Tinnitus Treatments
Number: 0406
(Replaces CPB 478)
Table Of Contents
PolicyApplicable CPT / HCPCS / ICD-10 Codes
Background
References
Policy
Scope of Policy
This Clinical Policy Bulletin addresses treatments for tinnitus.
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Medical Necessity
Aetna considers the following interventions medically necessary:
- Cognitive behavioral therapy (CBT) when all of the following criteria are met:
- Diagnosis of persistent (6 months or more) tinnitus; and
- Treatable causes have been ruled out (e.g., cerumen impaction, ear infection, vascular pathology, ototoxic medications, Meniere's disease, acoustic neuroma); and
- Tinnitus is causing clinically significant distress or functional impairment (e.g., sleep disturbance, impaired concentration, emotional distress, reduced quality of life); and
- CBT is administered by a licensed mental health professional (e.g., psychologist, psychiatrist, clinical social workers, licensed counselor, and mental health nurses) trained in CBT; or
- Cortical mastoidectomy and restoration of separation between the sigmoid sinus and middle ear for tinnitus resulting from bony defect in the mastoid/temporal bone (described as sigmoid sinus dehiscence or sigmoid sinus wall dehiscence, and sometimes caused by sigmoid diverticulum), when a bony defect with dehiscence of the sigmoid sinus is documented on imaging of the temporal bone;
- Cognitive behavioral therapy (CBT) when all of the following criteria are met:
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Experimental, Investigational, or Unproven
Aetna considers the following interventions experimental, investigational, or unproven because the effectiveness of these approaches has not been established:
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Tinnitus instruments (e.g., maskers, hearing aids, or combination of maskers and hearing aids) for the management of members with tinnitus because the effectiveness of these instruments has not been demonstrated in randomized controlled studies with large sample size and long-term follow-up evaluation;
Note: Tinnitus instruments such as maskers and hearing aids are approved by the Food and Drug Administration (FDA) and are classified as Class III devices; however, tinnitus masking is not approved for coverage by the Centers for Medicare & Medicaid Services (CMS).
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The following interventions for the management of members with tinnitus (not an all-inclusive list):
- Acoustic coordinated reset neuromodulation
- Acupuncture
- Audiotherapy (e.g., acoustic stimulation and auditory perceptual training)
- BeyondTinnitus system
- Bi-modal stimulation (acoustic stimulation and transcutaneous auricular vagus nerve stimulation for the treatment of tonal tinnitus)
- Cochlear implants
- Competitive kinesthetic interaction therapy (KKIT)
- Cortical stimulation
- Deep brain stimulation
- DNA (daytime-nighttime appliance) oral appliance therapy
- Ear canal magnets
- Electromagnetic stimulation (including transcranial magnetic stimulation)
- Extra-cochlear electrical stimulation
- Eye movement desensitization and reprocessing (EMDR)
- Hyperbaric oxygen therapy
- Intra-cranial venous sinus stenting
- Intra-tympanic administration of corticosteroids
- Intravenous lidocaine
- Intravenous mexiletine
- Lenire device (bi-modal neuromodulation)
- Lidocaine iontophoresis
- Low-level laser therapy (also known as photobiomodulation)
- Lysis of middle ear tendons
- Microvascular decompression of the cochlea-vestibular nerve
- Music therapy
- Neurofeedback
- Neuromonics Tinnitus Treatment/Neuromonics Oasis device
- Noise/sound generators
- Oxytocin
- Ozone therapy
- Peripheral muscle magnetic stimulation
- Radiofrequency lesion of the superior cervical sympathetic ganglion (including pulsed radiofrequency of C2 dorsal root ganglion)
- Repetitive transcranial magnetic stimulation (including continuous theta burst stimulation)
- Sequential phase shift sound cancellation treatment
- Sound therapy (including the Otoharmonics Levo System sound therapy)
- Tinnitus retraining therapy
- Topographical filter dermal patch
- Transcranial electrical neuromodulation (e.g., alternating current stimulation, direct current stimulation, and random noise stimulation)
- Transcutaneous electrical nerve stimulation (TENS)
- Transmeatal laser irradiation (low-level laser)
- Vagus nerve stimulation
- Vitamin B12 injections.
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Related Policies
- CPB 0011 - Peripheral Electrical Nerve Stimulation for Pain
- CPB 0013 - Cochlear Implants and Auditory Brainstem Implants
- CPB 0034 - Aural Rehabilitation
- CPB 0113 - Botulinum Toxin
- CPB 0132 - Biofeedback
- CPB 0135 - Acupuncture and Dry Needling
- CPB 0172 - Hyperbaric Oxygen Therapy (HBOT)
- CPB 0191 - Vagus Nerve Stimulation
- CPB 0238 - Chronic Vertigo
- CPB 0363 - Cold Laser and High-Power Laser Therapies
- CPB 0469 - Transcranial Magnetic Stimulation and Cranial Electrical Stimulation
- CPB 0514 - Meniere's Disease and Related Disorders: Surgery
- CPB 0536 - Vitamin B-12 Therapy
- CPB 0583 - Eye Movement Desensitization and Reprocessing (EMDR) Therapy
- CPB 0856 - Embolization: Selected Procedures
Background
Tinnitus is a clinical symptom characterized by the perception of sound in the absence of an external acoustic stimulus, commonly described as ringing, buzzing, hissing, roaring, or clicking. It is not a disease entity itself but rather a manifestation of underlying auditory, neurologic, vascular, metabolic, or pharmacologic conditions. Tinnitus is broadly classified as subjective (perceived only by the patient and accounting for the vast majority of cases) or objective (rare and audible to an examiner, typically related to vascular or muscular sources). It may also be categorized as primary (idiopathic), often associated with sensorineural hearing loss and age- or noise-related cochlear dysfunction, or secondary, when attributable to an identifiable and potentially treatable cause such as otologic disease, temporomandibular joint disorders, vascular anomalies, or intracranial pathology. Clinically, tinnitus is further described as pulsatile (synchronous with the heartbeat and suggestive of vascular etiologies) or non‑pulsatile, which is more commonly neuro‑sensory in origin. Because the pathophysiology of tinnitus is multifactorial and incompletely understood, a wide range of therapeutic interventions has been explored in the medical literature.
Subjective tinnitus, which is more common, is audible only to the patient. It may arise from some types of electrophysiological disturbance anywhere in the auditory system – the external ear canal, tympanic membrane, ossicles, cochlea, auditory nerve, brainstem or cerebral cortex. The underlying causes of subjective tinnitus include otological (presbycusis, noise-induced hearing loss, Meniere's disease, or chronic otitis media), metabolic (diabetes, thyroid diseases, hyperlipidemia, or zinc deficiency/vitamin deficiency), pharmacological (aspirin compounds, non-steroidal anti-inflammatory drugs, caffeine, nicotine, aminoglycosides, or antidepressants), neurological (whiplash, skull fracture/closed head trauma, multiple sclerosis, or following meningitis), psychological (depression or anxiety), as well as infectious and neoplastic (syphilis, acoustic neuroma, autoimmune diseases, or acquired immune deficiency syndrome) disorders.
Objective tinnitus, the less common type of tinnitus, usually refers to noises that can be heard by an examiner. The physician must put his/her ear against the patient's ear or use a stethoscope against the patient's external auditory canal. Objective tinnitus usually has a vascular (arteriovenous malformations/shunts, arterial bruits, hypertension, arteriosclerosis, venous hums, or aneurysms) or mechanical (Eutaschian tube dysfunction, temporomandibular joint disease, palatal myoclonus, or idiopathic stapedal muscle spasm) origin (Schuler and Schleuring, 1994; Seidman and Jacobson, 1996).
Although there is currently no cure for primary tinnitus, a wide range of therapies has been used and studied in attempts to provide symptomatic relief. These therapies include education and counseling, auditory therapies that include hearing aids and specific forms of sound therapy, cognitive behavioral therapy (CBT), medications, dietary changes and supplements, acupuncture, and transcranial magnetic stimulation (TMS). Secondary tinnitus is tinnitus that is associated with a specific underlying cause (other than sensorineural hearing loss [SNHL]) or an identifiable organic condition. It is a symptom of a range of auditory and nonauditory system disorders that include simple cerumen impaction of the external auditory canal, middle ear diseases such as otosclerosis or Eustachian tube dysfunction, cochlear abnormalities such as Ménière's disease, and auditory nerve pathology such as nonauditory system disorders that can cause tinnitus (e.g., vascular anomalies, myoclonus, intracranial hypertension). Management of secondary tinnitus is targeted toward identification and treatment of the specific underlying condition (Tunkel et al., 2014).
The American Academy of Otolaryngology - Head and Neck Surgery Foundation (AAO/HNS) (Tunkel et al., 2014) provide the following recommendations for tinnitus management:
- Hearing aid evaluation for patients with hearing loss and persistent, bothersome tinnitus (C: observational studies, Recommendation)
- Cognitive behavioral therapy (CBT) for patients with persistent, bothersome tinnitus (A: high-quality randomized controlled trials (RCTs), Recommendation)
- Clinicians should not routinely recommend antidepressants, anticonvulsants, anxiolytics, or intratympanic medications for a primary indication of treating persistent, bothersome tinnitus (B: consistent RCTs, Recommendation).
- Clinicians should not recommend Ginkgo biloba, melatonin, zinc, or other dietary supplements for treating patients with persistent, bothersome tinnitus (C: observational studies, Recommendation).
- No recommendation can be made regarding the effect of acupuncture in patients with persistent bothersome tinnitus.
- Clinicians should not recommend transcranial magnetic stimulation (TMS) for the routine treatment of patients with persistent, bothersome tinnitus (B: consistent RCTs, Recommendation).
Sherlock et al. (2025) emphasize that the updated US Department of Veterans Affairs (VA) and the US Department of Defense (VA/DoD) Clinical Practice Guideline for tinnitus represents a rigorously developed, evidence‑based framework that replaces the 2014 guideline, yet is notably constrained by the quality of the underlying evidence. Using the GRADE methodology across four evidence domains, the Work Group issued predominantly weak or neither‑for‑nor‑against recommendations, reflecting the paucity of high‑quality randomized controlled trials and pervasive methodological limitations. The guideline supports, with weak strength, the use of validated patient‑reported outcome measures for monitoring, educational counseling, hearing aids in adults with hearing loss, cochlear implantation in appropriate candidates, therapeutic sound use, cognitive behavioral therapy (alone or combined with sound‑based interventions), and multidisciplinary management for patients with comorbid somatic conditions (e.g., temporomandibular disorders or cervical dysfunction). Conversely, it suggests against psychoacoustic monitoring measures, low‑level laser therapy, ginkgo biloba and other supplements, and multiple pharmacologic agents, including anticonvulsants, antidepressants, betahistine, intratympanic corticosteroids, and NMDA antagonists. For a wide range of commonly used or emerging interventions—such as app‑based self‑management, altered music therapy, auditory cognitive training, neurostimulation techniques (e.g., repetitive transcranial magnetic stimulation [rTMS], transcranial direct current stimulation [tDCS], transcutaneous electric nerve stimulation [TENS]), acupuncture, and several amplification strategies—the evidence was deemed insufficient to support recommendations for or against use. Collectively, the guideline highlights both the maturity of the evidence appraisal process and the persistent gaps in interventional tinnitus research, resulting in cautious, conditional guidance rather than strong clinical directives.
In addition to the AAO/HNS and VA/DoD recommendations, CBT has been found to have stronger evidential support over transcutaneous electrical nerve stimulation (TENS) for tinnitus management. CBT is the only treatment with moderate- to high-quality evidence for reducing tinnitus distress, while TENS has very low-certainty evidence with insufficient data to support a recommendation. CBT teaches skills to identify negative thoughts that result in distress and restructure them to be more accurate or helpful, and includes behavioral interventions such as relaxation techniques, exposure to feared stimuli, sleep hygiene instruction, and auditory enrichment. The guidelines notes that several systematic reviews suggest a beneficial effect of CBT for tinnitus patients, with CBT showing significant improvement in depression associated with tinnitus and quality of life (decrease of global tinnitus severity), though no effect on subjective tinnitus loudness was found. Additionally, CBT was found to be more effective than behavioral treatments alone, with sustained benefits on tinnitus-specific outcome measures and smaller benefits for mood outcomes. Treatment typically consists of an 8-week program delivered by a trained professional (Bauer, 2018; Byun et al., 2020; Chen et al., 2026; Dalrymple et al., 2021;Fuller et al., 2020; Sherlock et al., 2025).
Chen et al. (2026) conducted a PRISMA‑compliant umbrella review of 44 systematic reviews with meta‑analyses (including 9 Cochrane reviews) encompassing multiple tinnitus interventions across seven domains, synthesizing evidence from studies published through April 2025. Outcomes focused on validated measures of tinnitus severity, distress, loudness, quality of life, and related psychological comorbidity, with methodological quality assessed using AMSTAR‑2 (27/44 reviews rated “critically low”). Psychological and behavioral therapies showed the most consistent and highest‑quality evidence overall, particularly cognitive behavioral therapy (CBT), which demonstrated reproducible moderate improvements in tinnitus distress and severity across multiple meta‑analyses (SMD −0.44 to −1.46), along with benefits for insomnia and mood; CBT was also the most extensively studied intervention with relatively lower heterogeneity. Tinnitus retraining therapy (TRT) showed one of the largest pooled clinical responses (OR 7.86, p < 0.00001; THI MD −14.50) but requires substantial time and resources. Acceptance and commitment therapy (ACT) produced large reductions in distress (THI MD −17.67) and anxiety (SMD −0.79), though evidence remains less mature. Among device‑based therapies, hearing aids achieved large pooled effects (SMD −1.21 to −1.38), while cochlear implantation yielded the largest absolute THI reductions observed overall (up to −29.97) but with very high heterogeneity (>90%) and applicability limited to patients with severe hearing loss. Acupuncture showed statistically significant improvements in composite efficacy (OR 3.16; RR 1.25) and THI (SMD −1.34) but faced limitations related to blinding and variability in study quality. Neuromodulation (TMS, tDCS, TENS) produced small‑to‑moderate benefits with inconsistent durability, and pharmacologic interventions largely failed to show clinically meaningful effects. Limitations included substantial overlap among reviews, heterogeneous outcome measures and protocols, predominance of short‑term follow‑up, reliance on self‑reported outcomes, and generally low methodological quality. In summary, CBT had the strongest and most consistent evidence base, while cochlear implantation showed the greatest magnitude of benefit in appropriately selected patients.
Acoustic Coordinated Reset Neuromodulation
Wegger and colleagues (2017) noted that there are growing technological advances in the development of sound-based methods for the treatment of tinnitus. Most of these methods intend to affect the speculated underlying neurological causes of tinnitus. Acoustic coordinated reset (CR) neuromodulation is a novel method that, as of yet, seems inadequately reviewed. These investigators evaluated the current evidence on acoustic CR neuromodulation as a method for the treatment of tinnitus and examined if the method can be implemented in daily clinical practice. They performed a systematic literature search in 13 databases in the period from February 1, 2015, to May 1, 2016. Studies regarding acoustic CR neuromodulation as a treatment method for tinnitus were included in the present review. A total of 8 studies were eligible for review, comprising a total of 329 patients. Overall, the evidence level of the published literature was low. The main findings in the included studies were that acoustic CR neuromodulation was safe and well-tolerated, and most patients reported a reduction of tinnitus symptoms. The neurophysiological basis of the method was claimed to be desynchronization, anti-kindling, and change of abnormal frequency couplings in a widespread tinnitus network comprising both auditory and non-auditory brain areas based on electroencephalographic (EEG) analyses. The authors concluded that the available evidence is insufficient for the clinical implementation of acoustic CR neuromodulation. They stated that the limited level of evidence suggested that acoustic CR neuromodulation may have positive effects on tinnitus symptoms. The authors noted that these preliminary EEG data are compatible with the claim that tinnitus reduction after CR treatment is mediated by a desynchronizing effect; however, proof for this claim is still lacking.
Haller and Hall (2017) noted that the therapeutic effects of coordinated reset (CR) neuromodulation were originally discovered by researchers at the Forschungzentrum Juelich GmbH (FZJ) in Germany. Acoustic CR neuromodulation is designed as a patient-specific targeted sound therapy. The treatment has been provided to over 3,000 patients worldwide to date. Several peer-reviewed papers have reported a reduction of tinnitus symptoms (from baseline) in populations of tinnitus sufferers by using a portable acoustic neurostimulator providing acoustic CR neuromodulation; including tinnitus loudness measured using a VAS. Neuronal synchrony and pathological synaptic connectivity result in a substantial and long-lasting reduction of disease symptoms. In October 2011, Nottingham University Hospitals NHS Trust agreed to conduct an investigator-led evaluation of acoustic CR neuromodulation versus placebo effects, recruiting 100 participants with a 1:1 allocation ratio (the RESET 2 Trial). Participants were adults aged 18 years or older, with chronic subjective tinnitus for more than 3 months, a minimum score of 18 points measured using the Tinnitus Handicap Inventory (THI), a dominant tinnitus pitch corresponding to a frequency between 0.2 and 10 kHz, and an average hearing loss no greater than 60 dB (0.5, 1, 2, and 4 kHz). The formal results of the RESET 2 trial were non-conclusive, which was unexpected, considering the past and current volumes of observational data showing substantial benefit. The authors concluded that controlled trials to test the clinical effectiveness of acoustic CR neuromodulation for tinnitus are worthwhile. With the knowledge gained from the RESET 2 trial, it is suggested that future trials should include a placebo or "usual standard of care" control group that is well characterized, should follow a well-defined and trained pitch matching protocol, should assess the status of tinnitus for longer than 12 weeks (these researchers suggested at least 6 months), should better control the baseline characteristics to avoid floor and ceiling effects, and should use an outcome instrument with known measurement properties for the target population.
Acupuncture
Acupuncture is the technique of inserting and manipulating very fine needles into the skin to stimulate specific anatomic points in the body for therapeutic purposes.
The American Academy of Otolaryngology - Head and Neck Surgery Foundation’s clinical practice guideline on "Tinnitus" (2014) stated that no recommendation can be made regarding the effect of acupuncture in patients with persistent bothersome tinnitus.
Liu and colleagues (2016) performed a systematic review and meta-analysis of all available randomized controlled trials (RCTs) using acupuncture to treat tinnitus. A total of 5 electronic databases, in both English and Chinese, were searched. All studies in this review and meta-analysis included parallel RCTs of tinnitus patients, which compared subjects receiving acupuncture (or its other forms, such as electro-acupuncture) to subjects receiving no treatment, sham treatment, drugs, or basic medical therapy. Data from the articles were validated and extracted using a predefined data extraction form. Nearly all of the Chinese studies reported positive results, while most of the English studies reported negative results. Analysis of the combined data found that the acupuncture treatments appeared to provide some advantages over conventional therapies for tinnitus. There were differences in acupuncture points and sessions between Chinese studies and English studies. Methodological flaws were also found in many of the RCTs, especially in the Chinese studies. The authors concluded that the findings of this review suggested that acupuncture therapy may offer subjective benefits to some tinnitus patients. They noted that the acupuncture points and sessions used in Chinese studies may be more appropriate; however, these studies have many methodological flaws and risks of bias, which prevented them from making a definitive conclusion.
He et al. (2016) examined the effect of electro-acupuncture for alleviating the symptoms of subjective tinnitus. These researchers performed literature searches in 3 English and 4 Chinese databases (PubMed, EMBASE, Cochrane Library, CNKI, Wanfang Chinese Digital Periodical and Conference Database, VIP, and ChiCTR). The date of the most recent search was June 1, 2014. Randomized controlled trials or quasi-RCTs were included. The titles, abstracts, and keywords of all records were reviewed by 2 authors independently; the data were collected and extracted by 3 authors. The risk of bias in the trials was assessed in accordance with the Cochrane Handbook, version 5.1.0. A total of 89 studies were retrieved; after discarding 84 articles, 5 studies with 322 subjects were identified. Assessment of the methodological quality of the studies identified weaknesses in all 5 studies. All studies were judged as having a high risk of selection and performance bias. The attrition bias was high in 4 studies. Incompleteness bias was low in all studies. Reporting bias was unclear in all studies. Because of the limited number of trials included and the various types of interventions and outcomes, these researchers were unable to conduct pooled analyses. The authors concluded that due to the poor methodological quality of the primary studies and the small sample sizes, no convincing evidence that electro-acupuncture is beneficial for treating tinnitus could be found. There is an urgent need for more high-quality trials with large sample sizes for the investigation of electro-acupuncture treatment for tinnitus.
In a RCT, Laureano and associates (2016) examined the effect of acupuncture on brain perfusion using ethyl cysteinate dimer single-photon emission computed tomography (99mTc-ECD SPECT) in patients with tinnitus. This randomized, single-blind, sham-controlled study examined patients (18 to 60 years old) with normal hearing and chronic idiopathic tinnitus (CIT). A total of 57 subjects were randomly assigned to true (n = 30) or sham (n = 27) acupuncture (ACP); 99mTc-ECD SPECT examinations were performed before and after 12 twice-weekly ACP sessions. Secondary outcomes included changes in the Tinnitus Handicap Inventory (THI), Visual Analog Scale (VAS), Hamilton Anxiety Scale (HAS), and Beck Depression Inventory (BDI). Imaging data were analyzed using Statistical Parametric Mapping (SPM8) software. Regression models were used to examine secondary outcomes via 2 paradigms: intention-to-treat (ITT; where multiple imputations were conducted because of study attrition) and complete cases. No between-group brain perfusion differences were observed. However, a significant improvement in THI scores was observed at the end of true ACP treatment for all domains (all p-values < 0.01) except the catastrophic scale. The authors concluded that ACP might reduce the effects of tinnitus on daily life; however, additional studies should be conducted to verify the effects of ACP on the neural architecture and brain function of tinnitus patients.
Chen and Jing (2025) noted that no single treatment is considered to be universally effective for tinnitus; scalp acupuncture has been examined as a potential treatment. In a systematic review and meta-analysis, these researchers examined the effectiveness of scalp acupuncture in the treatment of tinnitus. They carried out a comprehensive search of relevant databases to identify RCTs comparing scalp acupuncture with a control treatment for tinnitus. The clinical efficacy rate, as well as the reduction in tinnitus severity, were evaluated using relative risk (RR) and standardized mean difference (SMD), respectively. Sensitivity analyses were conducted to assess sources of heterogeneity. A total of 20 studies (1,430 subjects) were included. The systematic review and meta-analysis showed that the scalp acupuncture groups had a significantly higher clinical effective rate compared to the control groups (RR = 1.25, 95% CI: 1.16 to 1.35, p < 0.00001), with low heterogeneity (p = 0.27, I² = 20%). The scalp acupuncture groups and scalp acupuncture plus auxiliary acupoints groups had greater reductions in tinnitus severity compared to the control groups (SMD = -0.76, 95% CI: -1.02 to -0.51, p < 0.00001; SMD = -0.93, 95% CI: -1.52 to -0.33, p = 0.002, respectively), with moderate heterogeneity (p = 0.005, I² = 62%) and significant heterogeneity (p < 0.00001, I² = 86%) observed due to differences in study design, sample characteristics, and intervention protocols. Sensitivity analysis confirmed the stability of the results. The summary table generated via GRADEpro indicated that the certainty of evidence ranged from moderate to low. The authors concluded that scalp acupuncture has demonstrated promising effectiveness in the treatment of tinnitus compared to traditional acupuncture or pharmacotherapy; however, the available evidence is limited due to potential biases and heterogeneity across studies. These researchers stated that further investigations with standardized protocols, higher methodological rigor, and long-term effectiveness are needed to validate these findings.
Auditory Perceptual Training
Hoare et al. (2010) stated that auditory perceptual training affects neural plasticity and so represents a potential strategy for tinnitus management. These investigators assessed the effects of auditory perceptual training on tinnitus perception and/or its intrusiveness via a systematic review of published literature. An electronic database search using the keywords 'tinnitus and learning' or "tinnitus and training" was conducted, updated by a hand search. The 10 studies identified were reviewed independently by 2 reviewers, data were extracted, study quality was assessed according to a number of specific criteria and the information was synthesised using a narrative approach. Nine out of the 10 studies reported some significant change in either self-reported or psychoacoustic outcome measures after auditory training. However, all studies were quality rated as providing low or moderate levels of evidence for an effect. The authors identified a need for appropriately randomized and controlled studies that will generate high-quality unbiased and generalisable evidence to ascertain if auditory perceptual training has a clinically relevant effect on tinnitus.
BeyondTinnitus System
BeyondTinnitus is a customized tinnitus rehabilitation strategy. Unlike using a generic white noise or sound from hearing aids, the sound therapy provided by BeyondTinnitus supposedly aids in directing the sound to the area of the brain most responsible for one’s tinnitus. Based on protocols developed at the University of California, BeyondTinnitus is designed to provide users with harmonic sound therapy to provide relief.
