Main Theme: Otology
Introduction
Electrical vestibular stimulation (EVS) evokes a torsional eye movement that can be used to estimate peripheral vestibular function (1,2). Although EVS has been used in adults, its use in children has not been explored (3). The primary aim was to assess tolerability in children and the feasibility of obtaining ocular data suitable for vestibular assessment.
Methods
Twenty-eight healthy children aged 8–16 years (15 boys, 13 girls; mean age 11±2.5 years) received sinusoidal EVS (0.5 Hz, 15 s) while fixating a LED in a darkened booth. Current intensity was increased from 0.5 to 4 mA as tolerated. After each test, participants rated difficulty keeping their eyes open (E), vestibular sensation (V), and skin sensation (S) on a 0–10 scale. Ocular torsion was recorded using Interacoustics VisualEyes goggles (Middlefart, Denmark). Where data quality permitted, responses were quantified using the peak Fast Fourier Transform magnitude at 0.5 Hz.
Results
71% of children (20/28) tolerated 4 mA, while 89% (25/28) tolerated 2 mA. Mean discomfort ratings at 4 mA were E=1.7, V=3.2, and S=3.5; corresponding values at 2 mA were E=1.7, V=2.9, and S=2.2. 50% of children produced usable eye-tracking data at 4mA. Data quality was limited by blinking, distraction, and loss of eye tracking.
Conclusion
EVS is well tolerated in children and shows promise as a rapid assessment of peripheral vestibular function. Further work is needed to optimise testing conditions and improve eye tracking reliability.
References
1. Mackenzie SW, Iriving R, Monksfield P, Dezso A, Dawe N, Lindley K, et al. Comparing Ocular Responses to Caloric Irrigation and Electrical Vestibular Stimulation in Vestibular Schwannoma. Front Neurol. 2019;10:1181.
2. Hamel R, Gaskell P, Prosser S, Whelan D, Irving R, Reynolds RF. Optimising electrical vestibular stimulation (EVS) for assessing vestibular function. Clin Neurophysiol Pract. 2025;10:359-77.
3. Mackenzie SW, Irving R, Monksfield P, Kumar R, Dezso A, Reynolds RF. Ocular torsion responses to electrical vestibular stimulation in vestibular schwannoma. Clin Neurophysiol. 2018;129(11):2350-60.