Griet Mertens

Tinnitus in a single-sided deaf ear reduces speech reception in the nontinnitus ear.

Background The influence of tinnitus on speech reception is under debate. A few previous studies addressed this issue and compared speech reception in groups with and without tinnitus, with tinnitus arising in both ears or in the same test ear. Recently, we demonstrated that loudness of tinnitus in single-sided deafness (SSD) could be reduced dramatically by implanting and activating a cochlear implant (CI). Purpose The aim of the study was to evaluate whether changing the level of tinnitus in the SSD ear by disenabling or enabling the CI changes the speech reception in noise in the non-tinnitus ear. Methods and Patients Fifteen CI users (MED-EL multichannel) with SSD and incapacitating tinnitus participated. They had an initial score of 6 or greater out of 10 on the Visual Analogue Scale (VAS) and an average total score of 58.05 (standard deviation [SD], 13.68) on the Tinnitus Questionnaire. The outcome measure, speech reception threshold (SRT) in noise using an adaptive procedure was measured in the nontinnitus ear using insert earphones. The measurements were performed with a high tinnitus level and a low tinnitus level in the SSD ear, realized by switching the CI off or on. Tinnitus loudness was assessed on a VAS, and tinnitus loudness was also matched using an audiometer. Results Speech reception in noise is significantly worse in case of high tinnitus loudness. The mean difference in SRT in the nontinnitus ear between the 2 conditions (SRTCI off–SRTCI on) of the 15 subjects was 1.98 dB SNR (SD, 3.01 dB SNR). The mean tinnitus loudness on the VAS was 7.2 (SD, 2.6) in the CI-off condition. In the CI-on condition, the mean VAS score significantly declined to 3.4 (SD, 2.5). Also, the tinnitus loudness match improved from 22 dB SL (SD, 14.4 dB SL) to 10 dB SL (SD, 10.1 dB SL) in the CI-on condition. Conclusion Unilateral tinnitus can significantly decrease speech reception in noise in the nontinnitus ear.

Binaural auditory outcomes in patients with postlingual profound unilateral hearing loss: 3 years after cochlear implantation.

The value of cochlear implants (CI) in patients with profound unilateral hearing loss (UHL) and tinnitus has recently been investigated. The authors previously demonstrated the feasibility of CI in a 12- month outcome study in a prospective UHL cohort. The aim of this study was to investigate the binaural auditory outcomes in this cohort 36 months after CI surgery. The 36-month outcome was evaluated in 22 CI users with postlingual UHL and severe tinnitus. Twelve subjects had contralateral normal hearing (single-sided deafness - SSD group) and 10 subjects had a contralateral, mild to moderate hearing loss and used a hearing aid (asymmetric hearing loss - AHL group). Speech perception in noise was assessed in two listening conditions: the CIoff and the CIon condition. The binaural summation effect (S₀N₀), binaural squelch effect (S₀NCI) and the combined head shadow effect (SCIN₀) were investigated. Subjective benefit in daily life was assessed by means of the Speech, Spatial and Qualities of Hearing Scale (SSQ). At 36 months, a significant binaural summation effect was observed for the study cohort (2.00, SD 3.82 dB; p < 0.01) and for the AHL subgroup (3.34, SD 5.31 dB; p < 0.05). This binaural effect was not significant 12 months after CI surgery. A binaural squelch effect was significant for the AHL subgroup at 12 months (2.00, SD 4.38 dB; p < 0.05). A significant combined head shadow and squelch effect was also noted in the spatial configuration SCIN₀ for the study cohort (4.00, SD 5.89 dB; p < 0.01) and for the AHL subgroup (5.67, SD 6.66 dB; p < 0.05). The SSQ data show that the perceived benefit in daily life after CI surgery remains stable up to 36 months at CIon. CI can significantly improve speech perception in noise in patients with UHL. The positive effects of CIon speech perception in noise increase over time up to 36 months after CI surgery. Improved subjective benefit in daily life was also shown to be sustained in these patients.

Prospective case-controlled sound localisation study after cochlear implantation in adults with single-sided deafness and ipsilateral tinnitus.

To analyse the sound localisation skills of subjects with profound single‐sided deafness (SSD) and accompanied ipsilateral tinnitus who are using a cochlear implant (CI) for between 4 and 11 years.

