS) algorithm, the frequency amplitude modulation encoding (FAME) algorithm, and the multiple carrier frequency algorithm (MCFA). These strategies provide different types and amounts of spectral information. Pattern recognition techniques can be applied to data from Mandarin Chinese tone recognition tasks using acoustic models as a means of testing the abilities of these algorithms to transmit the changes in fundamental frequency indicative of the four lexical tones. The ability of processed Mandarin Chinese tones to be correctly classified may predict trends in the effectiveness of different signal processing algorithms in cochlear implants. The proposed techniques can predict trends in performance of the signal processing techniques in quiet conditions but fail to do so in noise.

Reading abilities after cochlear implantation: The effect of age at implantation on outcomes at 5 and 7 years after implantation

from the International Journal of Pediatric Otorhinolaryngology

Objectives
The reading skills of deaf children have typically been delayed and this delay has been found to increase with age. This study explored the reading ability of a large group of children who had received cochlear implants 7 years earlier and investigated the relationship between reading ability and age at implantation.

Methods
The reading ages of 105 children, with age at implantation less than 7 years and onset of deafness below the age of three, were assessed 5 and 7 years after implantation using the Edinburgh reading test. Net reading age was calculated by using the difference between chronological age and reading age. Non-verbal intelligence was measured for a subset of 71 children, using Raven’s coloured progressive matrices. Further investigation of this subset looked at the association of nonverbal intelligence, age at implantation and reading ability.

Results
There was a strong negative correlation at both 5 and 7 years after implant between net reading score and age at implantation. In the subset of 71 children who had an IQ score within normal range, those implanted at or before 42 months had age-appropriate reading both 5 and 7 years post-implant. This was not the case for children implanted after 42 months. Reading progress at the two post-implant assessment intervals were found to be highly related.

Conclusions
Age at implantation was a significant factor in the development of reading skills in this group. In children implanted below the age of 42 months, reading progress was in line with chronological age, which has not been the case previously with profoundly deaf children. With earlier implantation more common in present groups, and improved technology, there is every reason to be optimistic about the influence of cochlear implantation on the development of reading skills in deaf children.

Long-term Trajectories of the Development of Speech Sound Production in Pediatric CochlearImplant Recipients

from the Journal of Speech, Language, and Hearing Research

Purpose: This study characterized the development of speech sound production in prelingually deaf children with a minimum of eight years of cochlear implant (CI) experience.

Method: Twenty-seven pediatric CI recipients’ spontaneous speech samples from annual evaluation sessions were phonemically transcribed. Accuracy for these speech samples was evaluated in piecewise regression models.

Results: As a group, pediatric CI recipients showed steady improvement in speech sound production following implantation, but the improvement rate declined after six years of device experience. Piecewise regression models indicated that the slope estimating the participants’ improvement rate was statistically greater than zero during the first six years post-implantation, but not after six years. The group of pediatric CI recipients’ accuracy of speech sound production after four years of device experience reasonably predicts their speech sound production after five to 10 years of device experience.

Conclusions: The development of speech sound production in prelingually deaf children stabilizes after six years of device experience, and typically approaches a plateau by eight years of device use. Early growth in speech before four years of device experience did not predict later rates of growth or levels of achievement. However, good predictions could be made after four years of device use.

Effects of stimulus manipulation on electrophysiological responses in pediatric cochlear implant users. Part I: Duration effects

from Hearing Research

Discrepancies between electrophysiological and behavioral thresholds in cochlear implant users might be due to differences in stimuli including the duration and rate of the electrical pulse train. In the present study, we asked: Is there an effect of stimulus duration on electrophysiological responses of the auditory brainstem and thalamo-cortex and behavioral thresholds? In 5 pediatric cochlear implant users, behavioral thresholds in response to electrical pulse trains at 500 pulses per second (pps) were significantly lower for 40ms than 2ms duration pulse trains. Clear electrically evoked auditory brainstem responses (EABR) and electrically evoked middle latency responses (EMLR) were evoked by single electrical pulses and 2, 6, and 10ms pulse trains (500pps) in 5 children. There was a linear decrease in the inter-wave latency between the eV of the EABR and the Na of the EMLR as duration increased. No significant effect of duration was found on eV latency relative to the last pulse in the train or Na latency relative to the onset of the stimuli. Behavioral threshold data is consistent with temporal integration of auditory activity. Electrophysiological data indicates that: (a) recognizable EABR and EMLRs can be recorded in response to electrical pulse trains of up to 10ms; and (b) pulse train stimuli have unique effects on the auditory brainstem compared to thalamo-cortical areas.