Mahboubi et al (2012a) examined the accuracy of a web-based protocol for tinnitus frequency matching compared to that of tinnitus pitch matching conducted by an audiologist using an audiometer in an anechoic chamber. A total of 20 subjects underwent tinnitus frequency-matching in a random order using an audiometer in an anechoic chamber and using web-based software with a multiple-choice protocol in octave or half-octave steps from 250 Hz to 12,000 Hz, and a slider in 25-Hz steps from 20 to 20,000 Hz. Octave challenge testing was performed. Participants were asked to indicate which protocol resulted in the closest match to their tinnitus frequency. The median tinnitus frequency was 6,000 Hz (range of 2,000 to 12,000 Hz) with use of the audiometer and self-directed multiple-choice protocol. With the slider, the median frequency was 5,925 Hz (range of 1,850 to 16,000 Hz). Subjects with a tinnitus frequency higher than 12,000 Hz experienced a greater level of satisfaction when using the computer-based slider system; 5 subjects experienced octave confusion with self-directed multiple-choice tinnitus matching that was corrected accurately after the octave challenge step. The authors concluded that a web-based protocol for tinnitus frequency matching was as accurate as a standard audiometric protocol. An octave challenge test might be necessary for patient-directed tinnitus frequency matching. The authors stated that the findings of this trail should be interpreted with consideration of its drawbacks. The validity of the matches could not be evaluated since there is no way to directly measure a phantom sensation. This study was also limited by a small sample size (n = 20). These researchers stated that future studies with larger sample sizes and repeated measures are needed to further evaluate web-based protocols for tinnitus pitch matching.
Mahboubi et al (2012b) stated that traditional masking efforts have presented broad-band noises, most typically white noise. Targeted (customized) sound therapies have been introduced to overcome the limitations of traditional maskers. These researchers examined the effectiveness of a web-based delivery of customized sound therapy in reducing tinnitus loudness and increasing the residual inhibition. A total of 32 subjects matched their tinnitus frequency using a web-based protocol. A customized Harmonic Sound Therapy file was produced by the web-based software and down-loaded by the patient onto an MP3 player. The subjects listened to the sound file for 1 hour. Tinnitus loudness mean was 6.0 ± 2.3 standard deviation (SD), which decreased to 3.3 ± 1.9 SD after 1 hour of sound therapy. Some reduction in loudness was reported in 81 %, while 72 % experienced a reduction of 25 % or more. Tinnitus annoyance decreased from an average of 6.1 ± 2.6 SD to 3.1 ± 2.0 SD. Median duration of residual inhibition was 32.5 mins, with an average of 75 mins ± 132 SD. The authors conclude that customized sound therapy could be delivered via the internet. Harmonic Sound Therapy was effective in reducing the loudness and annoyance of tinnitus.
Mahboub et al (2017) examined the effectiveness of a customized sound therapy and compared its effectiveness to that of masking with broad-band noise. Subjects were randomized to receive either customized sound therapy or broad-band noise for 2 hours per day for 3 months, and then switched to the other treatment after a washout period. The outcome variables were tinnitus loudness (scored 0 to 10), THI, BAI, minimum masking levels (MML), and residual inhibition (RI). A total of 18 subjects completed the study. Mean age was 53 ± 11 years, and mean tinnitus duration was 118 ± 99 months. With customized sound therapy, mean loudness decreased from 6.4 ± 2.0 to 4.9 ± 1.9 (p = 0.001), mean THI decreased from 42.8 ± 21.6 to 31.5 ± 20.3 (p < 0.001), mean BAI decreased from 10.6 ± 10.9 to 8.3 ± 9.9 (p = 0.01), and MML decreased from 22.3 ± 11.6 dB SL to 17.2 ± 10.6 dB SL (p = 0.005). After 3 months of broad-band noise therapy, only BAI and, to a lesser degree, MML decreased (p = 0.003 and 0.04, respectively). The authors concluded that customized sound therapy could decrease the loudness and THI scores of tinnitus patients, and the results may be superior to broad-band noise.
The authors stated that this study had several drawbacks. First, the lack of improvement in the subjects’ tinnitus, worsening of the tinnitus, and the inability to maintain the benefit achieved in the sound therapy. These might have partially contributed to the follow-up losses and drop-outs. The stimulation may not reduce the tinnitus, which may result in psychological distress such as anxiety or depression. Given significant reduction in the QOL in tinnitus sufferers, administration of acoustic stimulus via head-phones was a very small risk that was far out-weighed by the possibility of suppressing the tinnitus. The 3-scale nature of the THI questionnaire may limit its sensitivity to perform a question-by-question analysis compared to 100-scale questionnaires. However, it is a validated questionnaire that has been used in various tinnitus studies. Second, the long-term nature of the study and the number of tests conducted on each subject, which required a significant amount of time dedicated by the subjects and made it difficult to achieve high numbers for enrollment. The time commitment for the follow-up visits precluded 2 of the subjects to finish the study as their employment status changed during the study. Third, contralateral presentation of sound stimuli for audiometric pitch matching was used as a part of the psycho-acoustic assessments of the subject. This technique may occasionally yield different pitch matches between the ear due to binaural diplacusis. However, the soft-ware used binaural presentation for pitch matching to create the sound files. The randomization of the starting arm and the washout period were considered to account for any possible carrying effect from one treatment to the other. Overall, the randomized and cross-over design of this clinical trial provided a unique opportunity to examine the long-term outcomes of customized sound therapy and compare them to those of non-customized therapy.
Abouzari et al (2021) developed a smartphone application providing sound therapy and CBT for treating tinnitus and carried out a proof-of-concept (POC) pilot study examining its potential effectiveness. These researchers developed an interactive smartphone application available on iOS and Android platforms, which provided an 8-week tinnitus-specific CBT and personalized and frequency-matched sound therapy. Included patients presented to the authors’ tertiary clinic between 2017 and 2018, while those on the waiting list were regarded as controls. A total of 3 surveys were administrated: THI, Generalized Anxiety Disorder 7-item (GAD-7), and Perceived Stress Scale (PSS). A total of 30 patients enrolled in this study consisting of 20 treatment and 10 control patients; mean age was 55.4 ± 11.6 years. Treatment and control patients had similar age, sex, and pre-enrolment GAD and PSS (all p > 0.05). Baseline THI scores were also similar between treatment and control cohorts (50.1 ± 21.9 versus 62.0 ± 20.7; p = 0.15). After 8 weeks, though changes in GAD and PSS scores were similar (p > 0.05), the treatment group reported a significantly greater improvement in THI scores (17.7 ± 15.8 versus 5.3 ± 10.5, p = 0.04). The authors concluded that the findings of this pilot study showed potentially promising effectiveness of a smartphone-based CBT and sound therapy platform for treating tinnitus; future RCTs with larger sample sizes are needed to examine the psycho-social effectiveness of such application-delivered management for patients with tinnitus..
The authors stated that this study had several drawbacks including selection bias, small patient cohorts, and lack of extensive evaluation of quantitative or qualitative outcomes. These researchers stated that the change in THI warrants further investigation of this platform’s potential efficacy. Besides the low sample size, this pilot study was limited based on patient selection and the lack of randomization of the participants into the 2 groups. The trial was also limited by the level of scaling and analysis to determine/compare tinnitus severity. Another drawback was a lack of patients’ clinical history of auditory masking, which could be important when examining which group of patients were more susceptible to improvement from sound therapy. This was significant because patients’ auditory masking may be the most significant predictor of the level of therapeutic effectiveness that could be received from customized sound therapy. To address this, these researchers would continue investigating this program, and implement Feldmann H masking evaluation to associate it with the sound therapy’s relative masking effect. Tinnitus and its effect on people can be uniquely individualized in other ways as well, making the proposed program more suitable for certain patients compared to the others. Due to these drawbacks, the findings may not be generalized to the general population until further investigations of such mobile applications with appropriate methodologies are applied. Future studies should also collect and analyze THI questionnaire’s subscale scores beyond this manuscript’s reported total score. With the positive feedback from participants and the promising results of the pilot study, this report will be followed by a proper randomized controlled clinical trial. By investigating detailed tinnitus-related and behavioral questionnaires before and after the program, these investigators could assess specific factors associated with program responsiveness, and which patients would be most likely to improve.
Furthermore, an UpToDate review on “Treatment of tinnitus” (Dinces, 2024) does not mention BeyondTinnitus / customized sound therapy as a management option.
Bi-Modal Stimulation for the Treatment of Tonal Tinnitus
Bolandi et al stated that the dorsal cochlear nucleus (DCN) is the interaction site of auditory and somatosensory system inputs. According to the stochastic resonance theory, hearing loss increases the neural activity of the somatosensory system in the DCN and causes tinnitus. it is possible to modulate this neural hyperactivity by using random noise via the auditory as well as the somatosensory systems (bi-modal stimulation). These investigators examined the effectiveness of the bi-modal intervention based on the theory of stochastic resonance. This trial divided 34 subjects into uni-modal and bi-modal groups with 17 participants in each group. The bi-modal group received customized acoustic stimulation along with transcutaneous auricular vagus nerve stimulation (tAVNS) and the uni-modal group received customized acoustic stimulation along with tAVNS as a sham. The treatment sessions in both groups were 6 sessions and each session lasted for 20 mins. Participants were examined before, immediately after, and 1 month after the completion of the intervention sessions, using the THI questionnaire and the mismatch negativity (MMN) test. After the intervention sessions, the results indicated a statistically significant decrease in THI scores and a significant increase in the MMN amplitude in the bi-modal group compared to the uni-modal group. No significant changes in MMN latency were observed between the 2 groups. These changes were stable in the 1-month follow-up visit. The authors concluded that the findings of this study demonstrated that bi-modal stimulation was a better therapeutic option compared to uni-modal stimulation. These researchers stated that bi-modal stimulation may be an effective treatment for some patients with tinnitus, especially those with hearing loss who have tonal tinnitus.
Cochlear Implant
A cochlear implant is a surgically implanted electronic device that can provide improved speech and hearing communication abilities for people who have severe to profound hearing loss in both ears. Purportedly, the device may help tinnitus by masking with ambient sound or by suppression when electrical stimulation is sent through the auditory nerve.
ao and Chen (2012) evaluated the effects of cochlear implantation (CI) on ipsilateral tinnitus. With a standard assessment table and standard testing program, 48 post-lingual hearing-impaired adults aged 18 to 62 years (mean age at implantation: 35.0) were operated on at 5 clinical centers from June 2009 to March 2010. There were 23 males (47.9%) and 25 females (52.1%). These researchers evaluated the pre- and post-implantation degrees of tinnitus, performed free sound field audiometry, and scored speech perception during different periods. Secondary analyses were conducted to examine the correlation between the effects of implantation on tinnitus and hearing or speech perception rehabilitation. Before implantation, there were 16 cases with ipsilateral tinnitus and 32 cases without tinnitus. After implantation, among the 16 cases, the outcomes were recovery (n = 6), tinnitus suppression (n = 1), and no change in symptoms (n = 9). The total effective rate was 43.8%. Among the other 32 cases without pre-operative tinnitus, 2 cases developed tinnitus after implantation. The effects of CI on tinnitus were negatively correlated with the course of tinnitus. There was no further correlation with other factors. The authors concluded that CIs have significant therapeutic effects on tinnitus in 43.8% of implant users. Better efficacy is correlated with a shorter course of tinnitus. However, they stated that tinnitus suppression using electrical stimulation via CI for deafness needs to be further evaluated.
Tavora-Vieira et al. (2013) examined the effectiveness of CI in patients with unilateral deafness with and without tinnitus. A total of 9 post-lingually deafened subjects with unilateral hearing loss, with and without ipsilateral tinnitus, and functional hearing in the contralateral ear were implanted with a standard electrode. Speech perception in noise was tested using the Bamford-Kowal-Bench presented at 65 dB SPL. The Speech, Spatial, and Qualities (SSQ) of Hearing Scale was used to evaluate the subjective perception of hearing outcomes, and the Tinnitus Reaction Questionnaire assessed the effect on tinnitus. All patients were implanted with the Med-El Flex soft electrode, Innsbruck, Austria. They were regularly wearing the speech processor and found it beneficial in improving their ability to hear, particularly in noise. Decreases in tinnitus perception and improvements in sound localization were also reported by these patients. The authors concluded that in this case series, CI was successful for all 9 patients, with improvements in speech recognition in noise, self-perceived improvement of hearing, and tinnitus control. Moreover, they stated that several factors such as deafness duration, age of deafness onset, the presence of residual hearing, patient motivation, and rehabilitation intensity need to be further investigated to understand their impact on performance after implantation. (It is unclear how many of the 9 patients had tinnitus.)
In a review on "Cochlear implantation for single-sided deafness: The outcomes. An evidence-based approach," Vlastarakos et al. (2014) reviewed the current evidence on the effectiveness of CI as a treatment modality for SSD and/or unilateral tinnitus. A systematic literature review in Medline and other database sources was conducted along with a critical analysis of pooled data. The study selection included prospective and retrospective comparative studies, case series, and case reports. The total number of analyzed studies was 17. A total of 108 patients with SSD have been implanted; 66 patients due to problems associated with SSD, and 42 primarily because of debilitating tinnitus. Cochlear implantation in SSD leads to improved sound localization performance and speech perception in noise from the ipsilateral side with an angle of coverage up to (but not including) 90° to the front when noise is present in the contralateral quartile (Strength of recommendation B). Speech and spatial hearing also subjectively improve following the insertion of a CI (Strength of recommendation B); this was not the case regarding the quality of hearing. Tinnitus improvement was also reported following implant placement (Strength of recommendation B); however, patients need to be advised that the suppression is mainly successful when the implant is activated. The overall quality of the available evidence supports a wider use of CI in SSD following appropriate selection and counseling (overall strength of recommendation B). It remains to be seen if the long-term follow-up of a large number of patients in well-conducted high-quality studies will confirm the above-mentioned results.
Blasco and Redleaf (2014) noted that in recent years, otologists have begun to place cochlear implants into non-functioning ears after sudden unilateral hearing loss. Patients in these trials demonstrated differing degrees of hearing loss in the un-implanted ear. Few studies have examined the role of implantation in patients with normal hearing in the un-implanted ear. These researchers reviewed the available literature to understand if this practice benefits these patients in terms of tinnitus, sound localization, and speech understanding. Medline, Embase, and Cochrane databases were searched for publications from database inception to June 1, 2013, without restriction of language. A search of multiple medical databases was performed to identify articles reporting case series of CI for unilateral hearing loss. Subjects were included for analysis only if the course of hearing loss was acute and rapidly progressive, if the loss was severe to profound, and if the contralateral ear had normal hearing. A total of 9 appropriate articles were identified, in which 36 patients met the inclusion criteria. Three meta-analyses were performed: of tinnitus (22 patients); of the lowest signal-to-noise ratio, which still allowed 50% sentence understanding (16 patients); and of sentence understanding at a fixed signal-to-noise ratio (12 patients). They found that measures of tinnitus reduction and decreased signal-to-noise ratios that still allowed 50% speech discrimination were statistically significantly reduced. A systematic review of subjective changes in tinnitus in 27 patients, speech understanding in 16 patients, and sound localization in 16 patients found 96%, 100%, and 87% improvements, respectively. The authors concluded that CI in unilateral sudden hearing loss with a normally functioning contralateral ear might prove to be an effective therapy. Tinnitus is reduced, as is the signal-to-noise ratio, which still allows 50% speech discrimination. All patients felt that they localized sound better, and most felt that they understood speech better. They stated that further studies should be conducted to compare the success of hearing rehabilitation of CI and traditional modalities such as contralateral routing of signal and bone-anchored hearing aids.
Furthermore, an August 2013 Agency for Healthcare Research and Quality’s comparative effectiveness review on "Evaluation and treatment of tinnitus" (Pichora-Fuller et al., 2013) indicated that the use of cochlear implants for tinnitus and single-sided deafness is a very recent off-label indication and indicated insufficient evidence for the use of this and other sound therapies for tinnitus.
Cognitive Behavioral Therapy
Cognitive behavioral therapy (CBT) is a structured, time‑limited psychotherapeutic intervention that focuses on identifying and modifying maladaptive thought patterns, emotional responses, and behaviors. In the context of tinnitus, CBT does not aim to eliminate the auditory perception itself, but rather to reduce tinnitus‑related distress by reframing negative cognitive appraisals, decreasing maladaptive coping behaviors, and improving emotional regulation. CBT addresses the central role of attentional focus, catastrophic thinking, anxiety, and depression in perpetuating tinnitus severity and functional impairment.
Wood and Theodoroff (2019) highlight that CBT has consistently proven to be an effective method for helping patients manage tinnitus distress. While there is no universal agreement on the optimal approach for tinnitus management, clinical practice guidelines offer a comprehensive review of current strategies, along with supporting or opposing evidence. CBT for tinnitus has received endorsements from the American Academy of Audiology, the American Academy of Otolaryngology–Head and Neck Surgery Foundation, and the American Speech-Language-Hearing Association as a valid treatment option. Typically, CBT consists of 6 to 10 weekly sessions, conducted either individually or in small groups, with each session focusing on specific topics such as tinnitus education, sleep hygiene, stress management, relaxation techniques, and cognitive restructuring. The therapy process is personalized to address the unique needs of each patient, but it generally emphasizes goal-oriented problem-solving, the evaluation and modification of dysfunctional thoughts, and the alteration of negative behavior patterns.
Fuller et al. (2020) reported that tinnitus affects up to 21% of adults, with 1% to 3% experiencing severe issues. Cognitive behavioral therapy (CBT), a psychological treatment approach, is often used to help those suffering from tinnitus. The study aimed to evaluate the effects and safety of CBT for adults with tinnitus. The Cochrane ENT Information Specialist conducted a comprehensive search of various medical databases for published and unpublished trials up to November 25, 2019, focusing on randomized controlled trials (RCTs) comparing CBT to no intervention, audiological care, tinnitus retraining therapy, or other active treatments. The analysis followed standard Cochrane procedures, assessing primary outcomes related to the impact of tinnitus on quality of life and serious adverse effects, along with secondary outcomes such as depression, anxiety, and health-related quality of life. The review included 28 studies with 2,733 participants, primarily from Europe, who had experienced tinnitus for at least three months, with CBT durations ranging from 3 to 22 weeks, mostly conducted in hospitals or online.
Their findings indicated that CBT may reduce the impact of tinnitus on quality of life compared to no intervention, with a standardized mean difference (SMD) of -0.56, suggesting a clinically meaningful improvement. Serious adverse effects were minimal, with no significant differences reported. CBT also showed a slight reduction in depression but had uncertain effects on anxiety and health-related quality of life. When compared to audiological care, CBT likely improved quality of life, with a mean difference of -5.65 on the Tinnitus Handicap Inventory (THI). The evidence suggested that CBT may reduce negatively biased interpretations of tinnitus but had limited impact on other outcomes. In a comparison with tinnitus retraining therapy, CBT also appeared to improve quality of life, although the evidence was of low certainty. Among other active controls, CBT may reduce the impact of tinnitus on quality of life, with some evidence of reduced depression and anxiety. The authors concluded that while CBT may effectively lessen the negative impact of tinnitus on quality of life, evidence at 6 and 12 months follow-up is lacking, and further investigation into potential adverse effects is warranted. Overall, the evidence for CBT's effectiveness in improving anxiety, health-related quality of life, or negatively biased interpretations of tinnitus remains limited.
Sherlock et al. (2025) report that the VA/DoD Work Group conducted a systematic review of the evidence supporting the use of cognitive behavioral therapy (CBT) for tinnitus management, but expressed very low confidence in the quality of this evidence. The limitations identified in the body of evidence included small sample sizes, broad confidence intervals, and imprecision in effect sizes. Despite these limitations, the benefits of CBT—such as reduced tinnitus distress, improved quality of life, and alleviation of related conditions like anxiety, depression, and insomnia—were found to outweigh the minimal potential harms associated with adverse events. However, patient values and preferences varied, as access to behavioral and mental health practitioners is inconsistent, and some patients favored shorter treatment options. Consequently, the Work Group recommends CBT delivered by a trained provider for adults experiencing bothersome tinnitus.
Xian et al. (2025) aimed to compile and assess evidence from meta-analyses and systematic reviews regarding tinnitus treatment to provide a reference for clinical decision-making in managing this condition. The researchers conducted searches in major medical databases, including CNKI, PubMed, Embase, Web of Science, and the Cochrane Library, collecting literature on systematic reviews and meta-analyses related to tinnitus treatment without language restrictions. They evaluated the methodological quality, reporting quality, and evidence quality of the included studies using the Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR-2), the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool. Ultimately, 48 out of 2,642 screened publications met the eligibility criteria, focusing on primary treatment modalities such as tinnitus counseling, cognitive behavioral therapy (CBT), auditory therapy, tinnitus retraining therapy (TRT), and pharmacotherapy. The analysis covered seven treatment approaches, with three showing definitive efficacy and four demonstrating probable efficacy. The authors found that CBT demonstrated the strongest and most consistent benefit, with Grade A evidence and a strong recommendation as first-line therapy due to significant improvements in treatment response and tinnitus severity scores. TRT showed moderate efficacy with Grade B evidence, while music therapy demonstrated neuroplastic benefits with symptom reduction but lower-quality (Grade C) evidence. Cochlear implantation was effective for selected patients with unilateral sensorineural hearing loss and tinnitus. Non-invasive brain stimulation techniques, pharmacologic agents, acupuncture, and traditional Chinese medicine demonstrated variable or modest efficacy, but were limited by heterogeneity, side effects, or low methodological quality and thus are not broadly recommended at this time. Other modalities, including e-health interventions, hyperbaric oxygen, hearing aids, and laser therapy, lacked sufficient evidence. Overall, the review emphasizes CBT, with selective use of adjunctive therapies based on individual patient characteristics, while highlighting gaps in long-term outcomes and the need for higher-quality, methodologically robust studies to inform durable clinical recommendations.
Competitive Kinesthetic Interaction therapy (KKIT)
Competitive kinesthetic interaction therapy (KKIT) is adapted physiotherapy using expressive movements of body language. Different groups of muscles in the hand, arm, leg, foot and body, from the feet up to the face, are activated, which purportedly guides the patient into a situation of peaceful resting, reduction of tension and finally into relaxation. This scheme was adapted from a rehabilitation program for treating pain. There is a lack of reliable evidence for KKIT for treatment of tinnitus.
Cortical Stimulation
Deklerck and colleagues (2020) noted that although the prevalence and burden of tinnitus is high, none of the available tinnitus treatments has been proven to be effective for the majority of tinnitus patients so far. Neuromodulation is currently gaining more interest to explore as tinnitus treatment. Because non-invasive neuromodulation has been shown to be effective in some tinnitus patients in the short-term, more invasive techniques have been applied with variable success and without clear clinical applicability. As new insights into the neuro-pathophysiology of tinnitus arise, it appeared essential to recapitulate the current evidence of invasive neuromodulation for tinnitus, to evaluate the quality of the available studies and identify gaps in this research domain. Data sources included Medline, Embase, Web of Science and Clinical Trial Register. These researchers carried out a systematic review following the PRISMA statement. Studies since 2005 that reported on adult human subjects with chronic subjective tinnitus, who underwent some form of invasive neuromodulation, were included. Quality evaluation was conducted using the modified Downs and Black checklist. A total of 21 studies were included. Studies were often of low-quality due to small sample sizes, lack of controlled designs, or examining tinnitus as a secondary indication of neuromodulation. The authors concluded that current research results provided insufficient evidence to generally recommend invasive neuromodulation as an alternative treatment for intractable tinnitus, although some promising effects were mentioned. These researchers stated that further research is needed to gain more insight in this treatment including optimization of the technique, and standardization of tinnitus evaluation in subgroups. Key words in the review included cortical stimulation, and deep brain stimulation.
Deep Brain Stimulation
In a case series with chart review, Shi et al. (2009) reported deep brain stimulation (DBS) effects in patients with tinnitus. A total of 7 patients implanted with deep brain stimulation (DBS) systems for movement disorders who also reported having tinnitus were interviewed about their tinnitus conditions. Four were available for testing in a specialized tinnitus clinic with their DBS systems turned off or on. Testing included matching of self-rated and psychoacoustically measured tinnitus loudness to measure the impact of DBS on tinnitus; 3 of the 7 patients reported reduced tinnitus loudness when DBS was turned on. Of the 4 patients tested in the clinic, results indicated that DBS of the ventralis intermedius nucleus of the thalamus caused decreases in tinnitus loudness in 2 patients with relatively prolonged residual inhibition. The authors concluded that these results suggested that DBS of non-auditory thalamic structures may provide tinnitus relief for some patients. These preliminary findings need to be validated by well-designed studies.
Cheung and Larson (2010) reported that the application of DBS therapy to a locus of caudate neurons (area LC) can decrease or increase tinnitus loudness perception. The DBS lead traversed through or was adjacent to area LC in 6 Parkinson's disease and essential tremor subjects with concomitant tinnitus who underwent implantation of the subthalamic or ventral intermediate nucleus. In 5 subjects where the DBS lead tip traversed area LC, tinnitus loudness in both ears was suppressed to a nadir of level 2 or lower on a 0 to 10 rating scale. In 1 subject where the DBS lead was outside area LC, tinnitus was not modulated. In 3 subjects with pre-operative and post-operative audiograms, hearing thresholds were unchanged by area LC stimulation. Neuromodulation of area LC may be interrupting the perceptual integration of phantom sensations generated in the central auditory system. The authors stated that this new, basal ganglia-based approach to tinnitus modulation warrants further investigation and may ultimately be refined to treat patients with refractory symptoms.
