Tinnitus suppression following cochlear implantation. A multifactorial investigation

Changes in Tinnitus Characteristics and Residual Inhibition following Cochlear Implantation: A Prospective Analysis

This study aims to explore the effect of cochlear implantation on tinnitus perception. A prospective study was conducted on 72 adult hearing-impaired patients to evaluate tinnitus perception before and after cochlear implantation, using standardized tinnitus questionnaires (the tinnitus sample case-history questionnaire, tinnitus functional index (TFI), and tinnitus handicap inventory (THI)). A large variety of demographic and hearing- and implant-related data was collected from patient hospital records to explore possible associations with the implantation effect. The prevalence of tinnitus complaints before implantation was 58.3%. The temporary induction or aggravation of tinnitus immediately after surgery was noted in 20% and 46.7% of patients, respectively. When evaluated 3 months after implantation, 60% of tinnitus patients experienced a clinically significant reduction in their complaints; most of the improvements were experienced immediately after activation of the implant. Only the scores for TFI and THI at baseline were found to be significantly correlated with a reduction in TFI scores after implantation. In 80% of tinnitus patients, the tinnitus remained suppressed for some time after taking off the device. The large subset of patients with residual inhibition supports the involvement of central pathophysiological processes in implantation effects on tinnitus, which are explored in this paper.

Effects of auditory rehabilitation with cochlear implant on tinnitus prevalence and distress, health-related quality of life, subjective hearing and psychological comorbidities: Comparative analysis of patients with asymmetric hearing loss (AHL), double-sided (bilateral) deafness (DSD), and single-sided (unilateral) deafness (SSD)

Introduction

Auditory rehabilitation with a cochlear implant (CI), in many cases, positively impacts tinnitus. However, it is unclear if the tinnitus-related benefit of CI is equal for patients with various indications for CI. Therefore, this study aimed to determine differences in tinnitus prevalence and distress, health-related quality of life, subjective hearing, perceived stress, and psychological comorbidities between patients diagnosed with asymmetric hearing loss (AHL), single-sided (unilateral) deafness (SSD), and double-sided (bilateral) deafness (DSD) before and six months after cochlear implantation.

Methods

One hundred-one CI candidates were included in this prospective study (39 AHL patients, 23 DSD patients, and 39 SSD patients). The patients completed questionnaires measuring tinnitus distress, health-related quality of life, subjective hearing, perceived stress, and psychological comorbidities before and 6 months after CI.

Results

The prevalence of tinnitus in the entire cohort (80.2% before CI) decreased 6 months after CI to 71.3%. The DSD group had the lowest tinnitus prevalence at both time points. The degree of tinnitus-induced distress decreased significantly in all three groups after CI. Differences in quality of life, subjective hearing, and psychological comorbidities between the groups at the study onset disappeared after CI. Significant correlations existed between anxiety, depression, and tinnitus distress in AHL and SSD but not in DSD patients before and after CI.

Discussion

Our results demonstrate significant differences between the three groups of CI candidates, which might affect the implantation outcome. These differences suggest a need for personalized psychological counseling during the auditory rehabilitation process, focusing on anxiety and depressive symptoms for SSD and AHL patients.

Experience of tinnitus in adults who have severe-to-profound hearing loss: A scoping review

Background

Tinnitus is defined as the subjective perception of sound in the absence of an external stimulus, and tinnitus disorder becomes relevant when it is associated with emotional distress, cognitive dysfunction, and/or autonomic arousal. Hearing loss is recognized as the main risk factor for the pathogenesis of tinnitus. However, clinical guidelines for tinnitus disorder provide little direction for those who have severe-to-profound hearing loss including those who are pre-lingually Deaf. The aim of this scoping review was to catalogue what is known from the existing literature regarding the experience and management of tinnitus in adults who have a severe-to-profound hearing loss.

