Evaluative audiometry after cochlear implant provision.

BACKGROUND: One of the main treatment goals in cochlear implant (CI) patients is to improve speech perception. One of the target parameters is speech intelligibility in quiet. However, treatment results show a high variability, which has not been sufficiently explained so far. The aim of this noninterventional retrospective study was to elucidate this variability using a selected population of patients in whom etiology was not expected to have a negative impact on postoperative speech intelligibility. MATERIALS AND METHODS: Audiometric findings of the CI follow-up of 28 adult patients after 6 months of CI experience were evaluated. These were related to the preoperative audiometric examination and evaluated with respect to a recently published predictive model for the postoperative monosyllabic score. RESULTS: Inclusion of postoperative categorical loudness scaling and hearing loss for Freiburg numbers in the model explained 55% of the variability in fitting outcomes with respect to monosyllabic word recognition. CONCLUSION: The results of this study suggest that much of the cause of variability in fitting outcomes can be captured by systematic postoperative audiometric checks. Immediate conclusions for CI system fitting adjustments may be drawn from these results. However, the extent to which these are accepted by individual patients and thus lead to an improvement in outcome must be subject of further studies, preferably prospective.

Prediction of postoperative speech comprehension with the transcutaneous partially implantable bone conduction hearing system Osia®.

BACKGROUND: The active transcutaneous, partially implantable osseointegrated bone conduction system Cochlear™ Osia® (Cochlear, Sydney, Australia) has been approved for use in German-speaking countries since April 2021. The Osia is indicated for patients either having conductive (CHL) or mixed hearing loss (MHL) with an average bone conduction (BC) hearing loss of 55 dB HL or less, or having single-sided deafness (SSD). OBJECTIVES: The aim of this retrospective study was to investigate the prediction of postoperative speech recognition with Osia® and to evaluate the speech recognition of patients with MHL and in particular an aided dynamic range of less than 30 dB with Osia®. MATERIALS AND METHODS: Between 2017 and 2022, 29 adult patients were fitted with the Osia®, 10 patients (11 ears) with CHL and 19 patients (25 ears) with MHL. MHL was subdivided into two groups: MHL­I with four-frequency pure-tone average in BC (BC-4PTA) ≥ 20 dB HL and < 40 dB HL (n = 15 patients; 20 ears) vs. MHL-II with BC-4PTA ≥ 40 dB HL (n = 4 patients; 5 ears). All patients tested a bone conduction hearing device on a softband preoperatively. Speech intelligibility in quiet was assessed preoperatively using the Freiburg monosyllabic test in unaided condition, with the trial BCHD preoperatively and with Osia® postoperatively with Osia®. The maximum word recognition score (mWRS) unaided and the word recognition score (WRS) with the test system at 65 dB SPL were correlated with the postoperative WRS with Osia® at 65 dB SPL. RESULTS: Preoperative prediction of postoperative outcome with Osia® was better using the mWRS than by the WRS at 65 dB SPL with the test device on the softband. Postoperative WRS was most predictive for patients with CHL and less predictable for patients with mixed hearing loss with BC-4PTA ≥ 40 dB HL. For the test device on a softband, the achievable outcome tended to a minimum, with the mWRS tending to predict the realistically achievable outcome. CONCLUSION: Osia® can be used for the treatment of CHL and MHL within the indication limits. The average preoperative bone conduction hearing threshold also provides an approximate estimate of the postoperative WRS with Osia®, for which the most accurate prediction is obtained using the preoperative mWRS. Prediction accuracy decreases from a BC-4PTA of ≥ 40 dB HL.

Speech comprehension in noise-considerations for ecologically valid assessment of communication skills ability with cochlear implants.

