Quantitative Analysis of Electrically Evoked Auditory Brainstem Responses in Implanted Children With Auditory Neuropathy/Dyssynchrony

from Otology & Neurotology

Objective: Cochlear implantation is a common treatment approach for children with auditory neuropathy/dyssynchrony (AN/AD) who do not benefit from hearing aids. The auditory brainstem response (ABR) is a measure of neural synchrony along the auditory pathway up through the brainstem. By definition, acoustically evoked ABR is absent in AN/AD, however, ABR can be elicited by electrical stimulation through the cochlear implant (electrically evoked ABR [EABR]). Reports of EABR with AN/AD to date have been primarily descriptive in nature. The objective of this study was to quantify EABR wave V measures in implanted children with and without AN/AD.

Study Design: Retrospective analysis of EABR waveforms from March 2000 through February 2005.

Setting: Comprehensive Cochlear Implant Program/Tertiary Referral Center.

Patients: Pediatric cochlear implant users of two etiologic groups: congenital AN/AD (n = 5) and other congenital profound sensorineural hearing loss (n = 27).

Intervention: Diagnostic.

Main Outcome Measures: Intraoperative EABR wave V threshold, suprathreshold amplitude, and latency measures were compared between groups.

Results: The EABR threshold and suprathreshold amplitude measures across the population were variable regardless of etiology. With some exceptions, a trend was observed for the AN/AD group that included average or below-average thresholds and below-average suprathreshold response amplitudes.

Conclusion: Cochlear implantation can provide synchronous neural responses to auditory stimulation in AN/AD, as previously known. The quantification of EABR measures in this study indicates that subjects with AN/AD have sufficient neural sensitivity to electrical stimulation, however, they may experience less robust neural responses at suprathreshold levels. Given the heterogeneity of potential causes of AN/AD, however, caution needs to be applied when grouping this population for analyses.

Reimplantation of Hybrid Cochlear Implant Users With a Full-Length Electrode After Loss of Residual Hearing

from Otology & Neurotology

Objective: To assess word recognition and pitch-scaling abilities of cochlear implant users first implanted with a Nucleus 10-mm Hybrid electrode array and then reimplanted with a full length Nucleus Freedom array after loss of residual hearing.

Background: Although electroacoustic stimulation is a promising treatment for patients with residual low-frequency hearing,a small subset of them lose that residual hearing. It is not clear whether these patients would be better served by leaving in the 10-mm array and providing electric stimulation through it, or by replacing it with a standard full-length array.

Methods: Word recognition and pitch-scaling abilities were measured in 2 users of hybrid cochlear implants who lost their residual hearing in the implanted ear after a few months. Tests were repeated over several months, first with a 10-mm array, and after, these patients were reimplanted with a full array. The word recognition task consisted of 2 50-word consonant nucleus consonant (CNC) lists. In the pitch-scaling task, 6 electrodes were stimulated in pseudorandom order, and patients assigned a pitch value to the sensation elicited by each electrode.

Results: Shortly after reimplantation with the full electrode array, speech understanding was much better than with the 10-mm array. Patients improved their ability to perform the pitch-scaling task over time with the full array, although their performance on that task was variable, and the improvements were often small.

Conclusion: 1) Short electrode arrays may help preserve residual hearing but may also provide less benefit than traditional cochlear implants for some patients. 2) Pitch percepts in response to electric stimulation may be modified by experience.

Results from a Psychoacoustic Model-Based Strategy for the Nucleus-24 and Freedom Cochlear Implants

from Otology & Neurotology

Objective: In normal-hearing listeners acoustic masking occurs depending on frequency, amplitude, and energy of specific signals. If the selection of stimulated channels in cochlear implant systems was based on psychoacoustic masking models, the bandwidth of the electrode/nerve interface could be used more effectively by concentrating on relevant signal components and neglecting those that are usually not perceived by normal hearing listeners. Subsequently, a new strategy called PACE (Psychoacoustic Advanced Combination Encoder) has been developed which uses a psychoacoustic model for the channel selection instead of the simple maxima selection algorithm of the ACE strategy.

Study Design: Only subjects having at least 2 years experience with the ACE strategy were included. A counterbalanced cross-over design was used to compare the new speech coding strategy with the ACE strategy.