Summary

A scoping review was conducted following the Preferred Reporting Item for Systematic Reviews and Meta-analysis extension for Scoping Reviews. Records were included if they reported an evaluation of tinnitus in adults who had severe-to-profound hearing loss. The online databases Ovid (MEDLINE, EMBASE and PsycINFO), CINAHL, ProQuest, Scopus, and Google Scholar were searched using the search terms ‘tinnitus’ (as a MESH term) and ‘deaf’ OR ‘profound hearing loss. Thirty-five records met the inclusion criteria for this review and were cataloged according to three major themes: Impact of tinnitus in deaf adults; Primary treatment of tinnitus in deaf adults; and Cochlear implant studies where tinnitus was a secondary outcome. Tinnitus symptom severity was assessed before and after intervention using tinnitus validated questionnaires in 29 records, with six further records using other assessment tools to measure tinnitus severity. Participants using cochlear implants were included in 30 studies. Medication, repetitive transcranial magnetic stimulation (rTMS), electrical promontory stimulation, and behavioral self-control therapy were each reported in single records.

Key messages

This scoping review cataloged the experience, assessment, and treatment of tinnitus in adults who have severe-to-profound hearing loss. It is shown that there is very limited research reported in this field. Although this review included many records, most focused on the provision of cochlear implants for severe-to-profound hearing loss, with assessment and measurement of tinnitus as a baseline or secondary outcome. Largely missing in the literature are empirical studies that seek firstly to understand the nature of the experience of tinnitus by people with no or little residual access to external sound.

Use of a Smartphone App for Cochlear Implant Patients With Tinnitus

Purpose Smartphone apps for tinnitus relief are now emerging; however, research supporting their use and effectiveness is lacking. Research has shown that Tinnitus Therapy sounds intended for individuals with acoustic hearing provide relief to some patients using cochlear implants (CIs) with tinnitus. Here, we evaluated the use and acceptability of a smartphone app to help CI patients with tinnitus. Method Participants completed a laboratory trial (n = 19) and an at-home trial (n = 14) using the ReSound Tinnitus Relief app to evaluate its acceptability and effectiveness in reducing their tinnitus. During the laboratory trial, participants selected a sound that was most acceptable in managing their tinnitus (termed chosen sound). Word recognition scores in quiet were obtained before and after sound therapy. Participants were randomly assigned to one of two groups for the at-home trial, that is, AB or BA, using (A) the chosen sound for 2 weeks and (B) the study sound (i.e., broadband noise at hearing threshold) for another 2 weeks. Ratings were collected weekly to determine acceptability and effectiveness of the app in reducing tinnitus loudness and annoyance. Results Results indicated that some, but not all, participants found their chosen sound to be acceptable and/or effective in reducing their tinnitus. A majority of the participants rated the chosen sound or the study sound to be acceptable in reducing their tinnitus. Word recognition scores for most participants were not adversely affected using the chosen sound; however, a significant decrease was observed for three participants. All 14 participants had a positive experience with the app during the at-home trial on tests of sound therapy acceptability, effectiveness, and word recognition. Conclusions Sound therapy using a smartphone app can be effective for many tinnitus patients using CIs. Audiologists should recommend a sound and a level for tinnitus masking that do not interfere with speech perception.

Systematic review of sound stimulation to elicit tinnitus residual inhibition

BACKGROUND

Residual Inhibition is considered as tinnitus alteration immediately after exposure to sound. Its clinical significance and correlation with the pathophysiology and treatment prognosis of tinnitus remain enigmatic. The objective of this review is to critically appraise scientific evidence regarding the residual inhibition prevalence and how it is correlated with different sound stimuli.

METHODS

A systematic review of tinnitus Residual Inhibition (RI) studies was performed, focusing on prevalence, methods used, stimuli presented and responses obtained. A literature search (PubMed, Cochrane Central Register of Controlled Trials, Scopus, MEDLINE) was conducted. Seventeen studies involving 1066 patients fulfilled the inclusion criteria. Sound stimulation was performed using pure tones, customized sounds, narrow- and broadband noises, and modulated sounds.

RESULTS

Sound stimuli exposure produced complete RI of tinnitus in 34.5% of patients (range 5.6-72%), with higher RI rates after stimulation with pure tones and narrowband noise centered to the tinnitus perceived pitch. RI duration tends to increase when stimuli duration increases.

CONCLUSIONS

RI is frequent and can be induced by narrow-band noise (NBN), broadband noise (BBN), pure tones, customized sounds and modulated sounds. Adequate evidence to support the use of RI as a tool for tinnitus phenotyping or as a management option is pending. Further clinical research exploring the profile of patients with RI and its potential use as prognostic factor should be conducted.

