Sound Localization in Single-Sided Deafness; Outcomes of a Randomized Controlled Trial on the Comparison Between Cochlear Implantation, Bone Conduction Devices, and Contralateral Routing of Signals Hearing Aids.

There is currently a lack of prospective studies comparing multiple treatment options for single-sided deafness (SSD) in terms of long-term sound localization outcomes. This randomized controlled trial (RCT) aims to compare the objective and subjective sound localization abilities of SSD patients treated with a cochlear implant (CI), a bone conduction device (BCD), a contralateral routing of signals (CROS) hearing aid, or no treatment after two years of follow-up. About 120 eligible patients were randomized to cochlear implantation or to a trial period with first a BCD on a headband, then a CROS (or vice versa). After the trial periods, participants opted for a surgically implanted BCD, a CROS, or no treatment. Sound localization accuracy (in three configurations, calculated as percentage correct and root-mean squared error in degrees) and subjective spatial hearing (subscale of the Speech, Spatial and Qualities of hearing (SSQ) questionnaire) were assessed at baseline and after 24 months of follow-up. At the start of follow-up, 28 participants were implanted with a CI, 25 with a BCD, 34 chose a CROS, and 26 opted for no treatment. Participants in the CI group showed better sound localization accuracy and subjective spatial hearing compared to participants in the BCD, CROS, and no-treatment groups at 24 months. Participants in the CI and CROS groups showed improved subjective spatial hearing at 24 months compared to baseline. To conclude, CI outperformed the BCD, CROS, and no-treatment groups in terms of sound localization accuracy and subjective spatial hearing in SSD patients. TRIAL REGISTRATION Netherlands Trial Register (https://onderzoekmetmensen.nl): NL4457, CINGLE trial.

Tinnitus reduction in patients with single-sided deafness: the effect of cochlear implantation, bone conduction devices, and contralateral routing of sound hearing aids investigated in a randomized controlled trial.

Objectives: Single-sided deafness (SSD) is often accompanied by tinnitus, resulting in a decreased quality of life. Currently, there is a lack of high level of evidence studies comparing different treatment options for SSD regarding tinnitus reduction. This randomized controlled trial (RCT) evaluated the effect of a cochlear implant (CI), bone conduction device (BCD), contralateral routing of sound (CROS), and no treatment on tinnitus outcomes in SSD patients, with follow-up extending to 24 months. Methods: A total of 120 adult SSD patients were randomized to three groups: CI, a trial period with first a BCD on a headband, then a CROS, or vice versa. After the trial periods, patients opted for a BCD, CROS, or no treatment. At the start of follow-up, 28 patients were implanted with a CI, 25 patients with a BCD, 34 patients had a CROS, and 26 patients chose no treatment. The Tinnitus Handicap Inventory (THI), Tinnitus Questionnaire (TQ), the Visual Analog Scale (VAS), and the Hospital Anxiety and Depression Scale (HADS) were completed at baseline and at 3, 6, 12, and 24 months of follow-up. Results: The CI and BCD groups showed significantly decreased tinnitus impact scores. The CI group showed the largest decrease, which was already observed at 3 months of follow-up. Compared to the baseline, the median THI score decreased by 23 points, the TQ score by 17 points, and the VAS score by 60 points at 24 months. In the BCD group, the TQ score decreased by 9 points, and the VAS decreased by 25 points at 24 months. The HADS anxiety and depression subscale showed no indication for anxiety or depression at baseline, nor at 24 months, for all groups. Conclusion: In this RCT, SSD patients treated with a CI or BCD showed an overall decrease in tinnitus impact scores up to 24 months compared to baseline. The CI group reported a stable and the largest reduction. Cochlear implants appear to be superior to BCD and CROS, and no treatment for achieving partial or complete resolution of tinnitus in patients with SSD. Clinical trial registration: Netherlands Trial Register, www.onderzoekmetmensen.nl/nl/trial/26952, NTR4457, CINGLE trial.

Choice of treatment evaluated after trial periods with bone conduction devices and contralateral routing of sound systems in patients with single-sided deafness.

