Effect of Induced Myopia on the Vestibulo-ocular Reflex Evaluated by Ocular Vestibular Evoked Myogenic Potential

Abstract

Purpose: The possible effects of refractive errors on vestibulo-ocular reflex (VOR) has been a conflicting issue. The aim of this study was to evaluate the effects of induced myopia on VOR using the ocular Vestibular Evoked Myogenic Potential (oVEMP).


Methods: In this cross-sectional quasi-experimental study, 35 emmetropic and normal subjects with the mean age of 23.89 ± 3.93 (range, 20–40 years) without any ocular, nervous system, and vestibular disorders, underwent the oVEMP test in the comprehensive rehabilitation center of Mashhad University of Medical Sciences. The oVEMP was performed under five different conditions of testing binocularly, monocularly, and when myopia was induced with the use of spherical lenses of +1.00, +3.00, and +5.00 diopters, respectively. There were 2 to 5 min of rest with closed eyes after each condition to avoid adaptation, fatigue, and any other sources of bias. Mean latencies of oVEMP waves (N1 and P1) and amplitudes of N1–P1 complex were measured.


Results: There was no significant difference between the right and left sides (P > 0.05). The induced myopia significantly increased the N1 and P1 latencies using lenses of +1.00, +3.00, and +5.00 diopters but the amplitudes of N1–P1 complex were not influenced by the different amounts of induced myopia. There was no significant difference among the different conditions of induced myopia either (P > 0.05).


Conclusion: Induced myopia could affect the VOR due to prolonging the latencies of oVEMP waves. However, the amplitudes were not affected and the effects of multiple degrees of induced myopia were not significantly different.

Keywords:

Myopia, Ocular Vestibular Evoked Myogenic Potential, Refractive Errors, Vestibulo-ocular Reflex

References
1. Beaton KH, Schubert M, Shelhamer M. Assessment of vestibulo-ocular function without measuring eye movements. J Neurosci Methods 2017;283:1–6.

2. Maranhão ET, Maranhão-Filho P. Vestibulo-ocular reflex and the head impulse test. Arq Neuropsiquiatr 2012;70:942–944.

3. Cullen K, Sadeghi S. Vestibular system. Scholarpedia J 2008;3:3013.

4. Bronstein AM, Patel M, Arshad Q. A brief review of the clinical anatomy of the vestibular-ocular connections-how much do we know? Eye 2015;29:163–170.

5. Chua J, Wong TY. Myopia—The silent epidemic that should not be ignored. JAMA Ophthalmol 2016;134:1363– 1364.

6. Holden BA, Fricke TR, Wilson DA, Jong M, Naidoo KS, Sankaridurg P, et al. Global prevalence of myopia and high myopia and temporal trends from 2000 through 2050. Ophthalmology 2016;123:1036–1042.

7. Crane BT, Demer JL. Effect of adaptation to telescopic spectacles on the initial human horizontal vestibuloocular reflex. J Neurophysiol 2000;83:38–49.

8. Kheradmand A, Zee DS. Cerebellum and ocular motor control. Front Neurol 2011;2:53.

9. Miles FA, Lisberger SG. Plasticity in the vestibulo-ocular reflex: A new hypothesis. Annu Rev Neurosci 1981;4:273– 299.

10. Michaelides E, Schutt CA. The correlation between the vestibulo-ocular reflex and multi-focal ocular correction: Implications for vestibular compensation. Am J Otolaryngol 2014;35:572–576.

11. Cannon SC, Leigh RJ, Zee DS, Abel LA. The effect of the rotational magnification of corrective spectacles on the quantitative evaluation of the VOR. Acta Otolaryngol 1985;100:81–88.

12. Thakar A. Does spectacle use lead to vestibular suppression? J Laryngol Otol 2016;130:1033–1038.

13. Willis JR, Vitale SE, Agrawal Y, Ramulu PY. Visual impairment, uncorrected refractive error, and objectively measured balance in the United States. JAMA Ophthalmol 2013;131:1049–1056.

14. Todd NP, Rosengren SM, Aw ST, Colebatch JG. Ocular vestibular evoked myogenic potentials (OVEMPs) produced by air- and bone-conducted sound. Clin Neurophysiol 2007;118:381–390.

15. Weber KP, Rosengren SM. Clinical utility of ocular vestibular-evoked myogenic potentials (oVEMPs). Curr Neurol Neurosci Rep 2015;15:22.

16. Welgampola MS, Migliaccio AA, Myrie OA, Minor LB, Carey JP. The human sound-evoked vestibulo-ocular reflex and its electromyographic correlate. Clin Neurophysiol 2009;120:158–166.

17. Rosengren SM, Colebatch JG, Straumann D, Weber KP. Why do oVEMPs become larger when you look up? Explaining the effect of gaze elevation on the ocular vestibular evoked myogenic potential. Clin Neurophysiol 2013;124:785–791.

18. Weber KP, Rosengren SM, Michels R, Sturm V, Straumann D, Landau K. Single motor unit activity in human extraocular muscles during the vestibulo-ocular reflex. J Physiol 2012;590:3091–3101.

19. Mahjoob M, Heravian Shandiz J, Mirzajani A, Ehsaei A, Jafarzadehpur E. Normative values of visual evoked potentials in Northeastern of Iran. J Optom 2019;12:192– 197.

20. Barmack NH. Central vestibular system: Vestibular nuclei and posterior cerebellum. Brain Res Bull 2003;60:511–541.

21. Bronstein AM. Vision and vertigo: Some visual aspects of vestibular disorders. J Neurol 2004;251:381–387.

22. Viirre E, Cadera W, Vilis T. The pattern of changes produced in the saccadic system and vestibuloocular reflex by visually patching one eye. J Neurophysiol 1987;57:92–103.

23. Sehizadeh M. Monocular adaptation of vestibulo-ocular reflex (VOR) [Master’s thesis]. Waterloo, Ontario, Canada: University of Waterloo; 2005.

24. Collewijn H, Martins AJ, Steinman RM. Compensatory eye movements during active and passive head movements: Fast adaptation to changes in visual magnification. J Physiol 1983;340:259–286.

25. van Dooren TS, Lucieer FM, Janssen AM, Kingma H, van de Berg R. The video head impulse test and the influence of daily use of spectacles to correct a refractive error. Front Neurol 2018;9:125.