International Consensus Statements on Intraoperative Testing for Cochlear Implantation Surgery.

OBJECTIVES: A wide variety of intraoperative tests are available in cochlear implantation. However, no consensus exists on which tests constitute the minimum necessary battery. We assembled an international panel of clinical experts to develop, refine, and vote upon a set of core consensus statements. DESIGN: A literature review was used to identify intraoperative tests currently used in the field and draft a set of provisional statements. For statement evaluation and refinement, we used a modified Delphi consensus panel structure. Multiple interactive rounds of voting, evaluation, and feedback were conducted to achieve convergence. RESULTS: Twenty-nine provisional statements were included in the original draft. In the first voting round, consensus was reached on 15 statements. Of the 14 statements that did not reach consensus, 12 were revised based on feedback provided by the expert practitioners, and 2 were eliminated. In the second voting round, 10 of the 12 revised statements reached a consensus. The two statements which did not achieve consensus were further revised and subjected to a third voting round. However, both statements failed to achieve consensus in the third round. In addition, during the final revision, one more statement was decided to be deleted due to overlap with another modified statement. CONCLUSIONS: A final core set of 24 consensus statements was generated, covering wide areas of intraoperative testing during CI surgery. These statements may provide utility as evidence-based guidelines to improve quality and achieve uniformity of surgical practice.

Holistic assessment of cochlear implant outcomes using the international classification of functioning disability and health model: data analysis of a longitudinal prospective multicenter study.

PURPOSE: To study outcome after cochlear implantation using the Cochlear Implant (CI) outcome assessment protocol based on the International Classification of Functioning, Disability and Health (ICF) model (CI-ICF). METHODS: Raw data of a prospective, longitudinal, multicenter study was analyzed. Seventy-two CI candidates were assessed preoperatively and six months postoperatively using the CI-ICF protocol. Following tools were used: (1) Work Rehabilitation Questionnaire (WORQ), (2) Abbreviated Profile of Hearing Aid Benefit (APHAB), (3) Audio Processor Satisfaction Questionnaire (APSQ), (4) Speech, Spatial, and Qualities of Hearing Scale (SSQ12), (5) Hearing Implant Sound Quality Index (HISQUI19), (6) Nijmegen CI Questionnaire (NCIQ) (7) pure tone audiometry, (8) speech audiometry, (9) sound localization. RESULTS: There was a significant improvement of speech discrimination in quiet (p = 0.015; p < 0.001) and in noise (p = 0.041; p < 0.001), sound detection (p < 0.001), tinnitus (p = 0.026), listening (p < 0.001), communicating with-receiving-spoken messages (p < 0.001), conversation (p < 0.001), family relationships (p < 0.001), community life (p = 0.019), NCIQ total score and all subdomain scores (p < 0.001). Subjective sound localization significantly improved (p < 0.001), while psychometric sound localization did not. There was no significant subjective deterioration of vestibular functioning and no substantial change in sound aversiveness. CI users reported a high level of implant satisfaction postoperatively. CONCLUSION: This study highlights the positive impact of cochlear implantation on auditory performance, communication, and subjective well-being. The CI-ICF protocol provides a holistic and comprehensive view of the evolution of CI outcomes.

Minimum intraoperative testing battery for cochlear implantation: the international practice trend.

PURPOSE: In cochlear implantation (CI) surgery, there are a wide variety of intraoperative tests available. However, no clear guide exists on which tests must be performed as the minimum intraoperative testing battery. Toward this end, we studied the usage patterns, recommendations, and attitudes of practitioners toward intraoperative testing. METHODS: This study is a multicentric international survey of tertiary referral CI centers. A survey was developed and administered to a group of CI practitioners (n = 34) including otologists, audiologists and biomedical engineers. Thirty six participants were invited to participate in this study based on a their scientific outputs to the literature on the intraoperative testing in CI field and based on their high load of CI surgeries. Thirty four, from 15 countries have accepted the invitation to participate. The participants were asked to indicate the usage trends, perceived value, influence on decision making and duration of each intraoperative test. They were also asked to indicate which tests they believe should be included in a minimum test battery for routine cases. RESULTS: Thirty-two (94%) experts provided responses. The most frequently recommended tests for a minimum battery were facial nerve monitoring, electrode impedance measurements, and measurements of electrically evoked compound action potentials (ECAPs). The perceived value and influence on surgical decision-making also varied, with high-resolution CT being rated the highest on both measures. CONCLUSION: Facial nerve monitoring, electrode impedance measurements, and ECAP measurements are currently the core tests of the intraoperative test battery for CI surgery.