BACKGROUND: Nowadays, cochlear implant (CI) patients mostly show good to very good speech comprehension in quiet, but there are known problems with communication in everyday noisy situations. There is thus a need for ecologically valid measurements of speech comprehension in real-life listening situations for hearing-impaired patients. The additional methodological effort must be balanced with clinical human and spatial resources. This study investigates possible simplifications of a complex measurement setup. METHODS: The study included 20 adults from long-term follow-up after CI fitting with postlingual onset of hearing impairment. The complexity of the investigated listening situations was influenced by changing the spatiality of the noise sources and the temporal characteristics of the noise. To compare different measurement setups, speech reception thresholds (SRT) were measured unilaterally with different CI processors and settings. Ten normal-hearing subjects served as reference. RESULTS: In a complex listening situation with four loudspeakers, differences in SRT from CI subjects to the control group of up to 8 dB were found. For CI subjects, this SRT correlated with the situation with frontal speech signal and fluctuating interference signal from the side with R2 = 0.69. For conditions with stationary interfering signals, R2 values <0.2 were found. CONCLUSION: There is no universal solution for all audiometric questions with respect to the spatiality and temporal characteristics of noise sources. In the investigated context, simplification of the complex spatial audiometric setting while using fluctuating competing signals was possible.

Validation of a predictive model for speech discrimination after cochlear impIant provision.

BACKGROUND: If sufficient speech discrimination is no longer achieved with conventional hearing systems, an audiological indication for a cochlear implant (CI) is given. However, there are no established target criteria for CI aftercare with regard to the level of speech comprehension to be achieved. The aim of this study is to validate an existing predictive model for speech comprehension after CI provision. This is applied to different patient groups. MATERIALS AND METHODS: The prospective study included 124 postlingually deaf adults. The model is based on preoperative maximum monosyllabic recognition score, aided monosyllabic recognition score at 65 dBSPL, and age the time of implantation. The model was investigated with regard to prediction accuracy for monosyllabic recognition with CI after 6 months. RESULTS: Mean speech discrimination improved from 10% with hearing aid to 65% with CI after 6 months, with a statistically significant improvement in 93% of cases. Deterioration of aided unilateral speech discrimination was not observed. The mean prediction error was 11.5 percentage points in the cases with preoperative scores better than zero and 23.2 percentage points in all other cases. CONCLUSION: Cochlear implantation should also be considered in patients with moderately severe to severe hearing loss and insufficient speech discrimination with hearing aids. The model based on preoperatively measured data for predicting speech discrimination with CI can be used in preoperative consultation and in the context of postoperative quality assurance.

[Validation of a predictive model for speech discrimination after cochlear implant provision]. / Validierung eines Modells zur Vorhersage des Sprachverstehens nach Cochleaimplantation.

BACKGROUND: If sufficient speech discrimination is no longer achieved with conventional hearing systems, an audiological indication for a cochlear implant (CI) is given. However, there are no established target criteria for CI aftercare with regard to the level of speech comprehension to be achieved. The aim of this study is to validate an existing predictive model for speech comprehension after CI provision. This is applied to different patient groups. MATERIALS AND METHODS: The prospective study included 124 postlingually deaf adults. The model is based on preoperative maximum monosyllabic recognition score, aided monosyllabic recognition score at 65 dBSPL, and age the time of implantation. The model was investigated with regard to prediction accuracy for monosyllabic recognition with CI after 6 months. RESULTS: Mean speech discrimination improved from 10% with hearing aid to 65% with CI after 6 months, with a statistically significant improvement in 93% of cases. Deterioration of aided unilateral speech discrimination was not observed. The mean prediction error was 11.5 percentage points in the cases with preoperative scores better than zero and 23.2 percentage points in all other cases. CONCLUSION: Cochlear implantation should also be considered in patients with moderately severe to severe hearing loss and insufficient speech discrimination with hearing aids. The model based on preoperatively measured data for predicting speech discrimination with CI can be used in preoperative consultation and in the context of postoperative quality assurance.

[Evaluative audiometry after cochlear implant provision. German Version]. / Zur evaluierenden Audiometrie nach Cochlea-Implantat-Versorgung.