DNA (Daytime-Nighttime Appliance) Oral Appliance Therapy
The DNA appliance is a removable oral appliance that stretches the upper arches of one’s teeth. This allows for room for the tongue to occupy without blocking your airway; it is designed for the treatment of obstructive sleep apnea. There is a lack of evidence regarding the effectiveness of DNA oral appliance for the treatment of tinnitus.
An UpToDate review on “Treatment of tinnitus” (Dinces, 2024) does not mention the use of oral appliance as a management option.
Ear Canal Magnets and Electromagnetic Stimulation
A systematic evidence review published in BMJ Clinical Evidence (Savage et al., 2009; Savage et al., 2011) concluded that the effectiveness of ear canal magnets and electromagnetic stimulation for tinnitus is unknown.
The systematic evidence review identified two small randomized controlled clinical trials comparing electromagnetic stimulation to placebo. The first trial (n = 58) found that 15 minutes per day of electromagnetic stimulation significantly increased the proportion of people who reported subjective improvements in tinnitus compared to placebo after one week (citing Roland et al., 1993). Based on subjective responses assessed by a 4-point questionnaire, 14 of 31 subjects assigned to electromagnetic stimulation improved compared to 2 of 23 subjects assigned to placebo (p = 0.0013). The systematic review noted that 4 subjects withdrew from the trial and that the analysis was not conducted by intention to treat. A second randomized controlled clinical trial (n = 20) used a crossover design and did not report results before the crossover (citing Dobie et al., 1986). The crossover trial found similar effects between electromagnetic stimulation and a placebo device in reducing tinnitus severity. Severity, measured on a scale of 0-7, was reported as less severe in 2 of 20 subjects with the active device versus 3 of 20 subjects with the placebo device.
The systematic evidence review found one randomized controlled clinical trial (n = 49) that reported similar effects between a simple ear-canal magnet and placebo (similar unmagnetized material) on tinnitus symptoms after 4 weeks of treatment (citing Coles et al., 1991). Symptom improvement was reported in 7 of 26 persons with the magnet compared to 4 of 23 persons with placebo.
Electrical Stimulation / Transcutaneous Electrical Nerve Stimulation (TENS)
Another therapeutic modality is electrical stimulation (ES). Electrical stimulation may include placing electrodes directly on the bony cochlea or the round window niche (one of two openings that connect the inner ear to the middle ear) or anywhere in the vicinity of the ear. The exact mechanism by which electrical stimulation is proposed to reduce tinnitus is unclear.
In a review on tinnitus, Siedman and Jacobson (1996) indicated that ES is a possible treatment modality for patients with severe tinnitus. Hatton et al. (1960) reported that only anodal (positive electrode) stimulation produced the suppressive effect. In general, ES is provided through electrodes in the vicinity of the ear. The exact mechanism(s) by which ES suppresses or reduces tinnitus is unclear. However, it has been postulated that positive electrical currents produce a hyperpolarization of nerve fibers, which inhibits and reduces spontaneous discharge rates (Portmann et al., 1983).
Hatton et al. (1960) observed that the intensity of tinnitus was reduced in 15 (45.5%) of 33 patients with ES. Chouard et al. (1981) reported that 30 (47%) of 64 patients achieved success (as determined by reduced intensity that lasted for a few days to more than 1 week) following electrotherapy. None of the 12 patients who received placebo stimulation attained relief. The authors stated that if a patient failed to achieve improvement after 2 to 3 sessions, it is unlikely that this form of therapy will be successful.
Engelberg and Bauer (1985) performed two experiments to examine the effects of transcutaneous electrical stimulation (TENS) on tinnitus. Experiment 1 had 10 subjects (18 ears), and improvement (defined as either a complete remission or a decrease in the frequency of tinnitus) was seen in 6 of them, with tinnitus being eliminated in 3 ears. Experiment 2 employed a single-blind study design with 20 patients (experimental group, n = 10, 17 ears; control group, n = 10, 15 ears). It was found that 9 of 10 patients with 15 (88.2%) of 17 ears reported improvement following stimulation. These changes lasted from 20 minutes to at least 6 months. On the other hand, only 1 patient (1 ear) in the control group improved (a 13% decrease in frequency of tinnitus).
Steenerson and Cronin (1996) reported their findings of 246 patients with severe tinnitus of various etiologies treated with ES (a total of 6 to 10 sessions). One hundred and thirty patients (53%) reported significant benefit (an improvement of at least 2 points on a 1 to 10 subjective rating scale), with 32 patients (13%) having complete suppression of their tinnitus. At the 3-month follow-up, 72% had continuous benefit.
In a subsequent report, Steenerson and Cronin (1999) reported their findings in 500 patients with tinnitus who were treated with probe electrical stimulation. The authors reported that 53% of patients showed decreases in their tinnitus as measured by a subjective rating scale. At the 3-month follow-up, 72% had no loss of benefit.
Rahko and Kotti (1997) treated 26 patients with transcutaneous nervous stimulation (TNS) for tinnitus. Except for 3 normal hearing patients, all had cochlear hearing losses. The authors found that tinnitus disappeared in none of the patients but diminished in 7 patients, versus a diminution of tinnitus in 3 of 24 nontreated controls.
In a study that evaluated the effects of psychological factors on the outcome of TENS for patients with chronic tinnitus (n = 27), Collet and associates (1987) found that the 15 patients (55.6%) who did not improve showed higher pre-treatment scores of depression, psychasthenia, and schizophrenia. These findings indicated that patients with psychiatric problems, such as those mentioned above, are unlikely to benefit from treatment.
According to available literature, transcutaneous electrical stimulation for tinnitus is contraindicated in persons with the following conditions:
- Persons taking medications for other diseases/conditions known to have a side effect of tinnitus, such as aspirin, Vasotec (enalapril maleate), etc.; or
- Persons with active ear disease; or
- Persons with cardiac pacemakers, implanted stapes prostheses or other implanted devices, which may be affected by electrical signals; or
- Persons with psychiatric problems such as schizophrenia, depression, hysteria, or hypochondria; or
- Women who are pregnant.
In a systematic review and meta-analysis, Byun et al. (2020) assessed the effectiveness of transcutaneous electrical nerve stimulation (TENS) for treating tinnitus. The researchers conducted a search across several databases, including PubMed, Scopus, Web of Science, and the Cochrane Library, using the terms "Transcutaneous Electric Nerve Stimulation" and "Tinnitus." They included double- or single-blinded randomized controlled trials, randomized comparison trials, prospective or retrospective observational studies, and case series, while excluding non-English studies, nonhuman studies, case reports with five or fewer cases, and review articles. Data extracted included the Tinnitus Handicap Inventory (THI), Visual Analog Scale (VAS), and perceived tinnitus suppression post-treatment, along with additional information on tinnitus laterality, symptom duration, electrode placement, follow-up time, tinnitus etiology, and treatment side effects. The literature search identified 2,941 unique articles, and after reviewing 118 full-text articles, 17 studies involving 1,215 patients were included in the final analysis. Four studies provided data for a meta-analysis of pre- and post-treatment THI and VAS scores, revealing a significant overall reduction in THI (-7.55 [-10.93 to -4.18], p < 0.0001) and VAS (-0.65 [-0.99 to -0.30], p < 0.0002). A meta-analysis of proportions from 13 studies indicated that tinnitus suppression occurred in 40.0% [28.9-51.7%] of patients, with 22.2% [12.2-29.7%] experiencing complete suppression and 10.2% [0.2-31.9%] showing persistent improvement at three months. The authors concluded that TENS is a safe and feasible treatment option for tinnitus and should be considered among the various interventions available for this condition.
Aly et al. (2025) conducted a single‑center, non‑blinded, pre–post interventional study assessing the effect of transcutaneous electrical nerve stimulation targeting the auricular branch of the vagus nerve (ta‑VNS/TENS) on subjective tinnitus in 64 normal‑hearing adults (38 males, 26 females) aged 20–60 years, including 15 participants with chronic comorbidities (diabetes mellitus, hypertension, or both). All participants reported subjective tinnitus, and tinnitus loudness was measured using a visual analogue scale (VAS) immediately before and after stimulation. The study demonstrated a statistically significant short‑term reduction in tinnitus loudness, with 45 of 64 participants (70.3%) reporting improvement and nine achieving complete tinnitus resolution; however, no statistically significant associations were identified between demographic or clinical variables and degree of response, although greater reduction was noted among those with right‑sided or whistling tinnitus. Major limitations include absence of a placebo‑controlled group, non‑blinded design, reliance on subjective self‑reported outcomes, small sample size, single‑center setting, and lack of long‑term follow‑up to assess durability of residual inhibition. While results suggest ta‑VNS may provide short‑term symptomatic relief in some patients with subjective tinnitus, the evidence remains insufficient to support widespread clinical use, and larger, multicenter randomized controlled trials with standardized objective measures and longitudinal follow‑up are required to determine medical necessity and durability of benefit.
In a systematic review and meta-analysis, Shen et al. (2026) evaluated the efficacy and safety of TENS for the treatment of subjective tinnitus in adults. The data sources included the Cochrane Library, PubMed, EMBASE, Web of Science, VIP, WanFang, CNKI, SinoMed, and ClinicalTrials.gov. The study selection focused on RCTs that compared TENS with sham or active controls for subjective tinnitus. Data were extracted and synthesized following PRISMA guidelines, with primary outcomes being the changes in Tinnitus Handicap Inventory (THI) and Visual Analog Scale (VAS) scores for loudness and annoyance. The meta-analysis included seven RCTs with a total of 342 patients. TENS demonstrated a clinically meaningful reduction in THI scores compared to controls (Mean Difference [MD] = -8.60, 95% CI: -13.39 to -3.81), although there was substantial heterogeneity (I² = 62%). TENS did not significantly impact tinnitus loudness or annoyance. A sensitivity analysis revealed that a single active-control trial contributed to the heterogeneity; after its removal, the effect of TENS versus sham control on THI was larger and more consistent (MD = -10.48, 95% CI: -13.42 to -7.54; I² = 11%). The certainty of evidence was rated as "Very Low," and no severe adverse events were reported. The authors concluded that, based on very low-certainty evidence, TENS safely provides a clinically meaningful reduction in THI but does not affect perceived loudness or annoyance, with the most significant effects observed against placebo controls. They emphasized the need for further high-quality RCTs with larger sample sizes to confirm these findings.
Extra-Cochlear Electrical Stimulation
Chen et al (2025) noted that tinnitus remains a significant challenge due to limited effective therapeutic interventions. Interestingly, patients with CI have reported significant relief from tinnitus symptoms, although the underlying mechanisms remain unclear and intra-cochlear implantation risks cochlear damage and hearing loss. These researchers reported targeted intra-cochlear ES in guinea pigs with noise-induced hearing loss (NIHL) reversed tinnitus-related maladaptive plasticity in the cochlear nucleus, characterized by reduced auditory innervation, increased somatosensory innervation, and diminished inhibitory neural networks. Furthermore, a customized extra-cochlear ES delivered by a newly designed extra-cochlear electrode array to guinea pigs with salicylate-induced tinnitus also reversed the afore-mentioned maladaptive plasticity and alleviated tinnitus without causing additional cochlear damage or hearing loss. The authors concluded that these findings suggested that CI-delivered ES may alleviate tinnitus by reversing maladaptive cochlear nucleus plasticity; this extra-cochlear ES strategy offers a promising tinnitus treatment with minimal risk to hearing.
These researchers stated that in this study, they focused on structural changes within the cochlear nucleus of NIHL guinea pigs, correlating these findings with existing data from salicylate- or noise-induced tinnitus models. This dual approach offered a promising avenue for examining how cochlear implants may mitigate tinnitus, contributing to a more comprehensive understanding of the underlying mechanisms and informing future therapeutic strategies. Due to the lack of practical methods for evaluating tinnitus behaviors in guinea pigs with severe hearing loss, further investigations are needed to examine if the vesicular glutamate transporters (VGLUT) changes observed in the cochlear nucleus of NIHL animals are directly associated with tinnitus reduction. Moreover, the development of tinnitus in humans is complex, and significant differences exist between animal models and human cases. These differences must be considered when applying these findings to clinical settings.
Eye Movement Desensitization and Reprocessing
In a prospective, interventional, single-center study, Phillips and colleagues (2019) examined the effectiveness of eye movement desensitization and reprocessing (EMDR) for the treatment of tinnitus. Subjects were provided with tEMDR, which bespoke EMDR protocol that was developed specifically to treat individuals with tinnitus. Subjects received a maximum of 10 sessions of tEMDR. Outcome measures including tinnitus questionnaires and mood questionnaires were recorded at baseline, discharge, and at 6 months post-discharge; THI and BDI scores demonstrated a statistically significant improvement at discharge after EMDR intervention (p = 0.0005 and p = 0.0098, respectively); this improvement was maintained at 6 months post-discharge. There was also a moderate but not significant (p = .0625) improvement in Beck Anxiety Inventory (BAI) scores. The authors concluded that the findings of this study has demonstrated that the provision of tEMDR has resulted in a clinically and statistically significant improvement in tinnitus symptoms in the majority of those who took part. Furthermore, the treatment effect was maintained at 6 months after treatment ceased. This study is of particular interest, as the study protocol was designed to be purposefully inclusive of a diverse range of tinnitus patients. However, as a small uncontrolled study, these results do not consider the significant effects of placebo and therapist interaction. These researchers stated that larger high-quality studies are needed for the verification of these preliminary results. Level of evidence = 4.
Luyten and associates (2019) noted that in scientific research, tinnitus is compared to phantom limb pain. Starting from tinnitus as a phantom percept , these researchers aim to show that the operating mechanisms of EMDR may also be an effective treatment method for patients with subjective tinnitus. The aim of this randomized controlled study with blind evaluator is to examine the effect of EMDR compared to CBT in chronic tinnitus patients. To the authors’ knowledge, there are no other studies that evaluate both methods simultaneously. A total of 166 patients with subjective, chronic, non-pulsatile tinnitus will be randomized in 2 treatment groups: TRT + CBT versus TRT + EMDR. The experimental group will receive the bi-modal therapy TRT/EMDR and the active control group will receive the bi-modal therapy TRT/CBT. Evaluations will take place at baseline before therapy, at the end of the treatment and 3 months after therapy. The score on the TFI will be used as the primary outcome measurement; secondary outcome measurements are the VAS of loudness, TQ, hospital anxiety and depression scale (HADS), hyperacusis questionnaire (HQ), psycho-acoustic measurements and event-related potentials (ERP). The objective is to examine if the bi-modal therapy TRT and EMDR could provide faster and/or more relief from the annoyance experienced in chronic tinnitus patients' daily lives compared to the bi-modal therapy TRT and CBT. So far there has been no prospective, randomized controlled, clinical trial with blind evaluator that compares CBT and EMDR as a treatment for tinnitus.
Intra-Cranial Venous Sinus Stenting
Boddu et al (2016) examined the role of venous sinus stenting (VSS) in the treatment of pulsatile tinnitus among patients with Idiopathic Intracranial Hypertension (IIH) and significant venous sinus stenosis. A total of 37 consecutive patients with IIH and venous sinus stenosis who were treated with VSS between January 2012 and January 2016 were prospectively evaluated. Patients without pulsatile tinnitus were excluded. Tinnitus severity was categorized based on THI at pre-stent, day-0, 1-month, 3-month, 6-month, 12-month, 18-month, and 2-year follow-up. Demographics, BMI, pre- and post-VSS trans-stenotic pressure gradient were documented. Statistical analysis was carried out using Pearson's correlation, Chi-square analysis and Fischer's exact test. A total of 29 patients with a mean age of 29.5 ± 8.5 years (male:female = 1:28) were included in this trial. Median (mean) THI pre- and post-stenting were: 4 (3.7) and 1 (1), respectively. Median time of tinnitus resolution post-VSS was 0-days. There was significant improvement of THI (Δ mean: 2.7 THI [95 % CI: 2.3 to 3.1 THI], p < 0.001) and transverse-distal sigmoid sinus gradient (Δ mean: -15.3 mm Hg [95 % CI: 12.7 to 18.0 mm Hg], p < 0.001) post-stenting. Mean follow-up duration of 26.4 ± 9.8 months (3 to 44 months); VSS was feasible in 100 % patients with no procedural complications; and 3 patients (10 %) had recurrent sinus stenosis and tinnitus at mean follow-up of 12 months (6 to 30 months). The authors concluded that VSS was a feasible, safe and effective technique for successful treatment of pulsatile tinnitus in patients with IIH and significant venous sinus stenosis. Complete resolution of the tinnitus was reported immediately after VSS in this patient cohort. Moreover, these researchers stated that larger, prospective studies with specific focus on audiometric evaluation and long-term follow-up are needed to confirm these findings. This group of investigators has initiated a prospective trial examining the safety and effectiveness of VSS in patients with pulsatile tinnitus and venous sinus stenosis.
The authors stated that this study had several drawbacks. First, there was a subjective component and possible bias when using a self-rating scale for tinnitus, although frequently reported and widely used previously, have been validated for discriminative purposes only in clinical practice. Second, otologic evaluation based on pure tone audiometry was not included in this study, which precluded the objective evaluation of hearing impairment, which is an important aspect in tinnitus patients in general. However, as the patients reported complete resolution of tinnitus post-stenting as opposed to mere improvement or partial resolution, it was reasonable to consider this change an actual effect rather than variability of the self-reported scale. Third, this study cohort included only patients with proven IIH; these findings must be applied with caution when extrapolated to non-IIH patients with pulsatile tinnitus.
In a prospective study, Patsalides et al (2021) examined the safety and effectiveness of VSS for patients with isolated pulsatile tinnitus and lateral sinus stenosis. Patients with isolated pulsatile tinnitus and lateral sinus stenosis with a minimum trans stenotic gradient of 4 mm Hg were treated with stenting. Pulsatile tinnitus before and after treatment was assessed with the THI. Peri-procedural AEs, neurological complications, as well as clinical and radiographic follow-up were also recorded. A total of 42 patients (41 females and 1 male) were included in the study (median age of 37.5 years); 30 patients had post-stenotic fusiform, and 12 had post-stenotic saccular venous sinus aneurysm. In addition to stenting, coils were used to treat the patients with saccular venous aneurysms. The median follow-up was 5 months (range of 1 to 34 months). Most patients had complete (39/42) or near-complete (2/42) resolution of their pulsatile tinnitus post-procedure. There were no serious AEs. The authors concluded that the findings of this study demonstrated that in carefully selected patients, VSS offered durable resolution of pulsatile tinnitus caused by lateral sinus stenosis. These investigators noted that proper clinical and imaging work-up was needed, as the effectiveness of this approach depended on the correct diagnosis.
The authors stated that the drawbacks of this trial included the lack of control or comparison group and the relative short-term follow-up (median of 5 months). In the 2 patients who were treated for the lateral sinus stenosis and the jugular bulb diverticulum at the same time, it was impossible to know how much each condition was contributing to the pulsatile tinnitus. Similarly, these researchers acknowledged the fact that saccular aneurysms of the venous sinuses or the jugular bulb could independently cause pulsatile tinnitus. By treating the stenosis and aneurysms at the same time, it was impossible to know how much each lesion contributed to pulsatile tinnitus, and whether treating the saccular aneurysms was in fact absolutely necessary. Lastly, as lumbar puncture was not carried out in every patient, it was possible that some patients had increased intracranial pressure.
Fiani et al (2021) noted that pulsatile tinnitus presents as a unique variation of tinnitus in which a conscious perception of the heart beat is localized to the ears in either unilateral or bilateral fashion. The sensation is typically caused by an increase in turbulent blood flow in the affected ear, in most cases, due to a structural abnormality of the venous sinuses -- the most common of which being stenosis. These investigators discussed the etiology of pulsatile tinnitus followed by indications for treatment of various pathologies that have been successfully treated with VSS and have resulted in resolution of auditory symptoms. They queried PubMed database using combinations of the keywords "venous sinus stenting", "endovascular treatment", and "pulsatile tinnitus" to identify relevant studies published in English after 2001 and before December 1, 2020 and verified selected. The findings corroborated with those published in previous reviews reporting a high rate of pulsatile tinnitus resolution with VSS. The authors concluded that the success of VSS was clinically relevant as an effective treatment option for patients suffering from pulsatile tinnitus. Moreover, these researchers stated that future applications and studies with larger cohorts of patients are needed; and are currently being developed to further demonstrate the effectiveness of VSS in the treatment of pulsatile tinnitus.
These investigators stated that although the data regarding resolution of pulsatile tinnitus via stenting is promising, there are limitations in the interpretation of available data due to smaller study cohorts. This was especially true in studies describing AVM which are typically single case studies presenting with various complications making it difficult to ascertain the effectiveness of stenting when a patient was high-risk for rupture and re-stenosis. Although the Dandy criteria are currently used for diagnosis of IIH, criteria for determining whether venous stenting is needed are not entirely clear and a consensus on such criteria has yet to be established. These researchers noted that additional studies are also needed to determine long-term resolution of pulsatile tinnitus in patients with venous sinus thrombosis as the current literature available did not present with sufficient data specifically investigating the connection between stenting in venous sinus thrombosis and pulsatile tinnitus severity (and ultimately resolution). These researchers stated that although there is currently no randomized data supporting VSS for the treatment of pulsatile tinnitus, a prospective and randomized trial is ongoing at the Weill Medical College of Cornell University (NCT02734576).
Pandey et al (2024) stated that although many case series and meta-analyses have shown the effectiveness of VSS in the treatment of IIH and IIH-associated pulsatile tinnitus, there remain numerous challenges to be resolved. There is no widespread agreement on candidacy; pressure gradient, and failed medical treatment are common indications; however, not all clinicians require medical refractoriness as a criterion. Venous manometry, venography, and cerebral angiography are essential tools for patient assessment, but again disagreements exist regarding the best, or most appropriate, diagnostic imaging choice. Challenges with the VSS technique also exist, such as stent choice and deployment. There are considerations regarding post-procedural balloon angioplasty and pharmacotherapy, but there is insufficient evidence to formalize post-operative decision-making. Although complications of VSS are relatively rare, they include in-stent stenosis, hemorrhage, and subdural hematoma, and the learning curve for VSS presents specific challenges in navigating venous anatomy, emphasizing the need for wider availability of high-quality training. Recurrence of symptoms, especially stent-adjacent stenosis, poses challenges, and although re-stenting and cerebrospinal fluid (CSF)-diverting procedures are options, there is a need for clearer criteria for re-treatment strategies. The authors concluded that despite these challenges, when comparing VSS with traditional CSF-diverting procedures, VSS emerges as a favorable option, with strong clinical outcomes, lower complication rates, and cost-effectiveness. Moreover, these researchers stated that further research is needed to refine techniques and indications and address specific aspects of VSS to overcome these challenges.
Wang et al (2024) provided an updated approach to the evaluation and management of pulsatile tinnitus, an uncommon but often treatable subtype of tinnitus. These researchers noted that secondary pulsatile tinnitus can be due to either vascular or non-vascular etiologies, including, but not limited to: neoplasm, arterio-venous malformation or fistula (AVM or AVF), IIH, dural venous sinus stenosis, oto-acoustic etiologies (e.g., oto-sclerosis, patulous eustachian tube) and bony defects (e.g., superior semicircular canal dehiscence). Computed tomography (CT) and MRI have comparable diagnostic yield, although each may be more sensitive to specific etiologies. If initial vascular imaging is negative and a vascular etiology is strongly suspected, digital subtraction angiography (DSA) may further aid in the diagnosis. Many vascular etiologies of pulsatile tinnitus can be managed endovascularly, often resulting in improvement or resolution of pulsatile tinnitus. Notably, VSS is an emerging approach for the treatment of pulsatile tinnitus secondary to IIH with venous sinus stenosis. Careful history and physical examination could aid in establishing the differential diagnosis for pulsatile tinnitus and guide subsequent evaluation and management. These investigators stated that additional studies on the effectiveness and long-term outcome of VSS for venous stenosis are needed.
Furthermore, an UpToDate review on “Treatment of tinnitus” (Dinces, 2024) does not mention venous sinus stenting as a management/therapeutic option.
Intra-Tympanic Administration of Corticosteroids
- lidocaine, although effective in decreasing tinnitus, has been largely abandoned because of its severe side-effect profile and need for inpatient administration,
- corticosteroids have been associated with few if any side effects,
- the good results reported in the literature with intra-tympanic steroids for treating tinnitus of various causes should be viewed with caution, because most are retrospective and uncontrolled studies,
- some Meniere's disease patients with tinnitus may experience tinnitus improvement following intra-tympanic steroids. This treatment may be considered in such patients, especially for those with good hearing,
- gentamicin is effective in eliminating or reducing tinnitus in a significant number of patients with Meniere's disease and may be considered especially for those with non-serviceable hearing,
- further prospective, randomized, controlled studies to evaluate the effect of intra-tympanic perfusion for the treatment of tinnitus are warranted.
