The assessment of increased sensitivity to visual stimuli in patients with chronic dizziness

Patients with chronic vestibular dysfunction often experience visually-induced aggravation of dizzy symptoms (visual vertigo; VV). The Situational Characteristics Questionnaire (SCQ), Computerized Dynamic Posturography or Rod and Frame Test (RFT) are used to assess VV symptoms. This study evaluates whether correlations exist between these three tests, their ability to identify patients with VV and whether emotional state correlates with VV symptoms. Tests were completed by 20 normal controls (Group NC), 20 patients with vestibular dysfunction plus VV (Group VV) and 13 without VV (Group NVV). Additionally, the Vertigo Symptom Scale (VSS-V) was applied to quantify general, non-visually induced vertigo (dizziness, lightheadedness and/or spinning) and imbalance. Autonomic (VSS-A) and psychological symptoms (Hospital Anxiety and Depression questionnaire; HAD) were also assessed. With the SCQ 100% of Group VV scored outside normal ranges and scores differed significantly between Group VV and both Groups NC and NVV. RFT values were not significantly different between groups; only 15% of patients scored outside normal ranges. Posturography scores were abnormal for 50% of patients; significant differences were noted between Groups NC and VV for composite scores and ratios 3/1, 4/1, 5/1 and 6/1 (indicative of abnormal sensory re-weighting). There were no correlations between the three data sets in patients. Anxiety and depression scores significantly differed between Groups NC and VV but not between patient groups; this indicates that psychological symptoms may be present in either patient group. The SCQ can be used to corroborate an initial clinical diagnosis of VV and quantify its severity in patients with vestibular dysfunction. Posturography data suggested patients with VV have a sensory re-weighting abnormality. The rod and frame test results and posturography findings agree less with the clinical diagnosis of VV. Psychological symptoms may need to be addressed.