Alterations in Auditory Electrophysiological Responses Associated With Temporary Suppression of Tinnitus Induced by Low-Level Laser Therapy: A Before-After Case Series

Abstract

IntroductionTinnitus is the phantom auditory perception of sound in the absence of an external or internal acoustic stimulus.1 This symptom is a debilitating condition that is widespread yet difficult to successfully diagnose and treat. The prevalence of chronic tinnitus in general population is estimated between 5%-15%. It causes serious psychosocial complications in 1% to 3%.2 For some subjects, tinnitus is disabling and restricts their work, sleep, and social activities. [3][4][5] This symptom has forced clinicians to attempt to establish protocols for accuracy of tinnitus diagnosis and treatment. 6 There are various modalities in the treatment of the chronic tinnitus (pharmacotherapy, physiotherapy, psychotherapy, surgery etc) targeted at diminishing tinnitus loudness and annoyance. The disappearance of tinnitus occurs very rarely among the subjects with chronic tinnitus and according to the literature they do not represent a statistically significant group. The new medical therapeutic method of low-level laser therapy (LLLT) uses low-energy-lasers or light-emitting diodes to stimulate or inhibit cellular function.7 Lowlevel laser (LLL) is widely used by specialists to treat non-healing ulcers, autoimmune diseases, acute and chronic musculoskeletal pains, chronic inflammations, hemangiomas and burns. It has been suggested to be Abstract Introduction: Tinnitus is the phantom auditory perception of sound in the absence of an external or internal acoustic stimulus. The treatment is difficult due to multiple etiologies and great psychological influence. The purpose of this study was to determine alterations in auditory physiological and electrophysiological responses associated with temporary suppression of tinnitus induced by low-level laser (LLL) irradiation. Methods: This study was conducted on 20 subjects with subjective tinnitus. All subjects signed the informed consent form and satisfied all the study eligibility criteria. 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-low level laser therapy (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 infra-red (808 nm) were applied, and were both designed by the Canadian Optic and Laser (COL) Center. Twelve sessions of laser therapy were performed, 2 sessions per week for each subject. Total dose was 120 Joule/ ear/session. Results: LLL irradiation could cause a significant decrease in subjective tests scores consisting of VAS for loudness, PMT, P-TQ, P-THI, but did not result in a significant improvement of objective evaluating parameters except for compound action potential (CAP) amplitude. Conclusion: LLLT might be a subjectively effective treatment for short-term improvement of tinnitus. Defining a new protocol for optimizing LLLT paramete...

Effectiveness of Dry Needling in Bothersome Chronic Tinnitus in Patients with Myofascial Trigger Points

“…In a clinical trial, 20 patients with subjective tinnitus underwent 2 weekly sessions, up to a total of 12 complete sessions with continuous, low-intensity, red-wave (630 nm) and infrared (808 nm) diode laser, full dose of 120 Joules per ear and per session with the purpose of suppressing tinnitus temporarily. 46 A paired t-test showed improvement in the VAS for tinnitus intensity from 5.7 before to 3.2 after completing therapy ( p <0.0001); the THI score reduced from 68.6 to 54.6 (14 points reduction on average).…”

Objective Detection of Tinnitus Based on Electrophysiology

“…CAP amplitudes were suppressed and thresholds increased in tinnitus patients induced by sodium salicylate in one study [ 180 ]. Improvement of CAP amplitude after low-level laser treatment in tinnitus subjects was shown in one study, which may indicate the reduction in neural network activity in the presence of tinnitus [ 181 ]. AP latency was prolonged significantly along with the amplitude of AP tending to reduction without significant difference in cases with tinnitus reduced after injection of lidocaine [ 182 ].…”

“…Moreover, some indirect evidence, such as EcochG can be used to detect synaptopathy, and synaptopathy can cause tinnitus [ 32 , 177 ]. After some time of treatment, tinnitus is relieved and the electrocochleogram is also changed [ 179 , 181 , 182 ]. These pieces of evidence show that electrocochleogram has the potential to detect tinnitus, but more in-depth research needs to be carried out in the future.…”

O uso do laser de baixa intensidade em indivíduos com zumbido e sem perda auditiva

“…Existem várias modalidades para o tratamento do zumbido, com destaque para a terapia farmacêutica, fisioterapia, psicoterapia, cirurgia, entre outros. Todos visam diminuir a intensidade e o aborrecimento que o zumbido causa ao indivíduo (MONTAZERI et al, 2017). No entanto, uma vez que sua fisiopatologia não foi bem definida, não há um tratamento comprovadamente eficaz para solucionar o problema.…”