Determining subjective visual vertical: dynamic versus static testing.

Objective: Comparative evaluation of two tests that, as a visual reference, respectively use a static light source (static testing) and a dynamic one (dynamic testing) to analyze subjective visual vertical in patients with unilateral vestibular dysfunction. Study Design: Prospective study. Setting: Otolaryngology and Cervicofacial Surgery Division, Department of Medical-Surgical Specialization, University of Perugia, Italy. Patients: Forty-two patients with unilateral vestibular dysfunction. Interventions: Determination of subjective visual vertical I to 2 days (first test) after the onset of vertigo. Repetition of 8 to 10 days (second test) and 90 days (third test) after onset. Main Outcome Measures: Test sensitivity and specificity. Results: The sensitivity of the static test was 85.7, 73.3, and 59.5% during the first, second, and third test, respectively. The dynamic test showed a sensitivity of 91.3, 86.8, and 78.1%, respectively. Specificity was 100% for the static test and 96.7% for the dynamic test. Conclusion: The dynamic test proved to be more useful in the weeks after the onset of dysfunction. Given the greater sensitivity of this test, the reduction in perception error time makes it more suitable for revealing false negatives that emerged when using the static test alone.