Transcranial magnetic stimulation for tinnitus: using the Tinnitus Functional Index to predict benefit in a randomized controlled trial

Sequential Multilocus Repetitive Transcranial Magnetic Stimulation for Treatment of Tinnitus With and Without Comorbid Major Depressive Disorder

OBJECTIVE

Repetitive transcranial magnetic stimulation (rTMS) is a promising treatment for tinnitus, although outcomes are highly variable. We previously described a multilocus sequential rTMS treatment protocol for tinnitus involving stimulation of both prefrontal and auditory targets. In this study, we report results using this approach in an open-label treatment study of tinnitus with and without comorbid major depressive disorder (MDD).

MATERIALS AND METHODS

Forty patients with chronic tinnitus (mean age 56 years, ten female) and with (n = 17) or without (n = 23) MDD received multilocus rTMS administered sequentially to 1) left dorsolateral prefrontal cortex, followed by 2) auditory cortex (Heschel's gyrus). Patients completed weekly self-report ratings using the Tinnitus Functional Index (TFI) and Tinnitus Handicap Inventory, and patients with MDD completed the Inventory of Depressive Symptomatology Self-Report 30-item.

RESULTS

Patients showed significant mean improvement in tinnitus at sessions 5 (mean TFI improvement 6.8 points ± 12.2, p = 0.002) and 10 (mean improvement 9.2 points ± 14.1, p = 0.002), with 48% of patients responding within ten treatment sessions. Responders were significantly older than nonresponders (61.5 ± 15 years vs 51.3 ± 16 years), and there was a trend toward decreased likelihood of response in subjects with comorbid MDD compared with subjects without comorbidity (odds ratio = 0.28, p = 0.06). Patients with comorbid MDD reported significantly less improvement after ten sessions than did those with tinnitus alone (4.3 ± 10.3 vs 14.7 ± 15.0 points, p = 0.04). Post hoc analyses suggested that the comorbid group achieved improvement comparable to that of the tinnitus-only group after 30 treatments.

CONCLUSIONS

Patients showed significant improvement in tinnitus from multilocus sequential rTMS treatment, and those with tinnitus alone improved more quickly. Those with depression who continued rTMS through a full 30-session course further improved, indicating that tinnitus with comorbid MDD may respond with extended treatment.

Sequential Prefrontal and Temporoparietal Repetitive Transcranial Magnetic Stimulation (rTMS) for Treatment of Tinnitus With and Without Comorbid Depression: A Case Series and Systematic Review

Background

Tinnitus distress is related to both the loudness and intrusiveness of the tinnitus percept. Treatment approaches targeting both attentional/limbic and auditory systems may better alleviate tinnitus distress than approaches targeting the auditory system alone.

Materials and Methods

Ten subjects with chronic tinnitus received sequential rTMS treatment involving: 1) excitatory stimulation administered to the left dorsolateral prefrontal cortex (DLPFC) or inhibitory stimulation administered to the right DLPFC, followed by 2) inhibitory stimulation administered to primary auditory cortex (Heschel's gyrus or HG). A systematic literature review was performed to evaluate the existing literature on sequential repetitive Transcranial Magnetic Stimulation (rTMS) treatment approaches for tinnitus. Results of the case series are interpreted in the context of tinnitus neurobiology and the extant literature.

Results

Subjects experienced a significant decrease (average 21.7%) in symptoms on the Tinnitus Functional Index (TFI). Those with tinnitus alone experienced a greater mean symptom reduction than those with comorbid MDD (27.7 vs. 17.0%, respectively). Adverse effects were transient and minor. Literature review confirmed that sequential approaches had some advantages compared to single site rTMS; in general, the addition of 1 Hz treatment at DLPFC was superior to single site rTMS in the short term (1-12 weeks), while the addition of 20 Hz treatment at DLPFC appeared superior in the long term (90-180 days).

Conclusions

Sequential rTMS approaches for the treatment of tinnitus-particularly those administering low-frequency treatment at left DLPFC-merit further investigation.

Audiometric Characteristics and Tinnitus Features in a Cohort of 170 Spanish Patients

BACKGROUND

Tinnitus is a rather prevalent, quite heterogeneous, and difficult to treat auditory disorder. The aim of this article is to provide the design and results of a cross-sectional study related to audiological and tinnitus features in a group of 170 Spanish patients.

METHODS

Audiometric characteristics were assessed on the basis of the pure-tone audiometry of both ears in 170 tinnitus patients and 85 control subjects. The audiometric status of each tinnitus participant was assessed on the basis of the average auditory threshold (AAT) in the whole frequency range (from 125 Hz to 8 kHz), and low (from 125 Hz to 2 kHz) and high (from 3 kHz to 8 kHz)-frequency intervals. Tinnitus features were evaluated through personal interview with patients and included tinnitus duration, laterality, pitch, sound, and distress (Tinnitus Handicap Inventory, THI). Correlational analysis was carried out between audiological (AAT) and tinnitus (THI) variables.

RESULTS

A very weak Spearman rank correlation factor is found between both variables.

CONCLUSIONS

The subjective outcome of tinnitus distress (THI) was not correlated with the objective measure of hearing loss (AAT) in our cohort.

