INTRODUCTION: We conducted a prospective study determining the relationship between severity of Visual vertigo and extent of visual dependence by comparing the Visual vertigo analogue scale (VVAS) with the dynamic subjective visual vertical (dSVV) test.
METHODS: A total of 76 patients with chronic dizziness (without peripheral or central vestibular lesions) and 43 healthy controls completed VVAS and dSVV testing. The VVAS uses nine visual analog scales to query Visual vertigo across nine specific situations. The dSVV measures visual dependence under three conditions: static background, counterclockwise (CCW) rotating background, and clockwise (CW) rotating background (20��/s). Finally, each patient completed a simulator sickness questionnaire (SSQ) to evaluate the dizziness induced from the dSVV. VVAS, dSVV, and SSQ were compared between the patient and the control groups. Among the patient group, the correlation between VVAS and dynamic SVV were determined. Associations of outcomes measures and gender, age, and migraine were also assessed.
RESULTS: patients with dizziness had significantly greater VVAS (16.9 vs. 1.6, p < 0.001) and SSQ (25.7 vs. 6.5, p < 0.001) scores, yet less deviation of dSVV (CCW background: -9.2 vs. -11.5, p = 0.05; CW background: 7.4 vs. 10.1, p = 0.02) than controls. In the patient group, VVAS was not correlated with dynamic SVV for either CCW (r = 0.12, p = 0.30) or CW backgrounds (r = -0.01, p = 0.92). During CCW rotation, the SVV deviation was greater in older aged patients and slightly greater in female. During CW rotation, the SVV deviation was less in the patients with migraine.
CONCLUSION: In chronic dizzy patients that have no measurable peripheral or central vestibular lesion, severity of Visual vertigo is not correlated with visual dependence.