Outcomes of Cochlear Implantation Using FLEX26 Electrode: Audiological Results and Quality of Life after 12 Months.

INTRODUCTION: The electrode length is one of the many factors impacted on results of cochlear implantation. Among lateral wall flexible electrode arrays the latest one is FLEX26 (MED-EL GmbH, Innsbruck, Austria). The main aim of the study was to evaluate the preservation of residual hearing, the level of speech understanding, and quality of life after cochlear implantation with FLEX26 electrode array. METHODS: The study was conducted in a tertiary referral centre. Fifty-two patients implanted unilaterally with FLEX26, including 10 EAS patients (electric acoustic stimulation) and 42 ES patients (electric stimulation). The intervention was minimally invasive cochlear implantation via the round window. Pure-tone audiometry (0.125-8 kHz) was performed preoperatively and at 1, 6, and 12 months postoperatively. Twelve-month hearing preservation was established using HEARRING group formula. Quality of life was measured with AQoL-8D (Assessment of Quality of Life-8 Dimensions) pre- and postoperatively. RESULTS: Residual hearing was preserved in 88.8% EAS patients. Quality of life was significantly better postoperatively in comparison to preoperative period (the effect size for overall quality of life was 0.49). Especially, it increased in relationships and senses dimensions (the effect sizes 0.47 and 0.44, respectively). CONCLUSION: Preservation of residual hearing can be achieved in the majority of patients implanted with FLEX26. Improvement of quality of life was also documented. FLEX26 seems to be an option for surgeons who seek an electrode providing sufficient cochlear coverage.

New technology can benefit established middle ear implant users: Samba 2 vs previous models of audio processors for Vibrant Soundbridge.

INTRODUCTION: The Vibrant Soundbridge (VSB) is a semi-implantable hearing aid for patients with various types of hearing loss and has been available for over 25 years. Recently, new audio processors with advanced signal processing, noise reduction, and multi-microphone technology have appeared. The aim of this study is to compare the benefits of using the newest Samba 2 processor to the previous generation processors in a group of experienced VSB users. METHODS: There were 22 experienced VSB users (mean time of using VSB was 9 years, SD = 2) who had their processor (D404 or Amadé) upgraded to the newest model (Samba 2). The mean age of the subjects was 56 years (SD = 20). Assessments were made by free-field audiometry, speech reception in quiet and noise, and Patient-Reported Outcome Measures (PROMs). RESULTS: Hearing tests in free field showed statistically significant improvements in hearing sensitivity and speech discrimination in quiet and noise with the Samba 2 audio processor compared to the earlier technology. PROMs confirmed the benefits of using the newest audio processor and there was more satisfaction in terms of usability. CONCLUSIONS: Access to modern technology for VSB patients provides measurable benefits.

Can an individual with low frequency hearing in the candidate ear benefit from a cochlear implant even if they have normal hearing in the other ear?