Objectives: Patients with single-sided deafness (SSD) may experience difficulties with speech perception in noise, sound localization, have tinnitus and experience a reduced quality of life (QoL). contralateral routing of sound hearing aids (CROS) or bone conduction devices (BCD) may partly improve subjective speech communication and QoL in SSD patients. A trial period with these devices can help in making a well-informed choice of treatment. Our aim was to evaluate factors influencing the choice of treatment made after a BCD and CROS trial period in adult SSD patients. Methods: Patients were randomized in the: "first BCD, then CROS" or "first CROS, then BCD" trial period group. After the BCD on headband and CROS were tested for 6 weeks each, patients choose for BCD, CROS or no treatment. Primary outcome was the distribution of choice of treatment. Secondary outcomes included the association between the choice of treatment and patient characteristics, reasons for treatment acceptance or rejection, device usage during the trial periods, and disease-specific QoL outcomes. Results: Of 91 patients randomized, 84 completed both trial periods and made their choice of treatment: 25 (30%) BCD, 34 (40%) CROS, and 25 (30%) no treatment. No characteristics were found to be related to choice of treatment. Top three reasons for acceptance or rejection were: device (dis)comfort, sound quality and (dis)advantage of subjective hearing. Average daily device use during the trial periods was higher for CROS than for BCD. Choice of treatment was significantly related with both duration of device usage and greater improvement of QoL after the corresponding trial period. Conclusion: The majority of SSD patients preferred BCD or CROS over no treatment. Evaluating device usage, discussing treatment (dis)advantages and disease-specific QoL outcomes after trial periods are to be considered during patient counseling and could facilitate whether to choose one of these treatments. Level of evidence: 1B.

The Acoustic Change Complex Compared to Hearing Performance in Unilaterally and Bilaterally Deaf Cochlear Implant Users.

OBJECTIVES: Clinical measures evaluating hearing performance in cochlear implant (CI) users depend on attention and linguistic skills, which limits the evaluation of auditory perception in some patients. The acoustic change complex (ACC), a cortical auditory evoked potential to a sound change, might yield useful objective measures to assess hearing performance and could provide insight in cortical auditory processing. The aim of this study is to examine the ACC in response to frequency changes as an objective measure for hearing performance in CI users. DESIGN: Thirteen bilaterally deaf and six single-sided deaf subjects were included, all having used a unilateral CI for at least 1 year. Speech perception was tested with a consonant-vowel-consonant test (+10 dB signal-to-noise ratio) and a digits-in-noise test. Frequency discrimination thresholds were measured at two reference frequencies, using a 3-interval, 2-alternative forced-choice, adaptive staircase procedure. The two reference frequencies were selected using each participant's frequency allocation table and were centered in the frequency band of an electrode that included 500 or 2000 Hz, corresponding to the apical electrode or the middle electrode, respectively. The ACC was evoked with pure tones of the same two reference frequencies with varying frequency increases: within the frequency band of the middle or the apical electrode (+0.25 electrode step), and steps to the center frequency of the first (+1), second (+2), and third (+3) adjacent electrodes. RESULTS: Reproducible ACCs were recorded in 17 out of 19 subjects. Most successful recordings were obtained with the largest frequency change (+3 electrode step). Larger frequency changes resulted in shorter N1 latencies and larger N1-P2 amplitudes. In both unilaterally and bilaterally deaf subjects, the N1 latency and N1-P2 amplitude of the CI ears correlated to speech perception as well as frequency discrimination, that is, short latencies and large amplitudes were indicative of better speech perception and better frequency discrimination. No significant differences in ACC latencies or amplitudes were found between the CI ears of the unilaterally and bilaterally deaf subjects, but the CI ears of the unilaterally deaf subjects showed substantially longer latencies and smaller amplitudes than their contralateral normal-hearing ears. CONCLUSIONS: The ACC latency and amplitude evoked by tone frequency changes correlate well to frequency discrimination and speech perception capabilities of CI users. For patients unable to reliably perform behavioral tasks, the ACC could be of added value in assessing hearing performance.

Cortical potentials evoked by tone frequency changes can predict speech perception in noise.

