Investigation of the Effectiveness of Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) and Vestibular Rehabilitation in Patients with Unilateral Vestibular Hypofunction

Background: Vagus nerve stimulation (VNS) is a frequently used neuromodulation method in recent years. While the mechanism of improvement in diseases such as epilepsy, dementia, and depression is being studied, its potential effect on vestibular dysfunction is also being investigated. The aim of our study was to investigate the effect of transcutaneous auricular VNS (taVNS) on the vestibular symptoms of unilateral vestibular hypofunction (UVH). Methods: Forty patients diagnosed with UVH were randomly divided into two groups. Group 1 received vestibular rehabilitation. Group 2 received taVNS and vestibular rehabilitation. Both groups received treatment one day a week for eight weeks. Before and after the treatment, balance of the participants was assessed with modified-CTSIB (m-CTSIB), limit of stability (LOS), Tandem and One-Leg Stance (OLS) tests; visual acuity was assessed with dynamic visual acuity (DVA), dizziness severity, and fatigue severity with a visual analog scale (VAS); kinesiophobia was assessed with the Tampa Scale for Kinesiophobia (TSK); depression and anxiety was assessed with the Hospital Anxiety and Depression Scale (HADS); and quality of life was assessed with the Dizziness Handicap Inventory (DHI). Results: At the end of eight weeks, patients in Group 2 showed significantly greater improvement in balance, dizziness, fatigue, kinesiophobia, anxiety, and depression. There was no significant difference in visual acuity and quality of life between the groups. Conclusions: The positive effects of taVNS on vestibular symptoms have been observed. As a new approach, taVNS can be included in the treatment of patients with UVH in addition to vestibular rehabilitation.