A Cross-Sectional Questionnaire Study of Tinnitus Awareness and Impact in a Population of Adult Cochlear Implant Users

Supplemental Digital Content is available in the text.

Objectives:

The primary aim was to identify the proportion of individuals within the adult cochlear implant population who are aware of tinnitus and those who report a negative impact from this perception, using a bespoke questionnaire designed to limit bias. A secondary aim was to use qualitative analysis of open-text responses to identify themes linked to tinnitus perception in this population.

Design:

A cross-sectional questionnaire study of a large clinical population who received an implant from Cambridge University Hospitals, United Kingdom.

Results:

Seventy-five percent of respondents reported tinnitus awareness. When impact scores for six areas of difficulty were ranked, 13% of individuals ranked tinnitus their primary concern and nearly a third ranked tinnitus in the top two positions. Tinnitus impact was not found to reduce with duration since implantation. The most common open-text responses were linked to a general improvement postimplantation and acute tinnitus alleviation specific to times when the device was in use.

Conclusions:

Tinnitus is a problem for a significant proportion of individuals with a cochlear implant. Clinicians, scientists, and cochlear implant manufacturers should be aware that management of tinnitus may be a greater priority for an implantee than difficulties linked to speech perception. Where a positive effect of implantation was reported, there was greater evidence for masking of tinnitus via the implant rather than reversal of maladaptive plasticity.

Models to predict positive and negative effects of cochlear implantation on tinnitus

Objectives

The effect of cochlear implantation on tinnitus is heterogeneous: implantation does not always reduce tinnitus and may even worsen tinnitus. Therefore, it is important to know which factors influence the consequences of cochlear implantation for tinnitus. To date, no consensus has been reached regarding the factors that influence tinnitus. This study aimed to create prognostic models, using binary logistic regression analyses to predict positive or negative changes in tinnitus after cochlear implantation.

Methods

For this study we retrospectively sent two questionnaire packages to 117 cochlear implant patients.

Results

In the binary logistic regression analyses of the responses to the questionnaires, it was not possible to create a significant model to predict a positive effect of cochlear implantation on tinnitus. However, a negative effect of cochlear implantation on tinnitus was predictable, using a backward stepwise selection method in a model including the Abbreviated Profile of Hearing Aid Benefit (APHAB) and Tinnitus Handicap Questionnaire (THQ) (P < .001, Nagelkerke R² = 0.529).

Conclusions

Our results suggest that the lower the preoperative tinnitus handicap and the preoperative hearing handicap, the higher the chance that cochlear implantation will worsen tinnitus. More research needs to be done, preferable in a big prospective study, to make this model instrumental for clinical decision making and preoperative patient counselling. However, our results might suggest that preoperative THQ and APHAB screening could be meaningful. Especially in patients who are afraid to develop tinnitus or tinnitus worsening as complication of cochlear implantation.

Level of Evidence

4

Tinnitus Suppression in Cochlear Implant Patients Using a Sound Therapy App

PURPOSE

The use of acoustic stimuli to reduce the prominence of tinnitus has been used for decades. Counseling and tinnitus sound therapy options are not currently widespread for cochlear implant (CI) users. The goal of this study was to determine whether tinnitus therapy sounds created for individuals with acoustic hearing may also benefit CI users.

METHOD

Sixteen sounds from the ReSound Relief app (Version 3.0) were selected for the study. Sixteen participants were asked to rate the overall acceptability of each sound and to write the description of the sound they perceived. Sounds were streamed from an Apple™ iPod (6th generation) to the CI using a Cochlear™ Wireless Mini Microphone 2+. Thirteen participants then completed a 5-min trial where they rated their pretrial and posttrial tinnitus and the acceptability of a subset of preferred sounds. Ten out of these 13 participants completed a 2-week home trial with a preferred sound after which they answered an online tinnitus questionnaire and rated the effectiveness of the sound therapy.

RESULTS

Individual differences were large. Results from the 5-min trial showed that sounds perceived as rain, music, and waves were rated the most acceptable. For all of the participants, the posttrial tinnitus loudness rating was lower than the pretrial rating, with some participants experiencing greater difference in their tinnitus loudness than others. At the end of the 2-week home trial, 3 of 10 participants rated the effectiveness of sound therapy 70% or higher.

