Age effect on the Gaze Stabilization test.

Impairments of the vestibular-ocular reflex (VOR) lead to a decline in visual acuity during head movements. Dynamic visual acuity (DVA) testing is a sensitive assessment tool for detecting VOR impairments. DVA evaluates accuracy of visual acuity during fixed velocity head movements. In contrast, the Gaze Stabilization test (GST) is a new functional evaluation of the VOR that identifies a person's maximum head velocity (in degrees per second) a person can maintain with stable vision of a target (i.e. optotype). The objective of this study was to evaluate the effect of age on the GST in participants without vestibular disease. The study was conducted in a vestibular and balance laboratory at a tertiary medical center. A total of 87 healthy adult volunteers were included in this study. The main outcome measure was the association between age and both GST maximum head velocity in the yaw (right/left) plane and velocity symmetry. A significant negative correlation was found between age and maximum head velocity (r =-0.469, p< 0.001). Our results suggest that age should be considered when interpreting GST results in the yaw plane, however standardization of testing methods should be established as variation in results has been reported in the literature.