Degree Of Residual Hearing Research Articles

Communication Development Practice of Sound and Rhythm Perception at SLB YRTRW Surakarta

The ability to detect sounds in deaf children often experiences obstacles, due to obstacles to the auditory senses. To improve the ability to detect sounds in deaf children, a sound and rhythm perception communication development (PKPBI) learning program is needed. This research aims to describe the procedures, methods, and tools used in PKPBI learning, as well as the challenges faced by teachers in implementing the learning. The subjects in this study were PKPBI subject teachers and four grade X students at SLB YRTRW Surakarta. This research used qualitative methods in the form of semi-structured interviews and observations. The results showed that the implementation of PKPBI learning at each stage has different procedures, methods, and tools. The challenges experienced at these four stages include the low level of children's attention, the degree of residual hearing that children have, and inadequate facilities and infrastructure.

Contralateral hearing aid use in adult cochlear implant recipients: retrospective analysis of auditory outcomes

Objective To investigate retrospectively the frequency of usage of bimodal stimulation among cochlear implant (CI) users, as well its clinical benefit relative to unilateral use. Design All subjects had been monitored with the clinical Minimal Outcome Measurements test battery. Study samples 103 adults with bilateral postlingual profound sensorineural hearing loss and unilateral CI use were extracted from the local database. These were divided into two groups: those who only used a CI and those who used bimodal stimulation. Results The preoperative contralateral residual hearing in the bimodal group was significantly better than that of the CI-only group. In both groups, speech perception in quiet and in noise improved after CI, with no significant difference between postoperative unimodal conditions. For the bimodal group, an additional significant improvement was found for the bimodal condition compared to the unimodal. Conclusion Given the observed auditory benefit of bimodal stimulation in comparison to unimodal stimulation and given the finding that degree of residual hearing is not correlated with bimodal benefits, it is recommended to encourage CI recipients to continue contralateral HA use after CI. As a result of expanding CI criteria worldwide, the population of bimodal users is expected to grow in the near future.

Comparison of speech recognition in cochlear implant patients with and without residual hearing: A review of indications

Objective This study evaluated existing guidelines for cochlear implantation (CI) according to the residual hearing of the patient. Speech recognition performance of adults implanted according to their degree of residual hearing was retrospectively evaluated. Methods Speech recognition results of 174 adult cochlear implant recipients were analyzed. All participants had pure tone thresholds of >75 dB at 2 and 4 kHz and were divided into three groups based on differing levels of low-frequency residual hearing. Results Findings indicate that CI was of benefit for all patients with bilateral severe hearing loss and patients with nonfunctional residual hearing both in quiet and noisy conditions. Patients with residual low-frequency hearing could benefit from combined electro-acoustic stimulation compared to CI alone or to hearing aids alone preoperatively. The speech recognition performance of all CI recipients with different levels of residual hearing in the low frequencies was similar except that superior performance was observed in the group using electro-acoustic stimulation compared to electrical stimulation alone. Discussion and conclusions Study results demonstrate the success of CI in accordance with current guidelines and also support expanding implantation guidelines to include patients who have severe-to-profound high-frequency sensorineural hearing loss and usable residual low frequency hearing.

"Product" Versus "Process" Measures in Assessing Speech Recognition Outcomes in Adults With Cochlear Implants.

1) When controlling for age in postlingual adult cochlear implant (CI) users, information-processing functions, as assessed using "process" measures of working memory capacity, inhibitory control, information-processing speed, and fluid reasoning, will predict traditional "product" outcome measures of speech recognition. 2) Demographic/audiologic factors, particularly duration of deafness, duration of CI use, degree of residual hearing, and socioeconomic status, will impact performance on underlying information-processing functions, as assessed using process measures. Clinicians and researchers rely heavily on endpoint product measures of accuracy in speech recognition to gauge patient outcomes postoperatively. However, these measures are primarily descriptive and were not designed to assess the underlying core information-processing operations that are used during speech recognition. In contrast, process measures reflect the integrity of elementary core subprocesses that are operative during behavioral tests using complex speech signals. Forty-two experienced adult CI users were tested using three product measures of speech recognition, along with four process measures of working memory capacity, inhibitory control, speed of lexical/phonological access, and nonverbal fluid reasoning. Demographic and audiologic factors were also assessed. Scores on product measures were associated with core process measures of speed of lexical/phonological access and nonverbal fluid reasoning. After controlling for participant age, demographic and audiologic factors did not correlate with process measure scores. Findings provide support for the important foundational roles of information processing operations in speech recognition outcomes of postlingually deaf patients who have received CIs.

