Balance in Virtual Reality: Effect of Age and Bilateral Vestibular Loss

Abstract

BackgroundQuantitative balance measurement is used in clinical practice to prevent falls. The conditions of the test were limited to eyes open, eyes closed, and sway-referenced vision. We developed a new visual perturbation to challenge balance using virtual reality (VR), measuring postural stability by a Wii Balance Board (WBB).MethodsIn this study, we recorded balance performance of 116 healthy subjects and of 10 bilateral vestibular loss patients using VR to assess the effect of age and the effect of total loss of vestibular function. We used several conditions: eyes open (normal visual inputs), eyes closed (no visual inputs), stable visual world (vision referenced), and perturbed visual world (visual perturbation) at different amplitudes of perturbation. Balance under these visual conditions was assessed on the WBB (stable support surface) and on the WBB plus foam rubber (unstable support surface).ResultsIn healthy subjects, we found that the percentage of falls increased with age and with the amplitude of perturbation for both conditions: WBB or WBB + foam. Moreover, we can define a threshold for falls in each age group as the amplitude of perturbation which induced falls. For bilateral vestibular loss patients, on the WBB + foam, all of them failed with eyes closed and with perturbed visual world even at the minimal amplitude of perturbation. Finally, we observed that stable visual world induced fewer falls than eyes closed whatever the subject’s group (healthy or bilateral vestibular loss) and whatever the age decade.ConclusionVR allowed us to develop a useful new tool with a wide range of visual perturbations. Rather than only two levels of visual condition (eyes open and eyes closed), the VR stimulus can be continuously adjusted to produce a visual perturbation powerful enough to induce falls even in young healthy subjects and which has allowed us to determine a threshold for falls.

A Novel Saccadic Strategy Revealed by Suppression Head Impulse Testing of Patients with Bilateral Vestibular Loss

“…The inclusion criteria were that they demonstrated the following symptoms: postural imbalance, unsteadiness of gait, movement-induced blurred vision (oscillopsia) during walking or most quick head/body movement, and worsening of postural imbalance or unsteadiness of gait in darkness and/or on uneven ground ( 20 ). To establish their loss of vestibular function we measured: (1) horizontal semicircular canal function by the video HIMPs, the suppression head impulse paradigm (SHIMPs), the caloric test; (2) otolith function by cervical and ocular vestibular-evoked myogenic potentials (VEMPs) ( 21 , 22 ); (3) postural stability by the EquiTest, and the Nintendo Wii balance Board (WBB) ( 23 ).…”

“…All eight patients had absent cervical vestibular-evoked myogenic potentials (cVEMPs): no detectable p13-n23 cervical potentials and no detectable ocular vestibular-evoked myogenic potentials (oVEMPs): no n1-p1 ocular potentials were detected on either side in response to short tone bursts of air-conducted sound at 500 Hz at 102 dB SPL ( 24 ). All of them fell on condition 5 in Equitest and were unable to maintain balance in the WBB test on foam with eyes closed or on foam at VR0.1 condition ( 23 ). We were able to determine the cause of the bilateral loss in four patients (for patients 1,5,7 (Table 1 ) it was the result of systemic gentamicin; for patient 6 it was genetic).…”

Utility of vestibular testing and new technologies in a complex cholesteatoma

“…This was not thought to be significant (Figure 2(D)). The patient fell on foam with a visual perturbation induced using VR at low amplitude of stimulation (VR 0.2, Figure 2(E)) which is abnormal for her age [8].…”

The Emergent Role of Virtual Reality in the Treatment of Neuropsychiatric Disease

“…Such systems could bring an innovative solution through the use of virtual reality, where objectives, motivation, and targeted exercises could be mixed in a ludic protocol. Indeed, VR assisted rehabilitation allows the patient to work on locomotion disorders, postural rehabilitation, and equilibrium as well as spatial navigation or any other disorders (Chiarovano et al, 2017 ; Cogné et al, 2017 ). Patients with memory impairment such as witnessed in Alzheimer's disease could benefit from experiencing a virtual walk outside without putting them at risk of getting lost and VR could help creating familiar environments with for example the incorporation of musicotherapy and family pictures.…”