Benefits of the HiRes 120 coding strategy combined with the Harmony processor in an adult European multicentre study

The objective of the present study was to establish the estimated incidence of symptomatic nasal polyps within a defined geographic area. Over a 6-year period all polyp patients diagnosed for the first time ( n ¾ 252; 174 males, 78 females) were prospectively registered at the study clinic. An estimated background population from which the patients were recruited was defined. Polyps were diagnosed by endoscopic examination. The mean estimated incidences for all age groups were 0.86 and 0.39 patients per thousand per year for males and females, respectively. The incidence increased with age, reaching peaks of 1.68 and 0.82 patients per thousand per year for males and females, respectively in the age group 50-59 years. The overall estimated incidence of symptomatic nasal polyps was 0.627 patients per thousand per year. Five percent of the patients had antrochoanal polyps and these patients had a lower mean age at diagnosis than the other patients, of whom 41% also had unilateral presentation at the time of diagnosis. This study seems to give a fairly reliable estimated incidence of symptomatic nasal polyps for different age groups and provides results that do not contradict prevalence studies in the literature, making it useful in a clinical context.     

Speech perception in cochlear implant users with the HiRes 120 strategy: a systematic review

Despite technological advances employed in signal processing strategies, one of the remaining obstacles are spectral gap details on the information transmitted. Considering its importance in speech perception, researchers have investigated mechanisms to optimize spectral details through virtual spectral channels. The clinical application of this technique resulted in a new approach to signal processing - the HiRes 120.ObjectiveTo assess the auditory performance of cochlear implant users with the HiRes 120 strategy.MethodologyThe literature review was conducted in an electronic database, with standard bibliographic search in the year 2011, using specific keywords. In order to select and evaluate the scientific studies found in the search, we setup search containing the following aspects: type of study, subjects, intervention used and evaluation of the results.ConclusionScientific evidence points to an improvement in hearing performance in noisy environments with the HiRes 120 strategy, but this does not occur in quiet situations. The optimization of speech perception with this strategy is closely related to the cochlear implant user's age, to the time of sensory deprivation and the acclimatization time required to use the strategy's spectral information.     

Evaluation of the high-resolution speech coding strategy for the Clarion CII cochlear implant system

Four postlinguistically deafened adults were implanted with the Clarion CII cochlear implant with the HiFocus II electrode in an evaluation of performance with a new speech coding strategy (high resolution) compared with current speech coding strategies (multiple pulsatile sampler, continuous interleaved sampling, and simultaneous analog stimulation). These strategies were implemented in the Platinum speech processor from Advanced Bionics Corporation (Sylmar, CA). Postoperatively, subjects were fitted with the traditional coding strategies and over the first month were allowed to determine their strategy of choice. This strategy was used to evaluate open-set speech recognition performance at 1 month and 3 months postfitting. At 3 months postfitting, subjects were reprogrammed with the high-resolution strategy. They returned for speech recognition testing at 1 month and 3 months postfitting with this strategy. Performance was significantly better with the high-resolution strategy for all four subjects, particularly when listening to speech in background noise. This finding was in agreement with their strong preference for the high-resolution strategy, and all four patients continue to use the high-resolution strategy.     

Music perception in cochlear implant recipients: comparison of findings between HiRes90 and HiRes120

CONCLUSIONS: Increased spectral resolution via implementation of perceptual channels with HiRes120 (PSP) would seem to provide better perception of music than with standard HiRes, mainly from the point of view of music appreciation as recorded via the questionnaire. More specific tests are required for appreciation of timbre, preferably by application of protocols based on perceptual attributes using rating scales, which would not be biased by knowledge of music. OBJECTIVE: The objective of this study was to verify the hypothesis whereby the implementation of perceptual channels in HiRes120 may lead to an improvement in the perception of music, owing to an increase in spectral resolution. SUBJECTS AND METHODS: Music perception was studied in 12 adult subjects, making a comparison between performance with HiRes90 and HiRes120 with perceptual channels. Quality of perception, loudness and rhythm were all assessed via a questionnaire. Further tests included timbre recognition trials and pitch ranking. RESULTS: Whereas there was a significant improvement in appreciation of music as seen by the questionnaire, timbre and pitch trials seemed to be biased by various subjective factors and require further study using different criteria.     