Methodological Aspects of Randomized Controlled Trials for Tinnitus: A Systematic Review and How a Decision Support System Could Overcome Barriers

Although a wide range of tinnitus management interventions is currently under research and a variety of therapeutic interventions have already been applied in clinical practice, no optimal and universal tinnitus treatment has been reached yet. This fact is to some extent a consequence of the high heterogeneity of the methodologies used in tinnitus related clinical studies. In this manuscript, we have identified, summarized, and critically appraised tinnitus-related randomized clinical trials since 2010, aiming at systematically mapping the research conducted in this area. The results of our analysis of the 73 included randomized clinical trials provide important insight on the identification of limitations of previous works, methodological pitfalls or gaps in current knowledge, a prerequisite for the adequate interpretation of current literature and execution of future studies.

Electrophysiological correlates of focused attention on low- and high-distressed tinnitus

OBJECTIVES

The study aimed at determining the EEG correlates of concentration on either low or high-distressed tinnitus.

METHODS

Sixty-seven patients (36 women, mean age = 50.34 ± 12.94 years) with chronic tinnitus were assigned to either a high (HD) or low (LD) tinnitus-related distress group based on THI results. All participants took part in the EEG study comprising two 3-4 min blocks of focusing on either tinnitus (Tinnitus Focus Condition, TFC) or the sensations from one's own body (Body Focus Condition, BFC). The absolute power and current density of 8 frequency bands in 7 clusters were compared between conditions and groups.

RESULTS

The most pronounced differences were found in the HD patients in the TFC, relative to the BFC, i.e. reduced power of frontally distributed low alpha (8-10 Hz) and posterior high alpha (10-12 Hz) as well as lower current density of 8-10 Hz rhythm over the right frontal/anterior cingulate cortex and higher middle beta (15-18 Hz) density in the precuneus. The HD, relative to LD patients, in both conditions, exhibited increased low beta (12-15 Hz) power over the left middle area and greater higher beta (15-25 Hz) power in the left posterior region.

CONCLUSIONS

The present study contrasted bioelectrical activity, acquired when concentrating on tinnitus with EEG data collected whilst patients focused on their body. Decreased alpha power and current density in the frontal/cingulate cortex when listening to bothersome tinnitus might reflect greater cortical arousal whereas increased beta power and density in the precuneus/posterior cingulate activity in this condition could be indicative for elevated tension or augmented cognitive/emotional processing of tinnitus sound. Enhanced beta rhythm in patients with high versus low tinnitus distress, observed independently of the study condition, may be due to greater self-focused attention or more active processing of sensations derived from the own body.

Comparison of Tinnitus Loudness Measures: Matching, Rating, and Scaling

Purpose Chronic tinnitus ("ringing in the ears") is a phantom auditory perception with no cure. A goal of treatment is often to reduce the loudness of tinnitus. However, tinnitus loudness cannot be measured objectively. It is most commonly assessed by obtaining a loudness match (LM) with a pure tone and by using a numeric rating scale (NRS). Constrained loudness scaling (CLS) is a more recent measure of tinnitus loudness that utilizes auditory training of a fixed loudness scale to guide tinnitus loudness judgments. The purpose of this study was to compare results using these 3 measures of tinnitus loudness. Method This study obtained tinnitus loudness measures of LM, NRS, and CLS with 170 participants. These participants are part of a larger study obtaining repeated measures over 6 months. Only baseline data are presented. Results Correlations between all measures were weak to moderate: LM versus CLS ( r = .46), CLS versus NRS ( r = .49), and LM versus NRS ( r = .38). Conclusion Further systematic research is needed to more fully understand the relationships between these different measures and to establish a valid measure of tinnitus loudness.

Randomized Controlled Trial of a Novel Device for Tinnitus Sound Therapy During Sleep

PURPOSE

The aim of this study was to determine if a customized stimulus from the Otoharmonics Levo System reduces tinnitus perceptions and reactions for people with bothersome tinnitus.

METHOD

Sixty participants were randomized to 1 of 3 groups that used sound therapy devices during sleep that differed in their acoustic stimulus: (a) tinnitus-matched (TM), (b) noise stimulus (NS), and (c) bedside sound generator (BSG). Outcome measures were the Tinnitus Functional Index (TFI), numeric rating scale of tinnitus loudness, and tinnitus loudness match. A Bayesian hierarchical model was fit to estimate the differences in treatment efficacy among groups.

RESULTS

Average tinnitus reactions and perceptions improved across treatment groups. We are at least 87% certain that treatment with TM or NS reduces mean TFI compared to treatment with BSG, with an estimated relative efficacy of 4.5-5 points greater reduction. We are at least 95% certain that treatment with TM results in greater reduction in mean numeric rating scale (NRS) of tinnitus loudness compared to the other groups, with an estimated relative efficacy of about 0.75 points greater reduction.

CONCLUSIONS

This study offers some support for greater average improvement in reactions to tinnitus with TM or NS devices compared to the BSG device. The TM group, compared to the BSG and NS groups, showed a greater reduction in ratings of tinnitus loudness on the NRS on average.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.5545759.