Geerte G. J. Ramakers

The effect of cochlear implantation on tinnitus in patients with bilateral hearing loss: A systematic review

To present an overview of the effect of cochlear implantation on tinnitus in adults with bilateral sensorineural hearing loss.

Effect of unilateral and simultaneous bilateral cochlear implantation on tinnitus: A Prospective Study.

To determine the effect of cochlear implantation on tinnitus perception in patients with severe bilateral postlingual sensorineural hearing loss and to demonstrate possible differences between unilateral and bilateral cochlear implantation.

Stable benefits of bilateral over unilateral cochlear implantation after two years: A randomized controlled trial

To investigate hearing capabilities and self‐reported benefits of simultaneous bilateral cochlear implantation (BiCI) compared with unilateral cochlear implantation (UCI) after a 2‐year follow‐up and to evaluate the learning effect of cochlear implantees over time.

Cochlear implantation in children with unilateral hearing loss: A systematic review.

To systematically review the literature on cochlear implantation (CI) for children with unilateral hearing loss (UHL).

Development of a Squelch Effect in Adult Patients After Simultaneous Bilateral Cochlear Implantation

Objectives: To investigate whether a squelch effect occurs in the first 3 years after simultaneous bilateral cochlear implantation and to investigate whether this effect increases during follow-up. Study Design: Prospective study as part of a multicenter randomized controlled trial that compares simultaneous bilateral cochlear implantation to sequential and unilateral cochlear implantation. Setting: Tertiary referral center. Patients: Nineteen postlingually deafened adults. Intervention: Simultaneous bilateral cochlear implantation. Main Outcome Measure: The squelch effect, measured yearly with a speech-intelligibility-in-noise test with spatially separated sources. Bilateral results were compared to unilateral results in which the cochlear implant at the noise side was turned off. The squelch effect was investigated for the patients’ best performing ear and for the left and right ears separately. Results: In 13 individual patients, a squelch effect was present after 1 year. This number increased during follow-up years. On group level, a squelch effect was present in patients’ best performing ear after 2 and 3 years (1.9 dB). A squelch effect was present in both ears after 3 years (AS: 1.7 dB, AD: 1.3 dB). Conclusion: Patients who underwent simultaneous bilateral cochlear implantation developed a measurable benefit from the squelch effect after 2 years in their best performing ear and after 3 years in both ears. These observations suggest that the brain learns to use interaural differences to segregate sound from noise after simultaneous bilateral cochlear implantation. The squelch effect increased over time which suggests a growth in cortical integration and differentiation of inputs from bilateral CIs due to brain plasticity. Trial Registration: Dutch Trial Register NTR1722. Level of evidence: 1b.

The Effect of Earplugs in Preventing Hearing Loss From Recreational Noise Exposure: A Systematic Review

IMPORTANCE The prevalence of hearing loss among children and adolescents is rising dramatically, caused mainly by increased exposure to recreational noise. OBJECTIVE To present a systematic overview of the effectiveness of wearing earplugs to music venues, such as nightclubs and concert halls, to prevent hearing loss and tinnitus directly after exposure. EVIDENCE ACQUISITION PubMed, EMBASE, and the Cochrane Library databases were searched for articles from database inception to June 22, 2015, using the keywords music and earplugs and all synonyms. Titles, abstracts, and full text of retrieved articles were screened for eligible articles. The directness of evidence (relevance of the assessed articles) and risk of bias of eligible articles were assessed. For the included articles, the study characteristics and data on our outcomes of interest (hearing loss and tinnitus) were extracted. Data analysis occurred from June 22 to July 3, 2015. FINDINGS Of 228 articles screened, 4 were eligible for critical appraisal. After critical appraisal, 2 studies with a high directness of evidence and low or moderate risk of bias remained for data extraction. Only 1 of these articles was a randomized clinical trial, which found significantly lower postconcert differences in thresholds and a lower proportion of threshold shifts in the group using earplugs compared with the unprotected group. In the other study, only 3 individuals wore earplugs, and no significant differences were found between the 2 groups. CONCLUSIONS AND RELEVANCE The available evidence on the effectiveness of earplugs in preventing hearing damage directly after recreational music exposure is scarce. Only 1 well-conducted randomized clinical trial was found, which showed that wearing earplugs to concerts is effective in reducing postconcert threshold shifts. There is a need for further research on this topic to strengthen the level of evidence. Physicians should promote awareness on the risks of recreational noise and recommend the use of earplugs among their patients who visit music venues.

Effect of unilateral and simultaneous bilateral cochlear implantation on tinnitus: A randomized controlled trial

To determine the effect of cochlear implantation on tinnitus perception in patients with severe bilateral postlingual sensorineural hearing loss and to demonstrate possible differences between unilateral and bilateral cochlear implantation.

Agreement between health utility instruments in cochlear implantation

The objectives of our study were threefold: to compare health utility scores measured with different health utility instruments in adult patients with bilateral deafness, to compare the change in health utility scores after unilateral or bilateral cochlear implantation using the different health utility instruments and to assess which health utility instrument would be the most appropriate for future studies on cochlear implantation.