言语编码策略升级对成年人工耳蜗使用者听觉效果影响的研究

目的　探讨言语编码策略升级对有经验人工耳蜗使用者听觉效果的影响趋势,以期为临床制定有效的人工耳蜗言语编码策略升级方案提供参考依据。方法　采用噪声下汉语普通话声调识别测试、普通话噪声下言语识别测试以及自行编制的声音质量自评问卷,对13例有经验成年人工耳蜗使用者言语编码策略升级后的声调识别能力、短句分辨能力以及声音质量和聆听感受进行3个月连续观测。以使用日常言语编码策略（即CIS+策略）的测试结果为参考值,以新言语编码策略（即精细结构编码策略）的测试 结果为目标值,分析言语编码策略升级对成年人工耳蜗使用者听觉效果的影响。结果　①声调识别能力：各测试阶段两种编码策略的声调识别测试成绩无显著差异,随着精细结构编码策略使用经验增加,测试成绩呈明显改善趋势[F（3,36）=5.201,P =0.004];②短句分辨能力：各测试阶段两种编码策略的言语识别测试成绩无显著差异,随精细结构编码策略使用经验增加,测试成绩略有提高[F（3,36）=2.450,P =0.079];③声音质量自评：更换言语编码策略对本组受试者的声音质量和聆听感受无不利影响（P =0.083）。随着精细结构编码策略使用经验增加,受试者认为声音质量更“饱满、丰富”、聆听感受更“容易、轻松”。结论　言语编程策略升级未对有经验人工耳蜗使用者的言语识别能力造成不良影响且存在潜在的改善作用。在临床工作中可参考患者主观意愿确定是否升级言语编程策略。     

Effects of stimulation rate with the Nucleus 24 ACE speech coding strategy

OBJECTIVE: The primary objective of the study was to determine whether individual cochlear implant recipients recognize speech better with an electrical stimulation rate of 720 or 1800 pulses per second per channel (pps/ch) using the Nucleus 24 Advanced Combination Encoder (ACE) speech coding strategy. The secondary objective was to determine, for each active electrode, the relation between psychophysical measures and MAP minimum and maximum stimulation levels for each rate, as well as the stability of MAP minimum and maximum levels during the study. DESIGN: Eight postlinguistically deaf adults implanted with the Nucleus 24 device participated in this study comparing the effect of a moderate (720 pps/ch) and a fast (1800 pps/ch) rate of electrical stimulation on speech recognition of words in quiet and sentences in noise presented at 50, 60, and 70 dB SPL in the laboratory and on listening to sound in everyday life over a 14-wk time period. At the beginning of the study, psychophysical measures (i.e., counted threshold and maximum acceptable loudness [MAL] levels) were obtained for each active electrode with each of the two rates to initially set MAP minimum and maximum stimulation levels. These levels were then adjusted to make speech and environmental sound clear and comfortable in everyday life. Threshold and MAL levels were obtained again half way through the study to monitor possible hearing changes. A four-phase test design for evaluation of speech recognition was followed; an equal number of subjects started with each of the two rates and alternated rates for each phase. In the last 2 wk of each phase, word and sentence scores were obtained, and subjects responded to a questionnaire. For the group, factorial analyses of variance were conducted for subject, stimulation rate, and time period (first two phases versus second two phases) for words, phonemes within words, and sentences at each level. Additional analyses were obtained for individual subjects. RESULTS: Group mean scores across time periods were significantly higher for 1800 pps/ch than 720 pps/ch for phonemes and sentences in noise at 50 dB SPL. There was no significant difference in scores for phonemes and sentences at 60 and 70 dB SPL or for words at any of the three levels. Group mean scores across stimulation rate were significantly higher during the second half than the first half of the study for words, phonemes, and sentences at 50 dB SPL. This result is consistent with subjects learning to recognize speech cues near threshold. A subject by rate interaction was seen for sentences at 70 dB SPL and for all three speech measures at 50 dB SPL. These interactions reflect the fact that two subjects performed significantly better with 720 pps/ch, whereas two other subjects performed significantly better with 1800 pps/ch. Responses to the questionnaire indicated that two subjects preferred 720 pps/ch, three preferred 1800 pps/ch, and three had no preference. The minimum and/or maximum levels in most subjects' final MAPs differed from the psychophysical measures for both rates. Changes in Current Level at threshold and MAL were minimal from the first to the second half of the study for each rate. CONCLUSIONS: More than half the subjects preferred one of the two rates for use in everyday life, and four subjects performed significantly better with one of the two rates on at least one test measure. These findings underscore the clinical importance of creating MAPs for each implant recipient that include at least a moderate and a fast rate within ACE during the first months of device use. Given the significant learning effects for soft speech that occurred over several weeks use of each rate in this study, it is suggested that each rate be used alone for a week or two before comparing them and deciding which provides more benefit. In addition, adjustments in an individual's MAP minimum and maximum levels are needed at each rate so soft and normal conversational speech as well as loud sound are clear and comfortable in everyday life.     