PURPOSE: To determine hearing preservation and subjective benefit after cochlear implant (CI) surgery in patients with low frequency hearing in the ear to be implanted (i.e., they have partial deafness, PD) and close to normal hearing in the other. METHODS: There were two study groups. The test group was made up of 12 adult patients (mean age 43.4 years; SD 13.6) with normal hearing or mild hearing loss in one ear, and with PD in the ear to be implanted. The reference group consisted of 12 adult patients (mean age 44.5 years; SD 14.1) who had PD in both ears and who underwent unilateral implantation in their worse ear. Hearing preservation was assessed 1 and 14 months after CI surgery using the Skarzynski Hearing Preservation Classification System. The APHAB questionnaire was used to evaluate the benefit from the CI. RESULTS: The differences in HP% between the groups were not significant: mean hearing preservation (HP%) in the test group was 82% one month after CI surgery and 75% some 14 months after implantation; corresponding results in the reference group were 71% and 69%. However, on the APHAB background noise subscale, the benefit in the test group was significantly larger than in the reference group. CONCLUSION: To a large extent it was possible to preserve low-frequency hearing in the implanted ear. This means that individuals with low frequency hearing in the implanted ear (partial deafness) and with normal hearing in the other generally received more benefits from cochlear implantation than did patients with partial deafness in both ears. We conclude that residual low frequency hearing in the ear to be implanted should not be considered a contraindication for a CI in a patient with single-sided deafness.

Validation of AQoL-8D: a health-related quality of life questionnaire for adult patients referred for otolaryngology.

PURPOSE: The purpose of the study was to validate the AQoL-8D questionnaire in the adult population of patients referred to an otolaryngology clinic. METHODS: AQoL-8D was translated into Polish. 463 patients (age18-80 years) with otolaryngological conditions were assessed with the AQoL-8D, SF-6D, and SWLS questionnaires. We investigated the item content-relevance, factor structure by means of Confirmatory Factor Analysis, corrected item-total correlations, Cronbach's alpha, Pearson correlation of the AQoL-8D scores with results from SF-6D and from the SWLS questionnaires. Finally, ANOVA was used to test the AQoL-8D ability to group the HRQoL of patients in terms of their otolaryngological management type. RESULTS: The median score of item content-relevance was 5.0 for all AQoL-8D items. Confirmatory Factor Analysis revealed the following fit indices: Comparative Fit Index = 0.81; Tucker-Lewis Index = 0.80; and Root Mean Square Error of Approximation = 0.07. Cronbach's alpha for AQoL-8D dimensions ranged from 0.48 to 0.79. Mean item-total correlations over all dimensions, super dimensions, and the instrument overall were higher than 0.3. There was a significant Pearson correlation between the results obtained with AQoL-8D and SF-6D (r = 0.68), and with AQoL-8D and SWLS (r = 0.43). A one-way ANOVA showed a significant effect of management type on HRQoL as measured by AQoL-8D [F(4,458) = 6.12, p < 0.001] CONCLUSION: AQoL-8D provides valid and reliable measures of HRQoL in patients undergoing otolaryngological treatment. Because it is a generic questionnaire, it is possible to make general comparisons of otolaryngology outcomes with those from other subspecialties.

The COVID-19 pandemic and upgrades of CI speech processors for children: part II-hearing outcomes.

PURPOSE: To gauge the benefits to children of upgrading speech processors during the COVID-19 pandemic. METHODS: The study involved 297 children, aged from 7.3 to 18.0 years, whose processors were upgraded to either Nucleus 7 or Kanso 2, or to Sonnet 2 or Rondo 3. To document the benefits of the upgrades, a speech-in-noise discrimination test and Patient Reported Outcome Measures (PROMs) were used. RESULTS: There was a significant benefit from the newer processors in terms of speech discrimination in noise. Patient Reported Outcome Measures (PROMs) indicated less hearing disability, a higher level of functioning in everyday life situations, and more satisfaction with the new speech processor in social situations. CONCLUSION: There is a measurable improvement in performance when the devices are upgraded to the new technology.

The COVID-19 pandemic and upgrades of CI speech processors for children: part I-procedure of speech processor upgrade.

