An audibility model of the headband trial with a bone conduction device in single-sided deaf subjects.

OBJECTIVE: Modelling the head-shadow effect compensation and speech recognition outcomes, we aimed to study the benefits of a bone conduction device (BCD) during the headband trial for single-sided deafened (SSD) subjects. DESIGN: This study is based on a database of individual patient measurements, fitting parameters, and acoustic BCD properties retrospectively measured on a skull simulator or from existing literature. The sensation levels of the Bone-Conduction and Air-Conduction sound paths were compared, modelling three spatial conditions with speech in quiet. We calculated the phoneme score using the Speech Intelligibility Index for the three conditions in quiet and seven in noise. STUDY SAMPLE: Eighty-five SSD adults fitted with BCD during headband trial. RESULTS: According to our model, most subjects did not achieve a full head-shadow effect compensation with the signal at the BCD side and in front. The modelled speech recognition in the quiet conditions did not improve with the BCD on the headband. In noise, we found a slight improvement in some specific conditions and minimal worsening in others. CONCLUSIONS: Based on an audibility model, this study challenges the fundamentals of a BCD headband trial in SSD subjects. Patients should be counselled regarding the potential outcome and alternative approaches.

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.

Systematic Review on the Trial Period for Bone Conduction Devices in Single-Sided Deafness: Rates and Reasons for Rejection.

OBJECTIVE: To systematically review the literature to evaluate the trial period of bone conduction devices (BCDs) for adult patients with single-sided deafness (SSD). DATA SOURCES: The PubMed, Embase, and Cochrane Library databases were searched from their inception up to August 15, 2016 for SSD, BCD, and their synonyms. STUDY SELECTION: In total, 523 articles were retrieved, of which 12 satisfied the eligibility quality criteria. Our outcomes of interest were: 1) the BCD implantation rejection percentage, 2) reasons to reject BCD implantation, and 3) possible prognostic factors predicting the trial outcome. DATA EXTRACTION AND SYNTHESIS: At critical appraisal, six studies (n = 471 patients) scored a moderate to high directness of evidence and a medium or low risk of bias and were selected for data extraction. Due to heterogeneity between studies, pooling of data for meta-analysis was not feasible. Therefore, results of studies were summarized per outcome: 1) after the BCD trial, 32.0 to 69.6% of SSD patients rejected BCD implantation, 2) the three main reasons for rejection were experiencing limited benefit from the device, patients fearing or being unfit for surgery and cosmetic aspects, 3) no clear prognostic factors predicting the trial outcome could be identified. CONCLUSION: Roughly half of patients rejected BCD implantation after a trial period. From the current literature it is unclear which patients could benefit most from BCD implantation. High level of evidence studies should be conducted to investigate possible prognostic factors that predict the BCD trial outcome.

Incorporating ceiling effects during analysis of speech perception data from a paediatric cochlear implant cohort.

OBJECTIVE: To compare speech perception between children with a different age at cochlear implantation. DESIGN: We evaluated speech perception by comparing consonant-vowel-consonant (auditory) (CVC(A)) scores at five-year follow-up of children implanted between 1997 and 2010. The proportion of children from each age-at-implantation group reaching the 95%CI of CVC(A) ceiling scores (>95%) was calculated to identify speech perception differences masked by ceiling effects. STUDY SAMPLE: 54 children implanted between 8 and 36 months. RESULTS: Although ceiling effects occurred, a CVC(A) score difference between age-at-implantation groups was confirmed (H (4) = 30.36; p < 0.001). Outperformance of early (<18 months) compared to later implanted children was demonstrated (p <0.001). A larger proportion of children implanted before 13 months compared to children implanted between 13 and 18 months reached ceiling scores. Logistic regression confirmed that age at implantation predicted whether a child reached a ceiling score. CONCLUSIONS: Ceiling effects can mask thorough delineation of speech perception. However, this study showed long-term speech perception outperformance of early implanted children (<18 months) either including or not accounting for ceiling effects during analysis. Development of long-term assessment tools not affected by ceiling effects is essential to maintain adequate assessment of young implanted infants.

Effectiveness of Earplugs in Preventing Recreational Noise-Induced Hearing Loss: A Randomized Clinical Trial.

IMPORTANCE: The incidence of hearing loss has risen in past years. Attendance at music festivals and concerts may contribute to this increasing problem. OBJECTIVE: To assess the effectiveness of earplugs in preventing temporary hearing loss immediately following music exposure. DESIGN, SETTING, AND PARTICIPANTS: A randomized, single-blind clinical trial was conducted on September 5, 2015, at an outdoor music festival in Amsterdam, the Netherlands. Normal-hearing adult volunteers were recruited via social media. An exclusion criterion was the participants' intention to wear earplugs. Of the 86 volunteers assessed, 51 were included in the study. All analyses were performed on an intention-to-treat basis. INTERVENTIONS: Participants were randomly assigned to a group using earplugs or an unprotected group during a 4½-hour festival visit. MAIN OUTCOMES AND MEASURES: The primary study outcome was a temporary threshold shift (TTS) on the audiogram, primarily for frequencies at 3 and 4 kHz. Secondary study outcomes included distortion product otoacoustic emission (DPOAE) measurements and claims of tinnitus using a questionnaire and tinnitus matching experiments. RESULTS: Of 51 participants included, 25 were randomized to the earplug group and 26 to the unprotected group. Nine in each group (36% and 35%, respectively) were men, and the mean (SD) ages were 27.3 (5.6) years in the earplug group and 27.0 (6.2) years in the unprotected group. Baseline demographics were similar in both groups. The time-averaged, equivalent A-weighted sound pressure level experienced was 100 dBA during the festival. A TTS over frequencies at 3 and 4 kHz after exposure was seen in 4 of 50 ears (8%) in the earplug group compared with 22 of 52 ears (42%) in the unprotected group (P < .001). The relative risk for a TTS after exposure was 5.3 (95% CI, 2.0-14.3) for the unprotected group vs the earplug group. The number needed to treat with earplugs for preventing 1 TTS was 2.9. The DPOAE amplitudes decreased significantly more over the frequencies 2 to 8 kHz in the unprotected group: the mean (SD) decrease in magnitude was 0.6 (2.8) dB in the earplug group vs 2.2 (1.9) dB in the unprotected group (P = .04). Newly induced tinnitus following sound exposure occurred in 3 of the 25 participants (12%) in the earplug group vs 10 of 25 (40%) in the unprotected group (difference, 28%; 95% CI, 3.6%-49.0%; P = .02). CONCLUSIONS AND RELEVANCE: Earplug use is effective in preventing temporary hearing loss after loud music exposure. The present randomized clinical trial adds proof to the scarce evidence and knowledge on this topic, which is a growing global problem. TRIAL REGISTRATION: trialregister.nl Identifier: NTR5401.