Accurate and objective assessment of higher order auditory processing is challenging and mainly relies on evaluations that require a subjects' active participation in tests such as frequency discrimination or speech perception in noise. This study investigates the value of cortical auditory evoked potentials (CAEPs) evoked in response to auditory change stimuli, known as acoustic change complexes (ACCs), as an objective measurement of auditory performance in hearing impairment. Secondary objectives were to assess the effect of hearing loss and non-professional musical experience on the ACC, and compare the ACC to the 'conventional' CAEP evoked in response to stimulus onset. In 24 normal-hearing subjects, consisting of 12 musicians and 12 non-musicians, and 13 age-matched hearing-impaired subjects ACCs were recorded in response to 12% frequency increases at four base frequencies (0.5, 1, 2 and 4 kHz). ACC amplitudes and latencies were compared to frequency discrimination thresholds at each base frequency, and to speech perception in noise. Frequency discrimination and speech perception in noise were significantly better for larger ACC N1-P2 amplitudes and shorter N1 latencies, whereas both frequency discrimination and speech perception did not correlate with onset CAEP amplitude or latency. Multiple regression analysis for prediction of speech perception in noise revealed that the strongest model was obtained by averaging over three frequencies (1, 2 and 4 kHz) with two significant predictors: hearing loss (R2 = 0.52) and ACC latency (R2 = 0.35). Thus, explaining 87% of the variance, this model indicates that subjects with longer ACC latencies have worse speech perception in noise than subjects with comparable hearing thresholds and shorter ACC latencies. If hearing loss was removed from this model, the combination of ACC amplitude and latency over those three frequencies explained 74% of the total variance in speech perception in noise. There were no differences in frequency discrimination, speech perception, CAEP, or ACC between recreational musicians and non-musicians. We conclude that the objective ACC N1 latency is a good predictor of speech perception in noise. When confirmed in validation studies with larger numbers of subjects, it can aid clinicians in their evaluation of auditory performance and higher order processing, in particular when behavioral testing is unreliable.

Short-term outcomes of cochlear implantation for single-sided deafness compared to bone conduction devices and contralateral routing of sound hearing aids-Results of a Randomised controlled trial (CINGLE-trial).

Single-sided deafness (SSD) leads to difficulties with speech perception in noise, sound localisation, and sometimes tinnitus. Current treatments (Contralateral Routing of Sound hearing aids (CROS) and Bone Conduction Devices (BCD)) do not sufficiently overcome these problems. Cochlear implants (CIs) may help. Our aim was to evaluate these treatments in a Randomised Controlled Trial (RCT). Adult SSD patients were randomised using a web-based randomisation tool into one of three groups: CI; trial period of 'first BCD, then CROS'; trial period of 'first CROS, then BCD'. After these trial periods, patients opted for BCD, CROS, or No treatment. The primary outcome was speech perception in noise (directed from the front (S0N0)). Secondary outcomes were speech perception in noise with speech directed to the poor ear and noise to the better ear (SpeNbe) and vice versa (SbeNpe), sound localisation, tinnitus burden, and disease-specific quality of life (QoL). We described results at baseline (unaided situation) and 3 and 6 months after device activation. 120 patients were randomised. Seven patients did not receive the allocated intervention. The number of patients per group after allocation was: CI (n = 28), BCD (n = 25), CROS (n = 34), and No treatment (n = 26). In S0N0, the CI group performed significantly better when compared to baseline, and when compared to the other groups. In SpeNbe, there was an advantage for all treatment groups compared to baseline. However, in SbeNpe, BCD and CROS groups performed worse compared to baseline, whereas the CI group improved. Only in the CI group sound localisation improved and tinnitus burden decreased. In general, all treatment groups improved on disease-specific QoL compared to baseline. This RCT demonstrates that cochlear implantation for SSD leads to improved speech perception in noise, sound localisation, tinnitus burden, and QoL after 3 and 6 months of follow-up. For most outcome measures, CI outperformed BCD and CROS. Trial registration: Netherlands Trial Register (www.trialregister.nl): NTR4580, CINGLE-trial.

Spin in Published Reports of Tinnitus Randomized Controlled Trials: Evidence of Overinterpretation of Results.

Background: Spin refers to reporting practices that could distort the interpretation and mislead readers by being more optimistic than the results justify, thereby possibly changing the perception of clinicians and influence their decisions. Because of the clinical importance of accurate interpretation of results and the evidence of spin in other research fields, we aim to identify the nature and frequency of spin in published reports of tinnitus randomized controlled trials (RCTs) and to assess possible determinants and effects of spin. Methods: We searched PubMed systematically for RCTs with tinnitus-related outcomes published from 2015 to 2019. All eligible articles were assessed on actual and potential spin using prespecified criteria. Results: Our search identified 628 studies, of which 87 were eligible for evaluation. A total of 95% of the studies contained actual or potential spin. Actual spin was found mostly in the conclusion of articles, which reflected something else than the reported point estimate (or CI) of the outcome (n = 34, 39%) or which was selectively focused (n = 49, 56%). Linguistic spin ("trend," "marginally significant," or "tendency toward an effect") was found in 17% of the studies. We were not able to assess the association between study characteristics and the occurrence of spin due to the low number of trials for some categories of the study characteristics. We found no effect of spin on type of journal [odds ratio (OR) -0.13, 95% CI -0.56-0.31], journal impact factor (OR 0.17, 95% CI -0.18-0.51), or number of citations (OR 1.95, CI -2.74-6.65). Conclusion: There is a large amount of spin in tinnitus RCTs. Our findings show that there is room for improvement in reporting and interpretation of results. Awareness of different forms of spin must be raised to improve research quality and reduce research waste.