In a randomized, prospective, single-blind study, Araújo and colleagues (2005) tested the effectiveness of intra-tympanic dexamethasone injections as a treatment for severe disabling cochlear tinnitus. A total of 36 patients with severe disabling tinnitus predominantly of cochlear origin were randomly assigned to receive intra-tympanic injections of a dexamethasone solution or isotonic saline solution. Under topical anesthesia and after randomization, 36 patients received 0.5 ml intra-tympanic injections once per week for 4 weeks of either a 4 mg/ml dexamethasone solution or saline solution. Five patients were excluded from analysis because they did not complete the treatment or did not return for follow-up. Main outcome measure was improvement of tinnitus measured with a VAS. The 2 groups were similar in age, sex, tinnitus laterality, measurement of tinnitus intensity on the VAS, and main otologic diagnosis. These researchers considered a 2-point improvement on the VAS to be significant. Twenty-nine percent of the ears in the saline group and 33 % of the ears in the dexamethasone group showed significant improvement immediately after completion of treatment. These measurements were not significantly different from each other. Follow-up varied from 13 to 31 months, and the patients with improved tinnitus returned to the initial measurements over time. The authors concluded that there was no advantage in intra-tympanic injections of dexamethasone over saline solution in the treatment of severe, disabling tinnitus. Both solutions produced a placebo-like improvement.
In a prospective, randomized, placebo-controlled, single-blinded study, Topak et al. (2009) examined if intra-tympanically injected methylprednisolone is effective in treating subjective tinnitus refractory to medical treatment. A total of 70 adult patients with subjective tinnitus of cochlear origin were randomly assigned to receive intra-tympanic injection of either methylprednisolone or saline solution. The treatment protocol comprised 3 intra-tympanic injections, 1 per week for 3 weeks. Improvement in tinnitus severity was measured by a self-rated tinnitus loudness scale and by the tinnitus severity index, at baseline and 2 weeks after the last injection. Data for 59 patients were available for analysis. There was no significant difference between the 2 treatment groups regarding age, sex, pure tone average, pre-treatment tinnitus intensity, tinnitus laterality, or tinnitus duration. There was a significant post-treatment improvement in self-rated tinnitus loudness scale results in both groups. No significant post-treatment changes in the tinnitus severity index individual and total scores were observed in either group. The most frequently encountered side effects were pain during injection, vertigo, a burning sensation around the ear and in the throat, and a bitter taste. A burning sensation and bitter taste were observed more often in the methylprednisolone group compared with the placebo group. The authors concluded that these findings indicated that intra-tympanic methylprednisolone has no benefit compared with placebo for the treatment of subjective tinnitus of cochlear origin refractory to medical treatment.
In a Cochrane review, Phillips and Westerberg (2011) assessed the effectiveness of intra-tympanic steroids on the frequency and severity of attacks of vertigo, on chronic symptoms such as tinnitus, imbalance, and hearing loss, and on the progression of these symptoms in patients with definite Meniere's disease or syndrome, as defined by the AAO-HNS Committee. These investigators searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; ICTRP; and additional sources for published and unpublished trials. The date of the most recent search was January 13, 2011. Randomized controlled trials of intra-tympanic dexamethasone versus placebo in patients with Meniere's disease were selected for this analysis. Two authors independently assessed trial risk of bias and extracted data. They contacted study authors for further information where possible. A single trial containing 22 patients, with a low risk of bias, was included. This trial found that after 24 months, compared with placebo, the use of intra-tympanic dexamethasone demonstrated a statistically significant improvement in vertigo as defined by a respective improvement in functional level (90% versus 42%), class (82% versus 57%), change in Dizziness Handicap Inventory scores (60.4 versus 41.3), and mean vertigo subjective improvement (90% versus 57%). The treatment regime described by the authors involved daily injections of dexamethasone solution 4 mg/ml for 5 consecutive days. These results were clinically significant. No complications were reported. The authors concluded that these findings of a single trial provide limited evidence to support the effectiveness of intra-tympanic steroids in patients with Meniere's disease. This trial demonstrated a statistically and clinically significant improvement in the frequency and severity of vertigo measured 24 months after the treatment was administered. It is important to note that there were a few aspects of the study that the authors were unable to clarify with the study authors.
The American Academy of Otolaryngology - Head and Neck Surgery Foundation’s clinical practice guideline on "Tinnitus" (2014) stated that clinicians should not routinely recommend intra-tympanic medications for a primary indication of treating persistent, bothersome tinnitus.
In a prospective, randomized, placebo-controlled, double-blinded, multi-center study, Lee and colleagues (2018) examined the effectiveness of intra-tympanic dexamethasone injection (ITDI) in acute tinnitus of presumed cochlear origin. Between August 2013 and December 2015, a total of 54 patients with unilateral tinnitus were enrolled at 4 different centers. Patients were assigned either to an ITDI (n = 27) or an intra-tympanic normal saline injection (ITNI; n = 27) group through block randomization. Intra-tympanic injections were administered 4 times over 2 weeks. At 4 weeks after the initial injection, these researchers analyzed the improvement rates of tinnitus using the THI and VAS for loudness, awareness, and annoyance. They defined improvement as the reduction of more than 7 points or of more than 20% in the final THI score compared to the initial THI score. The initial mean hearing thresholds and VAS and THI scores of the 2 groups did not differ significantly. At 4 weeks after the initial injection, the mean VAS and THI scores of both groups had significantly reduced. However, the improvement rate did not differ significantly between the groups (ITDI, 51.9%; ITNI, 59.3%). The authors concluded that these findings indicated that ITDI might not be more effective than ITNI for the treatment of acute unilateral tinnitus; thus, ITDI should not be considered the main treatment for patients presenting with acute tinnitus as the primary symptom.
Sayoo and Kumar (2019) noted that different methods had been developed for managing tinnitus, but none has offered a permanent cure. In this trial, these researchers employed a simple procedure of intra-tympanic injection of dexamethasone in managing tinnitus patients. A total of 40 subjects (26 females and 14 males aged 15 to 65 years) were included in this study; 22 of them complained of tinnitus only, and the remaining 18 complained of tinnitus with impaired hearing that was confirmed further by pure-tone audiometry. Dexamethasone injection was administered under otologic microscopic guidance via the postero-inferior quadrant of the tympanic membrane at weekly intervals. After receiving several injections, 24 patients (60%) reported complete disappearance of tinnitus, 10 (25%) still had residual tinnitus but comparatively less severe, and 6 (15%) reported no improvement. This was a small, uncontrolled study; its findings need to be validated by well-designed studies.
Chung and colleagues (2022) stated that ITDI has been introduced as a therapeutic option for subjective tinnitus; however, the effects of ITDI on patients with tinnitus remain unclear. In a systematic review and meta-analysis, these researchers examined the effectiveness of ITDI for tinnitus treatment. They searched Medline, the Cochrane Central Register of Controlled Trials, and Embase. A total of 4 double-blind RCTs that examined the effectiveness of ITDI compared with a placebo were deemed eligible for a quantitative meta-analysis, while 4 prospective studies and 7 retrospective studies reporting the effectiveness of ITDI on tinnitus treatment were included in a qualitative synthesis. In the 4 studies included in the quantitative meta-analysis, ITDI did not show evidence of tinnitus improvement compared with placebo (odds ratio [OR], 1.38; 95% CI: 0.53 to 3.61). In the 11 studies included in the qualitative synthesis, 7 retrospective studies without controls reported rates of tinnitus improvement after ITDI ranging from 35.9% to 91.3%. In the 4 prospective studies with controls, ITDI appeared to be effective when combined with other drugs for tinnitus treatment. The authors concluded that ITDI alone did not show a significant effect for treating tinnitus compared with placebo; however, the potential of combination treatment of ITDI with other drugs for tinnitus therapy should be further studied in more systematic research.
Lenire Device (Bi-Modal Neuromodulation)
In an open-label, pilot study, Hamilton et al (2016) examined the safety and feasibility of a device that delivers simultaneous auditory and somatosensory stimulation (bi-modal stimulation ) for the treatment of the symptoms of chronic tinnitus. A cohort of 54 patients used the stimulation device for 10 weeks. Auditory stimulation was delivered via headphones and somatosensory stimulation was delivered via electrical stimulation of the tongue. Patient usage, logged by the device, was used to classify patients as compliant or non-compliant. Safety was assessed by reported adverse events (AEs) and changes in tinnitus outcome measures. Response to treatment was evaluated using tinnitus outcome measures: minimum masking level (MML), tinnitus loudness matching (TLM), and THI. The device was well-tolerated by patients and no AEs or serious difficulties using the device were reported. Overall, 68 % of patients met the defined compliance threshold. Compliant patients (n = 30) showed statistically significant improvements in mean outcome measures after 10 weeks of treatment: THI (-11.7 points, p < 0.001), TLM (-7.5 dB, p < 0.001), and MML (-9.7 dB, p < 0.001). The non-compliant group (n = 14) showed no statistical improvements. The authors concluded that the findings of this study showed the safety and feasibility of a new bi-modal stimulation device and supported the potential effectiveness of this new treatment for tinnitus. These researchers stated that the results of this study supported the continued evaluation of this intervention as a treatment for tinnitus. The next step is a series of clinical trials to disassociate the specific and unspecific effects of this therapeutic intervention. Parameter optimization studies will examine the association of the bi‐modal stimuli to determine the optimal stimulation settings. These studies will be followed by a Randomised Control Trial to compare this intervention to a sham treatment. Finally, follow‐up assessments will be included in all subsequent studies to examine the permanency of the effect observed in treatment groups.
D'Arcy et al (2017) presented the study protocol for an exploratory trial to optimize stimulation parameters and patient subtyping on bi-modal stimulation in the treatment of tinnitus. This is a 2-site, randomised, triple-blind, exploratory study of a proprietary neuromodulation device with a pre-post and 12-month follow-up design. A total of 3 different bi-modal stimulation parameter sets will be examined. The study will enroll 342 patients, split 80:20 between 2 sites (Dublin, Ireland and Regensburg, Germany), to complete 12 weeks of treatment with the device. Patients will be allocated to 1 of 3 arms using a step-wise stratification according to 4 binary categories: tinnitus tonality, sound level tolerance (using loudness discomfort level of less than 60 dB SL as an indicator for hyperacusis), hearing thresholds and presence of a noise-induced audiometric profile. The main indicators of relative clinical efficacy for the 3 different parameter sets are 2 patient-reported outcomes measures (PROMs), the THI and the TFI, after 12 weeks of intervention. Clinical effectiveness will be further examined in a series of patient subtypes, split by the stratification variables and by presence of a somatic tinnitus. Evidence for sustained effects on the psychological and functional impact of tinnitus will be followed up for 12 months. Safety data will be collected and reported. A number of feasibility measures to inform future trial design include the following: reasons for exclusion, completeness of data collection, attrition rates, patient's adherence to the device usage as per manufacturer's instructions and evaluation of alternative methods for estimating tinnitus impact and tinnitus loudness. (It should be noted that this work was supported by Neuromod Devices Ltd).
Conlon et al (2019) noted that there is increasing evidence from animal and human studies that bi-modal neuromodulation combining sound and electrical somatosensory stimulation of the tongue could induce extensive brain changes and treat tinnitus. These researchers stated that the principal goals of the proposed clinical study are to confirm the safety, tolerability, and effectiveness of treatment showed in a previous large-scale study of bi-modal auditory and trigeminal nerve (tongue) stimulation (Treatment Evaluation of Neuromodulation for Tinnitus - Stage A1); examine the therapeutic effects of adjusting stimulation parameters over time; and determine the contribution of different features of bi-modal stimulation in improving tinnitus outcomes. This study will be a prospective, randomized, double-blind, parallel-arm, comparative clinical trial of a 12-week treatment for tinnitus using a Conformité Européenne (CE)-marked device with a pre-post and 12-month follow-up design. A total of 4 treatment arms will be examined, in which each arm consists of 2 different stimulation settings, with the 1st setting presented during the first 6 weeks and the 2nd setting presented during the next 6 weeks of treatment. The study will enroll 192 participants, split in a ratio of 80:80:16:16 across the 4 arms. Subjects will be randomized to 1 of 4 arms and stratified to minimize baseline variability in 4 categories: 2 separate strata for sound level tolerance (using loudness discomfort level as indicators for hyperacusis severity), high tinnitus symptom severity based on the THI, and tinnitus laterality. The primary effectiveness endpoints are within-arm changes in THI and TFI as well as between-arm changes in THI after 6 weeks of treatment for the full cohort and 2 subgroups of tinnitus participants (i.e., 1 hyperacusis subgroup and a high tinnitus symptom severity subgroup). Additional effectiveness endpoints include within-arm or between-arm changes in THI after 6 or 12 weeks of treatment and in different subgroups of tinnitus subjects as well as at post-treatment assessments at 6 weeks, 6 months, and 12 months. Treatment safety, attrition rates, and compliance rates will also be assessed and reported. This study protocol was approved by the Tallaght University Hospital/St. James's Hospital Joint Research Ethics Committee in Dublin, Ireland. The 1st participant was enrolled on March 20, 2018. The data collection and database lock are expected to be completed by February 2020, and the data analysis and manuscript submission are expected to be conducted in the fall of 2020. The authors stated that the findings of this study will be disseminated to relevant research, clinical, and health services and patient communities via publications in peer-reviewed journals, and presentations at scientific and clinical conferences.
These investigators stated that a limitation of the study design is that the effectiveness due to stimulation settings used during the second 6 weeks of treatment may not be directly comparable with effectiveness due to the stimulation settings in the first 6 weeks of treatment because of possible carry-over effects. The cumulative effects from both stimulation settings used in each treatment arm can still be compared between arms to achieve one of the main objectives of the study. (It should be noted that several authors (BC, CH, SH, EM, and HHL) have financial interest and/or are employed by Neuromod Devices Limited. Also, several authors (DAH, SV, and BL) serve on the Scientific Advisory Board of Neuromod Devices Limited and receive financial compensation for their services to the company).
Conlon et al (2020) stated that tinnitus is a phantom auditory perception coded in the brain that can be bothersome or debilitating, affecting 10 % to 15 % of the population. Currently, there is no clinically recommended drug or device treatment for this major health condition. Animal research has revealed that sound paired with electrical somatosensory stimulation could drive extensive plasticity within the brain for tinnitus treatment. To examine this bi-modal neuromodulation approach in humans, these investigators evaluated a non-invasive device that delivers sound to the ears and electrical stimulation to the tongue in a randomized, double-blinded, exploratory study that enrolled 326 adults with chronic subjective tinnitus. Subjects were randomized into 3 parallel arms with different stimulation settings. Clinical outcomes were evaluated over a 12-week treatment period and a 12-month post-treatment phase. For the primary endpoints, subjects achieved a statistically significant reduction in tinnitus symptom severity at the end of treatment based on 2 commonly used outcome measures, THI (Cohen's d effect size: -0.87 to -0.92 across arms; p < 0.001) and TFI (-0.77 to -0.87; p < 0.001). Therapeutic improvements continued for 12 months after treatment for specific bi-modal stimulation settings, which had not previously been observed in a large cohort for a tinnitus intervention. The treatment also achieved high compliance and satisfaction rates with no treatment-related serious AEs. The authors concluded that these positive therapeutic and long-term results motivated further clinical trials toward establishing bi-modal neuromodulation as a clinically recommended device for the treatment of tinnitus.
The authors stated that one drawback of this trial was that all 3 arms consisted of bi-modal neuromodulation with supra-threshold intensities of sound and tongue stimulation that were required to maintain blinding, and they showed similar improvements in THI and TFI scores at the end of treatment. On the basis of the concept of paired plasticity, a significant difference would have been expected between the synchronized arm 1 and less synchronized arm 3. Although this between-arm endpoint was not achieved at the end of treatment, differences in THI and TFI scores emerged between arms during the post-treatment phase, suggesting that different stimulation settings could lead to different long-term therapeutic outcomes. Prolonged residual effects lasting 12 months would also not be expected for placebo effects. The bi-modal stimulation paradigm used by Marks et al (2018) resulted in a significant improvement in tinnitus symptoms that returned back to baseline within 3 weeks. This intervention was believed to be a legitimate treatment by the tinnitus participants, showing that simply informing subjects that they are receiving an effective bi-modal treatment did not result in a 12-month residual effect. As described above, there appeared to be a minimum duration of bi-modal neuromodulation (greater than 14 to 36 hours) needed to achieve long-term effects, which could be further sustained by using shorter delays between sound and tongue stimulation (less than 50 to 550 ms); thus, future clinical studies can be designed to show differences in long-term outcomes between treatment arms that diverge toward opposite extremes of those 2 parameter dimensions. (Several authors [B.C., C.H., S.H., E.M., C.O.C., S.L.L., S.D., and H.H.L] are/were employees, consultants, and/or shareholders of Neuromod Devices; and several authors [B.L., S.V., and D.A.H.] serve on the clinical advisory board of Neuromod Devices and receive monetary compensation for their contribution).
De Ridder et al (2021) stated that the pathophysiological mechanisms that underlie the generation and maintenance of tinnitus are being unraveled progressively. Based on this knowledge, a large variety of different neuro-modulatory interventions have been developed and are still being designed, adapting to the progressive mechanistic insights in the pathophysiology of tinnitus. rTMS targeting the temporal, temporo-parietal, and the frontal cortex has been the mainstay of non-invasive neuromodulation. Yet, the evidence is still unclear; thus, systematic meta-analyses are needed for drawing conclusions on the effectiveness of rTMS in chronic tinnitus. Different forms of transcranial electrical stimulation (tDCS, tACS, tRNS), applied over the frontal and temporal cortex, have been examined in tinnitus patients, also without robust evidence for universal efficacy. Cortex stimulation and DBS with implanted electrodes have shown benefit, yet there is insufficient evidence to support their routine clinical use. Recently, bi-modal stimulation approaches have revealed promising results and it appeared that targeting different sensory modalities in temporally combined manners may be more promising than single target approaches. The authors concluded that while most neuro-modulatory approaches appeared promising, further research is needed to aid in translating the scientific outcomes into routine clinical practice.
Conlon et al (2022) noted that more than 10 % of the population suffers from tinnitus. A new neuromodulation approach for the treatment of tinnitus has emerged that combines sound with electrical stimulation of somatosensory pathways, supported by multiple animal studies showing that bi-modal stimulation could elicit extensive neural plasticity within the auditory brain. More recently, in a large-scale clinical trial, bi-modal neuromodulation combining sound and tongue stimulation produced significant reductions in tinnitus symptom severity during the first 6 weeks of treatment, followed by diminishing improvements during the second 6 weeks of treatment. The primary objective of the large-scale randomized and double-blinded study presented in this paper was to determine if background wide-band noise as used in the previous clinical trial was necessary for bi-modal treatment effectiveness. An additional objective was to determine if adjusting the parameter settings after 6 weeks of treatment could overcome treatment habituation effects observed in the previous study. The primary endpoint at 6-weeks entailed within-arm, as well as between-arm comparisons for 2 treatment arms with different bi-modal neuromodulation settings based on two widely used and validated outcome instruments, THI and TFI. Both treatment arms exhibited a statistically significant reduction in tinnitus symptoms during the first 6-weeks, which was further reduced significantly during the second 6-weeks by changing the parameter settings (Cohen's d effect size for full treatment period per arm and outcome measure ranged from - 0.7 to - 1.4). There were no significant differences between arms, in which tongue stimulation combined with only pure tones and without background wide-band noise was sufficient to reduce tinnitus symptoms. These therapeutic effects were sustained up to 12 months after the treatment ended. The study included 2 additional exploratory arms, including 1 arm that presented only sound stimuli during the first 6 weeks of treatment and bi-modal stimulation in the second 6 weeks of treatment. This arm showed the criticality of combining tongue stimulation with sound for treatment effectiveness. Overall, there were no treatment-related serious AEs and a high compliance rate (83.8 %) with 70.3 % of subjects indicating benefit. The authors concluded that the discovery that adjusting stimulation parameters overcame previously observed treatment habituation could be used to attain greater therapeutic effects and opens up new opportunities for optimizing stimuli and enhancing clinical outcomes for tinnitus patients with bi-modal neuromodulation. (The study was sponsored by Neuromod Devices Limited).
Furthermore, an UpToDate review on “Treatment of tinnitus” (Dinces, 2024) does not mention the Lenire device/bi-modal neuromodulation as a management option.
Lidocaine
Kallio et al. (2008) stated that intravenous (IV) lidocaine has been used to ameliorate tinnitus, but in general, its effect has been limited. The longer-acting local anesthetic ropivacaine may be more effective. These investigators compared ropivacaine with lidocaine for the treatment of tinnitus. A total of 19 patients suffering from chronic tinnitus participated in a randomized, double-blind, cross-over study, receiving a 30-minute IV infusion of ropivacaine or lidocaine at a dose of 1.5 mg/kg at an interval of 2 to 3 months. The intensity of tinnitus was evaluated on the Tinnitus Handicap Inventory (THI) scale and on the Visual Analog Scale (VAS). Plasma ropivacaine and lidocaine concentrations were determined. In both treatments, the infusion significantly decreased the VAS score. At the end of the infusion, a greater than or equal to 50% reduction in VAS score was observed in 5 patients after ropivacaine and in 1 patient after lidocaine; however, this effect was sustained for only 1 hour in 3 patients. The THI scores did not differ significantly within or between treatments. On the post-infusion day, 3 patients after ropivacaine and 5 after lidocaine treatment had a greater than or equal to 30% improvement in the THI score. Four weeks later, 1 patient after ropivacaine and 2 after lidocaine had a greater than or equal to 30% reduction in the THI score. One patient developed seizures soon after ropivacaine infusion, from which he recovered uneventfully. His plasma concentration of ropivacaine was 1,817 ng/ml. The highest individual ropivacaine and lidocaine concentrations were 3,483 ng/ml and 1,680 ng/ml, respectively. The authors concluded that temporary clinically significant alleviation of tinnitus was observed only in a few individuals after both IV ropivacaine and lidocaine.
Hahn et al. (2008) performed a retrospective study of patients suffering from chronic unilateral or bilateral tinnitus that had previously been ineffectively treated by oral drugs (betahistine [Betaserc], extract of Ginkgo biloba [EGb 761], tanakan [Tebokan], and cinnarizine-dimenhydrinate [Arlevert], singly or in combination). These researchers divided 150 tinnitus patients (80 men, 70 women) into 7 treatment groups. Treatments consisted of the application of intravenous pentoxifylline, lidocaine, or vinpocetine (Cavinton) and combinations of these agents with physiotherapy and soft laser. The mean duration (± standard deviation) of tinnitus in these patients was 7.4 ± 6.0 years, and their mean age was 55.6 ± 12.5 years. The aim of the study was to compare treatment modalities and define their effectiveness for tinnitus relief. The most effective treatment was defined as a combination of Cavinton and physiotherapy. The authors found that pure lidocaine infusion therapy was ineffective. None of the treatment modalities had an objective correlate of improvement, though improvement was reported by a VAS.
The American Academy of Otolaryngology - Head and Neck Surgery Foundation’s clinical practice guideline on "Tinnitus" (2014) stated that clinicians should not routinely recommend intra-tympanic medications for a primary indication of treating persistent, bothersome tinnitus.
Lidocaine Iontophoresis
Bulow et al (2023) noted that tinnitus is a common symptom with multiple causes and therapeutic options; previous studies have examined the effect of lidocaine iontophoresis. In a systematic review, these investigators examined the effects of lidocaine iontophoresis on tinnitus. They carried out the search and analysis according to the PRISMA statement. An abstract in German or English and a performed intervention with lidocaine iontophoresis for the treatment of tinnitus, independent of the study design, were considered as inclusion criteria. Due to the heterogeneity of the studies, only a narrative synthesis was carried out. The search yielded 179 studies of which 170 were excluded. A total of 6 full-texts and 3 abstracts were included; 957 patients were treated with lidocaine iontophoresis. The % improvement in symptoms following lidocaine iontophoresis ranged from 4 % to 62 %. The qualitative assessment of the studies resulted in an overall "weak" rating for all of them. The authors concluded that due to the heterogeneity and the limited quality of the studies found, no clear statement could be made regarding the effectiveness of lidocaine iontophoresis for the treatment of tinnitus. The number of patients who benefited from therapy varied widely. Furthermore, it could not be ruled out that the effect was merely due to electrical stimulation of the cochlea. These researchers stated that further high-quality studies are needed to clarify the evidence and confirm the clinical relevance. In this context, double-blinding and placebo control should be considered in the study design. Collaboration with other professions such as pharmacologists and biochemists could aid in improving the basic understanding of this form of therapy.
The authors noted that the lack of some full texts significantly limited the synthesis and conclusion, as inadequate information was available on the interventions implemented. Due to the heterogeneity in the study design of the included studies, it was not possible to conduct a meta-analysis. In addition, the existing weak quality of the intervention studies limited the informative value of this systematic review.
Low-Level Laser Therapy / Photobiomodulation
Montazeri and colleagues (2017) determined alterations in auditory physiological and electrophysiological responses associated with temporary suppression of tinnitus induced by low-level laser therapy (LLLT). A total of 20 subjects with subjective tinnitus were included in this trial; visual analog scale (VAS) for loudness, loudness matching of tinnitus (LMT), pitch matching of tinnitus (PMT), Persian-tinnitus questionnaire (P-TQ), and Persian-tinnitus handicap inventory (P-THI) were conducted pre- and post-LLLT for all the subjects. Electrocochleography (ECochG) and distortion product otoacoustic emissions (DPOAEs) were recorded in 11 subjects. Continuous wave diode lasers, including red (630 nm) and infrared (808 nm), were applied, both designed by the Canadian Optic and Laser (COL) Center. A total of 12 sessions of LLLT were performed, with 2 sessions per week for each subject. The total dose was 120 Joules per ear per session. LLLT caused a significant decrease in subjective test scores, consisting of VAS for loudness, PMT, P-TQ, and P-THI, but did not result in a significant improvement of objective evaluating parameters except for compound action potential (CAP) amplitude. The authors concluded that the therapeutic effects of LLLT on tinnitus are still under investigation. Based on these findings, it appeared that their laser protocol might not be objectively qualified, and defining a new protocol for optimizing LLLT parameters may be an option. It was suggested that the study be repeated with tinnitus subjects who have cochlear damage as shown by otoacoustic emissions. Additionally, using the input-output function of DPOAE may be a better choice than DPOAE thresholds to investigate the effects of LLLT on the cochlea. Conducting a randomized clinical trial using animal models with larger groups of subjects over a longer time period may better reveal the effects.
