The effect of head roll and soft surface on Virtual SVV in healthy subjects: A normalization study

Abstract

Objective: The utricle is a crucial structure for a sense of gravity, but the contribution of proprioceptive receptors is also essential. This study aimed to measure the effect of head roll and soft surface on subjective visual vertical (SVV) in healthy subjects to determine the effect of neck and plantar proprioceptive inputs.

Methods: In the first experiment, 78 healthy subjects performed 0, 15, 30, and 45-degree head rolls to the left and right side while standing. Three measurements were performed in every position. In the second experiment, 40 healthy subjects performed the same head maneuvers on a 20 cm thick soft surface. The Virtual SVV system (Virtual SVVTM, Interacoustics, Denmark) was utilized for all measurements.

Results: The mean SVV on a hard surface was -0.99±2.34 degree at 0°. The SVV deviation increased with increasing head roll angle. The head roll to the right on a hard surface resulted in significantly different SVV angles than the neutral position (p<0.05). There was no significant difference in left head roll positions except at 15° (p>0.05). SVV deviation increased on the soft surface. Nevertheless, there was no significant difference between the two surface conditions.

Conclusion: The new Virtual SVV system measures SVV accurately. SVV deviation in the neutral position is similar to published results. However, under stress conditions such as with head roll and on a soft surface, every clinic has to set their normative data before comparing patients. 

Keywords

• Otoliths
• Utricle
• Subjective visual vertical

References

1. 1. Pinar HS, Ardiç FN, Topuz B, Kara CO. Subjective visual vertical and subjective visual horizontal measures in patients with chronic dizziness. J Otolaryngol 2005;34:121-5.
2. 2. Min KK, Ha JS, Kim MJ, Cho CH, Cha HE, Lee JH. Clinical use of subjective visual horizontal and vertical in patients of unilateral vestibular neuritis. Otol Neurotol 2007;28:520-5. 3. Gresty MA, Bronstein AM, Barratt H. Eye movement responses to combined linear and angular head movement. Exp Brain Res 1987;65:377-84.
3. 4. Halmagyi GM, Curthoys IS. Clinical testing of otolith function. Ann N Y Acad Sci 1999;871:195-204.
4. 5. Cohen HS, Sangi-Haghpeykar H. Subjective visual vertical in vestibular disorders measured with the bucket test. Acta Otolaryngol 2012;132:850-4.
5. 6. Kingma H. Function tests of the otolith or statolith system. Curr Opin Neurol 2006;19:21-5.
6. 7. Bagust J. Assessment of verticality perception by a rod-and-frame test: preliminary observations on the use of a computer monitor and video eye glasses. Arch Phys Med Rehabil 2005;86:1062-4.
7. 8. Docherty S, Bagust J. From line to dots: an improved computerised rod and frame system for testing subjective visual vertical and horizontal. BMC Res Notes 2010;3:9.
8. 9. Ulozienė I, Totilienė M, Paulauskas A, et al. Subjective visual vertical assessment with mobile virtual reality system. Medicina (Kaunas) 2017;53:394-402.

9. 10. Negrillo-Cárdenas J, Rueda-Ruiz AJ, Ogayar-Anguita CJ, Lomas-Vega R, Segura-Sánchez RJ. A System for the Measurement of the Subjective Visual Vertical using a Virtual Reality Device. J Med Syst 2018;42:124.
10. 11. Zaleski-King A, Pinto R, Lee G, Brungart D. Use of Commercial Virtual Reality Technology to Assess Verticality Perception in Static and Dynamic Visual Backgrounds. Ear Hear 2020;41:125-35.
11. 12. Mueller AL, Liebmann LB, Petrak MR, et al. Evaluation of the utricular function with the virtual-subject visual vertical system: comparison with ocular vestibular-evoked myogenic potentials. Acta Otolaryngol 2020;140:366-72.
12. 13. Michelson PL, McCaslin DL, Jacobson GP, Petrak M, English L, Hatton K. Assessment of Subjective Visual Vertical (SVV) Using the "Bucket Test" and the Virtual SVV System. Am J Audiol 2018;27:249-59.
13. 14. Kaptein RG, Van Gisbergen JA. Interpretation of a discontinuity in the sense of verticality at large body tilt. J Neurophysiol 2004;91:2205-14.
14. 15. Tarnutzer AA, Bertolini G, Bockisch CJ, Straumann D, Marti S. Modulation of internal estimates of gravity during and after prolonged roll-tilts. PLoS One 2013;8:e78079.
15. 16. Mittelstaedt H. A new solution to the problem of the subjective vertical. Naturwissenschaften 1983;70:272-81.
16. 17. Hoppenbrouwers M, Wuyts FL, Van de Heyning PH. Suppression of the E-effect during the subjective visual vertical test. Neuroreport 2004;15:325-7.
17. 18. Pavlou M, Wijnberg N, Faldon ME, Bronstein AM. Effect of semicircular canal stimulation on the perception of the visual vertical. J Neurophysiol 2003;90:622-30.
18. 19. Funabashi M, Flores AI, Vicentino A, et al. Subjective Visual Vertical during Caloric Stimulation in Healthy Subjects: Implications to Research and Neurorehabilitation. Rehabil Res Pract 2015;2015:367695.
19. 20. Vingerhoets RA, Medendorp WP, Van Gisbergen JA. Body-tilt and visual verticality perception during multiple cycles of roll rotation. J Neurophysiol 2008;99:2264-80.
20. 21. Bucci MP, Wiener-Vacher S, Trousson C, Baud O, Biran V. Subjective visual vertical and postural capability in children born prematurely. PLoS One 2015;10:e0121616.
21. 22. Pereira CB, Kanashiro AK, Maia FM, Barbosa ER. Correlation of impaired subjective visual vertical and postural instability in Parkinson's disease. J Neurol Sci 2014;346:60-5.
22. 23. Karnath HO, Sievering D, Fetter M. The interactive contribution of neck muscle proprioception and vestibular stimulation to subjective "straight ahead" orientation in man. Exp Brain Res 1994;101:140-6.
23. 24. Mazibrada G, Tariq S, Pérennou D, Gresty M, Greenwood R, Bronstein AM. The peripheral nervous system and the perception of verticality. Gait Posture 2008;27:202-8.
24. 25. Yardley L. Contribution of somatosensory information to perception of the visual vertical with body tilt and rotating visual field. Percept Psychophys 1990;48:131-4.
25. 26. Alghadir A, Zafar H, Iqbal Z, Al-Eisa E. Effect of sitting postures and shoulder position on the cervicocephalic kinesthesia in healthy young males. Somatosens Mot Res 2016;33:93-8.
26. 27. Faralli M, Longari F, Ricci G, Ibba MC, Frenguelli A. Influence of extero- and proprioceptive afferents of the plantar surface in determining subjective visual vertical in patients with unilateral vestibular dysfunction. Acta Otorhinolaryngol Ital 2009;29:245-50.