Selective Reporting of Outcomes in Tinnitus Trials: Comparison of Trial Registries With Corresponding Publications.

Objectives: We aimed to study the prevalence of selective reporting of primary and secondary outcomes in tinnitus trials and to examine if selective reporting of outcome measures is influenced by the nature and direction of its results. Background: Selective reporting of outcome measures has been reported in several biomedical fields and can influence the clinical usefulness and implementation of outcomes of clinical trials. It is reported as one of the obstacles in finding an effective intervention for tinnitus. Methods: ClinicalTrials.gov (CT.gov) was used to identify all registered interventional tinnitus trials up to December 2015. A standardized search was used to find corresponding publications up to March 2018. The prespecified outcomes in CT.gov were compared with the outcomes reported in corresponding publication(s). The effects of the (lack of) statistical significance of trial results and the effects of funding source on record adherence were evaluated. Changes in registration elements were assessed with the Archive site of CT.gov. Results: We found corresponding publications for 60 (64.5%) of 93 eligible tinnitus trials registered in CT.gov. Of all the publications, five (7.5%) fully reported outcome measures entirely in line with the prespecified outcome measures. Discrepancies between the prespecified and reported outcomes were found in a total of 51 (76.1%) of the studies for primary outcomes, whereas 62 (92.5%) of the studies had discrepancies in secondary outcomes. In secondary outcomes, statistical significance of trial results influenced CT.gov record adherence. In addition, there was a statistically significant difference in the rate of discrepancy in industry-funded [n = 98 (87.5%) discrepant outcomes] and non-industry funded trials [n = 172 (74.5%) discrepant outcomes] (p = 0.01). Finally, 15 (25.9%) trialists made modifications in registered outcome measures during or after the trial period. Conclusion: Tinnitus trials suffer from substantial outcome reporting bias. Awareness of its presence must be raised to limit the obstacles of finding an effective intervention for tinnitus.

Cochlear implantation for patients with tinnitus - A systematic review.

BACKGROUND: Cochlear implantation (CI) is used in patients with severe-to-profound hearing loss when hearing aids provide limited or no benefit for speech perception. Studies on this topic reported tinnitus reduction as a common side effect of the electrical activation after cochlear implantation. So far, it is unclear what the effect is when patients do receive their implant primarily because of tinnitus complaints. OBJECTIVES: To assess the effectiveness of the electrical stimulation with a cochlear implant in patients with tinnitus as a primary complaint, by systematically reviewing the literature. METHODS: Two independent authors identified studies, extracted data and assessed risk of bias of included studies. Original studies reporting outcomes of electrical stimulation by cochlear implantation for primarily tinnitus (defined as severe or incapacitating distress levels) were included, if they reported a follow-up of at least three months. The pre- and post-implantation tinnitus distress scores on single and/or multi-item questionnaires of the included studies were extracted. RESULTS: In total, 4091 unique articles were retrieved. After screening titles, abstracts and full texts, we included seven prospective cohort studies (105 subjects in total, range: 10-26). All studies had considerable risks of bias. All tinnitus patients in the included studies had asymmetrical hearing loss or single-sided deafness. A statistically significant tinnitus distress improvement based on tinnitus questionnaire scores was found in every study. CONCLUSION: Our systematic review reveals that electrical stimulation by cochlear implants in patients with a primary complaint of tinnitus has a positive impact on tinnitus distress. Nevertheless, only small sample sizes were found and studies showed considerable risks of bias.a.

Sound therapy for cochlear implant users with tinnitus.