BACKGROUND: One of the main treatment goals in cochlear implant (CI) patients is to improve speech perception. One of the target parameters is speech intelligibility in quiet. However, treatment results show a high variability, which has not been sufficiently explained so far. The aim of this noninterventional retrospective study was to elucidate this variability using a selected population of patients in whom etiology was not expected to have a negative impact on postoperative speech intelligibility. MATERIALS AND METHODS: Audiometric findings of the CI follow-up of 28 adult patients after 6 months of CI experience were evaluated. These were related to the preoperative audiometric examination and evaluated with respect to a recently published predictive model for the postoperative monosyllabic score. RESULTS: Inclusion of postoperative categorical loudness scaling and hearing loss for Freiburg numbers in the model explained 55% of the variability in fitting outcomes with respect to monosyllabic comprehension. CONCLUSION: The results of this study suggest that much of the cause of variability in fitting outcomes can be captured by systematic postoperative audiometric checks. Immediate conclusions for CI system adjustments may be drawn from these results. However, the extent to which these are accepted by individual patients and thus lead to an improvement in outcome must be subject to further study, preferably prospective.

[Prediction of speech understanding with the transcutaneous partially implantable bone conduction hearing system Osia®. German Version]. / Vorhersage des postoperativen Sprachverstehens mit dem transkutanen teilimplantierbaren Knochenleitungshörsystem Osia®.

BACKGROUND: The active transcutaneous, partially implantable osseointegrated bone conduction system Cochlear™ Osia® (Cochlear, Sydney, Australia) has been approved for use in German-speaking countries since April 2021. The Osia is indicated for patients with conductive (CHL) or mixed hearing loss (MHL) with an average bone conduction (BC) hearing loss of 55 dB or less, or with single-sided deafness (SSD). OBJECTIVES: The aim of this retrospective study was to investigate the prediction of postoperative speech recognition with Osia and to evaluate the speech recognition of patients with MHL and an aided dynamic range of less than 30 dB with Osia. MATERIALS AND METHODS: Between 2017 and 2022, 29 adult patients were fitted with the Osia, 10 patients (11 ears) with CHL and 19 patients (21 ears) with MHL. MHL was subdivided into two groups: MHL­I with four-frequency pure-tone average in BC (BC-4PTA) ≥ 20 dB HL and < 40 dB HL (n = 15 patients; 20 ears) vs. MHL-II with BC-4PTA ≥ 40 dB HL (n = 4 patients; 5 ears). All patients tested a bone conduction hearing device on a softband preoperatively. Speech intelligibility in quiet was assessed preoperatively using the Freiburg monosyllabic test unaided and with the test system and postoperatively with Osia. The maximum monosyllabic score (mEV) unaided and the monosyllabic score with the test system at 65 dB SPL were correlated with the postoperative monosyllabic score with Osia at 65 dB SPL. RESULTS: Preoperative prediction of postoperative outcome with Osia was better using the mEV than the EV at 65 dB SPL with the test device on the softband. Postoperative EV was most predictive for patients with CHL and least predictive for patients with mixed hearing loss with 4PTA BC ≥ 40 dB HL. For the test device at softband, results tended to show the minimum achievable outcome and the mEV tended to predict the realistically achievable outcome. CONCLUSION: Osia can be used for the treatment of CHL and MHL within the indication limits. The average preoperative bone conduction hearing threshold also provides an approximate estimate of the postoperative EV with Osia, for which the most accurate prediction is obtained using the preoperative mEV. Prediction accuracy decreases from a BC-4PTA of ≥ 40 dB.

[Speech comprehension in noise-considerations for ecologically valid assessment of communication skills ability with cochlear implants. German version]. / Sprachverstehen im Störschall ­ Überlegungen zur ökologisch validen Bewertung der Kommunikationsfähigkeit mit Cochleaimplantat.

BACKGROUND: Nowadays, cochlear implant (CI) patients mostly show good to very good speech comprehension in quiet, but there are known problems with communication in everyday noisy situations. There is thus a need for ecologically valid measurements of speech comprehension in real-life listening situations for hearing-impaired patients. The additional methodological effort must be balanced with clinical human and spatial resources. This study investigates possible simplifications of a complex measurement setup. METHODS: The study included 20 adults from long-term follow-up after CI fitting with postlingual onset of hearing impairment. The complexity of the investigated listening situations was influenced by changing the spatiality of the noise sources and the temporal characteristics of the noise. To compare different measurement setups, speech reception thresholds (SRT) were measured unilaterally with different CI processors and settings. Ten normal-hearing subjects served as reference. RESULTS: In a complex listening situation with four loudspeakers, differences in SRT from CI subjects to the control group of up to 8 dB were found. For CI subjects, this SRT correlated with the situation with frontal speech signal and fluctuating interference signal from the side with R2 = 0.69. For conditions with stationary interfering signals, R2 values <0.2 were found. CONCLUSION: There is no universal solution for all audiometric questions with respect to the spatiality and temporal characteristics of noise sources. In the investigated context, simplification of the complex spatial audiometric setting while using fluctuating competing signals was possible.