Effects of stimulus manipulation on electrophysiological responses of pediatric cochlear implant users. Part II: Rate effects

from Hearing Research

Electrophysiological thresholds do not accurately predict behavioral thresholds in pediatric cochlear implant users possibly due to differences in rate and duration of pulse presentation. We asked: (1) is there an effect of rate of stimulus presentation on the electrophysiological responses of the auditory brainstem and thalamo-cortex? and (2) can the relationship between electrophysiological and behavioral thresholds be improved by using the same rate of pulse presentation? Behavioral and electrophysiological (EABR and EMLR) responses were elicited for 14 children to single electrical pulses and pulse trains of 2ms ranging in rate from 500 to 3600pulsespersecond(pps). Low rate (500pps) pulse trains resulted in an increase in EABR wave eIII amplitude and a decrease in wave eV amplitude. Further rate increases resulted in even smaller EABR wave amplitudes. Neither EMLR amplitudes nor latencies of the EABR or EMLR were affected by increases in rate. Behavioral thresholds decreased with increasing rate, however, there was no associated reduction in electrophysiological thresholds. Correlation between behavioral and electrophysiological thresholds did not improve by using the same rate of electrical pulse stimulation. Results suggest: (1) higher rates of electrical pulse presentation increase the potential for neural adaptation in the auditory brainstem and (2) using the same rate of electrical pulse presentation does not improve the ability of EABR and EMLR thresholds to predict behavioral thresholds.

Free field frequency discrimination abilities of cochlear implant users

from Hearing Research

Poor music perception abilities of cochlear implant users may be attributed to limited pitch resolution afforded by the implant system. We investigated (i) what the typical frequency discrimination thresholds of cochlear implant users would be in free field listening conditions and (ii) whether frequency discrimination behaviour would be influenced by the position of the reference frequency relative to the frequency response of filters selected from the user’s map. Frequency discrimination thresholds were determined according to an adaptive two-alternative forced choice (2AFC) method, using pure tones delivered in free field conditions. Results showed that finer frequency resolution than previously thought could be available to cochlear implant users. Results are interpreted in terms of intermediate pitch percepts possibly created by near-simultaneous activation of adjacent electrodes, resulting in overlapping neural populations to be stimulated. The findings may contribute to strategies aiming to improve music perception abilities of cochlear implant users.

Supporting Children with Cochlear Implant in Mainstream schools for LSAs

from the National Library for Health

Supporting Children with Cochlear Implant in Mainstream schools for LSAsHosted by Wandsworth HI Service and supported by NDCS
This course takes place at:

Barnes Room, Education Suite, 2nd Floor
Queen Mary’s Hospital
Roehampton, SW15 5PN.

Please register as usual through the link below

The day will include:

Cochlear Implants how do they work?
Update on expectations, outcomes and current research
Issues of management with C.I pupils in the classroom
Management of technology in the classroom environment
Consider the role of the LSA
For further information contact:

The Ear Foundation
Marjorie Sherman House
83 Sherwin Road
Lenton
NOTTINGHAM
NG7 2FB
UK

Tel : 0115 942 1985
Fax : 0115 924 9054

http://www.earfoundation.org.uk/bookings/?id=402
Where:London
When:23 Sep 2008 10:00 - 16:00

Using Early Language Outcomes to Predict Later Language Ability in Children with Cochlear Implants

from Audiology & Neuro-Otology

The increased access to sound that cochlear implants have provided to profoundly deaf children has allowed them to develop English speech and language skills more successfully than using hearing aids alone. The purpose of this study was to determine how well early postimplant language skills were able to predict later language ability. Thirty children who received a cochlear implant between the years 1991 and 2000 were study participants. The Reynell Developmental Language Scales (RDLS) and the Clinical Evaluation of Language Fundamentals (CELF) were used as language measures. Results revealed that early receptive language skills as measured using the RDLS were good predictors of later core language ability assessed by the CELF. Alternatively, early expressive language skills were not found to be good predictors of later language performance. The age at which a child received an implant was found to have a significant impact on the early language measures, but not the later language measure, or on the ability of the RDLS to predict performance on the CELF measure.