Perceptual changes in place of stimulation with long cochlear implant electrode arrays

Long (31.5 mm) electrode arrays are inserted deeper into the cochlea than the typical 1.25 turn insertion. With these electrode arrays, the apical electrodes are closer to (and possibly extend past) the end of the spiral ganglion. Using multi-dimensional scaling with patients implanted with a 31.5 mm electrode array, the perceptual space between electrodes was measured. The results suggest that deeper insertion increases the range of place pitches, but the perceptual differences between adjacent electrodes become smaller in the apex.

Hearing performance in single-sided deaf cochlear implant users after upgrade to a single-unit speech processor

Introduction Single-sided deaf (SSD) patients report multiple benefits after cochlear implantation (CI), such as tinnitus suppression, speech perception, and sound localization. The first single-unit speech processor, the RONDO, was launched recently. Both the RONDO and the well-known behind-the-ear (BTE) speech processor work on the same audio processor platform. However, in contrast to the BTE, the microphone placement on the RONDO is different. The aim of this study was to evaluate the hearing performances using the BTE speech processor versus using the single-unit speech processor. Subjective and objective outcomes in SSD CI patients with a BTE speech processor and a single-unit speech processor, with particular focus on spatial hearing, were compared. Methodology Ten adults with unilateral incapacitating tinnitus resulting from ipsilateral sensorineural deafness were enrolled in the study. The mean age at enrollment in the study was 56 (standard deviation, 13) years. The subjects were cochlear implanted at a mean age of 48 (standard deviation, 14) years and had on average 8 years’ experience with their CI (range, 4–11 yr). At the first test interval (T0), testing was conducted using the subject’s BTE speech processor, with which they were already familiar. Aided free-field audiometry, speech reception in noise, and sound localization testing were performed. Self-administered questionnaires on subjective evaluation consisted of HISQUI-NL, SSQ5, SHQ, and a Visual Analogue Scale to assess tinnitus loudness and disturbance. All 10 subjects were upgraded to the single-unit processor and retested after 28 days (T28) with the same fitting map. At T28, an additional single-unit questionnaire was administered to determine qualitative experiences and the effect of the position of the microphone on the new speech processor. Results Equal hearing outcomes were found between the single-unit speech processor: median PTAsingle-unit (0.5, 1, 2 kHz) = 40 (range, 33–48) dB HL; median Speech Reception Threshold in noise = −1.00 (range, −8.50 to +1.00) dB SNR; median Root Mean Square Error of sound localization = 45 (range, 19–139) degrees; HISQUI = 128 (range, 106–180); SHQ = 68 (range, 45–83); SSQ5 = 6 (range, 3–9) and the BTE speech processor: median PTABTE (0.5, 1, 2 kHz) = 41 (range, 30–53) dB HL; median Speech Reception Threshold in noise = −0.25 (range, −7.00 to +4.00) dB SNR; median Root Mean Square Error of sound localization = 38 (range, 26–164) degrees; HISQUI = 144 (range, 120–183); SHQ = 56 (range, 47–85); SSQ5 = 6 (range, 3–9). The results in the condition with the single-unit speech processor were not significantly influenced by the position of the microphone. Conclusion The study showed that long-term BTE speech processor SSD users are able to be upgraded to a single-unit speech processor without compromising their speech performance, aided hearing thresholds, sound localization, objective speech quality, hearing abilities, sound localization, and tinnitus reduction. Microphone position on the single-unit speech processor did not influence the outcomes measures. Moreover, after a short time of experience, 80% of the users preferred the single-unit processor.

An experimental objective method to determine maximum output and dynamic range of an active bone conduction implant: the Bonebridge

Introduction Recently, a new active bone conduction implant, the Bonebridge, was introduced. This transcutaneous device is proposed as an alternative to previous percutaneous systems. The current study aims to determine the maximum output (MO) of the Bonebridge by making use of Bonebridge-generated sound pressure levels in the occluded ear canal of the unaided ear. Methodology The test setup consisted of audiometry and input-output measurements. These tests were performed on 3 Bonebridge users with conductive or mixed hearing loss (bone-conduction thresholds, ⩽45 dB HL) at least 3 months after implantation surgery. All the patients were implanted and were evaluated in the Antwerp University Hospital. The MO of the device was determined by measuring input-output functions with a microphone placed in the occluded contralateral ear canal using the Aurical REM system. During testing, the sound processor was fitted in linear amplification mode and with unlimited output to determine the MO and the input dynamic range of the Bonebridge. This experimental setup intends to evaluate the device in a fitting program without compression. Results The mean MO of the device was 55 dB HL (SD, 6 dB HL) at 0.5 kHz, 61 dB HL (SD, 18 dB HL), 71 dB HL (SD, 10 dB HL) at 2 kHz, and 60 dB HL (SD, 10 dB HL) at 4 kHz. The mean dynamic range of the Bonebridge was 41 (SD, 5) dB HL, 46 (SD, 10) dB HL, 46 (SD, 5) dB HL, and 37 (SD, 16) dB HL for 0.5, 1, 2, and 4 kHz, respectively. Conclusion In summary, ear canal measures can effectively be used to assess input-output behavior of the Bonebridge. The present study indicates that the MO of the Bonebridge ranges from 55 to 71 dB HL, depending on frequency. Accepting a minimum dynamic range of 35 dB with the Bonebridge, fitting of the Bonebridge in a linear program is advocated in patients with a sensorineural hearing loss component of up to 30 dB HL.

