Tinnitus after cochlear implantation

Complications after cochlear implantation in adult patients: a retrospective study

OBJECTIVE

To examine the complication rate in adult patients during and after cochlear implantation.

METHODS

A retrospective chart review was conducted of patients who had undergone cochlear implantation at a tertiary referral centre between 2009 and 2018. All complications and their treatments were categorised as either minor or major, as well as intra- or post-operative.

RESULTS

The records of 392 patients with 395 implants were reviewed. The mean follow-up period was 89 ± 65.5 months (range, 6-408 months). The mean age of patients was 46 ± 15.2 years (range, 19-84 years). Sixty-two patients (16 per cent) had minor complications and 31 (8 per cent) had major complications.

CONCLUSION

Although cochlear implantation has the potential for significant intra- and post-operative complications, the actual complication rate is relatively low, and it can therefore be considered a safe procedure.

The effects of dietary and physical activity interventions on tinnitus symptoms: An RCT

OBJECTIVE

Subjective tinnitus is defined as the perception of irregular sound at different frequencies. Although the underlying cause of tinnitus is unclear, increased body weight is known to increase tinnitus symptoms. The present study aimed to determine the effects of dietary and physical activity interventions on tinnitus symptoms.

METHODS

Sixty-three obese subjects with tinnitus aged 20 to 65 years were divided into diet + physical activity (P.A.) (n = 15), diet (n = 16), P.A. (n = 15), and control (n = 17) groups. Dietary records, anthropometric measurements, Tinnitus Handicap Inventory (THI), Beck Depression Inventory (BDI), Short-Form Health Survey (SF-36), and Visual Analogue Scale (VAS) of all individuals were recorded and compared at the baseline and at study completion.

RESULTS

Body weight decreased in the diet + P.A. (-5.9 (3.5) kg), diet (-3.4 (0.9) kg), and P.A. (-2.0 (2.1) kg) groups compared to the baseline (p < 0.05). There was a more significant decrease in tinnitus frequency, tinnitus severity, and VAS scores in individuals with a weight loss of ≥ 5.0% than in those with < 5.0% (p < 0.05). A decrease of 1 kg/m² in BMI decreased the BDI score by 0.485 units and the THI score by 0.523 units. Step counts were increased in the diet + P.A. (3562.3±739.9) and P.A. (3797.1 ± 1801.1) groups compared to baseline (p < 0.01). Each increase of 1000 steps increased the SF-36 score by 1.592 units and decreased the THI score by 0.750 units (p < 0.05).

CONCLUSION

Dietary and physical activity interventions, alone or in combination, alleviated tinnitus symptoms and increased quality of life in individuals with tinnitus. Due to its contribution to obesity prevention and positive effects on tinnitus, organizing dietary and physical activity programs for obese individuals with tinnitus would improve these individuals' quality of life.

Changes in Tinnitus by Cochlear Implantation: A Parametric Study of the Effect of Single-Electrode Stimulation

INTRODUCTION

While cochlear implantation may have a positive effect on tinnitus, it is not effective in reducing tinnitus in all patients. This may be due to different patients requiring different strategies of electrical stimulation in order to obtain a positive effect on tinnitus. It is, therefore, important to identify the most effective stimulation strategies to reduce tinnitus. The simplest possible strategy is stimulation by only one electrode. In this study, we investigated tinnitus suppression by electrical stimulation via a single electrode of the cochlear implant.

METHODS

We performed a listening experiment in 19 adult participants, who had received a unilateral cochlear implant (CI) because of severe bilateral hearing loss. All of these patients had indicated that they suffered from tinnitus. During a 300-s interval, patients listened to blocks of single-electrode stimulation and rated the loudness of the stimulus and any effects on their tinnitus. The 300-s interval included a block of single-electrode stimulation (duration 120 s). In consecutive intervals, the stimulus differed in its cochlear location (basal or apical), its pulse rate (720 or 725 Hz, 1,200 Hz, and 2,400 or 2,320 Hz), and amplitude (just above threshold or equivalent to moderate loudness). Thus, 2 × 3 × 2 = 12 stimulus conditions were tested in each participant, and each condition was presented only once. During the experiment, the participants promptly rated the loudness of the stimuli and the loudness of their tinnitus on a Visual Analogue Scale (10-point VAS).

RESULTS

Significantly more tinnitus reduction was observed with stimuli at a moderate intensity level (30%) compared to stimuli at near-threshold level (18%) (χ2 [1, N = 222] = 14.115, p < 0.01). No significant differences in tinnitus levels resulted from the different pulse rates and stimulation sites. Eight participants reported an increase of tinnitus loudness under at least one stimulus condition. Changes in tinnitus loudness were generally minor, and never exceeded 3 points on the VAS. The overall effect of cochlear implantation on tinnitus, that is, the effect with full-array stimulation, was not correlated with the effectiveness of the single-electrode stimulation on tinnitus.

CONCLUSION

In conclusion, the effect of single-electrode stimulation on tinnitus is relatively insignificant in comparison to the effect of full-array stimulation. However, in some individual cases, sustained single-electrode stimulation may be beneficial for tinnitus management.