Objective and Subjective Measures of Simultaneous vs Sequential Bilateral Cochlear Implants in Adults: A Randomized Clinical Trial

Importance To date, no randomized clinical trial on the comparison between simultaneous and sequential bilateral cochlear implants (BiCIs) has been performed. Objective To investigate the hearing capabilities and the self-reported benefits of simultaneous BiCIs compared with those of sequential BiCIs. Design, Setting, and Participants A multicenter randomized clinical trial was conducted between January 12, 2010, and September 2, 2012, at 5 tertiary referral centers among 40 participants eligible for BiCIs. Main inclusion criteria were postlingual severe to profound hearing loss, age 18 to 70 years, and a maximum duration of 10 years without hearing aid use in both ears. Data analysis was conducted from May 24 to June 12, 2016. Interventions The simultaneous BiCI group received 2 cochlear implants during 1 surgical procedure. The sequential BiCI group received 2 cochlear implants with an interval of 2 years between implants. Main Outcomes and Measures First, the results 1 year after receiving simultaneous BiCIs were compared with the results 1 year after receiving sequential BiCIs. Second, the results of 3 years of follow-up for both groups were compared separately. The primary outcome measure was speech intelligibility in noise from straight ahead. Secondary outcome measures were speech intelligibility in noise from spatially separated sources, speech intelligibility in silence, localization capabilities, and self-reported benefits assessed with various hearing and quality of life questionnaires. Results Nineteen participants were randomized to receive simultaneous BiCIs (11 women and 8 men; median age, 52 years [interquartile range, 36-63 years]), and another 19 participants were randomized to undergo sequential BiCIs (8 women and 11 men; median age, 54 years [interquartile range, 43-64 years]). Three patients did not receive a second cochlear implant and were unavailable for follow-up. Comparable results were found 1 year after simultaneous or sequential BiCIs for speech intelligibility in noise from straight ahead (difference, 0.9 dB [95% CI, –3.1 to 4.4 dB]) and all secondary outcome measures except for localization with a 30° angle between loudspeakers (difference, –10% [95% CI, –20.1% to 0.0%]). In the sequential BiCI group, all participants performed significantly better after the BiCIs on speech intelligibility in noise from spatially separated sources and on all localization tests, which was consistent with most of the participants’ self-reported hearing capabilities. Speech intelligibility-in-noise results improved in the simultaneous BiCI group up to 3 years following the BiCIs. Conclusions and Relevance This study shows comparable objective and subjective hearing results 1 year after receiving simultaneous BiCIs and sequential BiCIs with an interval of 2 years between implants. It also shows a significant benefit of sequential BiCIs over a unilateral cochlear implant. Until 3 years after receiving simultaneous BiCIs, speech intelligibility in noise significantly improved compared with previous years. Trial Registration trialregister.nl Identifier: NTR1722

Development and internal validation of a multivariable prediction model for tinnitus recovery following unilateral cochlear implantation: a cross-sectional retrospective study

Objective To develop and internally validate a prediction model for tinnitus recovery following unilateral cochlear implantation. Design A cross-sectional retrospective study. Setting A questionnaire concerning tinnitus was sent to patients with bilateral severe to profound hearing loss, who underwent unilateral cochlear implantation at the University Medical Center Utrecht, the Netherlands, between 1 January 2006 and 31 December 2015. Participants Of 137 included patients, 87 patients experienced tinnitus preoperatively. Data of these 87 patients were used to develop the prediction model. Primary and secondary outcome measures The outcome of the prediction model was tinnitus recovery. Investigated predictors were: age, gender, duration of deafness, preoperative hearing performance, tinnitus duration, severity and localisation, follow-up duration, localisation of cochlear implant (CI) compared with tinnitus side, surgical approach, insertion depth of the electrode, CI brand and difference in hearing threshold following cochlear implantation. Multivariable backward logistic regression was performed. Missing data were handled using multiple imputation. The performance of the model was assessed by the calibrative and discriminative ability of the model. The prediction model was internally validated using bootstrapping techniques. Results The tinnitus recovery rate was 40%. A lower preoperative Consonant-Vowel-Consonant (CVC) score, unilateral localisation of tinnitus and larger deterioration of residual hearing at 250 Hz revealed to be relevant predictors for tinnitus recovery. The area under the receiver operating characteristics curve (AUC) of the initial model was 0.722 (IQR: 0.703–0.729). After internal validation of this prediction model, the AUC decreased to 0.696 (IQR: 0.667–0.700). Conclusion and relevance Lower preoperative CVC score, unilateral localisation of tinnitus and larger deterioration of residual hearing at 250 Hz were significant predictors for tinnitus recovery following unilateral cochlear implantation. The performance of the model developed in this retrospective study is promising. However, before clinical use of the model, the conduction of a larger prospective study is recommended.