Self-assessment of hearing disabilities in cochlear implant users using the SSQ and the reduced SSQ5 version.

Objectives Routine clinical assessment to evaluate the hearing performance in a cochlear implant (CI) population should include individual self-assessment tools. Because of pragmatic and psychometric considerations, there’s a growing need for reduced self-assessment questionnaires. The aim of the study is twofold. First, the study aims to ascertain a disability profile, using the Speech, Spatial and Qualities of Hearing Scale (SSQ), in a CI population and to compare this profile with a hearing impaired group with similar average hearing thresholds. The second aim of the study is to investigate the degree of agreement between the total SSQ scores and the total scores of the reduced 5-item version of the SSQ, namely, the SSQ5. Methods and Subjects This cross-sectional study uses the SSQ obtained from CI patients from the Ear, Nose and Throat (ENT) department of the Antwerp University Hospital. Fifty-four postlingually deaf CI patients completed the SSQ questionnaire. All subjects were implanted with a CI at an average age of 55 years. At the time they completed the questionnaire, they had, on average, 3 (SD, 3) years of CI experience. To determine the disability profile in a CI population, the following criteria were assayed: standard values, internal consistency, sensitivity, and floor (or ceiling) effects of the SSQ. These criteria were compared with those of a hearing-impaired group (n = 153) reported in the original study. Second, Spearman correlations coefficients and intraclass correlations coefficients (ICCs) were used to determine the degree of agreement between the total SSQ scores and the total SSQ5 scores. Results Analysis of internal consistency, sensitivity, and floor and ceiling effects showed that self-assessment using the SSQ is feasible in a CI population. The obtained disability profile presents a mean total SSQ C I group of 4:25 ( S D = 1:65). When comparing item results, significant differences were found between CI users and moderate hearing-impaired patients (SSQ hearing impaired group = 5.5; S D1:9). Intraclass correlation (ICC = 0.78; p < 0.01) and Spearman correlations coefficients (R = 0.77; p < 0.01) indicate a significantly high degree of agreement between the total SSQ scores and the total SSQ5 scores. Conclusion This article shows the disability profile in a CI population, using SSQ. Significant differences regarding dynamic aspects of hearing between CI users and moderate hearing-impaired patients were found, to the detriment of the CI users. The static aspects of hearing represented in the Speech section, on the other hand, showed more similarities. The reduced 5-item version of the SSQ, namely, the SSQ5, is robust to effectively measure evolutions in hearing (dis)abilities in CI users.

Evaluation of Long-Term Cochlear Implant Use in Subjects With Acquired Unilateral Profound Hearing Loss: Focus on Binaural Auditory Outcomes.

Introduction: Cochlear implantation (CI) in subjects with unilateral profound sensorineural hearing loss was investigated. The authors of the present study demonstrated the binaural auditory outcomes in a 12- and 36-month prospective cohort outcome study. The present study aimed to do a long-term (LT) evaluation of the auditory outcomes in an analogous study group. Design: LT evaluation was derived from 12 single-sided deaf (SSD) CI recipients and from 11 CI recipients with asymmetric hearing loss (AHL). A structured interview was conducted with each subjects. Speech perception in noise and sound localization were assessed in a CIOFF and in a CION condition. Four binaural effects were calculated: summation effect (S0N0), squelch effect (S0NCI), combined head shadow effect (SCIN0), and spatial release from masking (SRM). At the LT evaluation, the contribution of a CI or a bone conduction device on speech perception in noise was investigated in two challenging spatial configurations in the SSD group. Results: All (23/23) subjects wore their CI 7 days a week at LT follow-up evaluation, which ranged from 3 to 10 years after implantation. In the SSD group, a significant combined head shadow effect of 3.17 dB and an SRM benefit of 4.33 dB were found. In the AHL group, on the other hand, the summation effect (2.00 dB), the squelch effect (2.67 dB), the combined head shadow effect (3.67 dB), and SRM benefit (2.00 dB) were significant at LT testing. In both the spatial challenging configurations, the speech in noise results was significantly worse in the condition with the bone conduction device compared with the unaided condition. No negative effect was found for the CION condition. A significant benefit in the CION condition was found for sound localization compared with the CIOFF condition in the SSD group and in the AHL group. Conclusion: All subjects wore their CI 7 days a week at LT follow-up evaluation. The presence of binaural effects has been demonstrated with speech in noise testing, sound localization, and subjective evaluation. In the AHL group, all investigated binaural effects were found to be significant. In the SSD group on the other hand, only SRM and the head shadow, the two most robust binaural effects, were significantly present. However, it took 12M before the SSD and the AHL subjects significantly benefit from the head shadow effect. These reported results could guide counseling of future CI candidates with SSD and AHL in general.

