Cochlear Implant in Patients With Sudden Unilateral Sensorineural Hearing Loss and Associated Tinnitus

Early effects of very early cochlear implant activation on tinnitus

BACKGROUND

Cochlear implantation (CI) has long been the standard of care for patients with severe-to-profound hearing impairment. Yet the benefits of CI extend far beyond speech understanding, with mounting recent literature supporting its role in tinnitus abatement. However, those studies have uniformly analyzed the effects of tinnitus after the traditional 3-4 weeks waiting period between CI surgery and device activation. As many clinics are shifting these waiting intervals to become shorter (in some cases within 24 hours, little is known about tinnitus abatement very early in the postoperative period. The aim of this study was to compare preoperative and postoperative tinnitus handicaps in this unique but growing population of very early-activated patients.

METHODS

Twenty-seven adults with severe-to-profound hearing impairment with chronic tinnitus (>6 months) were included. Patients with concomitant psychiatric disorders were excluded. All patients were implanted with the same array and were switched on within 24 hours after the surgery. Tinnitus Handicap Inventory (THI) was recorded preoperatively, immediately after activation at 24 hours postoperatively, at 1 week, 2 weeks, and I month after activation. Wilcoxon signed-rank test was used to compare values between preoperative assessment and respective fitting sessions.

RESULTS

Mean THI 24 hours after implantation increased in comparison to that assessed preoperatively (77.6 vs 72.5, p = 0.001). By 1 week after surgery, the THI had decreased to 54.9 ( p < 0.001). This trend continued and was statistically significant at 2 weeks (36.0, p < 0.001) and 1 month (28.5, p < 0.001).

CONCLUSION

On average, most patients with tinnitus will note a significant improvement in their tinnitus handicap when activated within 24 hours of CI. However, tinnitus does increase between surgery and 24 hours, most likely reflecting not only intracochlear changes, but modulation of the entire auditory pathway. Following this early rise, the tinnitus continues to abate over the following month. Patients with tinnitus may benefit from early activation, although should be counseled that they may experience an exacerbation during the very early postoperative period.

Influence of tinnitus annoyance on hearing-related quality of life in cochlear implant recipients

Tinnitus is a common symptom in cochlear implant (CI) recipients. There is no clear evidence of the influence of tinnitus on hearing-related quality of life (QoL) in this population. The aim of this study was to assess the relationship between hearing-related QoL measured by the Speech, Spatial and Qualities of Hearing scale (SSQ12) and tinnitus annoyance or perceived change in tinnitus annoyance after cochlear implantation. The study sample consisted of 2322 implanted adults across France, Germany, Ireland, Italy, the Netherlands, Sweden and the United Kingdom. Information relating to QoL measured using the SSQ12 and tinnitus annoyance and change in tinnitus annoyance, assessed using single-item questions, were collected one or more years post-implantation. The relationship between SSQ12 score and tinnitus annoyance or change in tinnitus annoyance was analysed using linear models adjusted for age and unilateral versus bilateral implants. Tukey pairwise tests were used to compare mean SSQ12 scores across levels of tinnitus annoyance and changes. Tinnitus prevalence was 33.9% post-implantation. Recipients with tinnitus had a significantly lower SSQ12 score than recipients without tinnitus. SSQ scores varied significantly with tinnitus annoyance, age and unilateral versus bilateral implants. Overall, CI recipients who experienced less bothersome tinnitus reported better hearing-related QoL. Healthcare professionals should be aware of the influence of tinnitus on CI recipients’ hearing to manage patient expectations.

Genotype-Phenotype Correlation for Predicting Cochlear Implant Outcome: Current Challenges and Opportunities

The use and utility of cochlear implantation has rapidly increased in recent years as technological advances in the field have expanded both the efficacy and eligible patient population for implantation. This review aims to serve as a general overview of the most common hearing disorders that have favorable auditory outcomes with cochlear implants (CI). Hearing loss in children caused by congenital cytomegalovirus infection, syndromic conditions including Pendred Syndrome, and non-syndromic genetic conditions such as hearing impairment associated with GJB2 mutations have shown to be successfully managed by CI. Furthermore, cochlear implantation provides the auditory rehabilitation for the most common etiology of hearing loss in adults and age-related hearing loss (ARHL) or presbycusis. However, in some cases, cochlear implantation have been associated with some challenges. Regarding implantation in children, studies have shown that sometimes parents seem to have unrealistic expectations regarding the ability of CI to provide auditory rehabilitation and speech improvement. Given the evidence revealing the beneficial effects of early intervention via CI in individuals with hearing disorders especially hearing loss due to genetic etiology, early auditory and genetic screening efforts may yield better clinical outcomes. There is a need to better understand genotype-phenotype correlations and CI outcome, so that effective genetic counseling and successful treatment strategies can be developed at the appropriate time for hearing impaired individuals.