New York Resident, Expected To Regain Hearing in Both Ears for the First Time in Over 40 Years

from Newswise.com

Cochlear, the world’s leader in advanced hearing technologies will reach a landmark milestone on Tuesday, August 12 when 72-year-old, New York resident, Susan Grossman became the 120,000 individual has her bilateral Nucleus® Freedom cochlear implant (a small electronic device that can provide a sense of sound to someone who is deaf) activated. Susan began to loose her hearing, in her right ear, in her 30s, and her hearing loss steadily grew worse over time, eventually leaving her almost deaf on both ears.

Mother outraged after NHS only agrees to fix hearing in one ear of her deaf daughter

from MailOnline

An angry mother and local GP has accused health managers of operating a postcode lottery because they will fund only one cochlear implant for her profoundly deaf child.

Relationships among objective measures and speech perception in adult users of the HiResolution Bionic Ear

from Cochlear Implants Internations

The purpose of this study was to describe speech recognition performance for subjects using electrically evoked stapedial reflex thresholds (eSRT) based on programs with the HiResolution Bionic Ear system. A secondary goal was to evaluate the relationship of the electrically evoked compound action potentials (eCAP) as measured with neural response imaging (NRI) relative to the subjects’ most comfortable stimulation levels (M levels). M levels, eSRT and eCAP thresholds were measured in 19 postlinguistically deafened adults using either a CII or HiRes 90K cochlear implant. The results showed that eSRTs could be measured easily in a majority of subjects, whereas eCAPS were measured in all subjects. There were close agreements between eSRTs and M levels in the subjects’ behaviorally based programs. In contrast, the correspondence between M levels and eCAP thresholds was not as strong. New programs were created with M levels based on the eSRTs for 11 subjects. Programs created using eSRTs as a guide for setting levels yielded better speech recognition than programs using conventional behavioural measures of M levels. These data indicate that individuals can obtain strong benefits from cochlear implants using programs with stimulation levels based on objective measures. Copyright © 2008 John Wiley & Sons, Ltd.

Implanting outside the guidelines: a case study

from the Journal of the American Academy of Audiology

An 81-year-old female was referred for cochlear implantation due to difficulty communicating in her daily activities despite the use of appropriate amplification. The poorer ear was unable to tolerate amplification for the past 15 years. The open-set sentence-recognition test score in quiet in her “good” ear was 85 percent correct, indicating that the patient was not a traditional cochlear implant candidate. However, the sentence-recognition score in noise at +10 dB signal-to-noise ratio was 0 percent, demonstrating a significant breakdown in the patient’s speech understanding in more difficult listening situations. This speech-in-noise score appeared to correlate with the patient’s reported communication difficulties as well as with the communicative breakdowns that were observed clinically. The patient underwent cochlear implantation in the better ear. Cochlear implantation in this nontraditional patient provided objective and subjective benefit over hearing aid use.

Multivariate predictors of music perception and appraisal by adult cochlear implant users

from the Journal of the American Academy of Audiology

The research examined whether performance by adult cochlear implant recipients on a variety of recognition and appraisal tests derived from real-world music could be predicted from technological, demographic, and life experience variables, as well as speech recognition scores. A representative sample of 209 adults implanted between 1985 and 2006 participated. Using multiple linear regression models and generalized linear mixed models, sets of optimal predictor variables were selected that effectively predicted performance on a test battery that assessed different aspects of music listening. These analyses established the importance of distinguishing between the accuracy of music perception and the appraisal of musical stimuli when using music listening as an index of implant success. Importantly, neither device type nor processing strategy predicted music perception or music appraisal. Speech recognition performance was not a strong predictor of music perception, and primarily predicted music perception when the test stimuli included lyrics. Additionally, limitations in the utility of speech perception in predicting musical perception and appraisal underscore the utility of music perception as an alternative outcome measure for evaluating implant outcomes. Music listening background, residual hearing (i.e., hearing aid use), cognitive factors, and some demographic factors predicted several indices of perceptual accuracy or appraisal of music.