Combining Vestibular Rehabilitation and Noisy Galvanic Vestibular Stimulation for Treatment of Unilateral Vestibulopathy: A Randomized Controlled Trial

Abstract

Background and Aim: Vestibular Rehabilitation (VR) is a well-accepted treatment for Unilateral Vestibulopathy (UVP). Since noisy Galvanic Vestibular Stimulation (nGVS) improves the processing of vestibular inputs, we assessed the synergistic effects of adding nGVS to vestibular rehabilitation for the treatment of UVP. Methods: Patients with UVP were randomly assigned into two groups receiving either VR for four weeks (VR group, n=12) or VR for four weeks combined with nGVS for three sessions (VR+nGVS group; n=12). Outcome measurements were postural control parameters measured with eyes open/closed conditions on hard/soft surfaces, Vestibulo-Ocular Reflex (VOR) gain, and Dizziness Handicap Inventory (DHI) scores that were assessed at baseline and after four weeks. Results: All postural control parameters,  mean  total  and  subscale  scores  of  DHI,  and  mean VOR gain in directions of affected canals significantly improved in both groups after interventions (p<0.05) except mean mediolateral displacement in conditions with eyes closed on hard surface and with eyes open on soft surface, mean mediolateral velocity in conditions with eyes closed on hard surface, ability to stance with eye closed condition on soft surface   and mean emotional subscale of DHI in VR group. Improvements were significantly higher     in postural control outcomes measured in stances with eyes closed on hard surface and with eyes open and closed on soft surface, mean VOR gains in directions of affected horizontal and anterior canals, and mean total, physical, and functional scores of DHI in VR+nGVS group (p<0.05). Conclusion: When combined with VR, nGVS shows additional therapeutic effects in UVP patients. Keywords: Unilateral peripheral vestibulopathy; vestibular compensation; galvanic vestibular stimulation; vestibular rehabilitation; postural control