In a systematic review, Ferreira and associates (2021) examined the effects of LLLT on the severity of tinnitus when compared to no therapy or other modalities of therapy. These researchers registered a systematic review protocol at the International Prospective Register of Systematic Reviews (PROSPERO) under the Registration Number CRD42019119376. They carried out a search in each of the following databases: Embase, LILACS, PubMed, Science Direct, Scopus, Web of Science, Google Scholar, and ProQuest. The inclusion criteria consisted of studies in adults over 16 years of age, randomized clinical trials in which subjects presented chronic (greater than or equal to 6 months) and subjective tinnitus (unilateral or bilateral), as well as with or without bilateral sensorineural hearing loss (SNHL), and studies that used only LLLT for the treatment of tinnitus compared to a no-therapy group or other modalities of therapy. No language or time restrictions were stipulated. The references were managed by Endnote Web and Rayyan QCRI. After the screening process, a total of 7 studies remained that met the eligibility criteria. Regarding the risk of bias, only 1 study was categorized as low-risk of bias; the remaining 6 studies were classified as moderate-risk of bias. The 7 included studies mainly examined the effects of LLLT on tinnitus using VAS, THI, pitch and loudness matching, minimum masking level, and pure-tone audiometry. All 7 selected studies found different degrees of significant results regarding tinnitus severity; however, there was no consensus among the results. The authors concluded that although LLLT showed positive effects on tinnitus severity in some studies, it was not yet possible to make any recommendations regarding its use for the treatment of tinnitus severity.
Talluri and colleagues (2022) stated that there is controversy regarding the effectiveness of photobiomodulation (PBM; also known as low-level laser therapy) in the management of tinnitus. These researchers systematically reviewed randomized controlled trials (RCTs) that examined the effectiveness of PBM in the management of tinnitus. The focused question was, "Is PBM effective in the management of tinnitus?" Indexed databases were searched up to and including June 2020 using different combinations of the following keywords: laser; diode; low-level laser therapy; photobiomodulation; tinnitus; medium-level laser; photo-biomodulation; and low-power laser; and RCTs performed on humans were included. Letters to the editor, case reports/series, commentaries, experimental studies, and historical reviews were excluded. The risk of bias was assessed using the modified Cochrane collaboration tool. The format of the current systematic review was personalized to summarize the appropriate information. A total of 10 RCTs (2 single-blinded and 8 double-blinded) were included; 1 study reported 30% and 100% resolution of tinnitus using diode and neodymium-doped yttrium aluminum garnet lasers, respectively. One study reported that PBM was effective in relieving tinnitus for up to 3 months; 8 studies reported that PBM was ineffective in the management of chronic tinnitus. The risk of bias was high in 4 studies, medium in 5 studies, and low in 1 study. The authors concluded that the effectiveness of PBM in the management of tinnitus remains debatable; these researchers stated that further power-adjusted and well-designed RCTs with long-term follow-up are needed.
Lysis of Middle Ear Tendons
Dang and Liu (2019) described a case of bilateral middle ear myoclonus (MEM) that was treated with trans-palatal Botox injection after failing surgery to section the tensor tympani and stapedial tendons. MEM is a rare disorder resulting from rhythmic contraction of middle ear muscles. An 8-year old girl presented with audible clicking tinnitus, and resultant inability to focus on school. Her parents declined medical therapy, and she underwent surgeries for tendon lysis, with only temporary relief. She had successful response to trans-palatal Botox injection to the tensor veli palatini aponeurosis. The authors concluded that trans-palatal Botox injection was a safe and reasonable alternative for treatment of MEM.
Furthermore, an UpToDate review on “Treatment of tinnitus” (Dinces, 2024) does not mention lysis of middle ear tendons as a management option.
Masking Instruments
Tinnitus masking instruments, such as maskers, hearing aids, and tinnitus devices (a combination of hearing aid and tinnitus masker), have been used to alleviate symptoms associated with tinnitus. However, the effectiveness of these instruments for treating tinnitus has not been established. These devices are all worn behind or in either the same or opposite ear affected by tinnitus. Tinnitus maskers generate a grossly broad-band high-energy noise, which most patients find to be an excessive noise intrusion that is unacceptable and intolerable.
The goal of hearing aids is to bring in more sounds from the person’s surroundings, thus naturally covering the tinnitus and making it less noticeable. Some hearing aids may exist as a combination hearing aid and a broadband noise generator or masking device for tinnitus relief. An example of a combination hearing aid includes, but is not limited to, the Phonak hearing aid combined with the Phonak tinnitus balance.
Masking devices are similar in appearance to hearing aids; however, they do not amplify sounds but instead produce constant low-level white noise intended to provide a distraction from the internal tinnitus. Masking may also be accomplished by using or enhancing background noise with tabletop sound machines, etc. Examples of masking devices include, but are not limited to, the following: Levo tinnitus symptoms masking systems; Neuromonics tinnitus treatment; Phonak tinnitus balance; Refuge tinnitus masker; Serenade tinnitus treatment; The Inhibitor; The Jump C TRT; and Unitron tinnitus masker.
A review of 69 randomized clinical trials of therapies for tinnitus (Dobie, 1999) concluded that no treatment (pharmacotherapy, psychotherapy, and various non-drug treatments, including masking) could yet be considered established in terms of providing reproducible long-term benefits in excess of placebo effects.
A systematic review of the evidence for tinnitus treatments by BMJ Clinical Evidence concluded that tinnitus masking devices and hearing aids are of "unknown effectiveness" (Savage et al., 2011).
The Centers for Medicare and Medicaid Services (CMS, 2006) has concluded: "Tinnitus masking is considered an experimental therapy at this time because of a lack of controlled clinical trials demonstrating effectiveness and the unstudied possibility of serious toxicity in the form of noise-induced hearing loss."
In a Cochrane review, Hobson et al. (2010) examined the effects of sound therapy (masking) in the management of tinnitus in adults. Prospective, randomized controlled trials recruiting adults with persistent, distressing, subjective tinnitus of any etiology, in which the management strategy included maskers, noise-generating devices, and/or hearing aids, used either as the sole management tool or in combination with other strategies, including counseling, were included in this review. A total of 6 trials (553 subjects) were included in this review. The studies varied in design, with significant heterogeneity in the evaluation of subjective tinnitus perception, using different scores, scales, tests, and questionnaires, as well as variance in the outcome measures used to assess the improvement in tinnitus sensation and quality of life. This precluded meta-analysis of the data. There was no long-term follow-up. The researchers assessed the risk of bias as medium in 3 studies and high in 3 studies. No side effects or significant morbidity were reported from the use of sound-creating devices. The authors concluded that the limited data from the included studies failed to show strong evidence of the efficacy of sound therapy in tinnitus management. The absence of conclusive evidence should not be interpreted as evidence of a lack of effectiveness. The lack of quality research in this area, in addition to the common use of combined approaches (hearing therapy plus counseling) in the management of tinnitus, is, in part, responsible for the lack of conclusive evidence.
Mexiletine
In a pilot study, Berninger et al. (2006) examined the effect of intravenously administered mexiletine on subjective tinnitus and hearing in 6 patients, who initially responded positively to lidocaine. Distinct mexiletine-induced decreases in tinnitus loudness were demonstrated in 3 subjects, as reflected by maximum VAS level reduction of 34%, 95%, and 100%, respectively. One subject reported change in tinnitus pitch, another one showed a slight (18% on VAS) tinnitus reduction, and 1 subject disclosed no effect. Side effects were seen only during 1 of 7 infusions. Mexiletine induced shifts in pure-tone threshold, transient evoked oto-acoustic emission, and acoustic reflex threshold, probably reflecting a reversible interference in the function of organ of Corti. The concentration effect relationship remained unclear and no general "therapeutic" level could be identified. The authors concluded that this study confirmed the effect of mexiletine on the auditory function and its potential as a possible therapeutic agent or a model for further development in tinnitus pharmacotherapy.
Microvascular Decompression of the Cochlea-Vestibular Nerve
- tinnitus,
- vertigo, and
- tinnitus combined with vertigo.
For the meta-analysis, IPD were collected from the papers and/or from the authors; IPD were analyzed with logistic regression analysis while accounting for study clustering. A total of 35 studies (572 patients) were included. The level of evidence provided by these studies was low. In 28% of patients with tinnitus and 32% of patients with vertigo, complete relief following MVD was reported. Patients with both tinnitus and vertigo had complete relief in 62% of cases. In 11% of patients, greater than or equal to 1 complications were reported. Meta-analysis of IPD (165 patients) demonstrated that patients with both tinnitus and vertigo had a higher chance of success (odd ratio [OR] 3.8, 95% CI: 1.45 to 10.10) than patients with tinnitus alone. No other variables were significantly related to success. The authors concluded that due to low success rates, MVD cannot be considered as a standard treatment method for tinnitus or vertigo. Moreover, a substantial complication rate was found. However, patients with combined symptoms had a higher chance of success. When combined symptoms occur, it is more likely that an NVC is the underlying pathology and MVD might be appropriate. Due to the low level of evidence in the included studies, this conclusion must be taken with caution. They stated that further validation is needed to examine if patients with combined symptoms are indeed better candidates for MVD.
Nash and colleagues (2017) examined the outcomes in cases of MVD of cranial nerve (CN) VIII for tinnitus through a critical review of the literature. A total of 43 English-language articles were gathered from PubMed and analyzed. In this review, 2 different case types were distinguished. First, tinnitus-only symptomatology, which was defined as a patient with tinnitus with or without sensorineural hearing loss. Second, mixed symptomatology, which was defined as tinnitus with symptoms of other CN dysfunction. This review reported outcomes of those with tinnitus-only symptoms. A total of 43 tinnitus-only cases were found in the literature with a 60% positive outcome rate following MVD. Analysis revealed a 5-year cut-off of pre-operative symptom duration before which a good outcome can be predicted with 78.6% sensitivity, and after which a poor outcome can be predicted with 80% specificity. The authors concluded that as the 60% success rate is more promising than several other therapeutic options open to the chronic tinnitus sufferer, future research into this field is needed.
Miscellaneous Interventions
Zenner and associates (2015) stated that chronic idiopathic tinnitus (CIT) is the most frequent type of tinnitus. A considerable number of treatment strategies are used to treat CIT; however, there is no evidence of effectiveness for many of these interventions. In order to enable scientific evidence-based treatment of CIT, German inter-disciplinary S3 guidelines have recently been constructed for the first time. These investigators presented a short form of these S3 guidelines. The guidelines were constructed based on a meta-analysis of the treatment of chronic tinnitus performed by the authors. Additionally, a systematic literature search was performed in the PubMed and Cochrane Library databases. Furthermore, a systematic search for international guidelines was performed in Google, as well as in the Guidelines International Network and National Guideline Clearinghouse (USA) database. Evidence was classified according to the Oxford Centre for Evidence-Based Medicine system. According to the guidelines, alongside counselling, manualized structured tinnitus-specific cognitive behavioral therapy (tCBT) with a validated treatment manual is available as evidence-based therapy. In addition, the guidelines recommended concurrent treatment of co-morbidities, including drug-based treatment, where appropriate. Particularly important is treatment of anxiety and depression. Where a psychic or psychiatric co-morbidity is suspected, further diagnosis and treatment should be performed by an appropriately qualified specialist (psychiatrist, neurologist, psychosomatic medicine consultant) or psychological psychotherapist. In cases accompanied by deafness or hearing loss bordering on deafness, cochlear implants may be indicated. The authors concluded that no recommendations can be made for drug-based treatment of CIT, audiotherapy, transcranial magnetic or electrical stimulation, specific forms of acoustic stimulation or music therapy; or such recommendations must remain open due to the lack of available evidence. Moreover, they stated that poly-pragmatic tinnitus treatment with therapeutic strategies for which there is no evidence of effectiveness from controlled studies is to be refused.
Zenner and colleagues (2017) stated that for auditory therapeutic measures, transcranial magnetic or direct current stimulation and specific forms of acoustic stimulation (e.g., noiser/masker, retraining therapy, music, and coordinated reset) for the treatment of chronic tinnitus the currently available evidence is not yet sufficient for supporting their recommendation.
Moreira et al. (2026) conducted a systematic review and meta-analysis to assess the effectiveness of music therapy (MT) in treating tinnitus. The aim was to gather evidence from the literature regarding the application of MT, the techniques utilized, and the outcomes achieved. The review involved a comprehensive search of articles in databases such as PubMed, Scopus, Web of Science, MEDLINE, LILACS, and SciELO up to January 2024, including studies published in English, Portuguese, and German, while excluding duplicates, literature reviews, case reports, letters, and editorials. The search utilized descriptors like "music therapy," "acoustic stimulation," and "tinnitus," leading to an initial selection of 552 articles. After reviewing abstracts, 211 articles were chosen for further evaluation, resulting in 48 full-text reviews, and ultimately, 23 articles published between 2005 and 2022 were included in the meta-analysis. Their findings suggest that MT is an effective treatment for tinnitus, as it stimulates both peripheral and central auditory pathways, as well as central para-auditory pathways associated with attention, concentration, memory, and emotions. However, the authors acknowledged that their meta-analysis showed a "very high heterogeneity among the articles", and that there is a "need for ongoing research to correct methodologies and assess whether a single treatment or multiple simultaneous or sequential treatment methods are necessary to make MT more effective."
Neurofeedback
Guillard et al (2021) noted that several clinical studies have shown that neurofeedback (NFB) has the potential to significantly improve the QOL of patients complaining of chronic subjective tinnitus. Yet the clinical applicability of such a therapeutic approach in the everyday practice has not been tested so far. In a single-arm, pilot study, these researchers examined the feasibility and effectiveness of a semi-automated NFB intervention by means of a portable device that eventually could be used by the patients at home on an everyday basis. The duration of setup procedures was minimized via the use of a dry electrodes electroencephalography (EEG) headset and an automated user-interface. According to a pre-determined power calculation, a homogeneous population of 33 subjects with strict inclusion criteria was enrolled. After inclusion, all patients underwent 10 NFB sessions lasting 50 mins each, over a period of 5 weeks and a 3-month follow-up period. According to previous studies, the NFB training aimed at increasing the alpha-band power (8 to 12 Hz) in the EEG power spectrum on the averaged signal of leads FC1, FC2, F3 and F4. THI was used as a primary outcome measure; secondary outcome measures were the VAS and the change of the alpha-band power within sessions and across training. Time-points of assessment were before intervention (T1), after intervention (T2) and at the 3-month follow-up (T3). Patient exhibited a clinically significant decrease of the THI score, with a 23 % decrease (n = 28) on average between T1 and T2 and a 31 % decrease (n = 25) between T1 and T3. A significant increase of the alpha-band power within sessions was observed. No significant increase of the alpha-band power across sessions was observed. For the 19 subjects where sufficient data were exploitable, a significant correlation was found between the evolution of the alpha-band training across sessions and the evolution of the THI between T1 and T2. The sessions were well-tolerated; and no AE was reported. The authors concluded that the findings of this study suggested that NFB has potential to suit everyday clinical practice with the objective to significantly reduce tinnitus intrusiveness. Moreover, these investigators stated that this study was a single-arm trial without control, and did not evaluate placebo effect; thus, the analyses and conclusion of the training performance should be taken in account with caution as only 72.5 % of the EEG recordings were exploitable, due to the choice of the use of dry EEG electrodes. These researchers stated that further investigation (placebo-controlled study) is needed to confirm or infirm these preliminary conclusions.
In a systematic review, Barrenechea et al (2023) examined the effectiveness of NFB treatment parameters in reducing the perception of tinnitus and in reducing the behavioral consequences triggered by the symptom. The data search was performed in Spanish and English on PubMed/MedLine, EBSCO Host, Embase, Scopus, CENTRAL, SpringerLink and OpenGrey databases. The systematic review was conducted according to the stages established by PRISMA and 5 studies were identified to be included in the qualitative analysis. All studies showed that NFB training for tinnitus decreased symptom perception and related consequences. At the neural level, there was an increase in the activity of the alpha wave and a decrease in the activity of delta, gamma and beta. The authors concluded that NFB has a modulating effect on brain activity patterns; however, although all the studies reported a decrease in the consequences related to the symptom at the behavioral level after treatment, due to the lack of development of this technique for the symptom and the characteristics of the studies reviewed, it could not be certainty of efficacy on behavioral and neurophysiological consequences.
Neuromonics Tinnitus Treatment
The Neuromonics Tinnitus Treatment (NTT) combines the use of acoustic stimulation with a structured program of counseling and support by a clinician specifically trained in tinnitus rehabilitation. The acoustic component has been designed to provide stimulation to auditory pathways deprived by hearing loss, engage with the limbic system, and allow intermittent, momentary tinnitus perception within a pleasant and relaxing stimulus, thereby facilitating desensitization to the tinnitus signal.
Davis and colleagues (2007) examined the effectiveness of NTT, enhanced with various modifications since previously reported trials, and tested the relative clinical effectiveness of two variations of the approach. In the first, intermittent tinnitus perception was facilitated throughout treatment via the use of a stimulus in which intensity peaks allowed the subjects' tinnitus perception to be completely covered up, whereas in the intensity troughs, their tinnitus was briefly discernible. In the second, subjects experienced little tinnitus perception while listening to the treatment for the first 2 months, then experienced intermittent perception. A total of 35 subjects with a predominantly moderate-to-severe level of tinnitus-related distress before treatment were randomly allocated into one of two treatment groups, corresponding to the two stage-based variations of the NTT. Subjects were provided with a high-fidelity personal sound player with earphones and an acoustic stimulus that had been spectrally modified according to their individual audiometric profile. They were instructed to use the acoustic stimulus for at least 2 hours per day, particularly at those times when their tinnitus was usually disturbing. Each group had equal amounts of clinician time for education, monitoring, and support.
At 2, 4, 6, and 12 months after commencing treatment, both groups displayed clinically and statistically significant improvements in tinnitus distress, awareness, minimum masking levels, and loudness discomfort levels. Improvements increased with time over the first 6 months of therapy, at which time 91% of all subjects across the two groups reported an improvement in tinnitus disturbance (as measured by the Tinnitus Reaction Questionnaire) of at least 40%, with a mean improvement of 65%. Furthermore, 80% of subjects at 6 months reported a level of tinnitus disturbance that was no longer clinically significant. There was some indication of a more consistent benefit over 12 months for the group that was provided initially with a high level of tinnitus interaction; however, inter-group differences were not statistically significant. A relation between reported treatment usage (hours per day) and clinical outcomes was observed, suggesting that a "dosage effect" may apply with the stimulus provided. The authors concluded that this study found that the NTT provides rapid and profound improvements to the severity of tinnitus symptoms and their effect on the subject's quality of life. This was a consistent effect, provided by a treatment that subjects reported as being pleasant to use. Both of the stage-based variations of the treatment that were tested in this study were shown to be successful in achieving these outcomes.
Davis and associates (2008) conducted another clinical study on the effectiveness of NTT. This treatment approach is provided as part of a structured rehabilitation program. In this study, patients who received the customized stimulus (NTT group) reported significantly greater and more consistent alleviation of tinnitus symptoms than did patients who participated in a counseling and support program with and without delivery of a broad-band noise stimulus (Noise + Counseling group and Counseling-Only group, respectively). After 6 months of treatment, 86% of the NTT patients met the minimum criterion for clinical success, defined as an alleviation of tinnitus disturbance of at least 40% (as judged by the Tinnitus Reaction Questionnaire score). By contrast, only 47% and 23% of the Noise + Counseling and Counseling-Only groups, respectively, reported a successful result according to this criterion. Mean improvements in tinnitus disturbance scores in the NTT, Noise + Counseling, and Counseling-Only groups were 66%, 22%, and 15%, respectively. The differences between the NTT group and the control groups were statistically significant. Significant differences were observed in other clinical outcomes. Patient reports of user acceptability were more consistently positive in the NTT group. It is unclear whether there was overlapping of patients in these two studies.
- small numbers of subjects, and
- short-term follow-up (not exceeding 12 months).
Moreover, it is unclear whether they were overlapping of patients in these two studies. These findings need to be validated by further investigation.
Oxytocin
In a pilot study, Azevedo and colleagues (2017) evaluated the potential of oxytocin as a tinnitus treatment. Two studies were performed. Study 1 was a long-term open pilot study, while study 2 investigated short-term effects with a double-blinded placebo-controlled cross-over study. In study 1, a total of 15 patients were investigated over a 10-week period in an open pilot study. In study 2, 16 patients were included in a placebo-controlled cross-over trial to investigate short-term effects following a single dose. For the long-term study (study 1), analysis of variance revealed a significant decrease in tinnitus sensation, both for the THI and Clinical Global Impression (CGI). Also, the short-term effects in study 2 revealed a significant reduction of tinnitus because of the oxytocin nasal spray as measured with the VAS and the CGI Scale. The authors conclude that these preliminary studies demonstrated that oxytocin may represent a helpful tool for treating tinnitus; and further larger controlled studies are needed.
Ozone Therapy
De Faria and colleagues (2022) noted that tinnitus is a frequent complaint in otorhinolaryngology. Numerous therapeutic interventions and studies claimed success in the treatment of tinnitus, but the cure remains undefined. However, ozone therapy has been suggested as potential treatment for tinnitus. In a systematic review, these investigators examined the effectiveness of ozone therapy in the treatment of tinnitus. They carried out a systematic search in Medline, Web of Science, Cochrane Library, Science Direct, Scopus, Google Scholar, Embase and LILACS. Data were processed by 2 independent reviewers. Only systematic reviews, RCTs, observational studies and case series published in English or Spanish with no date limit that evaluated the use of ozone therapy for the treatment of tinnitus were included. From 264 references retrieved after duplicates removal, 260 articles were excluded according to the pre-established selection criteria. The assessed articles were then subjected to risk of bias analysis, and 1 of them was excluded. The authors concluded that high-level evidence, such as well-conducted randomized clinical trials, are still needed to confirm the safety and effectiveness of this therapy.
Peripheral Muscle Magnetic Stimulation
Vielsmeier and colleagues (2018) stated that while brain stimulation techniques have been examined as therapeutic options for chronic tinnitus for many years, they have recently been extended to multi-modal treatment approaches. As chronic tinnitus is often accompanied by co-morbid muscular tension in the neck and back, these researchers performed a 1-arm pilot study to examine the feasibility of a new multi-modal therapeutic approach. Repetitive peripheral magnetic stimulation (rPMS) of the back was performed before and after each session of rTMS of the brain. Data of 41 patients were analyzed, all of which were treated with 10 sessions of rTMS of the left prefrontal and left temporo-parietal cortex followed by rPMS of the neck and back muscles. Tinnitus severity was measured using the tinnitus questionnaire (TQ). Neck pain was assessed using the neck pain and disability scale (NPAD). The new treatment approach was feasible and well accepted by the majority of patients. However, the overall patient group did not improve significantly in either of the questionnaires. If patients were divided in different subgroups depending on whether they were suffering from neck pain or somatosensory tinnitus, explorative post-hoc tests suggested differential effects: patients with both neck pain and somatosensory tinnitus had better outcomes than patients without those conditions or with neck pain only. This was true for both the TQ and the NPAD. This effect was of transient nature though: the TQ score went back to its baseline level after a follow-up period of 12 weeks. Based on these findings, the authors recommended that in studies that examine interventions of tinnitus targeting somatosensory afferents patients should be stratified according to somatic co-morbidities as well as somatosensory influence on the tinnitus percept. Moreover, they stated that the combination of 2 techniques – such as rPMS plus rTMS – is challenging to explore, as the complexity is increased by additional aspects such as the temporal relationship between peripheral and central stimulation. Consequently, future studies should try to concentrate on subgroup-specific effects of different treatment strategies or, more generally, on individualized treatment programs considering the very specific combination of possible causes and/or tinnitus-related alterations of a particular patient.
The authors stated that this was the first study to report combined rTMS and rPMS for the treatment of patients suffering from chronic subjective tinnitus. As it was designed as a pilot study, there were some limitations that should be kept in mind when interpreting the results. First, in order to examine the feasibility of the combined treatment, a 1-arm trial with no control group was chosen. Second, these investigators chose a well-studied standard rTMS protocol in order to combine it with rPMS treatment. This standard rTMS protocol consisted of left-hemispherical treatment and did not account for tinnitus laterality. The question if and how tinnitus laterality should be considered for the choice of the "right" rTMS treatment protocol has partly been examined for unilateral tinnitus but is still an open question for bilateral tinnitus or tinnitus which is perceived inside the head. A recent study indicated that tinnitus laterality has no association with rTMS response. Although important, it was not part of the current study's hypothesis to add to this question. Third, the exploratory analyses were done post-hoc, which meant that also the subdivision of patients to the different subgroups was done post-hoc. Thus, the subgroups were not matched with respect to demographical and clinical characteristics.