Investigation of the effect of cochlear implant electrode length on speech comprehension in quiet and noise compared with the results with users of electro-acoustic-stimulation, a retrospective analysis.

ObjectivesThis investigation evaluated the effect of cochlear implant (CI) electrode length on speech comprehension in quiet and noise and compare the results with those of EAS users.Methodes91 adults with some degree of residual hearing were implanted with a FLEX20, FLEX24, or FLEX28 electrode. Some subjects were postoperative electric-acoustic-stimulation (EAS) users; the other subjects were in the groups of electric stimulation-only (ES-only).Speech perception was tested in quiet and noise at 3 and 6 months of ES or EAS use. Speech comprehension results were analyzed and correlated to electrode length.ResultsWhile the FLEX20 ES and FLEX24 ES groups were still in their learning phase between the 3 to 6 months interval, the FLEX28 ES group was already reaching a performance plateau at the three months appointment yielding remarkably high test scores. EAS subjects using FLEX20 or FLEX24 electrodes outscored ES-only subjects with the same short electrodes on all 3 tests at each interval, reaching significance with FLEX20 ES and FLEX24 ES subjects on all 3 tests at the 3-months interval and on 2 tests at the 6- months interval. Amongst ES-only subjects at the 3- months interval, FLEX28 ES subjects significantly outscored FLEX20 ES subjects on all 3 tests and the FLEX24 ES subjects on 2 tests. At the-6 months interval, FLEX28 ES subjects still exceeded the other ES-only subjects although the difference did not reach significance.ConclusionsAmong ES-only users, the FLEX28 ES users had the best speech comprehension scores, at the 3- months appointment and tendentially at the 6 months appointment. EAS users showed significantly better speech comprehension results compared to ES-only users with the same short electrodes.

Evaluation of the bimodal benefit in a large cohort of cochlear implant subjects using a contralateral hearing aid.

To investigate the benefit of contralateral residual hearing in a large group of cochlear implant recipients with different degrees of residual hearing. One hundred and forty-one adult patients (age in years: mean 58.82, min 16.27, max 88.20) wearing a cochlear implant and a contralateral hearing aid, bimodal. Rehabilitative. All 141 patients underwent speech perception testing in quiet and noise with cochlear implant (CI) alone, and with CI and hearing aid (HA). Additionally, pure-tone air conduction threshold levels were measured in all subjects. The bimodal benefit was analyzed and correlations to the hearing threshold for different audiometric frequencies were calculated. Comparison between the scores for CI alone and CI + HA showed statistically significant advantages (p < 0.0001) in all four tests. The benefit for sentences in noise to each individual patient showed a negative correlation with the hearing threshold level of 125 Hz and 250 Hz, using a linear regression analysis applying the Spearman's rho correlation coefficient (r = -0.32, -0.232), and a significant difference at p = 0.006, p = 0.007. The correlations involving speech understanding in sentences in noise, and the hearing level of 500 Hz and above, are not significant for the benefit obtained with a contralateral hearing aid. The benefit of combined electric and acoustic hearing in bimodally fitted subjects depends mainly on residual hearing in the low-frequency range below 500 Hz. For bimodal fitting to yield significant benefits, hearing loss in the contralateral ear should not exceed 80 dB HL in the low frequencies.

Toward hearing preservation in cochlear implant surgery.

To summarize the recent medical literature related to the feasibility of hearing preservation after cochlear implantation and to identify variables that may influence hearing preservation in the implanted ear as well as the hearing perception outcomes. The published data provide evidence that hearing preservation in the implanted ear yields significantly higher levels of speech recognition in complex listening environments than having just monaural acoustic hearing. There is ample evidence that hearing preservation is feasible and the reported rate is 50-89% in the low frequencies. This rate tends to be stable over time, except for a small percentage that diminishes around 3 months of follow-up. However, factors or variables which influence hearing preservation are yet unknown. Variables such as patient age, degree of residual hearing, insertion depth, insertion speed, duration of profound high frequency deafness and electrode design have been proposed. Much attention has been focused on hearing preservation in the implanted ear. Thus, investigations into electrode array design, surgical technique and pharmacological management have been undertaken. Minimizing damage in the inner ear not only enhances the possibility for hearing preservation and better performance in complex listening scenarios but also conserves inner ear structures for future treatments.