Effect of frequency boundary assignment on speech recognition with the Nucleus 24 ACE speech coding strategy

The choice of frequency boundaries for the analysis channels of cochlear implants has been shown to impact the speech perception performance of adult recipients (Skinner et al, 1995; Fourakis et al, 2004). While technological limitations heretofore have limited the clinical feasibility of investigating novel frequency assignments, the SPEAR3 research processor affords the opportunity to investigate an unlimited number of possibilities. Here, four different assignments are evaluated using a variety of speech stimuli. All participants accommodated to assignment changes, and no one assignment was significantly preferred. The results suggest that better performance can be achieved using a strategy whereby (1) there are at least 7-8 electrodes allocated below 1000 Hz, (2) the majority of remaining electrodes are allocated between 1100-3000 Hz, and (3) the region above 3 kHz is represented by relatively few electrodes (i.e., 1-3). The results suggest that such frequency assignment flexibility should be made clinically available.     

Postlingual adult performance in noise with HiRes 120 and ClearVoice Low,Medium, and High

Abstract

Objectives

The study's objectives were to evaluate speech recognition in multiple listening conditions using several noise types with HiRes 120 and ClearVoice (Low, Medium, High) and to determine which ClearVoice program was most beneficial for everyday use.

Methods

Fifteen postlingual adults attended four sessions; speech recognition was assessed at sessions 1 and 3 with HiRes 120 and at sessions 2 and 4 with all ClearVoice programs. Test measures included sentences presented in restaurant noise (R-SPACE^TM), in speech-spectrum noise, in four- and eight-talker babble, and connected discourse presented in 12-talker babble. Participants completed a questionnaire comparing ClearVoice programs.

Results

Significant group differences in performance between HiRes 120 and ClearVoice were present only in the R-SPACE^TM; performance was better with ClearVoice High than HiRes 120. Among ClearVoice programs, no significant group differences were present for any measure. Individual results revealed most participants performed better in the R-SPACE^TM with ClearVoice than HiRes 120. For other measures, significant individual differences between HiRes 120 and ClearVoice were not prevalent. Individual results among ClearVoice programs differed and overall preferences varied. Questionnaire data indicated increased understanding with High and Medium in certain environments.

Discussion

R-SPACE^TM and questionnaire results indicated an advantage for ClearVoice High and Medium. Individual test and preference data showed mixed results between ClearVoice programs making global recommendations difficult; however, results suggest providing ClearVoice High and Medium and HiRes 120 as processor options for adults willing to change settings. For adults unwilling or unable to change settings, ClearVoice Medium is a practical choice for daily listening.     