PURPOSE: To demonstrate the feasibility of upgrading speech processors during the COVID-19 pandemic. METHODS: Adopting concepts from "lean thinking", we optimized hospital workflows to allow speech processors to be upgraded despite the obstacles arising from national guidelines for COVID-19 prevention. The study involved 297 children, aged from 7.3 to 18.0 years, whose processors were upgraded on five consecutive Saturdays during a time of peak COVID-19 in Poland. RESULTS: The optimized workflow allowed us to conduct speech processor upgrades during a time of peak COVID-19 in Poland. The upgrades were conducted as scheduled, patient flow was smooth, appropriate social distancing was kept, and no reports of COVID-19 infection in our patients in the 2 weeks after their visit were received. CONCLUSION: Upgrading of speech processors in children is still feasible under coronavirus conditions.

Effect on vestibular function of cochlear implantation by partial deafness treatment-electro acoustic stimulation (PDT-EAS).

PURPOSE: Although the cochlear implantation procedure does not interfere with vestibular structures directly, both the vestibulum and the cochlea share the same inner ear fluid space, and this fluid may be responsible for transferring possibly damaging forces from one to the other. The purpose of the study is to assess postoperative vestibular function after partial deafness treatment-electro-acoustic stimulation (PDT-EAS) cochlear implantation. METHODS: Fifty-five patients were included in the study (30 females, 25 males, age 11-80, mean 41.8 ± 19.35). cVEMP and oVEMP were performed preoperatively and 1-3 months after cochlear implantation. Caloric and vHIT tests were conducted preoperatively and 4-6 months after cochlear implantation. RESULTS: Our study shows that, based on a wide range of electrodes, use of PDT-EAS is protective in terms of preserving vestibular function. It gives a rate of saccular damage of 15.79%, utricular damage of 19.04%, and a horizontal semicircular canal response reduction of 15.79%. CONCLUSIONS: PDT-EAS is protective in terms of preserving vestibular function. Nevertheless, it should be emphasized that the risk of vestibular damage cannot be totally eliminated even when hearing preservation techniques are adopted.

Electro-Natural Stimulation in Partial Deafness Treatment of Adult Cochlear Implant Users: Long-Term Hearing Preservation Results.

BACKGROUND: Due to the constant development of technology and medicine, the eligibility criteria for cochlear implantation (CI) are undergoing gradual expansion. OBJECTIVES: To provide long-term hearing preservation (HP) results for partial deafness treatment (PDT) of a group of adults using electro-natural stimulation (ENS). METHODS: We examined a database of medical records of patients who underwent CI in a single ENT center. We identified 12 adults (3 men and 9 women) who fitted the PDT-ENS classification. To calculate HP, we used the -HEARRING consensus and conducted statistical analyses using SPSS v24. RESULTS: In the long-term follow-up, 7 of 12 patients had complete HP and the remaining 5 had partial HP. None of the patients experienced significant hearing impairment. A significant improvement in speech understanding in both quiet and noise conditions was also observed. CONCLUSIONS: The use of minimally invasive surgery leads to excellent HP results in PDT-ENS patients, enabling them to enjoy the benefits of good speech discrimination which they would be unable to get from traditional hearing aids. Our findings support extending the inclusion criteria for CI to include this new group of patients who would otherwise obtain only limited benefit from conventional hearing aids.

Effects of Hearing Impairment and Hearing Aid Amplification on Listening Effort: A Systematic Review.