Setting: The investigation was a prospective, within-subject, repeated-measures experiment.

Patients: The study group consisted of 10 postlingually deafened adult subjects.

Interventions: The following programs were evaluated: (1) ACE with 8 maxima selected; (2) PACE with 8 channels selected; and (3) PACE with 4 channels selected.

Main Outcome Measures: Speech perception tests in quiet and noise, Quality Assessment Questionnaire.

Results: Results indicate a trend towards better performance with PACE. Scores in the Freiburg monosyllabic word test increased by 8% while the SNR50 in the Oldenburger sentence test improved significantly by 1.3 dB.

Conclusion: The use of psychoacoustic masking models in speech coding strategies has the potential to improve speech perception performance in cochlear implant subjects.

Revision Cochlear Implant Surgery in Children

from Otology & Neurotology

Objective: To determine the incidence of revision cochlear implant (CI) surgery in children and the indications for revision surgery and to examine the pattern of events that lead to revision CI surgery.

Study Design: Retrospective case review.

Setting: Two tertiary pediatric CI centers.

Patients: Pediatric CI patients who underwent revision surgery related to their CI.

Main Outcome Measures: Reasons for revision, surgical outcomes, complications, performance, and device analyses were sought.

Results: Nine hundred fifty-two pediatric CI operations were performed between 1991 and 2005. Ninety-three patients underwent 107 (11.2%) revision operations. Hard device failure occurred in 46% (n = 49); soft failure occurred in 15% (n = 16); medical/surgical causes were responsible for 37% (n = 40); and magnet dislodgement requiring revision surgery occurred in 2% (n = 2). Head trauma was associated with 41% of the hard failure cases (n = 20). Device analyses revealed identifiable abnormalities in most of both hard and soft failure cases. In most patients, auditory performance equaled or surpassed the best preoperative performance by 6 to 12 months after revision.

Conclusion: Revision CI surgery is common among pediatric CI recipients. Hard failure is the most common reason for undertaking revision surgery, and this mode of failure is frequently associated with preceding head trauma. Patients and parents should be counseled that performance is expected to equal or surpass the child’s best level of performance before revision surgery, although this may take some time, and exceptions do exist.

Rotating Computed Tomographic Movie for Evaluating Partially Ossified Cochlea

from Otology & Neurotology

Objective: To describe our newly devised method of viewing intracochlear ossification for the purpose of minimizing bone drilling during cochlear implantation for partially ossified cochleas and to evaluate its usefulness.

Study Design: Descriptive study that compares 1) conventional computed tomographic (CT) films with the newly devised CT movie and 2) preoperative evaluation using the CT movie with the findings during surgery.

Setting: University Hospital

Patients: Four cochlear implantees with partial ossification of cochlea due to meningitis.

Intervention: Diagnostic.

Main Outcome Measures: Reconstruction of high-resolution CT images of the temporal bone was performed using a multiplanar reformat software. By rotating the cochlear cross plane from the round window niche in the direction of the inferior segment by 5 degrees, 72 images were obtained for 360-degree rotation, which were converted to a movie using QuickTime Pro software. The preoperative evaluation and intraoperative findings were compared.

Results: The advantage of CT movie over sequential CT films was facility in understanding the 3-dimensional space in the cochlea. Evaluation of the extent of the ossified region on CT movie corresponded to the intraoperative findings in all 4 patients. In 1 patient, the CT movie corrected an erroneous evaluation based on conventional CT films. However, additional drilling over the extent of ossification was necessitated in another patient because of scar tissue development.

Conclusion: Computed tomographic movie is considered an innovative new method for preoperative evaluation of ossified cochleas and is able to reduce human errors. However, additional drilling beyond ossified part can become necessary during surgery.

Speech Perception in Children With Auditory Neuropathy/Dyssynchrony Managed With Either Hearing Aids or Cochlear Implants

from Otology & Neurotology

Objective: To evaluate speech perception skills in children with auditory neuropathy (AN)/auditory dyssynchrony (AD)-type hearing loss managed with either hearing aids or cochlear implants.

Study Design: Prospective data collection in 3 subject groups: AN/AD children fitted with bilateral amplification, AN/AD children fitted with cochlear implant (in 1 or both ears), and a matched control group of implanted children with sensorineural hearing loss.

Main Outcome Measure: Open-set monosyllabic words (consonant-nucleus-consonant).

