Somatosensorischer Tinnitus

[Somatosensory tinnitus]

BACKGROUND

Somatosensory tinnitus represents a clinically significant subgroup of chronic tinnitus. Although not completely understood, increasing evidence suggests interactivity between the somatosensory and auditory systems is responsible for both the development and maintenance of tinnitus.

OBJECTIVES

The aim of this study is to provide an overview of the evaluation of somatosensory tinnitus and to propose an examination protocol to support the diagnosis and treatment of this patient group.

MATERIALS AND METHODS

In addition to patient history, various clinical examination maneuvers are presented to establish the diagnosis of somatosensory tinnitus.

RESULTS

The maneuvers can be divided into examinations of the cervical spine, temporomandibular joint, and soft tissue near the jaw. The maneuvers should be performed in a quiet environment and usually in comparison between sides.

CONCLUSION

Accurate and efficient diagnosis of somatosensory tinnitus is essential to initiate appropriate treatment. The clinical maneuvers presented here are well suited for this purpose.

Somatosensory Tinnitus: Recent Developments in Diagnosis and Treatment

Somatosensory tinnitus (ST) is a type of tinnitus where changes in somatosensory input from the head-neck area are one of the influencing factors of a patient's tinnitus. As there are often several influencing factors, identifying a clear somatosensory influence on an individual patient's tinnitus is often a challenge. Therefore, a decision tree using four clinical criteria has been proposed that can help diagnose ST with an accuracy of 82.2%, a sensitivity of 82.5%, and a specificity of 79%. Once correctly diagnosed, patients can be successfully treated using a musculoskeletal physical therapy treatment. This type of treatment can either be directed at cervical spine dysfunctions, temporomandibular disorders, or both and consists of a combination of counseling, exercises, and manual techniques to restore normal function of the cervical spine and temporomandibular area. Other techniques have been suggested but need further investigation in larger RCTs. In most cases, ST treatment shows a decrease in tinnitus severity or loudness, but in rare cases, total remission of the tinnitus is achieved.

[Pilot study: evaluation of manual methods for modulating the cardinal symptom tinnitus : A prospective randomized study]

Hintergrund

Tinnitus und Schwindel wurden schon auf vielfältige Weise untersucht. Daraus ergaben sich multiple Erklärungsansätze aus verschiedenen medizinischen Disziplinen. Auch die Muskulatur des Kiefers und der Halswirbelsäule wurde diesbezüglich erforscht. Es zeigten sich deutliche Hinweise dafür, dass bei Funktionsstörungen dieser Muskulatur Tinnitus ausgelöst werden kann. Diese Unterart des Tinnitus wird als sog. zervikogener somatosensorischer Tinnitus bezeichnet.

Ziel der Studie

Das Ziel war die Untersuchung des Effekts der manuellen Therapie auf die von Probanden berichtete, individuell empfundene Beeinträchtigung durch zervikogenen somatosensorischen Tinnitus (Tinnitus Handicap Inventory), auf die Schwindelsymptomatik (Dizziness Handicap Inventory) und auf die hypertone zervikokraniale Muskulatur.

Methodik

In einer prospektiven randomisierten Studie wurden 80 Patient*innen (40 in der Interventionsgruppe und 40 in der Kontrollgruppe) ärztlich untersucht und befragt. Anschließend erhielten sie manuelle Therapie.

Ergebnisse

Nach manueller Therapie zeigten sich bzgl. des Tinnitus Handicap Inventory, des Dizziness Handicap Inventory und muskulärer Hypertonien signifikante Unterschiede zwischen den Gruppen zugunsten der Interventionsgruppe.

Schlussfolgerung

Die manuelle Untersuchung und Therapie stellten sich als wirksam heraus. Sie sollte bei ausbleibender HNO-ärztlicher Organpathologie und Verdacht auf zervikogenen somatosensorischen Tinnitus verstärkt zur Anwendung kommen. Die Rolle der einzelnen Muskeln gilt es tiefergehend zu untersuchen.

Somatosensory Tinnitus Diagnosis: Diagnostic Value of Existing Criteria

BACKGROUND

Tinnitus can be influenced by changes in somatosensory afference from the cervical spine or temporomandibular area, then called somatosensory or somatic tinnitus (ST). In 2018, a new set of diagnostic criteria for ST was agreed upon by a large group of ST experts. Currently, however, it still requires extensive and specific expertise to diagnose ST correctly. The next step in the development of easily applicable diagnostic criteria is to assess the diagnostic value of each individual criterion.