OBJECTIVE: Despite the positive effect of a cochlear implant (CI) on tinnitus in many patients, tinnitus remains a problem for a significant proportion of CI users. We investigated the acceptability and effect of sound therapy (a combination of natural background sounds and one concise tinnitus counselling session) on tinnitus and speech perception in CI users who still experienced tinnitus during CI use. DESIGN AND STUDY SAMPLE: Thirty-two CI users (32-78 years) participated in phase 1: a test at the clinic to evaluate six background sounds provided by the sound processor. Eighteen out of the 32 CI users participated in phase 2: an optional take-home evaluation of 2 weeks without sound therapy, followed by 5 weeks with sound therapy, ending with an evaluation visit. RESULTS: Thirty subjects (93.8%) found at least one background sound acceptable. In phase 2, a small improvement with sound therapy was found for tinnitus loudness, annoyance, and intrusiveness. 50% of the subjects subjectively reported benefit of sound therapy. Especially the sense of control on their tinnitus was highly appreciated. No detrimental effect on speech perception was observed. CONCLUSION: The background sounds were acceptable and provided tinnitus relief in some CI users with tinnitus during CI use.

Trial registration, publication rate and characteristics in the research field of otology: A cross-sectional study.

OBJECTIVES: To examine 1) the publication rate of registered otology trials in ClinicalTrials.gov, 2) the public availability of the results, 3) the study characteristics associated with publication, and 4) the time to publication after trial completion. BACKGROUND: Publication bias, the publication or non-publication of research findings, depending on the nature and direction of results, is accountable for wrong treatment decisions. The extent of publication bias in otology trials has not been evaluated. METHODS: All registered otology trials were extracted from ClinicalTrials.gov with completion date up to December 2015. A search strategy was used to identify corresponding publications up to June 2017, providing at least 18 months to publish the results after trial completion. Characteristics were obtained from ClinicalTrials.gov and corresponding publications. Regression models were used to examine study characteristics associated with publication or non-publication. RESULTS: From the 419 trials identified on ClinicalTrials.gov, 225 (53.7%) corresponding publications were found in PubMed. Among these, 109 (48.4%) publications were cited on ClinicalTrials.gov and 124 (55.1%) articles reported the National Clinical Trial registry number. For 36 (8.6%) trials, results were only reported in ClinicalTrials.gov. Trials with a biological intervention were more likely to be published than studies involving drugs (odds ratio (OR) 10.41, 95% confidence interval (CI) 1.26-86.22, P = 0.030). Trials funded by industry were less likely to be published (OR 0.46, CI 0.25-0.84, P = 0.011). The median trial duration was 20 months (interquartile range (IQR) 26 months), and median time from trial completion to publication was 24 months (IQR 22 months). CONCLUSION: In 37.7% of the registered otology trials the results remained unpublished, even several years after trial completion. With little citations on ClinicalTrials.gov and low reporting of the Clinical Trial registry number, the accessibility is limited. Our findings show that there is room for improvement in accuracy of trial registration and publication of results, in order to diminish publication bias in otology studies.

Reliability of the reflux finding score for infants in flexible versus rigid laryngoscopy.

OBJECTIVES: The Reflux Finding Score for Infants (RFS-I) was developed to assess signs of laryngopharyngeal reflux (LPR) in infants. With flexible laryngoscopy, moderate inter- and highly variable intraobserver reliability was found. We hypothesized that the use of rigid laryngoscopy would increase reliability and therefore evaluated the reliability of the RFS-I for flexible versus rigid laryngoscopy in infants. METHODS: We established a set of videos of consecutively performed flexible and rigid laryngoscopies in infants. The RFS-I was scored twice by 4 otorhinolaryngologists, 2 otorhinolaryngology fellows, and 2 inexperienced observers. Cohen's and Fleiss' kappas (k) were calculated for categorical data and the intraclass correlation coefficient (ICC) was calculated for ordinal data. RESULTS: The study set consisted of laryngoscopic videos of 30 infants (median age 7.5 (0-19.8) months). Overall interobserver reliability of the RFS-I was moderate for both flexible (ICC = 0.60, 95% CI 0.44-0.76) and rigid (ICC = 0.42, 95% CI 0.26-0.62) laryngoscopy. There were no significant differences in reliability of overall RFS-I scores and individual RFS-I items for flexible versus rigid laryngoscopy. Intraobserver reliability of the total RFS-I score ranged from fair to excellent for both flexible (ICC = 0.33-0.93) and rigid (ICC = 0.39-0.86) laryngoscopies. Comparing RFS-I results for flexible versus rigid laryngoscopy per observer, reliability ranged from no to substantial (k = -0.16-0.63, mean k = 0.22), with an observed agreement of 0.08-0.35. CONCLUSION: Reliability of the RFS-I was moderate and did not differ between flexible and rigid laryngoscopies. The RFS-I is not suitable to detect signs or to guide treatment of LPR in infants, neither with flexible nor with rigid laryngoscopy.