Round Window Electrocochleography Just Before Cochlear Implantation

Electrocochleography (ECoG) to acoustic stimuli can differentiate relative degrees of cochlear responsiveness across the population of cochlear implant recipients. The magnitude of the ongoing portion of the ECoG, which includes both hair cell and neural contributions, will correlate with speech outcomes as measured by results on CNC word score tests. Postoperative speech outcomes with cochlear implants vary from almost no benefit to near normal comprehension. A factor expected to have a high predictive value is the degree of neural survival. However, speech performance with the implant does not correlate with the number and distribution of surviving ganglion cells when measured postmortem. We will investigate whether ECoG can provide an estimate of cochlear function that helps predict postoperative speech outcomes. An electrode was placed at the round window of the ear about to be implanted during implant surgery. Tone bursts were delivered through an insert earphone. Subjects included children (n = 52, 1-18 yr) and postlingually hearing impaired adults (n = 32). Word scores at 6 months were available from 21 adult subjects. Significant responses to sound were recorded from almost all subjects (80/84 or 95%). The ECoG magnitudes spanned more than 50 dB in both children and adults. The distributions of ECoG magnitudes and frequencies were similar between children and adults. The correlation between the ECoG magnitude and word score accounted for 47% of the variance. ECoGs with high signal-to-noise ratios can be recorded from almost all implant candidates, including both adult and pediatric populations. In postlingual adults, the ECoG magnitude is more predictive of implant outcomes than other nonsurgical variables such as duration of deafness or degree of residual hearing.

Correlation between genotype and phenotype in patients with bi‐allelic SLC26A4 mutations

Mutation of SLC26A4 is the most common cause of prelingual hearing loss in East Asia. Patients with SLC26A4 mutations have variable phenotypes ranging from non-syndromic hearing loss to Pendred syndrome. Here, we analyzed the correlation between genotype and various inner ear phenotypes and found a possible underlying mechanism. This study included 111 patients with bi-allelic SLC26A4 mutations who had bilateral enlarged vestibular aqueduct (EVA) and hearing loss. p.H723R (61%), c.919-2A>G (24%), and p.T410M (4%) were the most common mutations in Korean patients with EVAs. Residual hearing in patients with c.919-2A>G or p.T410M mutations was better than that of patients with p.H723R homozygous mutations. Interestingly, quantitative polymerase chain reaction showed normal pendrin transcript (6-17% of normal levels) was produced from patients with c.919-2A>G homozygous mutations. Surface expression ratio of pendrin and residual anion exchange activity were higher in cells transfected with p.T410M in comparison to cells transfected with p.H723R. These results suggest that there is a correlation between degree of residual hearing and the SLC26A4 genotype commonly found in the East Asian population.

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

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.

TeenEARS: Development of a pilot assessment battery for cochlear implanted adolescents

Changes in selection criteria have led to the inclusion of pre-lingually deafened adolescents as potential cochlear implant candidates, depending on their degree of residual hearing, access to and use of acoustic amplification, use of oral communication, and other factors such as motivation and support. Outcomes results in adolescents vary widely, and it has become evident that there is a need for a test battery that can assess a wide range of skills over time. This article presents the development and validation of one such test battery: TeenEARS. Eleven tests were assessed for inclusion in the test battery. Consideration was given to the ability of the test to measure improvement over time; the fact that there needed to be easier and more difficult tests in terms of language, communication and listening; the need for closed and open-set assessments; and a range of listening tasks: from sounds to conversational language. Data on 23 adolescents assessed and judgment based on clinical experience resulted in eight tests being included in the TeenEARS test battery. Copyright © 2008 John Wiley & Sons, Ltd.

TeenEARS: Development of a pilot assessment battery for cochlear implanted adolescents

Changes in selection criteria have led to the inclusion of pre-lingually deafened adolescents as potential cochlear implant candidates, depending on their degree of residual hearing, access to and use of acoustic amplification, use of oral communication, and other factors such as motivation and support. Outcomes results in adolescents vary widely, and it has become evident that there is a need for a test battery that can assess a wide range of skills over time. This article presents the development and validation of one such test battery: TeenEARS. Eleven tests were assessed for inclusion in the test battery. Consideration was given to the ability of the test to measure improvement over time; the fact that there needed to be easier and more difficult tests in terms of language, communication and listening; the need for closed and open-set assessments; and a range of listening tasks: from sounds to conversational language. Data on 23 adolescents assessed and judgment based on clinical experience resulted in eight tests being included in the TeenEARS test battery. Copyright © 2008 John Wiley & Sons, Ltd.