CONCLUSION

The results suggest that the use of tinnitus therapy sounds delivered through a CI can be acceptable and provides relief for some tinnitus sufferers.

A Quantitative Electroencephalography Study on Cochlear Implant-Induced Cortical Changes in Single-Sided Deafness with Tinnitus

The mechanism of tinnitus suppression after cochlear implantation (CI) in single-sided deafness (SSD) is not fully understood. In this regard, by comparing pre- and post-CI quantitative electroencephalography (qEEG), we explored cortical changes relevant to tinnitus improvement. In SSD patients who underwent CI, qEEG data were collected: (1) before CI, (2) 6 months post-operatively with CI-on, and (3) 30 min after CI-off and source-localized cortical activity/functional connectivity analyses were performed. Compared to the pre-operative baseline, the CI-on condition demonstrated significantly decreased activity in the right auditory- and orbitofrontal cortices (OFC) for the delta frequency band as well as decreased connectivity between the auditory cortex/posterior cingulate cortex for the delta/beta2 bands. Meanwhile, compared to the CI-off condition, the CI-on condition displayed decreased activity in the right auditory cortices/OFC for the delta band, and in bilateral auditory cortices, left inferior frontal cortex/OFC for the gamma band. However, qEEG analyses showed no significant differences between the CI-off and baseline conditions. CI induced overall decreased cortical activity and functional connectivity. However, judging from no differences between the CI-off and baseline conditions, CI-induced cortical activity and functional connectivity changes are not by cortical plastic changes, but by dynamic peripheral reafferentation.

Suppression of Tinnitus in Chinese Patients Receiving Regular Cochlear Implant Programming

Objective:

To assess the clinical effect of cochlear implant programming on tinnitus.

Methods:

Tinnitus patients (n = 234) were divided into 3 groups: (1) preoperative tinnitus (n = 108), (2) postoperative tinnitus occurring before implant switch-on at week 4 (n = 88), and (3) tinnitus occurring more than 1 year postoperatively (n = 44). Patients in each group were randomly allocated into a programming subgroup that received programming for 12 weeks postoperatively or after tinnitus occurrence or a control subgroup. Impedance testing and the Tinnitus Handicap Inventory (THI) were performed preoperatively and at 4, 6, 8, and 12 weeks postoperatively (groups 1 and 2) or after tinnitus occurrence (group 3). Comparisons were performed using t tests and chi-square tests.

Results:

Impedance was significantly lower in the programming subgroup than in the control subgroup in groups 1 and 2 at 8 and 12 weeks and in group 3 at 12 weeks. The THI scores decreased in both programming and control subgroups in all groups. However, this decrease was pronounced in the programming subgroup, whereas in the control subgroup, it occurred slowly over time.

Conclusion:

Cochlear implant programming decreases impedance and improves tinnitus symptoms.

A Series of Case Studies of Tinnitus Suppression With Mixed Background Stimuli in a Cochlear Implant

PURPOSE

Background sounds provided by a wearable sound playback device were mixed with the acoustical input picked up by a cochlear implant speech processor in an attempt to suppress tinnitus.

METHOD

First, patients were allowed to listen to several sounds and to select up to 4 sounds that they thought might be effective. These stimuli were programmed to loop continuously in the wearable playback device. Second, subjects were instructed to use 1 background sound each day on the wearable device, and they sequenced the selected background sounds during a 28-day trial. Patients were instructed to go to a website at the end of each day and rate the loudness and annoyance of the tinnitus as well as the acceptability of the background sound. Patients completed the Tinnitus Primary Function Questionnaire (Tyler, Stocking, Secor, & Slattery, 2014) at the beginning of the trial.

RESULTS

Results indicated that background sounds were very effective at suppressing tinnitus. There was considerable variability in sounds preferred by the subjects.

CONCLUSION

The study shows that a background sound mixed with the microphone input can be effective for suppressing tinnitus during daily use of the sound processor in selected cochlear implant users.

