Combined Percutaneous Auricular Vagus Nerve Stimulation, Cervical Transcutaneous Electric Stimulation, and Transmeatal Photobiomodulation for Tinnitus: A Retrospective Quasi-Experimental Study of 120 Outpatients

Objective: to assess the combined effects of aVNS, TENS, and transmeatal photobiomodulation on tinnitus perception and discomfort. Methods: This was a retrospective quasi-experimental study using medical records of 120 patients with chronic somatosensory tinnitus treated at a specialized health center. Interventions included auricular vagus nerve stimulation (aVNS), cervical transcutaneous electrical nerve stimulation (TENS), and transmeatal photobiomodulation with laser. The Visual Analogue Scale (VAS) scores for tinnitus loudness and discomfort and Tinnitus Handicap Inventory (THI) scores were assessed pre- and post-intervention. Results: Non-parametric and frequency tests were used to compare outcomes, and effect sizes (ES) were calculated. Significant reductions were observed in VAS loudness (p = 0.001; ES = 2.01) and discomfort (p = 0.001; ES = 2.23), as well as THI scores (p = 0.001; ES = 2.28). The severity classifications of tinnitus, based on VAS and THI scores, also improved significantly. The effect sizes were very large for all variables, suggesting a synergistic beneficial effect from combined interventions. Conclusions: The combination of aVNS, TENS, and transmeatal photobiomodulation seems to be an effective therapeutic strategy for reducing tinnitus perception, discomfort, and self-perceived handicap. While these findings highlight the potential of this multimodal approach, further randomized controlled trials are necessary to confirm its efficacy and elucidate the underlying mechanisms.