Evaluation of a synthetic version of the digits-in-noise test and its characteristics in CI recipients.

OBJECTIVE: The goal of this study was the evaluation of a synthetic version of the Digits-in-Noise (DiN) in participants with normal hearing. Additionally, the basis characteristics of the DiN in CI recipients were investigated. DESIGN AND STUDY SAMPLE: Twenty participants with normal hearing and 21 CI recipients with a Nucleus®-System ran two to three adaptive and up to five fixed measurements. Afterwards the discrimination function was measured with fixed signal-to-noise ratios. RESULTS: All subjects were able to perform the DiN within three minutes per test run. The median speech reception threshold (SRT) for the NH was -8.1 dBSNR, with a median steepness of 23%/dBSNR. The median absolute test-retest difference in the NH group was 0.4 dB (range: 0 to 1.5 dB). In the CI group, the SRTs range from -6.6 to +12.4 dBSNR with a median test-retest difference of 0.4 dB (range: 0 to 6.1 dB). CONCLUSION: The synthetic DiN is a valuable complement of the audiometric test battery in CI recipients. The excellent applicability is also particularly helpful in poor performing CI recipients. With its small time exposure, it is a time- and cost-saving test, which could also be used at home via app to check the individual hearing success.

ForwardFocus with cochlear implant recipients in spatially separated and fluctuating competing signals - introduction of a reference metric.

Objective: To clinically evaluate ForwardFocus in noise with experienced Nucleus® cochlear implant (CI) recipients.Design: Listening performance with ForwardFocus was compared against the best in class directional microphone program (BEAM®). Speech comprehension was tested with the Oldenburg sentence test with competing signals (stationary, three, six and 18-talker babble) in both co-located and spatially-separated listening environments. Additionally, normal hearing participants were tested monaurally in the same listening environments as a reference and to promote cross-study comparisons between CI clinical study outcomes.Study sample: Post-lingually deaf adult CI recipients (n = 20) who were experienced users of the Nucleus sound processor (Cochlear Limited).Results: Improved speech comprehension was found with the ForwardFocus program compared to the BEAM program in a co-located frontal listening environment for both stationary and fluctuating competing signals. In spatially-separated environments ForwardFocus provided significant speech reception threshold (SRT) improvements of 5.8 dB for three-talker competing signals, respectively.Conclusions: ForwardFocus was shown to significantly improve speech comprehension in a wide range of listening environments. This technology is likely to provide significant improvements in real-world listening for CI recipients, given the clinically relevant performance outcomes in challenging dynamic noise environments, bringing their performance closer to their normal hearing peers.

Maximum preimplantation monosyllabic score as predictor of cochlear implant outcome.

OBJECTIVE: This study investigated the speech perception of cochlear implant (CI) recipients with measurable preoperative ipsilateral speech perception. These data should support improved individual counselling of CI candidates. MATERIALS AND METHODS: Pre- and postoperative speech audiometric parameters were analyzed, including maximum score for phonemically balanced words (PBmax) and monosyllabic score at a normal conversational level of 65 dBSPL, with hearing aids one hand and CI on the other. Data of 284 experienced adult CI wearers were grouped and evaluated in terms of preoperative PBmax. RESULTS: The preoperative PBmax was exceeded by the postoperative monosyllabic score in 96% of cases. The overall median postoperative score was 72.5%. The groups with preoperative PBmax > 0% showed significantly better speech perception scores with CI than the group with PBmax = 0%. Median improvement compared to the preoperative monosyllabic score with hearing aids was 65 percentage points, independent of preoperative PBmax. CONCLUSION: The preoperatively measured PBmax may be used as a predictor for the minimum speech perception obtained with CI. This is of high clinical relevance for CI candidates with a PBmax above zero.