Results: Of the 10 implanted AN/AD children, 9 demonstrated significant speech discrimination (consonant-nucleus-consonant phoneme score >=55%). Similar results were obtained for the aided AN/AD group. Findings for both AN/AD subject groups were poorer than those of the implanted sensorineural cohort.

Conclusion: Cochlear implantation can offer useful hearing in subjects with AN/AD-type hearing loss. However, expectations for this group may need to be lower than for patients with peripheral (cochlear) loss.

The Cost and Analysis of Nonuse of Cochlear Implants

from Otology & Neurotology

Objective: Analysis of the cost implications and reasons for nonuse of cochlear implants in an established cochlear implant unit.

Study Design: Clinical data were analyzed retrospectively to construct a table of cochlear implant use over time to identify nonuse and to suggest the reasons for this.

Setting: Yorkshire Cochlear Implant Service is a tertiary referral center.

Patients: Three hundred forty consecutively implanted patients from 1990 to 2005.

Main Outcome Measures: Life table analysis showed that most children used their implant (p = 0.7 during 11 yr). However, 11 of 155 children and 2 of 185 adults became nonusers during the period of study. The 11 children stopped because of age at implant, educational placement, and family support. Two adults stopped because of psychological issues and inability to adapt to the signal. Surgical and implant costs have initial impact, with subsequent years’ costs reflecting programming issues and maintenance. When considering nonuse, there are 2 effects: first, no more costs are incurred, and second, no more years of use are accumulated. Thus, nonuse reduces both costs and years. Costs of gaining a year of use as a function of time showed that there was little financial impact from the 11 children nonusers. As a ratio of “no nonuse” and observed “nonuse” in children, the ratio is 1.07 by 13 years of implantation (7%). The adult group was too few to analyze.

Conclusion: The nonuse added 7% to the average cost. Retrospective audit identifies that patient selection by a multidisciplinary team is crucial to reducing nonuse.

Tracking Development of Speech Recognition: Longitudinal Data From Hierarchical Assessments in the Childhood Development After Cochlear Implantation Study

from Otology & Neurotology

Objective: To develop a speech recognition index that summarizes data collected through an array of age-appropriate hierarchical speech recognition tests in a longitudinal study.

Study Design: Prospective cohort.

Setting: Six tertiary referral centers in the Childhood Development after Cochlear Implantation (CDaCI) Study.

Patients: One hundred eighty-eight children implanted at age 5 years or younger and 97 age-comparable normal-hearing controls.

Intervention: Cochlear implantation.

Main Outcome Measures: Outcome measures were the following: Infant-Toddler Meaningful Auditory Integration Scale, Meaningful Auditory Integration Scale, Early Speech Perception Test, Pediatric Speech Intelligibility Test, Multisyllabic Lexical Neighborhood Test, Lexical Neighborhood Test, and Hearing in Noise Test, obtained before implantation and at 6, 12, 18, and 24 months postimplant.

Results: A speech recognition cumulative index, speech recognition index in quiet (SRI-Q), was created to combine information from tests administered in quiet. This index allows simultaneous display of data from all tests in the speech recognition hierarchy and is sensitive to improvements in performance over time as a function of age. SRI-Q also provides a composite of performance on multiple tests, allowing both the tracking of “growth curve” in speech recognition across a wide age range over an extended follow-up period and the comparison of normal-hearing and implanted children on multiple measures. The data range for individual tests is also preserved for ease of interpretation.

Conclusion: SRI-Q allows tracking of global development of speech recognition over time as children progress through a hierarchy of speech perception measures and complements the more detailed assessments obtained from individual tests within the hierarchy.

Using the Observer-Based Psychophysical Procedure to Assess Localization Acuity in Toddlers Who Use Bilateral Cochlear Implants

from Otology & Neurotology

Hypothesis: Localization acuity will emerge in deaf children who receive bilateral cochlear implants (BI-CIs) before the age of 3 years but not in age-matched children who use a single device.

Background: There is a growing clinical trend in which infants with severe-to-profound sensorineural hearing loss are receiving BI-CIs by 3 years. Although there is general agreement that better communicative and educational outcomes are achieved when the first implant is provided at a young age, there are few behavioral data showing the functional benefits of providing infants with BI-CIs. One potential benefit of BI-CIs is improved localization acuity, which develops within the first few years of life.