Radiofrequency Lesion of the Superior Cervical Sympathetic Ganglion
Koning et al. (2016) examined the effectiveness of radiofrequency lesioning of the superior cervical sympathetic ganglion for patients with tinnitus. This was a retrospective long-term clinical review of patients with tinnitus treated with a blockade of the superior cervical sympathetic ganglion. The subjects were 366 consecutive patients who visited the DC Klinieken in Almere and Amsterdam from January 2010 to January 2014 for consultations regarding their tinnitus, which had persisted for 1 month or longer. Data were recorded from patients whose charts were reviewed retrospectively to identify those treated with a blockade of the superior cervical sympathetic ganglion for tinnitus. An independent observer conducted a long-term follow-up assessment of the therapy through telephone interviews. Relief of tinnitus at the 7-week follow-up was achieved in 64% of the patients treated with a radiofrequency lesion of the superior cervical sympathetic ganglion after a positive test blockade of this structure. Two years after the treatment, maintenance of tinnitus relief occurred in almost 40% of the patients with a follow-up period of 2 years or longer. The authors concluded that radiofrequency lesioning of the superior cervical sympathetic ganglion may be a useful alternative for patients with tinnitus who do not respond to conventional therapy. However, these preliminary findings need to be validated by well-designed studies.
Koning and Meulen (2019) examined the effectiveness of pulsed radiofrequency (PRF) of the C2 dorsal root ganglion (DRG) in the treatment of patients with tinnitus and surveyed the parameters related to long-term benefits. Participants included 61 consecutive patients who attended the authors’ facility from October 2016 to October 2018 for discussions about their tinnitus, which had persisted for 1 month or more, and were treated with PRF of the C2 DRG. Clinical information for these patients was recorded, and an independent observer evaluated the long-term impact of the treatment by phone. Among patients with tinnitus that persisted for 1 month or more, 15 (25%) experienced a reduction in their tinnitus after PRF of the C2 DRG. At 13.5 months following treatment, 50% of the initially effective treated patients still reported benefits. Adverse events related to the PRF of the C2 dorsal root ganglion at the 7-week follow-up included an increase in the intensity of tinnitus in 7% of the patients. In patients under the age of 43 years at the time of tinnitus onset, 45% experienced a reduction in their tinnitus at 7 weeks following treatment with PRF of the C2 DRG. The authors concluded that PRF of the C2 DRG could significantly reduce the intensity of tinnitus for the long term in 25% of the patients without serious adverse effects. Moreover, they stated that a prospective follow-up study with a larger cohort is needed to confirm these findings. The authors noted that the main drawbacks of the study were its retrospective design and small sample size, as only 25% of participants experienced positive effects from the treatment.
Sequential Phase Shift Sound Cancellation Treatment
Sequential phase shift sound cancellation is a novel treatment for predominant-tone tinnitus. It entails the use of a phase-shift sound cancellation protocol in which a patient’s tinnitus is first identified as to frequency and amplitude. Then, a signal, 6 degrees out-of-phase with the identified tinnitus signal, is fed sequentially (6 degrees, 12 degrees, etc.) into the patient’s headphones for 30 seconds each for 30 minutes, or until 360 degrees is achieved. Available evidence on the effectiveness of this approach has mainly been in abstract forms (Noik, 2005; Choy and Kaminow, 2005; Lipman et al, 2006). The only published full-length paper on this subject is by Lipman and Lipman (2007) who assessed phase shift treatment for predominant tone tinnitus in a prospective, single-blinded, cross-over study. A total of 61 patients participated in 2 weeks of control and 2 weeks of phase shift treatment. Outcome measures included frequency and intensity matching, pre- and post-treatment tinnitus handicap inventory (THI) scores, and patient diaries. Initial volume comparisons showed a strong relationship between treatment and decrease in tinnitus intensity, with 57% of patients achieving successful treatment. Thirty-seven percent decreased by one THI grade, 5% by two. Utilizing patient diaries, 42% of patients reported periods of complete residual inhibition (CRI) ranging from 1 hour to 7 days (average of 2 days). No periods of CRI were reported in control weeks. The authors concluded that phase shift treatment significantly benefited the majority of patients. These findings suggested that this device may be a valuable tool. They noted that further long-term studies with home therapy are needed.
In a double-blind, cross-over, randomized-controlled trial, Heijneman et al. (2012) compared the effectiveness of the treatment of tinnitus with a phase-shifting pure tone to that of the same tone treatment without phase shifting. A total of 22 patients with predominantly tonal tinnitus underwent both intervention and control treatments. Each treatment consisted of three 30-minute sessions in 1 week. The control treatment was identical to the intervention treatment, except that the stimulus was a pure tone without phase shifting. Questionnaires, tinnitus loudness match, and annoyance and loudness ratings were used to measure treatment effects. Pure-tone treatment and phase-shift treatment had no significant effect on tinnitus according to questionnaires (Tinnitus Handicap Index, Tinnitus Reaction Questionnaire, Hospital Anxiety and Depression Scale, and Maastricht Questionnaire), audiological matching procedures, and loudness and annoyance ratings of tinnitus. Furthermore, phase-shift treatment showed no additional significant improvement in comparison with pure-tone treatment. Changes in questionnaire scores due to pure-tone and the phase-shift treatment were correlated. The authors concluded that on average across the group, both treatments failed to demonstrate a significant effect. Both treatments were beneficial for some patients. However, a positive effect was not demonstrated that could be attributed to the periodic shifting of the phase of the stimulus tone.
Thus, there is currently insufficient evidence to support the use of sequential phase shift sound cancellation treatment for tinnitus.
Sigmoid Sinus Resurfacing for the Treatment of Pulsatile Tinnitus
Santa Maria (2013) reported a case of sigmoid sinus dehiscence presenting with pulsatile tinnitus and treated successfully with resurfacing. This patient presented with pulsatile tinnitus due to sigmoid sinus dehiscence. This was successfully treated using only soft tissue resurfacing. The author concluded that sigmoid sinus dehiscence is a rare but treatable cause of pulsatile tinnitus. It can occur in the absence of a diverticulum, and is not necessarily limited to the transverse sigmoid junction. When resurfacing, care must be taken not to significantly alter the extra-luminal diameter of the sigmoid in a dominant sinus, as this raises the risk of post-operative hydrocephalus.
Song and colleagues (2015) noted that pulsatile tinnitus (PT) caused by venous sinus diverticulum is a relatively common, potentially incapacitating condition. Although treatment via an external approach or endovascular coiling has been reported, much remains unknown about the possible pathophysiological mechanisms and appropriate management of PT. These investigators reviewed their case series of PT resulting from either sigmoid sinus diverticulum (SSD) or middle cranial fossa venous sinus diverticulum (MFD-VS) and discussed the possible pathophysiological mechanisms and desirable therapeutic options. A total of 4 PT patients with either SSD or MFD-VS were treated with trans-mastoid resurfacing. In 1 case, a revision operation was performed as a result of recurrence of PT 4.5 years after the initial operation. The medical records and temporal bone imaging findings were retrospectively reviewed. PT was resolved in all cases immediately after trans-mastoid resurfacing, but 1 patient in whom bone wax was used for initial resurfacing experienced PT 4.5 years later. The PT was successfully managed with revision resurfacing with autologous bone chips/bone cement. In the other cases, the resolution of PT lasted throughout a median follow-up of 5.75 years. Notably, 2 of 4 cases had pre-operative low-frequency hearing loss (LFHL) and experienced immediate post-operative improvement in LFHL. The authors concluded that PT resulting from either SSD or MFD-VS can be treated successfully with trans-mastoid resurfacing of the venous wall. Pre-operative ipsilesional LFHL and the improvement of hearing threshold after surgical intervention may be pre-operative and post-operative surrogate objective signatures of PT. To ensure the resolution of symptoms, secure reconstruction with firm materials and long-term follow-up are mandatory.
Zeng and associates (2016) evaluated clinical characteristics and presented surgical outcomes of PT caused by sigmoid sinus wall dehiscence (SSWD). This study retrospectively reviewed 34 patients with PT who were diagnosed with SSWD in the authors’ institution between December 2008 and July 2013. Among them, 27 patients underwent SS wall reconstruction (SSWR; surgery group) and 7 patients refused surgery (non-surgery group). Pre-operative data were obtained from the patients’ medical records. All patients were followed-up regularly for at least 25 months. Pre-operative and post-operative CT angiography (CTA) images were compared. Student’s t-tests were used to compare age, body mass index (BMI), and pre-operative THI scores between the surgery and the non-surgery groups and to compare pre- and follow-up THI scores. There was no significant difference in age, BMI, or pre-operative THI scores between groups. Following surgery, 14 patients had complete resolution, 5 had partial resolution, 7 experienced no change and PT was aggravated in 1 patient. The difference between pre-operative and post-operative THI scores was significant. No severe complications were found post-operatively. Comparison of the pre-operative and post-operative CTA images revealed that remnant unrepaired dehiscences were the cause of unsatisfactory outcomes following surgery. In the non-surgery group, PT remained largely unchanged. The authors concluded that SSWR was a safe and effective treatment for PT caused by SSWD. They stated that it was imperative that all regions of the dehiscence were sufficiently exposed and re-surfaced during surgery.
Raghavan and co-workers (2016) stated that trans-mastoid SSWDR is a surgical technique increasingly used for the treatment of PT arising from SS wall anomalies. The imaging appearance of the temporal bone following this procedure has not been well-characterized. These researchers evaluated the post-operative imaging appearance in a group of patients who underwent this procedure. The medical records of 40 consecutive patients who underwent trans-mastoid SSWD were reviewed; 13 of 40 patients underwent post-operative imaging; 19 CT and 7 magnetic resonance imaging (MRI) examinations were assessed for the characteristics of the materials used for reconstruction, the impact of these on the adjacent SS, and complications. Tinnitus resolved in 38 of 40 patients; 9 patients were imaged post-operatively for suspected complications, including dural sinus thrombosis, facial swelling, and wound drainage; 2 patients underwent imaging for persistent tinnitus, and 2, for development of tinnitus on the side contralateral to the side of surgery. The materials used for reconstruction (NeuroAlloderm, HydroSet, bone pate) demonstrated characteristic imaging appearances and could be consistently identified. In 5 of 13 patients, there was extrinsic compression of the SS by graft material. Dural sinus thrombosis occurred in 2 patients. The authors concluded that the imaging findings following SSWR were characteristic. Graft materials may result in extrinsic compression of the SS, and this finding may be confused with dural venous thrombosis. Awareness of the imaging characteristics of the graft materials used enables this differentiation.
Tian and associates (2017) noted that sigmoid sinus cortical plate dehiscence (SSCPD) is common in PT patients, and is treated through SSCPD resurfacing surgery in clinic, but the bio-mechanism is unclear. These researchers clarified the bio-mechanism of PT sensation induced by SSCPD, and quantify the relationship of cortical plate (CP) thickness and PT sensation intensity. It was hypothesized that SSCPD would induce PT through significantly amplifying sigmoid sinus (SS) venous sound in this study. Finite element (FE) analysis based on radiology data of typical patient was used to verify this hypothesis, and was validated with clinical reports. In cases with different CP thickness, FE simulations of SS venous sound generation and propagation procedure were performed, involving SS venous flow field, vibration response of tissue overlying dehiscence area (including SS vessel wall and CP) and sound propagation in temporal bone air cells. It was shown that SS venous sound at tympanic membrane was 56.9 dB in SSCPD case and -45.2 dB in intact CP case, and was inaudible in all thin CP cases. The authors concluded that SSCPD would directly induce PT through significantly amplifying SS venous sound, and thin CP would not be the only pathophysiology of PT. This conclusion would provide a theoretical basis for the design of SSCPD resurfacing surgery for PT patients with SSCPD or thin CP.
Wang and co-workers (2017) stated that although studies demonstrated 4 to 20 % of patients with PT have associated SS anomalies, no consensus exists regarding optimal management. These investigators performed a systematic review exploring surgical and endovascular intervention of PT caused by SS anomalies. A systematic review was performed using the PRISMA guidelines for reporting of results, with a target population encompassing patients with PT and either SSD or sigmoid wall dehiscence. From an initial search yielding 74 articles, 21 manuscripts met inclusion criteria. Of 139 patients, 90.4 % were women; mean age was 39.0 years. Diagnosis was SSD/aneurysm in 47.5 % of patients, sigmoid sinus dehiscence in 35.3 % of patients, and both in 17.3 %. Sigmoid sinus wall reconstruction/resurfacing (SSW R/R) was used in 91.4 % and endovascular procedures in 7.9 % of patients. Post-operative recurrence was 3.5 % (mean follow-up of 21.1 months). Although there was no association between resolution rate and age or sex, right-sided PT resolved at a higher rate. For every increase in body mass index (BMI) by 1 kg/m, the odds of PT resolution increased 9.2 %. The authors concluded that PT as a result of SSD, aneurysms, and dehiscence is a rare, but largely treatable condition. Available interventions include SSW R/R, endovascular intervention, and cardiac U-clip techniques. In SSW R/R, bone pate, unspecified soft-tissue graft, and bone cement had the highest rates of PT resolution. While temporalis fascia and autologous bone chips were the materials most commonly used, they had significantly lower rates of PT resolution compared with the other materials, with the exception of auricular cartilage and bone cement. Most episodes of recurrence were resolved with medical management or a revision procedure.
Yeo and colleagues (2018) noted that jugular bulb and SS anomalies are well-known causes of vascular PT. Common anomalies reported in the literature include high-riding and/or dehiscent jugular bulb, and sigmoid sinus dehiscence. However, cases of PT due to diverticulosis of the jugular bulb or SS were less commonly encountered, with the best management option yet to be established. In particular, reports on surgical management of PT caused by jugular bulb diverticulum have been lacking in the literature. These investigators reported 2 cases of PT with jugular bulb and/or SSD, and their management strategies and outcomes. In this series, these researchers described the first reported successful case of PT due to jugular bulb diverticulum that was surgically-treated. Two patients diagnosed with either jugular bulb and/or SSD, who had presented to the Otolaryngology clinic with PT between 2016 and 2017, were studied. Demographic and clinical data were obtained, including their management details and clinical outcomes. Two cases (1 with jugular bulb diverticulum and 1 with both SS and jugular bulb diverticula) underwent surgical intervention, and both had immediate resolution of PT post-operatively. This was sustained at subsequent follow-up visits at the out-patient clinic, and there were no major complications encountered for both cases intra- and post-operatively. The authors concluded that trans-mastoid reconstruction/resurfacing of jugular bulb and SSD with/without obliteration of the diverticulum was a safe and effective approach in the management of PT arising from these causes.
In a retrospective, case-series study, Lee and associates (2019) discussed the possible pathophysiologic mechanism of PT perception due to high jugular bulb with bony dehiscence (HJBD) and its improvement after the dehiscent jugular bulb (JB) resurfacing using bone cement, and described the efficacy of an objective measure of PT using trans-canal sound recording and spectro-temporal analysis (TSR/STA). A total of 3 patients underwent trans-tympanic resurfacing after the source of PT was confirmed by temporal bone imaging and TSR/STA. Improvement of symptom and the changes in the TSR/STA were analyzed. In the first case, a revision operation was performed due to slightly improved but persistent PT after initial resurfacing with bone pate and a piece of conchal cartilage. Revision trans-tympanic JB resurfacing was performed in this case using bone cement, and PT resolved immediately after the surgery. In the second and third cases, PT resolved completely, or was much abated, immediately after trans-tympanic resurfacing with bone cement. The TSR/STA also revealed improvement of PT. The median follow-up duration was 28 months, and all 3 patients remained asymptomatic or much improved compared with their pre-operative status. The authors concluded that trans-tympanic resurfacing with bone cement, reinforcing the dehiscent JB to reduce focal turbulent flow, was a simple and effective surgical therapeutic option in patients with PT due to HJBD. In patients with HJBD, the objective measurement of PT by TSR/STA may be of help in selecting appropriate surgical candidates and objective evaluation of the treatment outcome.
Sound Therapy / The Otoharmonics Levo System Sound Therapy
In a RCT, Theodoroff and colleagues (2017) examined if a customized stimulus from the Otoharmonics Levo System reduces tinnitus perceptions and reactions for people with bothersome tinnitus. A total of 60 subjects were randomized to 1 of 3 groups that used sound therapy devices during sleep that differed in their acoustic stimulus: tinnitus-matched (TM), noise stimulus (NS), and 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. Average tinnitus reactions and perceptions improved across treatment groups. These investigators were at least 87 % certain that treatment with TM or NS reduced mean TFI compared to treatment with BSG, with an estimated relative efficacy of 4.5 to 5 points greater reduction. They were at least 95 % certain that treatment with TM resulted 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. The authors concluded that the findings of this study offered 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. Moreover, they stated that the magnitude of these relative effects and the extent to which they generalize to other clinical environments and patient populations require additional study; future controlled trials are needed to determine if these results are replicable and to evaluate additional variables and patient factors that would inform clinical practice.
The authors stated that this study had several drawbacks. Because of the nature of the sound therapy devices used in this study, blinding was not possible nor was it feasible to create a true placebo device. All participants knew up front that 2 groups would be receiving custom earbuds for devices to be used at ear level, whereas the third group was to use a sound therapy device that played sounds through a BSG. It was possible that participants who received custom earbuds to be used with the in-ear devices (TM and NS groups) were influenced by receiving something "special," and the degree that might have contributed to the outcomes of this study is unknown. The BSG and NS groups served as control groups, but not in the same manner as a placebo-controlled group; therefore, it was not possible to quantify how much of a placebo effect might also have contributed to these outcomes. When interpreting these findings, it is important to recognize that this study used self-reported outcomes. Just the act of participating in a clinical trial can have a positive effect on outcomes, regardless of the treatment received. It was not uncommon for individuals with tinnitus to report fluctuations in their tinnitus perceptions, and no established standard exists to assess the reliability of subjective ratings of tinnitus loudness. Finally, this study was not designed to look at sustainability of improvement. No measurements were performed at any time point after the "end of treatment" to determine how long any reported benefit continued. Future prospective studies involving the TM device should include assessments after 3 months to investigate how long possible benefit is sustained. Another limitation was the unknown generalizability of these results to tinnitus patients seen in the clinic. All participants in the current study were given their respective devices free of charge within the context of a research study. In a clinical setting, tinnitus patients may have different expectations than in a research study and would likely take into account the cost of different sound therapy device options and consider the cost-to-benefit ratio of each. The economic value compared to expected benefit of a therapy device is something that would commonly be discussed and factored into the decision-making process and is not something this study can address.
Lv and colleagues (2020) stated that to determine the neural mechanism underlying the effects of sound therapy on tinnitus, they hypothesized that sound therapy may be effective by modulating both local neural activity and functional connectivity (FC) that is associated with auditory perception, auditory information storage or emotional processing. In a prospective, observational study, 30 tinnitus patients underwent resting-state functional MRI scans at baseline and after 12 weeks of sound therapy; and 32 age- and gender-matched healthy controls also underwent 2 scans over a 12-week interval; 30 of these healthy controls were enrolled for data analysis. The amplitude of low-frequency fluctuation (ALFF) was analyzed, and seed-based FC measures were shown to significantly alter spontaneous local brain activity and its connections to other brain regions. Interaction effects between the 2 groups and the 2 scans in local neural activity as assessed by the ALFF were observed in the left para-hippocampal gyrus and the right Heschl's gyrus. More importantly, local functional activity in the left para-hippocampal gyrus in the patient group was significantly higher than that in the healthy controls at baseline and was reduced to relatively normal levels after treatment. Conversely, activity in the right Heschl's gyrus was significantly increased and extended beyond a relatively normal range after sound therapy. These changes were found to be positively correlated with tinnitus relief. The FC between the left para-hippocampal gyrus and the cingulate cortex was higher in tinnitus patients after treatment. The alterations of local activity and FC in the left para-hippocampal gyrus and right Heschl's gyrus were associated with tinnitus relief. Resting-state functional MRI could provide functional information to explain and “visualize” the mechanism underlying the effect of sound therapy on the brain. The authors concluded that they proved their hypothesis that sound therapy is effective by modulating both local neural activity and FC, which is associated with auditory perception, auditory information storage or emotional processing. The alterations of local activity and FC in the left para-hippocampal gyrus and right Heschl's gyrus were associated with tinnitus relief. Increased levels of FC between the left para-hippocampal gyrus and cingulate cortex may serve as neural feedback routes within the limbic system.
The authors stated that several issues need to be further addressed. First, ALFF is a widely used analytic method; however, the concept that ALFF reflects local brain activity may not be universally accepted. Furthermore, FC measurements were based on the selection of regions of interest (ROIs). In this study, only 2 brain regions were selected as seeds according to the results of voxel-wise ALFF calculation, potentially explaining the limited number of significantly altered FCs observed. Second, altered FC values observed within and between neural networks should be further discussed. More studies using different analytical methods may examine the effect of sound therapy on different factors. Third, the tinnitus patients enrolled in this study did not suffer from hearing loss, which was not representative of most patients with tinnitus. Additional auditory brainstem response (ABR) tests may better characterize hearing impairment. It may be more helpful to analyze non-responders to better characterize the mechanism of sound therapy. It may also be helpful to analyze patients with a wider range of THI scores or patients whose disease severity was evaluated by other methods (e.g., the VAS, tinnitus loudness, the tinnitus functional index). Furthermore, patients with sham treatment may be needed to account for the placebo effect of sound therapy.
In a network meta-analysis (NMA), Liu and colleagues examined the acceptability and effectiveness of different sound therapies for the management of patients with tinnitus. These investigators carried out a literature search to identify articles in Embase, PubMed/Medline, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Chinese Biomedical Literature, and Wanfang and Weipu from inception to April 1, 2021. The THI, TQ, and effective rate were used to evaluate perceived tinnitus suppression following treatment. These researchers used Review Manager 5.4 for the standard meta-analysis; R 4.0.4 and Stata 15.1 were used for the NMA and the publication bias and sensitivity analyses. The effect estimates of the direct comparisons (when available) were very similar to those of the NMA. Overall, sound stimulation alone performed better than medication alone, educational consultation alone, and no treatment. Combination therapy, such as sound stimulation plus educational consultation and sound stimulation plus drug therapy, yielded significantly better outcomes with regard to the alleviation of tinnitus than individual treatments. The authors concluded that this was the 1st NMA to evaluate and compare the effectiveness of different sound therapies for the management of tinnitus. It may help inform the selection of sound therapy and the development of guidelines in clinical practice. Moreover, these researchers stated that future studies of sound therapy with larger sample sizes and longer follow-up periods involving multiple medical centers are needed to improve the current evidence.
Telerehabilitation Interventions
In a systematic review, Demoen et al (2023) provided an overview of the research concerning the effectiveness of telerehabilitation interventions for self-management of tinnitus. This systematic review followed the PRISMA guidelines. Studies were eligible for inclusion if subjects were adult patients with complaints of primary subjective tinnitus and the study intervention comprised any possible telerehabilitation form for the self-management of tinnitus complaints. A search for eligible studies was conducted on PubMed, ScienceDirect, Scopus, Web of Science, and Cochrane Library. The Cochrane Risk of Bias 2 tool was used to the evaluate risk of bias. A total of 29 studies were found eligible, and of these, 5 (17 %) studied multiple telerehabilitation forms. Internet-based CBT with guidance by a psychologist or audiologist was examined in 17 studies (n = 1,767), internet-based CBT without guidance was examined in 4 studies (n = 940), self-help manuals were examined in 1 study (n = 72), technological self-help devices were examined in 2 studies (n = 82), smartphone apps were examined in 8 studies (n = 284), and other internet-based interventions were examined in 2 studies (n = 130). These rehabilitation categories were proven to be effective in decreasing tinnitus severity and relieving tinnitus distress as measured by tinnitus questionnaires such as TFI, THI, or Tinnitus Reactions Questionnaire (TRQ). However, drop-out rates were often high (range of 4 % to 71.4 %). All studies reported between some concerns and high concerns of risk of bias, resulting in low-to-moderate certainty levels. The authors concluded that there is low-to-moderate quality evidence that telerehabilitation interventions effectively reduce tinnitus severity and distress. These interventions form a possible tool to improve the self-management capacities of the patient and the accessibility of tinnitus care as a replacement or an addition to in-person care. Nevertheless, barriers such as lack of time, engagement, motivation, and openness of the patient causing high drop-out should be considered. Moreover, these researchers stated that factors such as lack of time, engagement, motivation, and openness of the patient resulted in participant drop-out and should be considered. Furthermore, it was noted that all included studies showed some-to-high concerns of the risk of bias (RoB) resulting in low-to-moderate certainty of the statements concerning the effectiveness of the telerehabilitation treatment forms. These researchers stated that future research should consider limiting the RoB and should further examine which factors are most likely to cause the lack of compliance and how clinicians can counteract these factors.
