[Preliminary study on age stability of VOR gain values of video head impulse test in healthy subjects]

Objective: To explore the age stability of the video head impulse test(vHIT) in healthy subjects. Method: This was a prospective study on healthy subjects referred to our department. One hundred and eighty healthy subjects(age range 21-80) without any current or previous history of brain disorder, vertigo, neck stiffness or eye diseases participated in this study and the vHIT was carried out in all 180 cases. The relationship between VOR gain and age was analysed using univariate regression model and one-way ANOVA for subjects. Result: The VOR gains of the left horizontal semicircular canal, posterior semicircular canal and anterior semicircular canal were 1.02±0.12, 1.04± 0.15 and 0.94±0.16 respectively. The VOR gains of the right horizontal semicircular canal, posterior semicircular canal and anterior semicircular canal were 1.05±0.14, 1.00±0.16, 0.97±0.15 respectively. The difference of VOR gain between left and right corresponding semicircular canals was not statistically significant(P>0.05). For male subjects, the VOR gains of horizontal, anterior and posterior semicircular canal were 1.05±0.13, 1.02±0.16, 0.99±0.16 respectively, and for female subjects, the VOR gains of horizontal, anterior and posterior semicircular canal were 1.05±0.13, 1.01±0.16, 0.97±0.16 respectively. There was no significant difference in VOR gain of three semicircular canals between male and female(P>0.05). The VOR gain in different age groups was analyzed by one-way ANOVA. There was no significant difference in the VOR gain among different age groups(P>0.05). Univariate linear regression analysis was performed between the age and the VOR gain of the three semicircular canals. The slopes of the regression equations were 0.001 8, 0.000 2 and 0.000 3, respectively. Conclusion:The VOR gain of the six semicircular canals in healthy subjects is not significantly influenced by gender, and it varies slightly with age without requirement for adjustment with age. .