Tinnitus suppression by electric stimulation of the auditory nerve

Electric stimulation of the auditory nerve via a cochlear implant (CI) has been observed to suppress tinnitus, but parameters of an effective electric stimulus remain unexplored. Here we used CI research processors to systematically vary pulse rate, electrode place, and current amplitude of electric stimuli, and measure their effects on tinnitus loudness and stimulus loudness as a function of stimulus duration. Thirteen tinnitus subjects who used CIs were tested, with nine (70%) being "Responders" who achieved greater than 30% tinnitus loudness reduction in response to at least one stimulation condition and the remaining four (30%) being "Non-Responders" who had less than 30% tinnitus loudness reduction in response to any stimulus condition tested. Despite large individual variability, several interesting observations were made between stimulation parameters, tinnitus characteristics, and tinnitus suppression. If a subject's tinnitus was suppressed by one stimulus, then it was more likely to be suppressed by another stimulus. If the tinnitus contained a "pulsating" component, then it would be more likely suppressed by a given combination of stimulus parameters than tinnitus without these components. There was also a disassociation between the subjects' clinical speech processor and our research processor in terms of their effectiveness in tinnitus suppression. Finally, an interesting dichotomy was observed between loudness adaptation to electric stimuli and their effects on tinnitus loudness, with the Responders exhibiting higher degrees of loudness adaptation than the Non-Responders. Although the mechanisms underlying these observations remain to be resolved, their clinical implications are clear. When using a CI to manage tinnitus, the clinical processor that is optimized for speech perception needs to be customized for optimal tinnitus suppression.

Changes in the tinnitus handicap questionnaire after cochlear implantation

PURPOSE

To determine (a) changes in the Tinnitus Handicap Questionnaire (THQ) for patients using cochlear implants, (b) differences between patients who receive total or partial relief, and (c) identifiable characteristics of those who report tinnitus after implantation.

METHOD

Pre- and postoperatively, 244 adults were administered the THQ when they reported tinnitus.

RESULTS

Of the 153 patients who had tinnitus preoperatively, 94 (61%) patients reported total suppression and 59 (39%) reported a partial reduction. In 91 patients who did not have tinnitus before implantation, 11 (12%) reported tinnitus postimplantation. The THQ score decreased from 41% preimplant to 30% postimplant. The largest reductions involved social handicap and hearing. Patients with a more severe hearing loss might be more likely to experience an exacerbation of their tinnitus. We were not able to clearly identify differences between patients who received total or partial relief and the characteristics of patients who reported tinnitus after implantation. Those who acquired tinnitus had the shortest duration hearing loss (5.6 years) and were the oldest (63 years). The average THQ score of patients getting tinnitus was 29%.

CONCLUSIONS

Most tinnitus patients benefit from receiving a cochlear implant.

Tinnitus and cochlear implantation

Tinnitus is a common experience, but there is very marked heterogeneity of aetiology, perception and the extent of distress among individuals who experience tinnitus. In view of this, a modern approach to tinnitus should consider homogeneous groups of individuals. This review considers tinnitus experiences in patients undergoing cochlear implantation, this being of interest because the prevalence of tinnitus in this patient group prior to surgery may shed some light on the link between cochlear dysfunction and tinnitus Second, any change in tinnitus experience as a result of electrode placement surgery or cochlear implant activation has relevance for patient counselling and informed consent. Finally, in recent tinnitus retraining therapy literature there has been the suggestion that unilateral sound therapy for tinnitus patients may set up an unhelpful asymmetry of input to the auditory system, with possible exacerbation of contralateral tinnitus. Unilateral cochlear implant use represents the most dramatic asymmetry possible and hence is a test of that hypothesis. Relevant papers (n = 32) were identified from literature databases. The standard of reporting tinnitus results was inconsistent. Tinnitus is experienced by up to 86% of adult cochlear implant candidates, but is not universal and is only troublesome in a small proportion (reported as 27% in one study). Electrode insertion may induce tinnitus in a small (up to 4%) number of patients, but this is rare. Cochlear implant device use is associated with reduction of tinnitus intensity and awareness in up to 86% of patients, and rarely with exacerbation (up to 9%). There are some indications in the literature that the more complex the simulation strategy, the larger that effect. Specifically, unilateral cochlear implant use was generally associated with reduction of contralateral tinnitus (in up to 67% of individuals) rather than exacerbation, and so the assertion that unilateral sound therapy for tinnitus is contraindicated is not proven.