OBJECTIVES: To undertake a systematic review of available evidence on the effect of hearing impairment and hearing aid amplification on listening effort. Two research questions were addressed: Q1) does hearing impairment affect listening effort? and Q2) can hearing aid amplification affect listening effort during speech comprehension? DESIGN: English language articles were identified through systematic searches in PubMed, EMBASE, Cinahl, the Cochrane Library, and PsycINFO from inception to August 2014. References of eligible studies were checked. The Population, Intervention, Control, Outcomes, and Study design strategy was used to create inclusion criteria for relevance. It was not feasible to apply a meta-analysis of the results from comparable studies. For the articles identified as relevant, a quality rating, based on the 2011 Grading of Recommendations Assessment, Development, and Evaluation Working Group guidelines, was carried out to judge the reliability and confidence of the estimated effects. RESULTS: The primary search produced 7017 unique hits using the keywords: hearing aids OR hearing impairment AND listening effort OR perceptual effort OR ease of listening. Of these, 41 articles fulfilled the Population, Intervention, Control, Outcomes, and Study design selection criteria of: experimental work on hearing impairment OR hearing aid technologies AND listening effort OR fatigue during speech perception. The methods applied in those articles were categorized into subjective, behavioral, and physiological assessment of listening effort. For each study, the statistical analysis addressing research question Q1 and/or Q2 was extracted. In seven articles more than one measure of listening effort was provided. Evidence relating to Q1 was provided by 21 articles that reported 41 relevant findings. Evidence relating to Q2 was provided by 27 articles that reported 56 relevant findings. The quality of evidence on both research questions (Q1 and Q2) was very low, according to the Grading of Recommendations Assessment, Development, and Evaluation Working Group guidelines. We tested the statistical evidence across studies with nonparametric tests. The testing revealed only one consistent effect across studies, namely that listening effort was higher for hearing-impaired listeners compared with normal-hearing listeners (Q1) as measured by electroencephalographic measures. For all other studies, the evidence across studies failed to reveal consistent effects on listening effort. CONCLUSION: In summary, we could only identify scientific evidence from physiological measurement methods, suggesting that hearing impairment increases listening effort during speech perception (Q1). There was no scientific, finding across studies indicating that hearing aid amplification decreases listening effort (Q2). In general, there were large differences in the study population, the control groups and conditions, and the outcome measures applied between the studies included in this review. The results of this review indicate that published listening effort studies lack consistency, lack standardization across studies, and have insufficient statistical power. The findings underline the need for a common conceptual framework for listening effort to address the current shortcomings.

Cochlear implantation in the elderly.

Hearing disorders become an increasingly important issue that influences quality of life and many other economic factors. Due to the prolongation of human life and the more active lifestyles of people in retirement age, there is an increasing requirement for the available treatment options of hearing loss in the aging population. The aim of this study was to compare the hearing preservation outcomes of adult patients implanted with the Cochlear™ Nucleus® CI422 when divided into two groups by age, younger and older than 65 years of age. The study cohort consisted of 62 patients implanted from January 2011 through December 2013 at our clinic. All patients were assessed and classified according to the hearing preservation classification. Comparing the results between subgroups, we observed that the degree of hearing preservation was greater in younger adults than in older adults. Results of this review may suggest that deeper insertion is to be recommended for an older population of cochlear implant recipients.

Cochlear implantation with the nucleus slim straight electrode in subjects with residual low-frequency hearing.