Methods: Two groups of children with chronological ages ranging from 26 to 36 months participated: 1) children with normal hearing (n = and 2) children with severe-to-profound sensorineural hearing loss (n = 18). Of the children who are deaf, 10 used BI-CIs, and 8 used unilateral cochlear implants. Localization acuity was measured with a single interval 2-alternative-forced choice right/left discrimination task, and minimum audible angles were computed at a performance level of 80% correct. Behavioral data were collected using the observer-based psychophysical procedure.

Results: Preliminary results show that the observer-based psychophysical procedure is a feasible method to measure localization acuity in children with normal hearing and in deaf children with cochlear implants and that localization acuity is emerging in toddlers with BI-CIs but not yet in toddlers with unilateral cochlear implants.

Conclusion: These data are among the first to show localization acuity in young children who use BI-CIs.

Variance of Angular Insertion Depths in Free-Fitting and Perimodiolar Cochlear Implant Electrodes

from Otology & Neurotology

Objective: To assess the variance in cochlear implant electrode insertion depth in degrees around the modiolus (angular insertion depth) in free-fitting and perimodiolar electrode arrays.

Materials and Methods: Twenty-eight fresh human temporal bones were implanted with free-fitting cochlear implant electrodes, and 18 bones were implanted using perimodiolar electrode arrays. Specimens were embedded, and 2-dimensional radiographs were obtained to assess angular insertion depths. Histologic serial sections of undecalcified bones were then evaluated to analyze intracochlear electrode positions. Finally, linear surgical insertion depths (in millimeters) were correlated with angular insertion depth (degrees around the modiolus).

Results: A moderate variance of angular insertion depth was documented for both free-fitting and perimodiolar electrode arrays. Full insertions into the scala tympani ranged from 540 to 630 degrees with free-fitting arrays and from 270 to 375 degrees with perimodiolar electrodes. In free-fitting devices, a linear relationship between linear (in millimeters) and angular (degrees) insertion depths was observed. Insertions into scala vestibuli were observed in 9 of 28 and 5 of 18 of the specimens for free-fitting and perimodiolar electrodes, respectively. Additionally, scala vestibuli insertions showed greater angular insertion depths when compared with scala tympani implantations.

Conclusion: Variances in angular insertion depths seem to be moderate and similar in free-fitting and perimodiolar electrode arrays. Scala vestibuli insertions showed greater angular insertion depths than comparable insertions into the scala tympani. In perimodiolar electrodes, angular insertion depths equal or greater than 390 degrees suggested scala vestibuli placement.

A Longitudinal Study of Speech Production in Swedish Children With Unilateral Cleft Lip and Palate and Two-stage Palatal Repair

from the Cleft Palate-Craniofacial Journal

Objective:To describe speech production longitudinally in a group of children with unilateral cleft lip and palate (UCLP).

Participants:Twenty consecutive children with UCLP and nine age-matched children without clefts in a comparison group.

Intervention: A two-stage palatal repair procedure with soft palate closure at 6 months and hard palate repair at 3 to 4 years.

Main Outcome Measures:Percent correct consonants (PCC), percent correct places (PCP), and percent correct manners (PCM) at 3, 5, and 7 years of age. Cleft speech errors at the same ages. Previously collected data on number of consonant tokens, consonant types, frequency of occurrence of places and manners of articulation at 18 months.

Results:PCC and PCP were significantly lower in the UCLP group than in the comparison group at all ages. Number of consonant types and frequency of occurrence of dental plosives at 18 months correlated significantly with PCC at age 3. A high frequency of velar plosives at 18 months correlated significantly with a high prevalence of retracted oral articulation (dental/alveolar to palatal or velar) at both 3 and 5 years of age.

Conclusions:The UCLP group performed worse than the comparison group at all ages. A high occurrence of dental plosives as well as a high number of consonant types in babbling and first words seem to be good indicators for better consonant production in later speech. The same prevalence of retracted oral articulation as in previous studies is attributed to the surgical technique.