The authors stated that this systematic review had several drawbacks. First, all included studies scored some-to-high concerns of RoB. As a result, the included studies were of low-to-moderate certainty. Second, a comparison of effectiveness among studies was not feasible owing to the variety of questionnaires used to measure the level of tinnitus complaints, severity, or distress. Third, some crucial confounding parameters were not considered by all studies. Only a minority of studies concerning internet-based CBT (iCBT) in this review observed the proportion of participants with hearing loss or how many patients used hearing aids. However, how these studies define the presence of hearing loss was often not clarified. The studies concerning other telerehabilitation forms such as self-help manuals, self-help devices, and smartphone apps did seldom define the percentage of participants with hearing loss. Hearing loss is an important risk factor for developing tinnitus. Fourth, there were patients with audiometrically normal hearing who experienced tinnitus; however, tinnitus severity and distress are known to be significantly worse in patients with tinnitus with hearing loss in comparison with patients with tinnitus without hearing loss. Thus, hearing loss might be an important confounding variable to consider. An audiometric examination of patients with tinnitus is therefore of value when researching patients with tinnitus.
Tinnitus Retraining Therapy
Tinnitus retraining therapy (TRT) is a neurophysiological approach centering on behavioral retraining of the associations induced by perception of tinnitus. TRT uses a combination of low-level broad-band noise along with counseling to achieve the habituation of tinnitus. The goal is to become unaware of the tinnitus unless it is consciously focused on and to remain unbothered by it, even when aware of it.
- the actual spectrum of the emitted noise,
- the ear canal resonance of the patient, and
- the hearing sensitivity of the patient.
Furthermore, a study stated that methodological limitations of the research published to date preclude any claims about the efficacy of TRT at the present time (Wilson et al., 1998). A technology assessment prepared for the Wessex Institute for Health Research and Development (Leal and Milne, 1998) concluded that the available case series are inadequate, owing to problems of methodology, and that there is no evidence to suggest that TRT is effective in the treatment of debilitating tinnitus in adult patients.
Kroener-Herwig et al. (2000) stated that there is no published study evaluating Tinnitus Retraining Therapy (TRT) using a randomized group design, even though this is the only design capable of providing valid information on the empirical status of a therapy. They concluded that the praise of TRT as the most promising therapy for chronic tinnitus can only be regarded as premature, and the claims of its effectiveness by its advocates await scientific corroboration. Randomized controlled clinical studies that include no-treatment and placebo groups are needed to ascertain the effectiveness of TRT in managing patients with tinnitus.
An assessment by the Washington Department of Labor and Industries Office of the Medical Director (Wang, 2004) concluded that "[d]ue to the lack of prospective trials with comparison groups, the efficacy of TRT for subjective tinnitus has not been established. Therefore, TRT is considered investigational and controversial."
A systematic review of the evidence for tinnitus treatments by BMJ Clinical Evidence concluded that tinnitus training therapy is of "unknown effectiveness" (Savage et al., 2011).
Hiller and Haerkotter (2005) reported that noise generators had benefits for persons with tinnitus. However, post-hoc analysis revealed benefits in a subgroup of tinnitus patients with hyperacusis. They stated that this finding would need to be replicated in a prospective, well-controlled study to evaluate sound generators in hyperacusis.
Topographical Filter Dermal Patch
Ahnblad (2017) stated that a new topographical filter in a dermal administration patch that organizes water molecules has been suggested as an alternative treatment for manifested tinnitus. In a pilot study, these researchers evaluated the safety and effectiveness of this dermal patch in patients with tinnitus. A total of 12 patients were included (10 completed) in an open study all receiving treatment with daily changed patches. The objectives were to evaluate safety and performance of the patch during and after treatment. The primary objective was to evaluate the tinnitus severity (by Tinnitus Severity Questionnaire, TSQ) and tinnitus annoyance (by VAS). The secondary objective was to evaluate if the patch could improve the patient's quality of life (by SF-36 QOL questionnaire) and sleep initiation time (self-rated). At visit 4, after 21 days of treatment, an improvement (decrease in TSQ score) was seen in 5 responder patients, which was sustained at the post-treatment visit. A marginal increase in TSQ score was seen also initially in 5 non-responder patients, 4 of which were responders post-treatment. The rated tinnitus annoyance, quality of life (QOL) and sleep initiation time did not show significant changes. The safety evaluation did not present any safety concerns. The authors concluded that the findings of this small pilot study indicated that it can be reasonable to recommend on a risk-benefit and safety perspective treatment with the dermal patch to patients with tinnitus as a consumer product based on the lack of other effective alternative treatment. Moreover, they stated that further and larger studies, and also proven experience, are needed for stronger evidence.
Transcranial Magnetic Stimulation
Repetitive transcranial magnetic stimulation (rTMS) treatment consists of low-level electrical stimulation emitted from an electrostimulator device placed on the earlobes or behind the ears.
Clinical, neurophysiological, and neuroimaging data suggest that chronic tinnitus resembles neuropsychiatric syndromes characterized by focal brain activation. Low-frequency repetitive transcranial magnetic stimulation (rTMS) has been proposed as a method for treating brain hyperexcitability disorders by reducing cortical excitability. Kleinjung et al. (2005) examined the effects of rTMS on patients with chronic tinnitus (n = 14). Increased metabolic activation in the auditory cortex was verified in all patients. After 5 days of rTMS, a highly significant improvement in the tinnitus score was found, whereas the sham treatment did not show any significant changes. The treatment outcome after 6 months still demonstrated a significant reduction in the tinnitus score. The authors concluded that these preliminary results showed that neuro-navigated rTMS offers new possibilities in the understanding and treatment of chronic tinnitus. The findings of this study need to be verified by further investigation with a larger sample size and long follow-up.
Pridmore et al. (2006) examined the literature and considered the potential for TMS as a treatment for patients with tinnitus. These researchers noted that a small number of studies have suggested that TMS may be effective in the treatment of tinnitus. There is a good theoretical basis and early research evidence suggesting that TMS may have treatment potential in tinnitus. Moreover, they stated that further, larger studies are necessary to ascertain the effectiveness of this approach.
In a randomized, placebo-controlled (sham stimulation) crossover pilot study, Smith et al. (2007) evaluated the effectiveness of neuro-navigated rTMS and its effects on attentional deficits and cortical asymmetry in 4 patients with chronic tinnitus using objective and subjective measures and employing an optimization technique refined in their laboratory. Patients received 5 consecutive days of active, low-frequency rTMS or sham treatment (using a 45-degree coil-tilt method) before crossing over. Subjective tinnitus was assessed at baseline, after each treatment, and 4 weeks later. Positron emission tomography/computed tomography (PET/CT) scans were obtained at baseline and immediately after active treatment to examine changes in cortical asymmetry. Attentional vigilance was assessed at baseline and after each treatment using a simple reaction time test. All patients had a response to active (but not sham) rTMS, as indicated by their best tinnitus ratings; however, tinnitus returned in all patients by 4 weeks after active treatment. All patients had reduced cortical activity visualized on PET immediately after active rTMS. Mean reaction time improved (p < 0.05) after active but not sham rTMS. The authors concluded that rTMS is a promising treatment modality that can transiently diminish tinnitus in some individuals, but more studies are needed to determine the optimal techniques needed to achieve a lasting response. It is unclear if the improved reaction times were caused by tinnitus reduction or a general effect of rTMS. PET/CT scans immediately after treatment suggest that improvement may be related to the reduction of cortical asymmetry associated with tinnitus.
Khedr et al. (2008) compared the effect of different frequencies of rTMS (1 Hz, 10 Hz, 25 Hz, and sham (occipital, 1 Hz)), given daily over the left temporo-parietal cortex for 2 weeks, on 66 patients with chronic tinnitus randomly divided into four treatment groups. Patients were assessed using the Tinnitus Handicap Inventory (THI), self-ratings of symptoms, and audiometric measures of residual inhibition before, immediately after 2 weeks of treatment, and monthly thereafter for 4 consecutive months. There were no significant differences in baseline measures between the four groups of patients. A 2-factor ANOVA revealed a significant "rTMS" x "time" interaction for all measures. This was because real rTMS produced greater improvement than sham. However, there was no significant difference between the responses to different frequencies of rTMS. The response to rTMS depended on the duration of tinnitus: patients who had tinnitus for the longest period of time were the least likely to respond to treatment. The authors concluded that daily sessions of rTMS over the temporo-parietal cortex may be a useful potential treatment for tinnitus.
In a pilot study, Lee and colleagues (2008) examined the effectiveness of rTMS in veterans with debilitating tinnitus. A total of 8 patients received 5 consecutive days of rTMS (0.5 Hz, 20 minutes) to the left temporo-parietal area. Outcomes were measured by means of THI before sessions 1 and 3 and after session 5. Patient 1's THI decreased from 40 to 34 to 26; patient 4 reported a subjective improvement; patient 8 withdrew; and the remaining 5 patients reported no improvement. Side effects included temporary soreness, restlessness, and photophobia. The authors concluded that with these current parameters, rTMS did not improve tinnitus in veterans.
Kleinjung et al. (2008) stated that a growing number of studies demonstrate a reduction of tinnitus after repeated sessions of low-frequency rTMS and indicate that rTMS might represent a new promising approach for the treatment of tinnitus. Single sessions of high-frequency rTMS over the temporal cortex have been successful in reducing the intensity of tinnitus during the time of stimulation and could be predictive of treatment outcomes for chronic epidural stimulation using implanted electrodes. Because most available studies have been performed with small sample sizes and show only moderate effect sizes and high inter-individual variability of treatment effects, further development of the technique is needed before it can be recommended for use in clinical practice. Both patient-related (e.g., hearing loss, tinnitus duration, age) and stimulation-related (e.g., stimulation site, stimulation protocols) factors seem to influence treatment outcomes; however, their exact impact still remains to be clarified.
In a Cochrane review, Meng et al. (2011) evaluated the safety and effectiveness of rTMS versus placebo in patients with tinnitus. These investigators searched the Cochrane Ear, Nose, and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; ICTRP; and additional sources for published and unpublished trials. The date of the most recent search was May 24, 2011. Randomized controlled trials of rTMS versus sham rTMS were selected for this analysis. Two review authors reviewed the titles, abstracts, and keywords of all records retrieved; three review authors independently collected and extracted data and assessed the risk of bias of the trials. A total of 5 trials comprising 233 participants met inclusion criteria. Each study described the use of a different rTMS device that delivered different waveforms at different frequencies. All 5 trials were relatively small studies, but generally, they demonstrated a low risk of bias. When considering the impact of tinnitus on patients' quality of life, the results of only 1 study demonstrated a statistically significant improvement in THI scores at 4 months follow-up (defined as a "partial improvement" by the study authors (THI reduction of 21% to 80%)) when low-frequency rTMS was compared with a sham control treatment. However, no statistically significant improvement was demonstrated by another 2 studies that considered rTMS at the same frequency. Furthermore, this single positive finding should be taken in the context of the many different variables recorded at many different points in time by the study authors. In accordance with the authors' pre-specified subgroup analysis, they extracted the data from 1 study to consider the differential effectiveness between "lower" low-frequency rTMS (1 Hz) and "higher" low-frequency rTMS (10 Hz, 25 Hz). In doing this, they were able to demonstrate a statistically significant difference between rTMS employing a frequency of 1 Hz and the sham group when considering tinnitus severity and disability after 4 months follow-up ("partial" improvement). However, no statistically significant difference was demonstrated between 10 Hz and 25 Hz rTMS and the sham control group when considering the severity and disability of tinnitus at 4 months follow-up. When considering tinnitus loudness in patients undergoing rTMS, these investigators were able to demonstrate a statistically significant reduction in tinnitus loudness when the results of 2 studies were pooled (risk ratio 4.17, 95% confidence interval [CI]: 1.30 to 13.40). However, this finding was based on 2 small trials, and consequently, the confidence interval was particularly wide. No serious adverse effects were reported in any of the trials. The authors concluded that there is very limited support for the use of low-frequency rTMS for the treatment of patients with tinnitus. When considering the impact of tinnitus on patients' quality of life, support is derived from a single study with a low risk of bias based on a single outcome measure at a single point in time. When considering the impact on tinnitus loudness, this is based on the analysis of pooled data with a large confidence interval. Studies suggested that rTMS is a safe treatment for tinnitus in the short term; however, there were insufficient data to provide any support for the safety of this treatment in the long term. The authors stated that more prospective, randomized, placebo-controlled, double-blind studies with large sample sizes are needed to confirm the effectiveness of rTMS for tinnitus patients. Furthermore, uniform, validated, tinnitus-specific questionnaires as well as measurement scales should be used in future studies.
Plewnia et al. (2012) examined whether 4 weeks of bilateral rTMS to the temporal or temporo-parietal cortex is effective and safe in the treatment of chronic tinnitus. In this controlled 3-armed trial, a total of 48 patients with chronic tinnitus were treated with 4 weeks (20 sessions) of bilateral continuous theta burst stimulation (cTBS). They were randomized to stimulation above the temporal cortex, the temporo-parietal cortex, or as a sham condition behind the mastoid. Patients were masked for the stimulation condition. Tinnitus severity was assessed after 2 and primarily 4 weeks of treatment and at 3 months follow-up with the tinnitus questionnaire and by a tinnitus change score. Audiologic safety was monitored by pure-tone and speech audiometry after 2 and 4 weeks of cTBS. Tinnitus severity was slightly reduced from baseline by a mean (standard deviation [SD]) of 2.6 (8.2) after sham, 2.4 (8.0) after temporo-parietal, and 2.2 (8.3) after temporal treatment of 16 patients each, but there was no significant difference between sham treatments and temporal (CI: -5.4 to +6.7) or temporo-parietal cTBS (CI: -5.9 to +6.3) or real cTBS (CI: -7 to +5.1). Patients' global evaluation of tinnitus change after treatment did not indicate any effects. Audiologic measures were unaffected by treatment. The authors concluded that treating chronic tinnitus for 4 weeks by applying cTBS to the temporal or temporo-parietal cortex of both hemispheres appears to be safe but not more effective than sham stimulation.
In a review on "Repetitive transcranial magnetic stimulation as a treatment for chronic tinnitus," Theodoroff and Folmer (2013) concluded that "Although optimism for the clinical use of rTMS as an effective treatment for tinnitus remains high among many researchers, clinicians, and patients, several key questions and procedural issues remain unresolved. Suggestions for improving rTMS research protocols are described and discussed."
The American Academy of Otolaryngology - Head and Neck Surgery Foundation’s clinical practice guideline on "Tinnitus" (2014) stated that clinicians should not recommend transcranial magnetic stimulation (TMS) for the treatment of patients with persistent, bothersome tinnitus.
Sahlsten and colleagues (2019) stated that rTMS has shown variable effects on tinnitus. In a prospective, randomized, 6-month follow-up study on parallel groups, these researchers compared the effects of neuro-navigated rTMS to non-navigated rTMS in chronic tinnitus. A total of 40 patients (20 men, 20 women), with a mean age of 52.9 years (SD = 11.7), a mean tinnitus duration of 5.8 years (SD = 3.2), and a mean tinnitus intensity of 62.2/100 (SD = 12.8) on a visual analog scale (VAS) (0 to 100), participated. Subjects received 10 sessions of 1-Hz rTMS to the left temporal area overlying the auditory cortex, with or without neuro-navigation. The main outcome measures were VAS scores for tinnitus intensity, annoyance, and distress, and Tinnitus Handicap Inventory (THI) scores immediately and at 1, 3, and 6 months following treatment. The mean tinnitus intensity (hierarchical linear mixed model: F3 = 7.34, p = 0.0006), annoyance (F3 = 4.45, p = 0.0093), distress (F3 = 5.04, p = 0.0051), and THI scores (F4 = 17.30, p < 0.0001) decreased in both groups, with non-significant differences between the groups, except for tinnitus intensity (F3 = 2.96, p = 0.0451), favoring the non-navigated rTMS. Reduction in THI scores persisted for up to 6 months in both groups. Cohen's d for tinnitus intensity ranged between 0.33 and 0.47 in navigated rTMS and between 0.55 and 1.07 in non-navigated rTMS. The responder rates for VAS or THI ranged between 35% and 85%, with no differences between groups (p = 0.054 to 1.0). The authors concluded that rTMS was effective for chronic tinnitus, but the method of coil localization was not a critical factor for the treatment outcome. These researchers stated that more research on neuro-navigated rTMS for tinnitus is still needed to finally define the most optimal target site(s) and the coil orientation for the most successful tinnitus treatment.
This study had several drawbacks. It was a relatively small study (n = 40) with relatively short-term follow-up (6 months). Furthermore, there was no placebo group, so the outcomes may partly be due to a placebo effect. However, the authors noted that they had previously conducted a placebo-controlled randomized study on the topic with borderline results.
In a systematic review and meta-analysis, Liang and colleagues (2020) examined the safety and effectiveness of rTMS in the treatment of chronic tinnitus. Studies of rTMS for chronic tinnitus were retrieved from PubMed, Embase, and Cochrane Library through April 2020. Review Manager 5.3 software was employed for data synthesis, and Stata 13.0 software was used for analyses of publication bias and sensitivity. A total of 29 randomized studies involving 1,228 chronic tinnitus patients were included. Compared with sham rTMS, rTMS exhibited significant improvements in the THI scores at 1 week (mean difference [MD]: -7.92, 95% CI: -14.18 to -1.66), 1 month (MD: -8.52, 95% CI: -12.49 to -4.55), and 6 months (MD: -6.53, 95% CI: -11.406 to -1.66) post-intervention; there were significant mean changes in THI scores at 1 month (MD: -14.86, 95% CI: -21.42 to -8.29) and 6 months (MD: -16.37, 95% CI: -20.64 to -12.11) post-intervention, and the Tinnitus Questionnaire (TQ) score at 1 week post-intervention (MD: -8.54, 95% CI: -15.56 to -1.52). Non-significant efficacy of rTMS was found regarding the THI score 2 weeks post-intervention (MD: -1.51, 95% CI: -13.42 to -10.40); the mean change in TQ scores 1 month post-intervention (MD: -3.67, 95% CI: -8.56 to 1.22); TQ scores at 1 (MD: -8.97, 95% CI: -20.41 to 2.48) and 6 months (MD: -7.02, 95% CI: -18.18 to 4.13) post-intervention; and adverse events (AEs) (odds ratios [OR]: 1.11, 95% CI: 0.51 to 2.42). Egger's and Begg's tests indicated no publication bias (p = 0.925). The authors concluded that the findings of this meta-analysis demonstrated that rTMS was effective for chronic tinnitus; however, its safety needs more validation. These researchers stated that this analysis was restrained by the insufficient number of included studies and the small sample size; hence, large, randomized, double-blind, multi-center trials are needed for further verification.
Marder et al. (2022) noted that treatment approaches targeting both attentional/limbic and auditory systems may better alleviate tinnitus distress than approaches targeting the auditory system alone. In a case-series study, these investigators examined sequential prefrontal and temporo-parietal rTMS for the treatment of tinnitus with and without co-morbid depression. A total of 10 subjects with chronic tinnitus received sequential rTMS treatment involving excitatory stimulation administered to the left dorsolateral prefrontal cortex (DLPFC) or inhibitory stimulation administered to the right DLPFC, followed by inhibitory stimulation administered to the primary auditory cortex (Heschl's gyrus or HG). These investigators also carried out a systematic literature review to examine the existing literature on sequential rTMS treatment approaches for tinnitus. Results of the case series were interpreted in the context of tinnitus neurobiology and the extant literature. Subjects experienced a significant decrease (average of 21.7%) in symptoms on the Tinnitus Functional Index (TFI). Those with tinnitus alone experienced a greater mean symptom reduction than those with co-morbid major depressive disorder (MDD) (27.7% versus 17.0%, respectively). Adverse effects were transient and minor. The 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 to 12 weeks), while the addition of 20-Hz treatment at DLPFC appeared superior in the long term (90 to 180 days). The authors concluded that sequential rTMS approaches for the treatment of tinnitus, especially those administering low-frequency treatment at the left DLPFC, merit further investigation.
Transcranial Electrical Neuromodulation
- alternating current stimulation (tACS) and
- random noise stimulation (tRNS), both applied on the auditory cortex.
A database with 228 patients with chronic tinnitus who underwent non-invasive neuromodulation was retrospectively analyzed. The results of this study showed that a single session of tRNS induced a significant suppressive effect on tinnitus loudness and distress, in contrast to tACS. Multiple sessions of tRNS augmented the suppressive effect on tinnitus loudness but have no effect on tinnitus distress. The authors concluded that the findings of this preliminary study showed a possibly beneficial effect of tRNS on tinnitus and can be a motivation for future randomized placebo-controlled clinical studies with auditory tRNS for tinnitus. They stated that auditory alpha-modulated tACS does not seem to be contributing to the treatment of tinnitus.
Joos et al. (2015) noted that recently, transcranial random noise stimulation (tRNS) applied over the auditory cortex induced a more pronounced effect on tinnitus loudness than transcranial direct current stimulation (tDCS) and alternating current stimulation. These investigators performed tRNS over the temporo-parietal cortex in 154 patients with non-pulsatile tinnitus. A total of 119 patients received low-frequency tRNS (lf-tRNS), 19 received high-frequency tRNS (hf-tRNS), and 16 received whole frequency spectrum tRNS (wf-tRNS). The effect was evaluated using the numeric rating scale for loudness and distress pre- and post-stimulation. This study revealed a significant reduction in tinnitus loudness when lf-tRNS and hf-tRNS were applied, as well as a reduction in tinnitus-related distress with lf-tRNS. Moreover, these researchers observed a significantly more pronounced reduction in loudness and distress in pure tone (PT) tinnitus compared to narrow band noise (NBN) tinnitus when hf-tRNS was applied, a difference that could not be obtained with lf-tRNS. The authors concluded that based on these results, tRNS might be a promising treatment option for non-pulsatile tinnitus; however, they cannot yet provide a clear mechanistic explanation for the different results obtained with different types of stimulation, i.e., lf-tRNS, hf-tRNS, and wf-tRNS, or with different types of tinnitus, i.e., PT and NBN tinnitus.
In a systematic review and meta-analysis, Martins and colleagues (2022) examined the effectiveness of transcranial direct current stimulation (tDCS) on tinnitus distress, loudness, and psychiatric symptoms. These researchers carried out a systematic literature search of PubMed, Web of Science, Cochrane Library, VHL, Embase, PsycINFO, OVID, and CINAHL databases on articles published until July 2021. Inclusion criteria were published controlled trials using tDCS intervention with tinnitus patients, using a sham/control group, and measuring tinnitus loudness, distress, and/or psychiatric symptoms. A meta-analysis was conducted for the overall effect as well as to compare subgroups according to tDCS target (left temporoparietal area (LTA) and dorsolateral prefrontal cortex (DLPFC)). A total of 14 articles with 1,031 patients were included; 6 studies used tDCS over the DLPFC, 6 over the LTA, and 2 over both areas. Although the overall meta-analysis showed that tDCS significantly decreased tinnitus loudness (standardized mean difference [SMD] = -0.35; 95% CI: -0.62 to -0.08, p = 0.01) and distress (SMD = -0.50, 95% CI: -0.91 to -0.10, p = 0.02), the subgroup analysis showed a significant effect only for tDCS over LTA for loudness (SMD = -0.46, 95% CI: -0.80 to -0.12, p = 0.009), and no other area resulted in significant change. There was no significant effect of treatment on psychiatric symptoms. The authors concluded that tDCS may improve tinnitus loudness and distress with a small-to-moderate effect size. Moreover, these investigators stated that despite the overall positive effect, only LTA tDCS yielded a significant effect. They stated that further well-controlled studies with larger sample sizes and broader examination of tDCS montages and doses are needed.
Transmeatal Laser Irradiation
With transmeatal laser irradiation, a low-level laser is applied through the external acoustic meatus of the affected ear. The treatment takes place once a week for six minutes over a four-week period or more.
In a prospective, randomized, double-blinded, controlled study, Nakashima et al. (2002) assessed the effectiveness of 60-mW laser irradiation in the treatment of tinnitus. A total of 68 ears in 45 patients with disabling unilateral or bilateral tinnitus were included in this trial. The active or placebo laser treatment was administered transmeatally once a week for 6 minutes. Laser irradiation was performed four times during a 4-week period. A questionnaire was administered to evaluate the loudness, duration, quality, and annoyance of tinnitus before and after irradiation. The loudness and pitch match for tinnitus were obtained, and distortion product otoacoustic emissions were also examined. No significant difference was observed between the active and placebo laser groups with regard to the outcome of loudness, duration, quality, and annoyance of tinnitus. In one patient who received active laser treatment, acute hearing deterioration occurred after the third irradiation. These investigators concluded that transmeatal low-power laser irradiation with 60 mW is ineffective for the treatment of tinnitus.
Tauber et al. (2003) presented their findings from a feasibility study on the use of a laser application system in patients with chronic cochlear tinnitus and sensorineural hearing loss (n = 35). The laser TCL-system, consisting of 4 diode lasers (λ = 635 to 830 nm), was developed based on dosimetric data from a former light-dosimetric study. The chronic symptoms persisted after standard therapeutic procedures for at least 6 months, while retrocochlear or middle-ear pathologies had been ruled out. The patients were randomized and received 5 single-diode laser treatments (λ = 635 nm, 7.8 mW cw, n = 17, and λ = 830 nm, 20 mW cw, n = 18) with a space irradiation of 4 J/cm² at the site of maximal cochlear injury. For evaluation of laser-induced effects, complete otolaryngological examinations with audiometry, tinnitus masking and matching, and a tinnitus self-assessment were performed before, during, and after the laser irradiation. The first clinical use of the TCL-system was well-tolerated without side effects and produced no observable damage to the external, middle, or inner ear. Changes in tinnitus loudness and tinnitus matching were described. After a follow-up period of 6 months, tinnitus loudness was attenuated in 13 of 35 irradiated patients, while 2 of 35 patients reported their tinnitus as totally absent. Hearing threshold levels and middle ear function remained unchanged. These researchers stated that further investigations through large double-blind placebo-controlled studies are mandatory for the clinical evaluation of the presented TCL-system and its therapeutic effectiveness in acute and chronic cochlear dysfunction.