Electrical Stimulation of the Cochlea to Reduce Tinnitus

This article reviews possible neural correlates of tinnitus, including an increase in rate, a decrease in rate, periodic activity, synchronous activity across neurons, and an edge between active and inactive neurons. We make some suggestions regarding how electrical current might alter these patterns of neural activity. For example, if tinnitus were represented with periodic neural activity, then electrical stimulation would need to disrupt this periodicity. Some cases of cochlear electrical stimulation are reviewed that show the tinnitus can be reduced or eliminated with cochlear electrical stimulation although it varies across individuals. Finally, after summarizing some key observations, we suggest some next steps to bring this into a clinical application.

The effect of unilateral multichannel cochlear implant on bilaterally perceived tinnitus

CONCLUSIONS

Available multichannel cochlear implants (CIs) provide effective tinnitus suppression. More sophisticated speech strategies are more effective than analogue or slow strategies. The mechanisms by which tinnitus is suppressed by CIs are unclear; however, both acoustic masking and reorganization of the right auditory association cortex induced by the CI are possible mechanisms. CI significantly reduced the tinnitus-related Handicap as assessed by the Tinnitus handicap Inventory (THI).

OBJECTIVE

The objective of the study was to evaluate the effects of a unilateral CI on bilaterally perceived tinnitus.

PATIENTS AND METHODS

Forty-one profoundly deaf patients implanted with a multichannel CI reporting bilateral tinnitus were evaluated. All patients were asked to complete a questionnaire that evaluated the presence, location and intensity of tinnitus before and after cochlear implantation.

RESULTS

Seven patients (17%) reported the perception of a 'new tinnitus' after surgery. With the CI off tinnitus was abolished in 23 patients (56.1%) in the implanted ear and in 22 patients (53.6%) in the contralateral ear. With the CI on tinnitus was abolished in the ipsilateral ear in 27 patients (65.8%) and in the contralateral ear in 27 patients (65.8%). Statistical analysis showed a significant reduction of the total THI score and of each subscale score (p < 0.001).

Tinnitus, cochlear implants and how they affect patients

The relationship between tinnitus and cochlear implantation is an important issue that needs to be established because it may affect implant use. In this study 99 patients over 15 years of age completed pre-and post-cochlear implantation questionnaires, and underwent performance testing. The findings show that after implantation, there was marked suppression of tinnitus in both implanted and contralateral ears whilst the implant was off, and this was further enhanced when the implant was switched on. These effects are probably a combination of local and central factors. Presence of tinnitus, before or after implantation, had no detrimental effects on performance.

In conclusion, providing all other factors permit, this study recommends implanting the ear with the worst tinnitus.

Tinnitus modifications after cochlear implantation

Tinnitus can be defined as a phantom sensation in the absence of an external sound. In our study, we evaluated the effect of cochlear implant on tinnitus evolution. Among adult, postlingually deaf patients who underwent cochlear implantation at our clinic, we selected 20 subjects with pre-implantation tinnitus (group A) and 10 subjects without pre-implantation tinnitus (group B). Pre- and post-surgery tinnitus was assessed through two questionnaires: the first one dealing with tinnitus characteristics and psychosocial impact, and the second one represented by THI, an internationally validated score of evaluation of the effects of tinnitus on patient's emotions and activities of daily living. None of the patients belonging to group B developed tinnitus after surgery. As for group A, 40% of patients declared suppression of tinnitus, 30% attenuation of tinnitus after surgery, 25% reported tinnitus was unchanged and 5% reported worsening of tinnitus. In the nine patients with bilateral tinnitus (45%), after implantation tinnitus disappeared from both sides in four patients and attenuated bilaterally in four patients. A comparison between pre- and post-implantation THI scores showed decreased score in 65% of cases, unchanged score in 30% and increased score in 5%. The beneficial effect of cochlear implant on tinnitus, reported by a majority of patients, could be due to acoustic masking, to direct electrical stimulation of the acoustic nerve, and above all to a possible cochlear implantation dependent reorganization of the central auditory pathways and associative cerebral areas. In the light of these results, the authors propose (1) to include tinnitus in the selection criteria of which ear to implant; (2) to consider implantation eligibility for patients with bilateral severe hearing loss associated with severe tinnitus; and (3) to inform patients about the small risk of post-operative tinnitus worsening.