Early Intervention for Speech Impairment in Children With Cleft Palate

from the Cleft Palate-Craniofacial Journal

Objective:This study explored the effectiveness of a parent-implemented, focused stimulation program on the speech characteristics of children younger than 3 years with cleft lip and palate. The research questions included the following: (1) Can parents be trained to deliver an early intervention (EI) program for children with cleft palate? (2) Does a parent-implemented EI program result in positive changes in speech characteristics?

Participants:Ten mother-child pairs in which the child had cleft lip and palate (CLP) and 10 mother-child pairs in which the child did not have a cleft (NCLP). The children ranged in age from 14 to 36 months of age and were matched between the CLP and the NCLP groups for vocabulary size, age, and socioeconomic status.

Main Outcome Measures:Group differences (CLP and the NCLP) for preintervention and postintervention language and speech measures were compared.

Results:The results of this study showed that the mothers could be trained to deliver the intervention reliably. Furthermore, the results indicated that the intervention resulted in increased sound inventories, increased speech accuracy, and reduced use of glottal stops for the children with clefts.

Conclusions:While the intervention resulted in speech gains for the children with clefts, speech measures did not exceed those made by the children without clefts. The results of the study have implications for service delivery models where the services of speech-language pathologists are limited.

Fiberoptic endoscopic evaluation of swallowing with simultaneous tensilon application in diagnosis and therapy of myasthenia gravis

from the Journal of Neurology

Background Dysphagia is a common symptom in myasthenia gravis (MG). Clinical examination alone fails to detect and grade myasthenic dysphagia sufficiently. For a more precise examination of swallowing function in myasthenia gravis additional technical tools are necessary.
Objective To investigate the diagnostic and therapeutic impact of fiberoptic endoscopic evaluation of swallowing with simultaneous Tensilon application (FEES-Tensilon Test) in myasthenia gravis.
Methods FEES-Tensilon Test was performed following a standardized protocol. Four severely affected patients with dysphagia as their leading symptom were examined. Dysphagia was characterized by five salient endoscopic findings: leakage, delayed swallowing reflex, penetration, aspiration and residues. If a normalisation or at least an improvement of swallowing function occurred shortly after Tensilon administration the FEES-Tensilon Test was rated as being positive.
Results In three patients the FEES-Tensilon Test successfully detected MG-related dysphagia. In one patient with dysphagia caused by oculopharyngeal muscular dystrophy the FEES-Tensilon Test was truly negative. Beside an early diagnosis of MG-related dysphagia, the FEES-Tensilon Test was useful in the differentiation between myasthenic and cholinergic crisis and in guiding treatment decisions. In all patients the FEES-Tensilon Test was superior to clinical evaluation of dysphagia. No severe side effect occurred while performing the FEES-Tensilon Test.
Conclusion The FEES-Tensilon Test is a suitable tool in the diagnosis and therapy of myasthenia gravis with pharyngeal muscles weakness.

Universal Parameters for Reporting Speech Outcomes in Individuals With Cleft Palate

from the Cleft Palate-Craniofacial Journal

Objective:To achieve consistency and uniformity in reporting speech outcomes in individuals born with cleft palate with or without cleft lip using perceptual parameters that characterize their speech production behavior regardless of the language or languages spoken.

Design:A working group of six individuals experienced in speech and cleft palate was formed to develop a system of universal parameters for reporting speech outcomes in individuals born with cleft palate. The system was adopted in conjunction with a workshop held in Washington, D.C., that was devoted to developing the universal system. The system, which was refined further following the workshop, involves a three-stage plan consisting of (1) evaluation, (2) mapping, and (3) reporting. The current report focuses primarily on the third stage, reporting speech outcomes.

Results:A set of five universal speech parameters has been devised for the reporting stage. These consist of (1) hypernasality, (2) hyponasality, (3) audible nasal air emission and/or nasal turbulence, (4) consonant production errors, and (5) voice disorder. Also included are speech understandability and speech acceptability, global parameters that can be reported for any type of speech disorder. The parameters are described in detail, and guidelines for speech-sampling content and scoring procedures in relation to the parameters are presented.

Conclusion:A plan has been developed to document speech outcomes in individuals with cleft palate, regardless of the spoken language, using a set of five universal reporting parameters and two global speech parameters.

In Cairo the noise pollution can be a killer

fromYahoo! Health

From blaring car horns to wedding parties, rising noise pollution in the 24-hour metropolis of Cairo has reached alarming levels, leading to hearing problems, irritability and even death.