OBJECTIVES: To measure benefit in terms of speech recognition in quiet and in noise, and conservation of residual hearing in three groups of subjects implanted with the Nucleus Straight Research Array cochlear implant. This device incorporates the Nucleus Slim Straight electrode carrier designed to be easier to insert into the cochlea via the round window while potentially minimizing insertion trauma. DESIGN: The study was prospective, with sequential enrolment and within-subject repeated measures; 35 subjects were 15 to 84 years of age with varying levels of bilateral high-frequency HL. Subjects were divided into three groups (A, B, and C) according to preoperative air conduction hearing thresholds in the ear to implant at 500 Hz; A ≤ 50 (n = 11), 50 < B < 80 (n = 13), and C ≥ 80 (n = 11) dB HL. Speech recognition was assessed preoperatively and at intervals up to 1 year postimplantation. Hearing thresholds were monitored over time and CT scans were used to estimate electrode positions. RESULTS: Preoperative mean word recognition score was significantly greater for group A compared with group C in quiet (diff. 26.6%pts, p < 0.05), but not so in noise (diff. 7.9%pts, p = 0.72). However, a greater proportion of subjects in group A (81%) achieved a "worthwhile" gain in speech recognition score (>20%pts) in quiet compared with group C (63%). More importantly, for speech recognition in noise, all subjects in groups A and B achieved a >20%pts gain compared with only 73% in group C. Hearing in implanted ears was well conserved for low frequencies, both initially and up to 12 months postoperatively (15 dB median increase in thresholds 250 to 500 Hz). Only 3 of 35 (9%) cases lost all residual hearing in the implanted ear by 12 months. Where characteristic frequency corresponded to a position occupied by the electrode array, threshold increase was correlated with the preoperative hearing threshold (r = 0.7; p < 0.001) and closely approximated reported estimates of residual outer hair cell gain. For characteristic frequencies at positions apical to the electrode tip, the relation between threshold increase and residual hearing decreased in amplitude at 45 to 135 degrees (r = 0.42; p < 0.05), and disappeared at >135 degrees (r = 0.05; p > 0.05). CONCLUSION: Gains in speech recognition scores for subjects with better residual low-frequency hearing were greater or equal to those obtained by subjects with poorer residual hearing. Residual hearing after cochlear implantation with the Nucleus Slim Straight electrode array was well conserved across all three groups. It appears that the gain provided by outer hair cell function may be completely suppressed when an electrode array is in close proximity to the organ of Corti.

Direct round window stimulation with the Med-El Vibrant Soundbridge: 5 years of experience using a technique without interposed fascia.

The objective of this study was to present 5 years of surgical experience, and the extended results of hearing preservation (based on 3-year follow-up), with the Med-El Vibrant Soundbridge (VSB) in which the floating mass transducer (FMT) is placed directly against the round window membrane, and the fascia is used only as covering tissue to keep it in position. A retrospective survey of surgical and audiological data was conducted to evaluate the performance and stability of patient hearing, with audiometric measurements performed over fixed time intervals up to 36 months. 21 patients, aged 19-62 years (mean 48.4), with mixed or conductive, bilateral or unilateral hearing loss were included in this study. Surgical intervention involved monaural implantation of the Med-El VSB between 2006 and 2009. The results were assessed using pure tone audiometry. In 5 years of experience with the technique, no significant complications or device extrusion were observed except for two revision surgeries requiring FMT repositioning. In the 3-year follow-up, we observed stable hearing in the implanted ear. It is concluded that direct round window stimulation without interposed fascia is an alternative for patients with hearing impairment caused by chronic otitis media and/or lack of ossicles, especially after modified radical mastoidectomy. It allows good results in a selected group of patients, although further observation on a larger population is needed to confirm long-term validity and effectiveness.

Cochlear implantation with hearing preservation yields significant benefit for speech recognition in complex listening environments.

OBJECTIVE: The aim of this study was to assess the benefit of having preserved acoustic hearing in the implanted ear for speech recognition in complex listening environments. DESIGN: The present study included a within-subjects, repeated-measures design including 21 English-speaking and 17 Polish-speaking cochlear implant (CI) recipients with preserved acoustic hearing in the implanted ear. The patients were implanted with electrodes that varied in insertion depth from 10 to 31 mm. Mean preoperative low-frequency thresholds (average of 125, 250, and 500 Hz) in the implanted ear were 39.3 and 23.4 dB HL for the English- and Polish-speaking participants, respectively. In one condition, speech perception was assessed in an eight-loudspeaker environment in which the speech signals were presented from one loudspeaker and restaurant noise was presented from all loudspeakers. In another condition, the signals were presented in a simulation of a reverberant environment with a reverberation time of 0.6 sec. The response measures included speech reception thresholds (SRTs) and percent correct sentence understanding for two test conditions: CI plus low-frequency hearing in the contralateral ear (bimodal condition) and CI plus low-frequency hearing in both ears (best-aided condition). A subset of six English-speaking listeners were also assessed on measures of interaural time difference thresholds for a 250-Hz signal. RESULTS: Small, but significant, improvements in performance (1.7-2.1 dB and 6-10 percentage points) were found for the best-aided condition versus the bimodal condition. Postoperative thresholds in the implanted ear were correlated with the degree of electric and acoustic stimulation (EAS) benefit for speech recognition in diffuse noise. There was no reliable relationship among measures of audiometric threshold in the implanted ear nor elevation in threshold after surgery and improvement in speech understanding in reverberation. There was a significant correlation between interaural time difference threshold at 250 Hz and EAS-related benefit for the adaptive speech reception threshold. CONCLUSIONS: The findings of this study suggest that (1) preserved low-frequency hearing improves speech understanding for CI recipients, (2) testing in complex listening environments, in which binaural timing cues differ for signal and noise, may best demonstrate the value of having two ears with low-frequency acoustic hearing, and (3) preservation of binaural timing cues, although poorer than observed for individuals with normal hearing, is possible after unilateral cochlear implantation with hearing preservation and is associated with EAS benefit. The results of this study demonstrate significant communicative benefit for hearing preservation in the implanted ear and provide support for the expansion of CI criteria to include individuals with low-frequency thresholds in even the normal to near-normal range.