[Multicentric analysis of the use behavior of cochlear implant users]. / Multizentrische Analyse des Nutzerverhaltens von Cochlea-Implantat-Trägern.

INTRODUCTION: Novel cochlear implant speech processors are capable of storing data logs. With the help of this information a more individualized patient care can be provided. However, standard data are missing to a greater extent to the individual usage behavior. MATERIALS AND METHODS: In a retrospective study, the use data of 2687 patients were evaluated. All patients had the Nucleus 6 system from Cochlear Ltd. RESULTS: The data allow a normal range to be defined for the duration of use of cochlear implant speech processors. Likewise, the identification of conspicuous usage behavior is possible.

[Loudness optimized registration of compound action potential in cochlear implant recipients]. / Lautheitsoptimierte Messung von Summenaktionspotentialen bei Cochlea Implantat Trägern.

Background Postoperative measurements of compound action potentials are not always possible due to the insufficient acceptance of the CI-recipients. This study investigated the impact of different parameters on the acceptance of the measurements. Methods Compound action potentials of 16 CI recipients were measured with different pulse-widths. Recipients performed a loudness rating at the potential thresholds with the different sequences. Results Compound action potentials obtained with higher pulse-widths were rated softer than those obtained with smaller pulse-widths. Conclusions Compound action potentials measured with higher pulse-widths generate a gap between loudest acceptable presentation level and potential threshold. This gap contributes to a higher acceptance of postoperative measurements.

[Results of Speech Audiometry Testing in Case of Transcranial CROS Depend on Duration of Deafness]. / Audiologische Ergebnisse bei transkranieller CROS-Versorgung in Abhängigkeit von der Ertaubungsdauer.

In single sided deafness, treatment with transcranial CROS makes pseudo stereophonic listening possible. This leads to improved speech understanding in noise. However, several reports show large variations between the individual results of the benefit by speech audiometry in noise. One possible factor is the duration and changes in the auditory pathway between the onset of deafness to CROS supply. 18 patients with single sided deafness have tested a transcranial CROS supply. The speech intelligibility thresholds were evaluated in 2 spatial hearing situations each with CROS and unaided. When speech was arriving at 45° from the deaf ear and noise at 45° from the hearing ear, a significant improvement of speech reception threshold for 50% intelligibility was detected by CROS supply compared the medians. Patients with longer duration of deafness showed higher benefit by an average of -4.0 dB, in contrast to patients with short duration of deafness. In the reversed situation, that speech on the hearing ear and noise on the deaf ear was a significant deterioration observed, an average of 3.1 dB at longer deafened patients. In addition, a highly significant correlation was found with the individual changes in the speech recognition threshold between the two situations. The duration of deafness is an essential factor in the individual benefit estimate for treatment with transcranial CROS supply. The time frame for audimetrically proven changes in the auditory pathway as a result of unilateral auditory deprivation can be estimated to about 1-3 years. Patients with short duration of deafness have low or no benefit from transcranial CROS supply.

[Longterm Results of a Screening Procedure for Adult Cochlear Implant Candidates]. / Langzeitergebnisse eines Screeningverfahrens für erwachsene Cochlea-Implantat-Kandidaten.

This study gives an estimation of the long term outcome of a screening procedure for cochlear implant candidacy in hearing aid users.In a recent retrospective study, hearing aid performance and audiometric measures in 185 subjects (318 ears) were analyzed. In the context of 2 years follow-up, the outcome of the ipsilateral screening procedure was analyzed. For patients who did receive a cochlear implant, their audiometric outcome measures were viewed into relation to their preoperative results.From the 96 ears identified as cochlear implant candidates, 34 were provided with a cochlear implant. 222 ears were identified as hearing aid users. Only 4 of these 222 ears were provided with a cochlear implant. Cochlear implant recipients with a preoperative speech recognition score with hearing aids above zero showed a mean improvement of 65% points in Freiburg monosyllabics.The audiometry-based screening procedure enables an effective management of the referral process of cochlear implant candidates.

Speech Perception and Information-Carrying Capacity for Hearing Aid Users of Different Ages.