Speech and music perception with the new fine structure speech coding strategy: preliminary results

Conclusions. Taking into account the excellent results with significant improvements in the speech tests and the very high satisfaction of the patients using the new strategy, this first implementation of a fine structure strategy could offer a new quality of hearing with cochlear implants (CIs). Objective. This study consisted of an intra-individual comparison of speech recognition, music perception and patient preference when subjects used two different speech coding strategies with a MedEl Pulsar CI: continuous interleaved sampling (CIS) and the new fine structure processing (FSP) strategy. In contrast to envelope-based strategies, the FSP strategy also delivers subtle pitch and timing differences of sound to the user and is thereby supposed to enhance speech perception in noise and increase the quality of music perception. Patients and methods. This was a prospective study assessing performance with two different speech coding strategies. The setting was a CI programme at an academic tertiary referral centre. Fourteen post-lingually deaf patients using a MedEl Pulsar CI with a mean CI experience of 0.98 years were supplied with the new FSP speech coding strategy. Subjects consecutively used the two different speech coding strategies. Speech and music tests were performed with the previously fitted CIS strategy, immediately after fitting with the new FSP strategy and 4, 8 and 12 weeks later. The main outcome measures were individual performance and subjective assessment of two different speech processors. Results. Speech and music test scores improved statistically significantly after conversion from CIS to FSP strategy. Twelve of 14 patients preferred the new FSP speech processing strategy over the CIS strategy.     

Speech and music perception with the new fine structure speech coding strategy: preliminary results

CONCLUSIONS: Taking into account the excellent results with significant improvements in the speech tests and the very high satisfaction of the patients using the new strategy, this first implementation of a fine structure strategy could offer a new quality of hearing with cochlear implants (CIs). OBJECTIVE: This study consisted of an intra-individual comparison of speech recognition, music perception and patient preference when subjects used two different speech coding strategies with a MedEl Pulsar CI: continuous interleaved sampling (CIS) and the new fine structure processing (FSP) strategy. In contrast to envelope-based strategies, the FSP strategy also delivers subtle pitch and timing differences of sound to the user and is thereby supposed to enhance speech perception in noise and increase the quality of music perception. PATIENTS AND METHODS: This was a prospective study assessing performance with two different speech coding strategies. The setting was a CI programme at an academic tertiary referral centre. Fourteen post-lingually deaf patients using a MedEl Pulsar CI with a mean CI experience of 0.98 years were supplied with the new FSP speech coding strategy. Subjects consecutively used the two different speech coding strategies. Speech and music tests were performed with the previously fitted CIS strategy, immediately after fitting with the new FSP strategy and 4, 8 and 12 weeks later. The main outcome measures were individual performance and subjective assessment of two different speech processors. RESULTS: Speech and music test scores improved statistically significantly after conversion from CIS to FSP strategy. Twelve of 14 patients preferred the new FSP speech processing strategy over the CIS strategy.     

Effect of frequency boundary assignment on vowel recognition with the Nucleus 24 ACE speech coding strategy

Two speech processor programs (MAPs) differing only in electrode frequency boundary assignments were created for each of eight Nucleus 24 Cochlear Implant recipients. The default MAPs used typical frequency boundaries, and the experimental MAPs reassigned one additional electrode to vowel formant regions. Four objective speech tests and a questionnaire were used to evaluate speech recognition with the two MAPs. Results for the closed-set vowel test and the formant discrimination test showed small but significant improvement in scores with the experimental MAP. Differences for the Consonant-Vowel Nucleus-Consonant word test and closed-set consonant test were nonsignificant. Feature analysis revealed no significant differences in information transmission. Seven of the eight subjects preferred the experimental MAP, reporting louder, crisper, and clearer sound. The results suggest that Nucleus 24 recipients should be given an opportunity to compare a MAP that assigns more electrodes in vowel formant regions with the default MAP to determine which provides the most benefit in everyday life.     

Optimized speech understanding with the continuous interleaved sampling speech coding strategy in patients with cochlear implants: effect of variations in stimulation rate and number of channels

The purpose of this study was to investigate the effect of systematic variations in stimulation rate and number of channels on speech understanding in 13 patients with cochlear implants who used the continuous interleaved sampling speech coding strategy. Reducing the stimulation rate from 1,515 to 1,730 pulses per second per channel to 600 pulses per second per channel resulted in decreased overall performance; the understanding of monosyllables and consonants was more affected than the understanding of vowels. Reducing the number of active channels below 7 or 8 channels decreased speech understanding; the identification of vowels and monosyllables was most affected. We conclude that vowel recognition with the continuous interleaved sampling strategy relies on spectral cues more than on temporal cues, increasing with the number of active channels, whereas consonant recognition is more dependent on temporal cues and stimulation rate.     