OBJECTIVES

The aim of this study was, therefore, to further investigate the diagnostic value of these criteria, validate them empirically, and identify their sensitivity and specificity.

METHODS

An online survey, questioning the presence of 12 diagnostic criteria for ST in a convenience sample of participants with tinnitus, was launched on the online forum Tinnitus Talk, managed by Tinnitus Hub. Participants were divided into three groups: a group with no somatic influence, a group with some somatic influence and a group with large somatic influence on their tinnitus. Chi-square tests were used to calculate differences between these groups. Afterward, sensitivity, specificity, positive and negative likelihood ratios (LR), and pre- and posttest probabilities were calculated for each ST diagnostic criterion. For this analysis, all patients with some and large somatic influence were compared as one group to the group with no somatic influence.

RESULTS

In total, 8221 participants filled out the online survey. As expected, the diagnostic criteria for ST are more prevalent in the groups with somatic influence, but the criterium of tinnitus modulation also often occurs in the group with no somatic influence. The simultaneous onset or increase and decrease of both tinnitus and pain complaints have the highest positive LR (6.29 and 10.72, respectively), next to the influence of certain postures on the tinnitus (+LR: 6.04). To rule out ST, the absence of neck pain or tension in the neck extensor muscles are most suited, as they decrease the posttest probability to 18% and 19%, respectively.

CONCLUSION

The simultaneous onset or increase and decrease of tinnitus and neck or jaw pain and the influence of certain postures are most suited to use as a single criterion for identifying patients with a somatic influence on their tinnitus. On the other hand, the absence of neck pain or tension in the neck extensor muscles is valid criterion to rule out a somatic influence. Additional analysis is needed to identify clusters of symptoms and criteria to further aid ST diagnosis.

Lidocaine injections to the otic ganglion for the treatment of tinnitus-A pilot study

Tinnitus is defined as the perception of noise without an external acoustic stimulus. Due to the heterogeneity of tinnitus, no treatment has proven equally beneficial to every single of these patients. Previous studies have shown that trigeminal input can interfere with the perception of tinnitus. Therefore, we aimed to explore the therapeutic potential of lidocaine injections in trigeminal structures. We conducted a pilot study with 19 participants to explore feasibility and tolerability of this approach. The intervention consisted of three injections of lidocaine in the anatomical area of the trigeminal ganglion and the ganglion oticum via an oral approach corresponding to the affected side of tinnitus. We performed an assessment that included the Mini-TQ, CGII, and numeric rating scales of tinnitus loudness and severity at different time points over a follow-up period of 12 weeks. In addition to changes of subjective tinnitus complaints, potential adverse events were documented. Patients were treated at the Centre of Otorhinolaryngology in Traunstein, Germany, and data were analyzed at the University of Regensburg, Germany. We did not observe any relevant side effects. There was a significant reduction of tinnitus distress (Mini-TQ, Tinnitus severity) and loudness (measured subjectively) over time. Our pilot data suggests that lidocaine injections targeting trigeminal structures may be able to reduce tinnitus complaints. Future studies should investigate the effects of lidocaine injections in placebo-controlled trials in an extended sample size to further explore the potential benefits of this therapeutic approach on tinnitus.

Diagnostic Criteria for Somatosensory Tinnitus: A Delphi Process and Face-to-Face Meeting to Establish Consensus

Since somatic or somatosensory tinnitus (ST) was first described as a subtype of subjective tinnitus, where altered somatosensory afference from the cervical spine or temporomandibular area causes or changes a patient’s tinnitus perception, several studies in humans and animals have provided a neurophysiological explanation for this type of tinnitus. Due to a lack of unambiguous clinical tests, many authors and clinicians use their own criteria for diagnosing ST. This resulted in large differences in prevalence figures in different studies and limits the comparison of clinical trials on ST treatment. This study aimed to reach an international consensus on diagnostic criteria for ST among experts, scientists and clinicians using a Delphi survey and face-to-face consensus meeting strategy. Following recommended procedures to gain expert consensus, a two-round Delphi survey was delivered online, followed by an in-person consensus meeting. Experts agreed upon a set of criteria that strongly suggest ST. These criteria comprise items on somatosensory modulation, specific tinnitus characteristics, and symptoms that can accompany the tinnitus. None of these criteria have to be present in every single patient with ST, but in case they are present, they strongly suggest the presence of ST. Because of the international nature of the survey, we expect these criteria to gain wide acceptance in the research field and to serve as a guideline for clinicians across all disciplines. Criteria developed in this consensus paper should now allow further investigation of the extent of somatosensory influence in individual tinnitus patients and tinnitus populations.