[Subjetive benefits and limitations in relation with the cochlear implant reported by adolescent and adult patients]

OBJECTIVE

To identify the subjetive benefits and limitations of the pre and postlingually adolescent and adult patients of the cochlear implants program at Clinical Hospital San Cecilio (Granada).

MATERIAL AND METHODS

Cross-sectional study of 60 pre and postlingually deaf patients who received cochlear implant with more than 12 years and at least a year of experience. A open-ended questionnaire was used to value their subjetive experience. A descriptive analysis was made and we applied the square Chi and Mann-Withney tests.

RESULTS

The average implant usage per day was greater in the postlingually patients (14.6 hours) that in the prelingually (10.4 hours). Between the acoustic benefits, both more frequent were the perception of environmental sounds and the possibility of to converse easier, specially with one or two persons. The benefit more indicated by the patients was the improvement in its mood. The perception in noise situations was the difficulty more indicated by all patients. The problems, in relation with the device, more frequently indicated were the size and the weight.

CONCLUSION

the cochlear implant provides subjetive benefits to the patients that complement their improvement in perception of the oral language and facilitate the re/integration of the deaf patients at his work and in his social life. Therefore, the speech perception tests must be complemented with another type of materials to value the result of the cochlear implant and then we will can to speak of success or failure.

Neural mechanism of residual inhibition of tinnitus in cochlear implant users

Residual inhibition is a transient suppression of tinnitus after auditory stimulation has stopped. We used positron emission tomography to study brain regions underlying residual inhibition in three tinnitus patients with cochlear implants and six normal hearing controls. Regional cerebral blood flow was measured and compared under two conditions: with tinnitus and during the residual inhibition of tinnitus. The right anterior middle and superior temporal gyri (Brodmann areas 21 and 38) were activated during residual inhibition, while the right cerebellum was activated during tinnitus perception in the tinnitus patients. No significant activation was observed in the normal controls. Our results suggest that tinnitus and residual inhibition are related to cortical networks of auditory higher-order processing, memory and attention.

[Cochlear implant in postlingual adults with progressive hearing loss]

OBJECTIVES

To analize the results of patients with cohlear implants in postlingual adults with progressive hearing loss and to analize various predictive factors.

MATERIAL AND METHODS

Prospective study of 42 patients with profound and progressive hearing loss. We analized the outcomes in the first two years of follow-up. We examined the results in regards to the of age at time of implantation, other handicaps, cause of hearing loss, age of onset, cochlear ossification and actives electrodes. We use the logo-auditory protocol developed at the University Spanish of navarra.

RESULTS

All tests presented a significative improvement in the first six months (p<0.01 Student t or Wilcoxon test). After six months the results were not statistically significant. The more important predictive factors were percentage of life with hearing loss, percentage of life with profound hearing loss, cochlear ossification and actives electrodes thus the significancy was more relevant at a follow-up period of 3 months (p<0.05 Student t or Mann-Withney test).

CONCLUSIONS

These patients showed clear benefits in a short period of time and the patients with unfavourable circumstances had a more slow progression but a similar final outcome.

Cochlear implantation for tinnitus suppression

A high prevalence of tinnitus in cochlear implant users has been demonstrated, but fortunately a large percentage of patients do report some degree of tinnitus suppression postoperatively. Improvements in the duration and intensity and the annoyance level and loudness of the perceived tinnitus postimplant have been demonstrated. The risk of worsening of the tinnitus percept after cochlear implantation is small.

Tinnitus in cochlear implant patients--a comparison with other hearing-impaired patients

As part of a quality of life study, 84 patients who received multichannel intra-cochlear cochlear implants (CIs) were evaluated regarding tinnitus problems by a questionnaire. As controls, 60 hearing aid (HA) users and 35 non-operated CI candidates were used. The prevalence of tinnitus in the CI group was 70%, and that of troublesome tinnitus was 35%. In the two other groups, the prevalences of tinnitus were 40% (HA) and 74% (non-CI). Twenty-three per cent of HA users and 51% of non-operated CI candidates had troublesome tinnitus. CIs were found to be superior to HAs in reducing tinnitus, 54% of the CI patients with tinnitus experiencing a reduction in tinnitus when using a CI. In the other two groups, 4% of HA users and 23% of non-operated CI candidates experienced a reduction in tinnitus when using an HA. Eight per cent of the CI patients with tinnitus experienced an increase in tinnitus when using their implant. Not having paid employment was independently associated with troublesome tinnitus in all three groups.