Short-term study of the effect of speech coding strategy on the auditory performance of pre- and post-lingually deafened adults implanted with the Clarion CII

OBJECTIVE: The auditory performance of cochlear implantees is linked to numerous variables, such as audiological characteristics, age and type of speech coding strategy. In recent years, many different ways of processing sounds have been developed, with possible implications for auditory performance. The purpose of this study was to evaluate the intra-individual differences of patients for speech perception tasks in quiet and in noise as a result of switching from a standard strategy [Continuous Interleaved Sampling (CIS)/Simultaneous Analog Strategy (SAS)] to Hi-Resolution (HiRes). MATERIAL AND METHODS:A total of 14 post-lingual adults implanted with the Clarion CII were selected for trials. At switch-on, six patients chose a CIS strategy and eight an SAS strategy. After an average period of 9.3 months, all patients were switched over to HiRes. All patients were tested (open-set mode) with bisyllabic words and sentences, in both quiet and noise [speech/noise ratio (SNR) = +10]. Testing was carried out after an initial period with the CIS/SAS strategy and 3 months after switching over to HiRes. RESULTS: After switch-over a significant improvement was seen for both speech in quiet (words +25.2%, sentences +10.8%) and speech in noise (words 44.8%, sentences 45.4%). CONCLUSION: Despite individual differences, all patients improved their performance with HiRes use, the greatest improvements being seen under unfavourable listening conditions (SNR = +10). Subjective improvements in speech discrimination and overall sound quality perception were reported even after the first week of HiRes use.     

Recent developments with the nucleus 22-electrode cochlear implant: a new two formant speech coding strategy and its performance in background noise

A clinical evaluation of speech processing strategies for the Nucleus 22-electrode cochlear implant showed improvements in understanding speech using the new FOF1F2 speech coding strategy instead of the F0F2 strategy. Significant improvement in closed-set speech recognition in the presence of background noise was an additional advantage of the new speech processing strategy.     

Effect of stimulation rate on speech perception in adult users of the Med-El CIS speech processing strategy

The primary aim of the study was to determine the effect of altering channel stimulation rate on the performance of adult cochlear implant users. Six adult users of the Med-El CIS processing strategy underwent tests of categorical identification of synthetic speech, tests of sentence recognition and tests of consonant recognition in three listening conditions: high channel stimulation rate (ranging from 1500 to 2020 pps/ch), a medium rate (800 pps/ch) and a low rate (400 pps/ch). Number of channels was held constant across rate conditions. With the categorical identification task, performance varied by acoustic cue type but did not vary with rate. With the consonant recognition task performance varied by phonological feature, but there was also no significant effect of rate. However, two subjects showed markedly reduced sentence scores at lower rates. Results suggests that higher stimulation rates with the CIS strategy may be beneficial to speech perception in some cases.     

双侧人工耳蜗植入术后言语识别效果的评估

目的评估双侧人工耳蜗植入者汉语普通话短句、双音节词单音节词及汉语声调的识别效果,探索双侧人工耳蜗植入者双耳听觉产生的机制及对言语识别率的影响。方法选取双侧人工耳蜗植入患者6人,自制问卷收集受试者的基本信息并评估他们的主观听觉状况。首先测试受试者在使用双侧人工耳蜗（BCI）、单独使用一侧人工耳蜗（RCI/LCI）的听阈,随后测试他们在BCI和RCI/LCI两种听觉模式下的七音节短句、双音节词、声调、韵母、声母识别率,测试背景环境包括安静环境和嘈杂语噪声环境,言语信号强度为65dB SPL,固定信噪比为+10 dB SPL。随后将BCI和RCI/LCI两种听觉模式下的识别效果进行比较。结果除噪声状态下韵母识别测试中其余测试结果均为BCI言语识别率得分高于RCI/LCI。结论对于符合双侧人工耳蜗植入术适应证标准的患者而言,双侧植入人工耳蜗可以在不同程度上提高安静和噪声环境下的短句、双字词、声母、韵母及声调的识别率,降低其声场听阈。