Partial deafness treatment with the nucleus straight research array cochlear implant.

INTRODUCTION: The Nucleus Straight Research Array (SRA) cochlear implant has a new 25-mm electrode carrier designed to minimize insertion trauma, in particular allowing easy insertion via the round window. The aims of this study were to measure preoperative to postoperative benefit in terms of speech recognition in quiet and in noise in three groups of patients (electrical complement, EC; electrical stimulation, ES; electro-acoustic stimulation, EAS) with varying levels of low-frequency hearing, and to evaluate the preservation of residual hearing after implantation with the SRA cochlear implant. METHODS: The study design was prospective with sequential enrolment and within-subject comparisons: 23 adult cochlear implant candidates were divided into three groups according to their level of preoperative residual hearing at 500 Hz (EC ≤50 dB; 50 dB < EAS < 80 dB; ES ≥80 dB). Monosyllabic word recognition using the SRA cochlear implant in combination with residual low-frequency hearing was assessed at 4 and 13 months after implantation. Hearing threshold levels were also monitored over time. RESULTS: Subjects across all three groups had significant improvements in speech recognition scores (i.e. >20 percentage points) both for listening in quiet (71% of subjects) and in noise (100% of subjects). The average score at 4 months after operation for words presented in quiet was 61.7%, and in 10 dB SNR noise 46.5%, compared to 34.4 and 10.6% preoperatively (p < 0.001). All subjects retained measurable hearing at 500 Hz in the implanted ear at 4 months after the operation; mean increases were 19, 29 and 1 dB for the EC, EAS and ES groups (n = 21). Across frequencies of 125-1000 Hz, the median increase in thresholds was 15 dB up to 13 months postoperatively (n = 15). CONCLUSIONS: Speech recognition performance of subjects with various levels of residual low-frequency hearing was significantly improved with the SRA cochlear implant. A high level and rate of hearing preservation was achieved with the SRA implanted using a round window surgical technique. Subjects with preoperative low-frequency hearing levels between 50 and 80 dB HL (EAS group) tended to lose more hearing than those with either better or worse hearing.

Multi-Frequency Intraoperative Monitoring of Hearing Preservation during Cochlear Implantation.