Estimating Real-World Performance of Percutaneously Coupled Bone-Conduction Device Users With Severe-to-Profound Unilateral Hearing Loss

Purpose The bone-conduction device attached to a percutaneous screw (BCD) is an important treatment option for individuals with severe-to-profound unilateral hearing loss (UHL). Clinicians may use subjective questionnaires and speech-in-noise measures to evaluate BCD use in this patient population; however, the translation of these metrics to real-world aided performance is unclear. The purpose of this study was twofold: first, to measure speech-in-noise performance in BCD users with severe-to-profound UHL in a simulated real-world environment, relative to individuals with normal hearing bilaterally; second, to determine if BCD users' subjective reports of aided performance relate to simulated real-world performance. Method A between-subjects design with two groups was conducted with 14 adults with severe-to-profound UHL (BCD group) and 10 age-matched participants with normal hearing bilaterally (control group). Speech-in-noise tests were administered in an eight-speaker R-Space simulating a real-world environment. To further explore speech-in-noise evaluation methods for this population, testing was also completed in a clinically common two-speaker array. The effects of various microphone settings on performance were explored for BCD users. Subjective performance was measured with the Abbreviated Profile of Hearing Aid Benefit (APHAB; Cox & Alexander, 1995) and the Speech, Spatial and Qualities of Hearing Scale (Gatehouse & Noble, 2004). Statistical analyses to explore relationships between variables included repeated-measures analysis of variance, regression analyses, independent-samples t tests, nonparametric Mann-Whitney tests, and correlations. Results In the simulated real-world environment, BCD group participants struggled with speech-in-noise understanding compared to control group participants. BCD benefit was observed for all microphone settings when speech stimuli were presented to the side with the BCD. When adaptive directional or fixed directional microphone settings were used, a relationship was noted between simulated real-world speech-in-noise performance for speech stimuli presented to the side with the BCD and subjective reports on the Background Noise subscale of the APHAB. Conclusions The Background Noise subscale of the APHAB may help estimate real-world speech-in-noise performance for BCD users with severe-to-profound UHL for signals of interest presented to the implanted side, specifically when adaptive or fixed directional microphone settings are used. This subscale may provide an efficient and accessible alternative to assessing real-world speech-in-noise performance in lieu of less clinically available measurement tools, such as an R-Space.

Restoration of cortical symmetry and binaural function: Cortical auditory evoked responses in adult cochlear implant users with single sided deafness

Background

Cochlear implantation for single-sided deafness (SSD) is the only treatment option with the potential to restore binaural hearing cues. Significant binaural benefit has been measured in adults by speech in noise and localisation tests, who receive a cochlear implant for SSD, however, little is known on the cortical changes that help provide this benefit. In the present study, detection of sound in the auditory cortex, speech testing and localisation was used to investigate the ability of a cochlear implant (CI) to restore auditory cortical latencies and improve binaural benefit in the adult SSD population.

Methods

Twenty-nine adults with acquired single-sided deafness who received a CI in adulthood were studied. Speech perception in noise was tested using the Bamford-Kowal-Bench speech-in-noise test, localisation ability was measured using the auditory speech sounds evaluation (AδE) localisation test and cortical auditory evoked responses, comparing N1-P2 latencies recorded from the normal hearing ear and cochlear implant were used to investigate the synchrony of the cortical pathway from the CI and normal hearing ear (NHe) with binaural hearing function.

Results

There was a significant improvement in speech perception in noise in all spatial configurations S0/N0 (Z = -3.066, p<0.002), S0/NHE (Z = -4.031, p<0.001), SCI/NHE (Z = -3.851, p<0.001). Localization significantly improved when tested with the cochlear implant on (p<0.001) with a shorter duration of deafness correlating to a greater improvement in localisation ability F(1:18) = 6.854; p = 0.017). There was no significant difference in N1-P2 latency recorded from the normal hearing ear and the CI.

Conclusion

Cortical auditory evoked response latencies recorded from the CI and NHe showed no significant difference, indicating that the detection of sound in the auditory cortex occurred simultaneously, providing the cortex with auditory information for binaural hearing.