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

Intratympanic Lidocaine as a Potent Remedy for Tinnitus in Sudden Sensorineural Hearing Loss: A Double-Blind, Randomized Clinical Trial

OBJECTIVE

This study evaluates intratympanic lidocaine's efficacy and safety for tinnitus relief in sudden sensorineural hearing loss (SSNHL) patients.

METHODS

In a double-blind randomized controlled trial, 100 SSNHL patients with unilateral tinnitus received either intratympanic lidocaine or saline plus usual care. Treatment impact was assessed at 1 and 3 months using the Tinnitus Handicap Inventory, subjective visual analog scale, pure-tone audiometry.

RESULTS

The lidocaine group demonstrated significant tinnitus relief according to the Tinnitus Handicap Inventory and visual analog scale, without pure-tone audiometry improvement or serious adverse events throughout the study period.

CONCLUSION

Intratympanic lidocaine provides a safe, efficacious treatment option for SSNHL tinnitus. Further studies should refine the dosage and delivery parameters because of SSNHL's heterogenous nature.

Tinnitus Guidelines and Their Evidence Base

Evidence-based medicine (EBM) is generally accepted as the gold standard for high-quality medicine and, thus, for managing patients with tinnitus. EBM integrates the best available scientific information with clinical experience and patient values to guide decision-making about clinical management. To help health care providers and clinicians, the available evidence is commonly translated into medical or clinical guidelines based on a consensus. These involve a systematic review of the literature and meta-analytic aggregation of research findings followed by the formulation of clinical recommendations. However, this approach also has limitations, which include a lack of consideration of individual patient characteristics, the susceptibility of guideline recommendations to material and immaterial conflicts of interest of guideline authors and long latencies till new knowledge is implemented in guidelines. A further important aspect in interpreting the existing literature is that the absence of evidence is not evidence of absence. These circumstances could result in the decoupling of recommendations and their supporting evidence, which becomes evident when guidelines from different countries differ in their recommendations. This opinion paper will discuss how these weaknesses can be addressed in tinnitus.

Too Blind to See the Elephant? Why Neuroscientists Ought to Be Interested in Tinnitus

A curative therapy for tinnitus currently does not exist. One may actually exist but cannot currently be causally linked to tinnitus due to the lack of consistency of concepts about the neural correlate of tinnitus. Depending on predictions, these concepts would require either a suppression or enhancement of brain activity or an increase in inhibition or disinhibition. Although procedures with a potential to silence tinnitus may exist, the lack of rationale for their curative success hampers an optimization of therapeutic protocols. We discuss here six candidate contributors to tinnitus that have been suggested by a variety of scientific experts in the field and that were addressed in a virtual panel discussion at the ARO round table in February 2021. In this discussion, several potential tinnitus contributors were considered: (i) inhibitory circuits, (ii) attention, (iii) stress, (iv) unidentified sub-entities, (v) maladaptive information transmission, and (vi) minor cochlear deafferentation. Finally, (vii) some potential therapeutic approaches were discussed. The results of this discussion is reflected here in view of potential blind spots that may still remain and that have been ignored in most tinnitus literature. We strongly suggest to consider the high impact of connecting the controversial findings to unravel the whole complexity of the tinnitus phenomenon; an essential prerequisite for establishing suitable therapeutic approaches.