Tinnitus suppression in patients with cochlear implants

OBJECTIVE

To determine the degree of tinnitus suppression provided by currently available multichannel cochlear implants and to determine factors that can influence this process.

STUDY DESIGN

Prospective cohort.

SETTING

Tertiary-care referral center.

PATIENTS

Thirty-eight adult patients (18 years of age or older) with severe-to-profound hearing loss and tinnitus who met criteria for cochlear implantation.

INTERVENTION

Cochlear implantation with a multichannel cochlear implant device.

MAIN OUTCOME MEASURES

Patients rated the intensity of their tinnitus using a semiquantitative scale before and after cochlear implantation. These data were analyzed to determine the significance of the reduction of tinnitus after implantation. Tinnitus levels after implantation were also analyzed to determine whether the level of speech recognition, patient gender, or the implant type influenced the degree of tinnitus reduction.

RESULTS

Statistical analysis revealed a significant reduction in tinnitus intensity in patients using cochlear implants, with 35 of 38 patients (92%) experiencing a reduction in tinnitus intensity. All multichannel implants studied afforded similar degrees of tinnitus suppression. The degree of tinnitus reduction was not correlated with speech recognition, as measured by CID Everyday Sentence scores. Female patients had significantly greater degrees of tinnitus before implantation, but both male and female patients demonstrated similar levels of tinnitus after implantation. No patient experienced greater levels of tinnitus after implantation.

CONCLUSION

All currently available multichannel cochlear implant devices provide effective and similar levels of tinnitus suppression when activated. Exacerbation of tinnitus as a result of cochlear implantation does not represent a significant risk. The mechanisms by which cochlear implants exert tinnitus suppression are, as yet, unclear.

Somatic (craniocervical) tinnitus and the dorsal cochlear nucleus hypothesis

PURPOSE

Of all nonauditory sensory systems, only the somatosensory system seems to be related to tinnitus (eg, temporomandibular joint syndrome and whiplash). The purpose of this study is to describe the distinguishing characteristics of tinnitus associated with somatic events and to use these characteristics to develop a neurological model of somatic tinnitus.

MATERIALS AND METHODS

Case series.

RESULTS

Some patients with tinnitus, but no other hearing complaints, share several clinical features including (1) an associated somatic disorder of the head or upper neck, (2) localization of the tinnitus to the ear ipsilateral to the somatic disorder, (3) no vestibular complaints, and (4) no abnormalities on neurological examination. Pure tone and speech audiometry of the 2 ears is always symmetric and usually within normal limits. Based on these clinical features, it is proposed that somatic (craniocervical) tinnitus, like otic tinnitus, is caused by disinhibition of the ipsilateral dorsal cochlear nucleus. Nerve fibers whose cell bodies lie in the ipsilateral medullary somatosensory nuclei mediate this effect. These neurons receive inputs from nearby spinal trigeminal tract, fasciculus cuneatus, and facial, vagal, and glossopharyngeal nerve fibers innervating the middle and external ear.

CONCLUSIONS

Somatic (craniocervical) modulation of the dorsal cochlear nucleus may account for many previously poorly understood aspects of tinnitus and suggests novel tinnitus treatments.

Retest stability of the tinnitus handicap questionnaire

The test-retest stability of the Tinnitus Handicap Questionnaire was assessed for a sample of 32 tinnitus patients. The questionnaire is a self-report measure that quantifies the physical, emotional, and social consequences of tinnitus (factor 1), the interfering effects of tinnitus on the hearing ability of the patient (factor 2), and the patients' view of tinnitus (factor 3). Retest stability estimates were obtained in order to determine the applicability of using the questionnaire as an outcome measure following tinnitus management. High test-retest correlations emerged for factors 1 and 2, whereas factor 3 yielded inadequate retest reliability. Therefore, it is recommended that only factors 1 and 2 be used for documenting changes in self-perceived tinnitus handicap following medical, surgical, or rehabilitative intervention.