A systematic review of randomized controlled clinical trials of low-powered laser treatments for tinnitus found no statistically significant difference between laser and placebo (Meehan et al., 2004).
Gungor et al. (2008) assessed the effectiveness of laser irradiation in the treatment of chronic tinnitus. This study included 66 ears in 45 patients with chronic unilateral or bilateral tinnitus. A 5 mW laser with a wavelength of 650 nm, or a placebo laser, was applied transmeatally for 15 minutes, once daily for a week. A questionnaire was administered, which asked patients to score their symptoms on a 5-point scale before and 2 weeks after laser irradiation. A decrease of 1 scale point regarding the loudness, duration, and degree of annoyance of tinnitus was deemed an improvement. The loudness, duration, and degree of annoyance of tinnitus improved, respectively, in up to 48.8%, 57.7%, and 55.5% of the patients in the active laser group. No significant improvement was observed in the placebo laser group. The authors concluded that transmeatal, low-power (5 mW) laser irradiation was found to be useful for the treatment of chronic tinnitus. The findings of this study need to be validated by larger studies with longer follow-up.
Noble (2008) stated that the various forms of treatment for tinnitus that have been tested in properly controlled trials can be classified as pharmacological, acoustic-physical, and psychological. In clinical trials, no pharmacological agent has been shown to have a lasting effect on the presence or severity of tinnitus, although there are promising signs in an animal model. Acoustic devices do not seem to influence tinnitus, although appropriately fitted hearing aids may slightly reduce its prominence. Of physical treatments, cortical implantation may hold some promise of being effective for tinnitus suppression in selected cases. There was no mention of the use of laser.
- one group received active laser therapy 20 mins a day for 3 months with a 650-nm, 5-mW soft laser (group L), and
- the second group received a dummy device which duplicated all aspects of active laser therapy except for the activation of the laser beam (group C).
One subject in both groups dropped out due to an increase in tinnitus loudness. Two more patients in each group ceased to comply with the protocol due to familiar problems. The THI was considered the main outcome measure; no statistical difference was detected between the two groups in the THI total score (p = 0.97), and its functional (p = 0.89), emotional (p = 0.89) and catastrophic (p = 0.89) sub-scales. Moreover, a visual analog scale for self-perceived loudness of the tinnitus showed no difference between the groups (p = 0.69). Regarding psycho-acoustic parameters, the minimum masking level showed no difference (p = 0.42), while loudness expressed in sensation level exhibited lower values in group L (p = 0.0127). Group L subjects also presented a decreased rate of hyper-acusis (p = 0.02). No changes were detected in the audiometric threshold in both groups. The authors concluded that soft laser therapy demonstrated no efficacy as a therapeutic measure for tinnitus.
In a prospective, double-blinded, randomized, placebo-controlled trial, Ngao et al. (2014) examined the effectiveness of transmeatal low-power laser stimulation (TLLS) in treating tinnitus. Patients with persistent subjective tinnitus as their main symptom were recruited into the study from the out-patient clinics.
- the THI and
- visual analogue scale (VAS) symptoms rating scales, before starting the treatment and at the end of the 10-week treatment period.
The total score of the THI questionnaire was further graded into 5 grades, grade 1 being mild and grade 5 being catastrophic. Wilcoxon-signed ranks test and Mann-Whitney test were used to compare and analyze the THI and VAS scores before and after treatment for each group. Changes with p value of < 0.05 were considered as statistically significant. Chi-square test was used to analyze the change of parameters in categorical forms (to compare between TLLS+ and TLLS-). Changes with p value of < 0.05 were considered as statistically significant. A total of 43 patients successfully and diligently completed their treatment. It was noted that using any condition of the device, TLLS+ or TLLS-, patient's tinnitus symptoms improved in terms of THI scores (TLLS+, p value = 0.038; TLLS-, p value = 0.001) or VAS scores with a change of at least one grade (TLLS+, p value = 0.007; TLLS-, p value = 0.002) at p value <0.05 significant level. In contrast when TLLS+ group was compared with TLLS- group, no statistically significant result was obtained. In term of VAS scores, there seemed to be no statistically significant improvement in patients' annoyance, sleep disruption, depression, concentration and tinnitus loudness and pitch heard between the two groups. They stated that transmeatal low-power laser stimulation did not demonstrate significant efficacy as a therapeutic measure in treating tinnitus.
In a prospective, double-blind, placebo-controlled study, Dehkordi et al. (2015) examined the effect of low-dose laser therapy on chronic cochlear tinnitus. The study population was made up of 66 patients – 33 who received active laser treatment (case group) and 33 who received inactive dummy treatment (control group).
- the TSI,
- a subjective 10-point self-assessment scale for tinnitus loudness, and
- the Tinnitus Evaluation Test (TET).
At study's end, these researchers found no statistically significant differences between the case and control groups in the number of patients who experienced a reduction in TSI values (p = 0.589) or a reduction in subjective self-assessment scores (p = 0.475). In addition, these investigators did not find any significant reductions in the loudness (p = 0.665) and frequency (p = 0.396) of tinnitus as determined by the TET. The authors concluded that 5-mV laser therapy with a wavelength of 650 nm is no better than placebo for improving hearing thresholds overall or for treating tinnitus with regard to age, sex, environmental noise level, and the duration of tinnitus.
Vagal Nerve Stimulation
Schnupp (2011) stated that recent observations linking the vagus nerve to plasticity in the central nervous system could pave the way to new treatments for tinnitus, one of the most common and intractable disorders of the auditory system.
In a systematic review, Stegeman and colleagues (2021) examined the effect of vagus nerve stimulation (VNS) on distress and symptom severity in patients with chronic tinnitus. These investigators searched PubMed, Embase and the Cochrane Library systematically for RCTs, observational studies and case studies on the effect of VNS for the treatment of tinnitus on October 29, 2019. Studies including adult patients with subjective tinnitus, comparing transcutaneous or implantable VNS to placebo or no treatment or before and after application of VNS on tinnitus distress and tinnitus symptom severity measured with a validated questionnaire were eligible. The risk of bias was assessed with the appropriate tool for each type of study. The search identified 9 primary studies of which 2 were RCTs, 5 were cohort studies and 2 were case series or reports; 5 studies used transcutaneous VNS treatment and 4 used implanted VNS treatment; 6 studies combined VNS treatment with sound therapy. There was a serious risk of bias in all studies, especially on confounding. Most studies reported a small decrease in tinnitus distress or tinnitus symptom severity. The authors concluded that due to methodological limitations and low reporting quality of the included studies, the effect of VNS on tinnitus remains unclear. These researchers stated that to draw conclusions for which patient population and to what extent (t)VNS is beneficial in the treatment of tinnitus, a RCT should be considered.
Vitamin B12 Injections
In a randomized, double-blind, pilot study, Singh et al. (2016) examined the role of vitamin B12 in treatment of chronic tinnitus. A total 40 patients were enrolled, of which 20 in Group A (cases) received intramuscular therapy of 1 ml vitamin B12 (2,500 ug) weekly for a period of 6 weeks and Group B (20) patients received placebo isotonic saline intramuscular injection. Subjects were subjected to vitamin B12 assay and audiometry pre- and post-therapy. Of the total patients of tinnitus, 17 were vitamin B12 deficient (i.e., 42.5% showed deficiency when the normal levels were considered to be 250 pg/ml). A paired t-test showed that in Group A, patients with vitamin B12 deficiency showed significant improvement in mean tinnitus severity index score and VAS after vitamin B12 therapy. The authors concluded that the findings of this pilot study highlighted the significant prevalence of vitamin B12 deficiency in North Indian population; and improvement in tinnitus severity scores and VAS in cobalamin-deficient patients receiving intramuscular vitamin B12 weekly for 6 weeks further provided a link between cobalamin deficiency and tinnitus thereby is suggestive of a therapeutic role of vitamin B12 in cobalamin-deficient patients of tinnitus. These preliminary findings need to be validated by well-designed studies.
References
The above policy is based on the following references:
Auditory Perceptual Training
- Hoare DJ, Stacey PC, Hall DA. The efficacy of auditory perceptual training for tinnitus: A systematic review. Ann Behav Med. 2010;40(3):313-324.
Cognitive Behavioral Therapy (CBT)
- Chen K, Monaghan NP, Nguyen SA, et al. Outcomes of tinnitus interventions: An umbrella review of systematic reviews with meta-analysis. Ann Otol Rhinol Laryngol. 2026;135(5):342-355.
- Fuller T, Cima R, Langguth B, et al. Cognitive behavioural therapy for tinnitus. Cochrane Database Syst Rev. 2020;1(1):CD012614.
- Sherlock LP, Ballard-Hernandez J, Boudin-George A, et al. Clinical Practice Guideline for Management of Tinnitus: Recommendations from the US VA/DOD Clinical Practice Guideline Work Group. JAMA Otolaryngol Head Neck Surg. 2025;151(5):513-520.
- Woods JW, Theodoroff SM. Cognitive behavioral therapy for tinnitus. Audiol Today. 2019;31(6):22-28.
- Xian J, Zhang S, Xiao X, et al. Evidence synthesis of tinnitus treatment methods: An umbrella review. Am J Otolaryngol. 2025;46(5):104707.
Ear Canal Magnets and Electromagnetic Stimulation
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Deep Brain Stimulation
- Cheung SW, Larson PS. Tinnitus modulation by deep brain stimulation in locus of caudate neurons (area LC). Neuroscience. 2010;169(4):1768-1778.
- Shi Y, Burchiel KJ, Anderson VC, Martin WH. Deep brain stimulation effects in patients with tinnitus. Otolaryngol Head Neck Surg. 2009;141(2):285-287.
Hyperbaric Oxygen Therapy
- Bennett M, Kertesz T, Yeung P. Hyperbaric oxygen therapy for idiopathic sudden sensorineural hearing loss and tinnitus: A systematic review of randomized controlled trials. J Laryngol Otol. 2005;119(10):791-798.
- Bennett MH, Kertesz T, Yeung P. Hyperbaric oxygen for idiopathic sudden sensorineural hearing loss and tinnitus. Cochrane Database Syst Rev. 2007;(1):CD004739.
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- Savage J, Cook S, Waddell A. Tinnitus. In: BMJ Clinical Evidence. London, UK: BMJ Publishing Group; May 2009.
Intra-Cranial Venous Sinus Stenting
- Boddu S, Dinkin M, Suurna M, et al. Resolution of pulsatile tinnitus after venous sinus stenting in patients with idiopathic intracranial hypertension. PLoS One. 2016;11(10):e0164466.
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- Wang H, Stern JI, Robertson CE, Chiang C-C. Pulsatile tinnitus: Differential diagnosis and approach to management. Curr Pain Headache Rep. 2024;28(8):815-824.
Intra-Tympanic Administration of Corticosteroids
- Araujo MF, Oliveira CA, Bahmad FM Jr. Intratympanic dexamethasone injections as a treatment for severe, disabling tinnitus: Does it work? Arch Otolaryngol Head Neck Surg. 2005;131(2):113-117.
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- Dodson KM, Sismanis A. Intratympanic perfusion for the treatment of tinnitus. Otolaryngol Clin North Am. 2004;37(5):991-1000.
- Lee HJ, Kim MB, Yoo SY, et al. Clinical effect of intratympanic dexamethasone injection in acute unilateral tinnitus: A prospective, placebo-controlled, multicenter study. Laryngoscope. 2018;128(1):184-188.
- Phillips JS, Westerberg B. Intratympanic steroids for Ménière's disease or syndrome. Cochrane Database Syst Rev. 2011;(7):CD008514.
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- Topak M, Sahin-Yilmaz A, Ozdoganoglu T, et al. Intratympanic methylprednisolone injections for subjective tinnitus. J Laryngol Otol. 2009;123(11):1221-1225.
Miscellaneous Treatments
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- Bauer CA. Tinnitus. N Engl J Med. 2018;378(13):1224-1231.
- Berninger E, Nordmark J, Alvan G, et al. The effect of intravenously administered mexiletine on tinnitus - a pilot study. Int J Audiol. 2006;45(12):689-696.
- Blasco MA, Redleaf MI. Cochlear implantation in unilateral sudden deafness improves tinnitus and speech comprehension: Meta-analysis and systematic review. Otol Neurotol. 2014;35(8):1426-1432.
- Bolandi M, Javanbakht M, Shaabani M, Bakhshi E. Effectiveness of bimodal stimulation of the auditory-somatosensory system in the treatment of tonal tinnitus. Am J Otolaryngol. 2024;45(6):104449.
- Bulow M, Best N, Brugger S, et al. The effect of lidocaine iontophoresis for the treatment of tinnitus: A systematic review. Eur Arch Otorhinolaryngol. 2023;280(2):495-503.
- Chen K, Monaghan NP, Nguyen SA, et al. Outcomes of tinnitus interventions: An umbrella review of systematic reviews with meta-analysis. Ann Otol Rhinol Laryngol. 2026;135(5):342-355.
- Chen J, Jing R. The clinical efficacy of scalp acupuncture for tinnitus: A systematic review and meta-analysis. Complement Ther Med. 2025;88:103129.
- Chen M, Fan S, Mao J, et al. Reversing cochlear nucleus maladaptive plasticity via customized extracochlear stimulation: A new approach for tinnitus treatment. Adv Sci (Weinh). 2025;12(9):e2412349.
- Claes L, Stamberger H, Van de Heyning P, et al. Auditory cortex tACS and tRNS for tinnitus: Single versus multiple sessions. Neural Plast. 2014;2014:436713.
- Conlon B, Hamilton C, Hughes S, et al. Noninvasive bimodal neuromodulation for the treatment of tinnitus: Protocol for a second large-scale double-blind randomized clinical trial to optimize stimulation parameters. JMIR Res Protoc. 2019;8(9):e13176.
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- Conlon B, Langguth B, Hamilton C, et al. Bimodal neuromodulation combining sound and tongue stimulation reduces tinnitus symptoms in a large randomized clinical study. Sci Transl Med. 2020;12(564):eabb2830.
- D'Arcy S, Hamilton C, Hughes S, et al. Bi-modal stimulation in the treatment of tinnitus: A study protocol for an exploratory trial to optimise stimulation parameters and patient subtyping. BMJ Open. 2017;7(10):e018465.
- Dalrymple SN, Lewis SH, Philman S. Tinnitus: Diagnosis and management. Am Fam Physician. 2021;103(11):663-671.
- Dang J, Liu YCC. Treatment of objective tinnitus with transpalatal Botox® injection in a pediatric patient with middle ear myoclonus: A case report. Int J Pediatr Otorhinolaryngol. 2019;116:22-24.
- De Faria Gc NC, Gualberto Vc V, Bruzadelli SM, Bahmad F Jr. Efficacy of ozone therapy in the treatment of tinnitus: A systematic review. Int Tinnitus J. 2022;25(2):149-153.
- De Ridder D, Adhia D, Langguth B. Tinnitus and brain stimulation. Curr Top Behav Neurosci. 2021:51:249-293.
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- Dinces EA. Treatment of tinnitus. UpToDate [online serial]. Waltham, MA: UpToDate; reviewed March 2024.
- Ferrari G, Agnese A, Cavallero A, et al. Medical and surgical treatments for tinnitus: The efficacy of combined treatment with sulodexide and melatonin. J Neurosurg Sci. 2015;59(1):1-9.
- Ferreira MC, de Matos IL, de Toledo IP, et al. Effects of low-level laser therapy as a therapeutic strategy for patients with tinnitus: A systematic review. J Speech Lang Hear Res. 2021;64(1):279-298.
- Guillard R, Fraysse M-J, Simeon R, et al. A portable neurofeedback device for treating chronic subjective tinnitus: Feasibility and results of a pilot study. Prog Brain Res. 2021;260:167-185.
- Hahn A, Radkova L, Achiemere G, et al. Multimodal therapy for chronic tinnitus. Int Tinnitus J. 2008;14(1):69-72.
- Haller M, Hall DA. Evaluation of the acoustic Coordinated Reset (CR®) Neuromodulation therapy for tinnitus: Update on findings and conclusions. Front Psychol. 2017;8:1893.
- Hamilton C, D'Arcy S, Pearlmutter BA, et al. An investigation of feasibility and safety of bi-modal stimulation for the treatment of tinnitus: An open-label pilot study. Neuromodulation. 2016;19(8):832-837.
- He M, Li X, Liu Y, et al. Electroacupuncture for tinnitus: A systematic review. PLoS One. 2016;11(3):e0150600.
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- Kallio H, Niskanen ML, Havia M, et al. I.V. ropivacaine compared with lidocaine for the treatment of tinnitus. Br J Anaesth. 2008;101(2):261-265.
- Koning HM, Dyrbye BA, van Hemert FJ. Percutaneous radiofrequency lesion of the superior cervical sympathetic ganglion in patients with tinnitus. Pain Pract. 2016;16(8):994-1000.
- Koning HM, Meulen BCT. Pulsed radiofrequency of C2 dorsal root ganglion in patients with tinnitus. Int Tinnitus J. 2019;23(2):91-96.
- Larsen DG, Ovesen T. Tinnitus guidelines and treatment. Ugeskr Laeger. 2014;176(42).
- Laureano MR, Onishi ET, Bressan RA, et al. The effectiveness of acupuncture as a treatment for tinnitus: A randomized controlled trial using 99mTc-ECD SPECT. Eur Radiol. 2016;26(9):3234-42.
- Lee SY, Song SK, Park SJ, et al. Jugular bulb resurfacing with bone cement for patients with high dehiscent jugular bulb and ipsilateral pulsatile tinnitus. Otol Neurotol. 2019;40(2):192-199.
- Liu F, Han X, Li Y, Yu S. Acupuncture in the treatment of tinnitus: A systematic review and meta-analysis. Eur Arch Otorhinolaryngol. 2016;273(2):285-294.
- Liu H, Zhang J, Yang S, et al. Efficacy of sound therapy interventions for tinnitus management: A protocol for systematic review and network meta-analysis. Medicine (Baltimore). 2021;100(41):e27509.
- Luyten T, Van de Heyning P, Jacquemin L, et al. The value of eye movement desensitization reprocessing in the treatment of tinnitus: Study protocol for a randomized controlled trial. Trials. 2019 20(1):32.
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- Mahboubi H, Ziai K, Djalilian HR. Customized web-based sound therapy for tinnitus. Int Tinnitus J. 2012b;17(1):26-30.
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- Raghavan P, Serulle Y, Gandhi D, et al. Postoperative imaging findings following sigmoid sinus wall reconstruction for pulse synchronous tinnitus. AJNR Am J Neuroradiol. 2016;37(1):136-142.
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- Santa Maria PL. Sigmoid sinus dehiscence resurfacing as treatment for pulsatile tinnitus. J Laryngol Otol. 2013;127 Suppl 2:S57-S59.
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- Sereda M, Xia J, El Refaie A, et al. Sound therapy (using amplification devices and/or sound generators) for tinnitus. Cochrane Database Syst Rev. 2018;12:CD013094.
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- Talluri S, Palaparthi SM, Michelogiannakis D, Khan J. Efficacy of photobiomodulation in the management of tinnitus: A systematic review of randomized control trials. Eur Ann Otorhinolaryngol Head Neck Dis. 2022;139(2):83-90.
- Tao DD, Chen B. Effects of cochlear implantation on ipsilateral tinnitus. Zhonghua Yi Xue Za Zhi. 2012;92(25):1756-1758.
- Tavora-Vieira D, Marino R, Krishnaswamy J, et al. Cochlear implantation for unilateral deafness with and without tinnitus: A case series. Laryngoscope. 2013;123(5):1251-1255.
- Theodoroff SM, McMillan GP, Zaugg TL, et al. Randomized controlled trial of a novel device for tinnitus sound therapy during sleep. Am J Audiol. 2017;26(4):543-554.
- Tian S, Wang L, Yang J, et al. Sigmoid sinus cortical plate dehiscence induces pulsatile tinnitus through amplifying sigmoid sinus venous sound. J Biomech. 2017;52:68-73.
- Tunkel DE, Bauer CA, Sun GH, et al. Clinical practice guideline: Tinnitus. Otolaryngol Head Neck Surg. 2014;151(2 Suppl):S1-S40.
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- Vielsmeier V, Schecklmann M, Schlee W, et al. A pilot study of peripheral muscle magnetic stimulation as add-on treatment to repetitive transcranial magnetic stimulation in chronic tinnitus. Front Neurosci. 2018;12:68.
- Vlastarakos PV, Nazos K, Tavoulari EF, Nikolopoulos TP. Cochlear implantation for single-sided deafness: The outcomes. An evidence-based approach. Eur Arch Otorhinolaryngol. 2014;271(8):2119-2126.
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- Wegger M, Ovesen T, Larsen DG. Acoustic coordinated reset neuromodulation: A systematic review of a novel therapy for tinnitus. Front Neurol. 2017;8:36.
- Yakunina N, Kim SS, Nam EC. BOLD fMRI effects of transcutaneous vagus nerve stimulation in patients with chronic tinnitus. PLoS One. 2018;13(11):e0207281.
- Yeo WX, Xu SH, Tan TY, et al. Surgical management of pulsatile tinnitus secondary to jugular bulb or sigmoid sinus diverticulum with review of literature. Am J Otolaryngol. 2018;39(2):247-252.
- Zeng R, Wang G-P, Liu Z-H, et al. Sigmoid sinus wall reconstruction for pulsatile tinnitus caused by sigmoid sinus wall dehiscence: A single-center experience. PLoS One. 2016;11(10):e0164728.
- Zenner HP, Delb W, Kröner-Herwig B, et al. A multidisciplinary systematic review of the treatment for chronic idiopathic tinnitus. Eur Arch Otorhinolaryngol. 2017;274(5):2079-2091.
- Zenner HP, Delb W, Kroner-Herwig B, et al. On the interdisciplinary S3 guidelines for the treatment of chronic idiopathic tinnitus. HNO. 2015;63(6):419-427.
Neuromonics Tinnitus Treatment
- Davis PB, Paki B, Hanley PJ. Neuromonics Tinnitus Treatment: Third clinical trial. Ear Hear. 2007;28(2):242-259.
- Davis PB, Wilde RA, Steed LG, Hanley PJ. Treatment of tinnitus with a customized acoustic neural stimulus: A controlled clinical study. Ear Nose Throat J. 2008;87(6):330-339.
- Hanley PJ, Davis PB. Treatment of tinnitus with a customized, dynamic acoustic neural stimulus: Underlying principles and clinical efficacy. Trends Amplif. 2008;12(3):210-222.
Sequential Phase Shift Sound Cancellation Treatment
- Choy DSJ, Kaminow I. A novel treatment of predominant tone tinnitus with sequential sound cancellation [abstract]. Presented at the VIIIth International Tinnitus Seminar, Pau, France, September 2005. Available at: http://tinnitusphase-out.com/research.html. Accessed May 7, 2007.
- Heijneman KM, de Kleine E, van Dijk P. A randomized double-blind crossover study of phase-shift sound therapy for tinnitus. Otolaryngol Head Neck Surg. 2012;147(2):308-315.
- Lipman RI, Lipman SP, Steehler KW. Phase shift treatment for predominant tone tinnitus [abstract]. Presented at the 90th Annual Clinical Assembly of the American Osteopathic College of Ophthalmology and Otolaryngology - Head and Neck Surgery, Orlando, FL, May 3-7, 2006. Available at: http://tinnitusphase-out.com/research.html. Accessed May 7, 2007.
- Lipman RI, Lipman SP. Phase-shift treatment for predominant tone tinnitus. Otolaryngol Head Neck Surg. 2007;136(5):763-768.
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Tinnitus Instruments (Maskers, Hearing Aids)
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Tinnitus Retraining Therapy
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- Dobie RA. A review of randomized clinical trials in tinnitus. Laryngoscope. 1999;109(8):1202-1211.
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Transcranial Magnetic Stimulation
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- Kleinjung T, Eichhammer P, Langguth B, et al. Long-term effects of repetitive transcranial magnetic stimulation (rTMS) in patients with chronic tinnitus. Otolaryngol Head Neck Surg. 2005;132(4):566-569.
- Kleinjung T, Vielsmeier V, Landgrebe M, et al. Transcranial magnetic stimulation: A new diagnostic and therapeutic tool for tinnitus patients. Int Tinnitus J. 2008;14(2):112-118.
- Lee SL, Abraham M, Cacace AT, Silver SM. Repetitive transcranial magnetic stimulation in veterans with debilitating tinnitus: A pilot study. Otolaryngol Head Neck Surg. 2008;138(3):398-399.
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Transcutaneous Electrical Nerve Stimulation (TENS) for Tinnitus
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Transmeatal Laser Irradiation
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Vagal Nerve Stimulation
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