Hearing impairment in the elderly is usually treated with conventional hearing aids; however, a large number of older people do not achieve sufficient speech recognition with hearing aids. The aim of the study was to describe speech perception with hearing aids in comparison to pure-tone hearing loss and maximum speech recognition scores for phonemically balanced words. Data from 392 hearing aid users with different degrees of hearing loss were evaluated retrospectively. In particular, pure-tone thresholds, the maximum monosyllabic word score, and the monosyllabic word score in quiet at conversational level with a hearing aid were analysed. The results showed that speech perception scores decline with increasing age. Even when corrected for pure-tone hearing loss, a significant decline in speech recognition scores after the age of 80 years was observed. Regarding the maximum monosyllabic word score, the effect is smaller but still observable; thus, speech recognition with hearing aids is significantly lower for older subjects. This can be attributed partially to the reduction of the information-carrying capacity in this group.

A clinical assessment of cochlear implant recipient performance: implications for individualized map settings in specific environments.

Individual speech intelligibility was measured in quiet and noise for cochlear Implant recipients upgrading from the Freedom to the CP900 series sound processor. The postlingually deafened participants (n = 23) used either Nucleus CI24RE or CI512 cochlear implant, and currently wore a Freedom sound processor. A significant group mean improvement in speech intelligibility was found in quiet (Freiburg monosyllabic words at 50 dBSPL) and in noise (adaptive Oldenburger sentences in noise) for the two CP900 series SmartSound programs compared to the Freedom program. Further analysis was carried out on individual's speech intelligibility outcomes in quiet and in noise. Results showed a significant improvement or decrement for some recipients when upgrading to the new programs. To further increase speech intelligibility outcomes when upgrading, an enhanced upgrade procedure is proposed that includes additional testing with different signal-processing schemes. Implications of this research are that future automated scene analysis and switching technologies could provide additional performance improvements by introducing individualized scene-dependent settings.

Intraoperative findings on ECAP-measurement: normal or special case?

OBJECTIVE: This study aimed to investigate the measurability and threshold level of electrically evoked compound action potentials (ECAPs) in order to provide a baseline for the development of diagnostic references to support aftercare procedures. DESIGN: In this retrospective study, cochlear implant patients were grouped according to the electrode array type and preoperative diagnostic findings from radiological imaging. ECAP measurements were performed intraoperatively on 22 electrodes for each patient resulting in two comparisons: (1) normal vs. pathological findings based on imaging with same electrode array, (2) perimodiolar electrode vs. straight electrode array within the normal group. STUDY SAMPLE: The study sample consisted of 218 ears with a Nucleus(®) implant. RESULTS: In the group with normal radiological imaging, the percentage of measurable ECAPs was higher than in the pathological group. The ECAP thresholds on 21 electrodes were significantly different between the two groups. Furthermore the thresholds were significantly lower for basal electrodes mainly for the two different electrode types. CONCLUSION: The pathological changes in the inner ear, the type of electrode array, and the electrode position affect the ECAP threshold. Further consideration suggests that a receiver operating characteristic curve can be derived from the results.

Investigation of a matrix sentence test in noise: reproducibility and discrimination function in cochlear implant patients.

OBJECTIVE: The aim of this study was to describe common properties (reproducibility, discrimination function, and its steepness) of matrix tests used for cochlear implant (CI) users and to obtain data for the German-language version matrix test, the Oldenburg sentence test (OLSA), presented in noise. DESIGN: The speech reception thresholds (SRT) in noise were measured by means of an adaptive test procedure, and by measurement at various signal-to-noise ratios to determine the course of the entire discrimination function per subject. STUDY SAMPLE: The measurements were performed on 38 CI users fitted with a Cochlear(™) Freedom(®) or a Cochlear(™) Nucleus(®) 5 CI system. RESULTS: The test-retest reproducibility showed a significant dependence on the SRT in noise. For the better performers, the test-retest difference was found to be smaller, while for the poorer performers the difference increased. For the better performers, the slope of the discrimination function at SRT (s50) was comparable to that for individuals with normal hearing, while for the poorer performers the s50 tended to be significantly reduced. CONCLUSIONS: As the CI users differed significantly in their SRT and their s50, a unified discrimination function for CI users must not be used. Further tailoring of the procedure may be required, especially for poorer CI performers.