An “Endosteal Electrode” for Cochlear Implantation in Cases with Residual Hearing? Feasibility Study: Preliminary Temporal Bone Experiments

Over the years, an increasing number of patients with some degree of residual hearing have received cochlear implants. In these cases, the marginal benefit provided by hearing aids alone is not sufficient; however, as experience has already shown, when hearing aids are used in combination with a cochlear implant, more benefit may be obtained. As a prerequisite, this requires that residual hair cell function must remain intact postoperatively. One of the European pioneers of cochlear implants, Ernst Lehnhardt, questioned whether residual hearing might better be preserved if the implanted electrode permits the fluid-filled inner ear space to remain intact. Subsequently, he proposed insertion of a very flat electrode array design into the extraluminal space between the spiral ligament and the bony cochlear wall (endosteum). Our study aimed to determine whether it is feasible to insert an endosteal electrode model intracochlearly but extraluminarily, anatomically, and ultimately surgically and to determine the impact on surrounding intracochlear structures. Insertion of two silicon models of an endosteal electrode were carried out in 15 human temporal bones. Histologic examination of the temporal bones after electrode insertion was performed on both fresh and fixed specimens to determine whether the desired anatomic site of insertion was achieved. In combination with light reflected and electron microscopic techniques, the extent to which the surrounding structures were impacted was also examined. Successful insertion of the prototype silicon endosteal electrodes was performed intracochlearly and extraluminarly in 11 of the 15 temporal bone specimens, confirming the anatomic feasibility of insertion into the crevice between the spiral ligament and endosteum. On the basis of the anatomy of the human temporal bone, insertion of an "endosteal electrode" is feasible. Subsequently, in vivo animal studies are needed to determine the physical effects of insertion of an endosteal electrode design prototype upon the functionality of the surrounding intracochlear structures and in particularly the ability to preserve hearing function.

Cochlear Implantation in Patients with Substantial Residual Hearing

Cochlear implantation is an effective means for providing auditory rehabilitation in adult patients with severe to profound sensorineural hearing loss. It has been hypothesized that patients with substantial, preoperative residual hearing would be excellent cochlear implant candidates because of surviving neural populations and a lack of auditory deprivation. The purpose of this study is to describe the outcomes of patients with substantial residual hearing who have undergone cochlear implantation. Retrospective chart review of patients with substantial preoperative residual hearing who underwent cochlear implantation. Chart reviews were completed for patients with substantial residual hearing who underwent cochlear implantation (City University of New York Sentence Test [CUNY] > 60%, Hearing in Noise Test sentences presented in quiet [HINTQ] > 50%, or Consonant-Nucleus-Consonant [CNC] > 20% in the ear to be implanted). Preoperative and postoperative measures of audiologic performance as well as complications were assessed. All 12 patients who met inclusion criteria ultimately surpassed their preoperative aided performance level after implantation and gained significant benefit from their cochlear implant. At 6 months postimplantation, mean CUNY, HINTQ, and CNC scores were 93%, 78%, and 48% in the implant ear alone, respectively. However, progress was slower than expected for many patients, and at least one patient took 1 year to surpass his preoperative performance level. There were no complications from surgery in this selected group of patients. Patients with some degree of residual hearing do benefit from cochlear implantation. However, there may be an initial decline in performance as compared with preoperative levels. This decline is overcome in time in this patient population. These patients need to be counseled accordingly.

Significance of Hearing Preservation in Acoustic Neuroma Surgery

In the past 10 years, 43 patients with acoustic neuroma have been operated on by the middle cranial fossa approach. In all cases, meticulous care was taken to preserve the cochlear function regardless of the degree of preoperative hearing disorder. Thirty-nine of 43 patients had various degrees of residual hearing; hearing was preserved in 16 of these (41%). The best result was obtained in patients with a tumor located less than 1 cm from the porus. The hearing preservation rate was 64% (11/17). The patients recovered hearing acuity quite well, especially at low frequencies in 2 cases who had a pure tone hearing level of more than 50 dB and less than 50% of speech discrimination. These 2 cases had a history of sudden deafness that was intractable 5 months preoperatively. Thus it is not correct to set certain criteria for hearing preservation for patients whose preoperative hearing may not be serviceable.

Coarticulation in the temporal domain: evidence from Telugu-speaking prelingually deaf children

This paper examines certain aspects of segmental and temporal coarticulation in the speech of six school-going deaf children whose native language is Telegu. Drawing on notions such as inter-gestural coordination, articulatory kinematics, phonetic sonority and vocal-tract impedance, it was hypothesised that the extent of segmental and temporal coarticultory effects in this language would depend on (l) the rhythmic status of a syllable within a word and (2) the degree of residual hearing and lip-reading skills of the subjects. The results, demonstrating that deletion of an intervening consonant in the medial position of words with geminate consonants (i.e. CVCCV words) and clusters (i.e. CVC1C2V words) contribute to prolongation of the vowel preceding the deleted consonant (resulting in CV:CV structures) and that this is particularly true in the speech of children with poor residual hearing and poor lip-reading ability, essentially supported the hypothesis. The implications of the results of this study are discussed in the light of existing theories of co articulation and suggestions are made for future research.