(1) Background: Current indications for cochlear implants (CIs) have expanded to include patients with appreciable low-frequency hearing. However, longitudinal results indicate that only one-third of these recipients retain full hearing preservation. In another words, the remaining two-thirds lose this facility either partially or fully. This points to the need to better understand the impact of cochlear implantation on cochlear integrity. Intracochlear electrocochleography (ECochG) involves the recording of electrical potentials generated in the inner ear in response to acoustic stimuli, and previous studies have shown that these potentials give an indication of residual inner ear function. Aim of the research: The aim is to monitor intracochlear ECochG during CI surgery and gain a better understanding of how the implant impacted inner ear function. A newly developed SPL Chirp was used for stimulation. (2) Methods: Intracochlear ECochG signals were measured in a subject with residual preoperative low-frequency hearing, while an electrode array was introduced into the cochlea and was continued until the round window was sealed. Afterwards, surgical events were reviewed with the surgeon; preoperative and postoperative radiological data and hearing thresholds were also evaluated. (3) Conclusions: Real-time intraoperative monitoring, with multifrequency evaluation and video recording, has the potential to allow surgeons and audiologists to continuously assess cochlear function. ECochG monitoring may be a useful tool during cochlear implantation to gain frequency-specific information on the status of the patient's hearing, assisting surgeons to lower hearing trauma during the operation.

In Vivo Basilar Membrane Time Delays in Humans.

To date, objective measurements and psychophysical experiments have been used to measure frequency dependent basilar membrane (BM) delays in humans; however, in vivo measurements have not been made. This study aimed to measure BM delays by performing intracochlear electrocochleography in cochlear implant recipients. Sixteen subjects with various degrees of hearing abilities were selected. Postoperative Computer Tomography was performed to determine electrode locations. Electrical potentials in response to acoustic tone pips at 0.25, 0.5, 1, 2, and 4 kHz and clicks were recorded with electrodes at the frequency specific region. The electrode array was inserted up to the characteristic cochlear frequency region of 250 Hz for 6 subjects. Furthermore, the array was inserted in the region of 500 Hz for 15 subjects, and 1, 2, and 4 kHz were reached in all subjects. Intracochlear electrocochleography for each frequency-specific tone pip and clicks showed detectable responses in all subjects. The latencies differed among the cochlear location and the cochlear microphonic (CM) onset latency increased with decreasing frequency and were consistent with click derived band technique. Accordingly, BM delays in humans could be derived. The BM delays increased systematically along the cochlea from basal to apical end and were in accordance with Ruggero and Temchin, 2007.

The Clinical Effect of Steroid Therapy on Preserving Residual Hearing after Cochlear Implantation with the Advanced Bionics HiRes Ultra 3D Cochlear Implant System.

(1) Background: The main aim of this study was to assess the clinical effectiveness of two different schemes of administration of steroids ((1) dexamethasone administered intravenously in comparison with (2) combination of steroid treatments: orally administered prednisone and intravenously administered dexamethasone) in comparison with a control group (no steroid administration) on hearing preservation (HP) in patients who underwent an Advanced Bionics cochlear implantation. (2) Methods: Thirty-five adult patients met the inclusion criteria. All patients were randomly divided into three subgroups depending on the scheme of steroid administration: (1) the first subgroup with only intravenously administered dexamethasone (0.1 mg per kg body weight twice a day for three days), (2) the second subgroup with a combination of methods of administration of steroids (intravenous and oral steroid therapy (dexamethasone, 0.1 mg/kg body weight twice a day plus prednisone, 1 mg/kg weight once a day for three days before surgery and after administration of dexamethasone (4th, 5th, 6th day) and after this time the dose of prednisone was reduced)) and (3) the third subgroup without steroid therapy (control group). The results were measured by pure tone audiometry (PTA) in three periods: (1) before implantation, (2) during activation of the processor (one month after implantation), and (3) 12 months after activation. Patients' hearing thresholds before implantation were on average 82 dB HL, 77 dB HL, and 88 dB HL, respectively. (3) Results: The majority of the patients from the first subgroup had hearing preserved partially (77.8%). A similar result was observed in the second study group (oral + i.v.) (partial hearing preservation was found in 61.5% of the participants). The opposite was true in the control group; a plurality of control patients (38.5%) had no measurable hearing 12 months after the activation of the processor. (4) Conclusions: Pharmacological treatment consisting of the administration of steroids in patients who had undergone cochlear implantation with the Advanced Bionics HiRes Ultra 3D cochlear implant system may be beneficial for preserving residual hearing in patients.