A novel method for device-related electroencephalography artifact suppression to explore cochlear implant-related cortical changes in single-sided deafness

BACKGROUND Quantitative electroencephalography (qEEG) is effective when used to analyze ongoing cortical oscillations in cochlear implant (CI) users. However, localization of cortical activity in such users via qEEG is confounded by the presence of artifacts produced by the device itself. Typically, independent component analysis (ICA) is used to remove CI artifacts in auditory evoked EEG signals collected upon brief stimulation and it is effective for auditory evoked potentials (AEPs). However, AEPs do not reflect the daily environments of patients, and thus, continuous EEG data that are closer to such environments are desirable. In this case, device-related artifacts in EEG data are difficult to remove selectively via ICA due to over-completion of EEG data removal in the absence of preprocessing. NEW METHODS EEGs were recorded for a long time under conditions of continuous auditory stimulation. To obviate the over-completion problem, we limited the frequency of CI artifacts to a significant characteristic peak and apply ICA artifact removal. RESULTS Topographic brain mapping results analyzed via band-limited (BL)-ICA exhibited a better energy distribution, matched to the CI location, than data obtained using conventional ICA. Also, source localization data verified that BL-ICA effectively removed CI artifacts. COMPARISON WITH EXISTING METHOD The proposed method selectively removes CI artifacts from continuous EEG recordings, while ICA removal method shows residual peak and removes important brain activity signals. CONCLUSION CI artifacts in EEG data obtained during continuous passive listening can be effectively removed with the aid of BL-ICA, opening up new EEG research possibilities in subjects with CIs.

Sound quality in adult cochlear implant recipients using the HISQUI19.

Abstract Conclusion: On average, adult CI recipients report a moderate sound quality using the Dutch version of the HISQUI19 questionnaire. These results are correlated with their age, speech perception scores, CI aided hearing thresholds, and the SSQ5 and the APHAB questionnaire. Background: The general aim of the study was to assess sound quality in adult cochlear implant (CI) recipients and to link these findings to other patients reported outcome measures (PROM) and subject characteristics. Therefore, the Hearing Implant Sound Quality Index (HISQUI19), which was translated into Dutch, was used. This user-friendly instrument quantifies sound quality experienced by hearing implant users. Methods: The Dutch version of the original German HISQUI19 was obtained by the process of translation and back-translation. The HISQUI19 was assessed in 65 experienced adult CI users at the Ear, Nose, and Throat (ENT) department of the Antwerp University Hospital to assess a sound quality profile of experiences adult CI recipients. Therefore, descriptive statistics were used to summarize the mean, standard deviation, and ceiling or floor effects of the total HISQUI19 scores in a CI population. Spearman correlations between the HISQUI19 scores and objective audiological measures and other PROM were investigated (APHAB and SSQ5 questionnaire). Results: The mean HISQUI19 score of the Dutch version in adult CI recipients was 64.9 (SD = 20.8), which corresponds to moderate sound quality. The psychometric characters of the Dutch questionnaire are similar to the characters of the original HISQUI19 questionnaire, emphasizing good internal consistency (α = 0.93) and construct validity. Moderate correlation was found with speech perception in quiet (r = 0.36, p < 0.01), speech perception in noise (r = 0.29, p < 0.05), CI aided Pure Tone Average (PTA0.5, 1, 2 and 4 kHz) of the subjects (r = 0.34, p < 0.01), and the age of the subject (r = 0.38, p < 0.01). Gender did not influence the experienced sound quality significantly. Furthermore, the relation to other questionnaires was found to be significantly strong (SSQ5: r = 0.68 and the APHAB: r = 0.64; p < 0.01).