Age-related hearing loss and tinnitus, dementia risk, and auditory amplification outcomes

Age-related hearing loss (ARHL) or presbycusis, as the third leading cause of chronic disability in older adults, has been shown to be associated with predisposing cognitive impairment and dementia. Tinnitus is also a chronic auditory disorder demonstrating a growth rate with increasing age. Recent evidence stands for the link between bothersome tinnitus and impairments in various aspects of cognitive function. Both ARHL and age-related tinnitus affect mental health and contribute to developing anxiety, stress, and depression. The present review is a comprehensive multidisciplinary study on diverse interactions among ARHL, tinnitus, and cognitive decline in older adults. This review incorporates the latest evidence in prevalence and risk factors of ARHL and tinnitus, the neural substrates of tinnitus-related cognitive impairments, hypothesized mechanisms concerning the association between ARHL and increased risk of dementia, hearing amplification outcomes in cases with ARHL and cognitive decline, and preliminary findings on the link between ARHL and cognitive impairment in animal studies. Given extensive evidence that demonstrates advantages of using auditory amplification in the alleviation of hearing handicap, depression, and tinnitus, and the improvement of cognition, social communication, and quality of life, regular hearing screening programs for identification and management of midlife hearing loss and tinnitus is strongly recommended.

A Prospective Study of the Effect of Cochlear Implantation on Tinnitus

Previous studies have shown diverse and sometimes even contrary results concerning the effect of cochlear implantation on tinnitus and the factors that can influence this effect. The aim of this prospective questionnaire study was to determine the effects of cochlear implantation on tinnitus and explore which factors can influence the effect of cochlear implantation on tinnitus. Forty-four of the patients implanted in our hospital returned 2 questionnaire packages, i.e., one before the cochlear implantation and one 6 months after implantation. Before implantation, 66% of the patients experienced tinnitus. This study shows that cochlear implantation could help to reduce tinnitus and the tinnitus handicap in at least 28% of the patients with preoperative tinnitus. In 72% of the patients the tinnitus remained after implantation. None of the patients developed tinnitus after implantation. A shorter duration of tinnitus prior to implantation, a more fluctuating type of tinnitus, a higher tinnitus handicap prior to implantation, and a round-window surgical approach might have a positive influence on the effect of cochlear implantation on tinnitus, but further research is necessary to confirm these findings.

Changes in Tinnitus after Cochlear Implantation and Its Relation with Psychological Functioning

This study retrospectively assessed the prevalence of tinnitus in cochlear implant patients and the changes after implantation in 212 patients implanted between 2000 and 2009. Patients were included at least 6 months after implantation and received 2 sets of questionnaires, one about the situation before implantation and one about the situation after implantation. Mostly standardized questionnaires assessed tinnitus handicap (Tinnitus Handicap Inventory, THI, and Tinnitus Handicap Questionnaire, THQ), tinnitus characteristics, hearing loss (Abbreviated Profile of Hearing Aid Benefit) and anxiety/depression (Hospital Anxiety and Depression Scale). Of the approached patients, 117 completed the full sets of questionnaires and 35 completed a short version. Preoperative tinnitus was reported by 51.3% of these patients, of which 55.6% reported a reduction or cessation of their tinnitus after implantation. However, 8.2% of the patients with tinnitus reported a postoperative deterioration of their tinnitus. In addition, among the patients without preoperative tinnitus, 19.6% reported the start of tinnitus after implantation. The self-reported change of tinnitus correlated with the pre- and postoperative scores on the THI and THQ. The THQ showed slightly more changes in scores after cochlear implantation compared to the THI. Overall hearing handicap and feelings of anxiety and depression decreased after implantation. In conclusion, tinnitus is reduced after cochlear implantation in an important part of the patients, but in a small part implantation has a negative effect on tinnitus. When tinnitus starts after implantation, the tinnitus handicap is mild.

Surgical approaches to tinnitus treatment: A review and novel approaches

Background:

Tinnitus, a profoundly widespread auditory disorder, is characterized by the perception of sound in the absence of external stimulation. The aim of this work is to review the various surgical treatment options for tinnitus, targeting the various disruption sites along the auditory pathway, as well as to indicate novel neuromodulatory techniques as a mode of tinnitus control.

Methods:

A comprehensive analysis was conducted on published clinical and basic neuroscience research examining the pathophysiology and treatment options of tinnitus.

Results:

Stereotactic radiosurgery methods and microvascular decompressions are indicated for tinnitus caused by underlying pathologies such as vestibular schwannomas or neurovascular conflicts of the vestibulocochlear nerve at the level of the brainstem. However, subsequent hearing loss and secondary tinnitus may occur. In patients with subjective tinnitus and concomitant sensorineural hearing loss, cochlear implantation is indicated. Surgical ablation of the cochlea, vestibulocochlear nerve, or dorsal cochlear nucleus, though previously suggested in earlier literature as viable treatment options for tinnitus, has been shown to be ineffective and contraindicated. Recently, emerging research has shown the neuromodulatory capacity of the somatosensory system at the level of the trigeminal nerve on the auditory pathway through its inputs at various nuclei in the central auditory pathway.

Conclusion:

Tinnitus remains to be a difficult disorder to treat despite the many surgical interventions aimed at eliminating the aberrant neuronal activity in the auditory system. A promising novel neuromodulatory approach using the trigeminal system to control such a bothersome and difficult-to-treat disorder deserves further investigation and controlled clinical trials.