Repeated video head impulse testing in patients is a stable measure of the passive vestibulo-ocular reflex

Objectives: The video head impulse test(v HIT) is used as a measure of compensation yet it’s stability in patients with vestibular pathology is unknown.Methods: 144 patients(n=72 female, mean 54.46 ± 15.8 years) were grouped into one of three primary diagnoses(Peripheral, Central, or Mixed). Subjects were further categorized based on sex(male versus female), ear(left versus right; ipsilesional versus contralesional), age(six groups ranging from 19 to 84 years), and duration between visits(five groups, mean 191.46 ± SE 29.42 days, median 55.5 days). The gain of the VOR during passive head rotation was measured for each semicircular canal(horizontal,anterior, posterior).Results: There was no difference in the VOR gain within any semicircular canal between the two visits(horizontal: p=0.179; anterior: p=0.628; posterior: p=0.613). However, the VOR gain from the horizontal canals was higher than the vertical canals for each visit(p < 0.001). Patients diagnosed with peripheral vestibular pathology had significantly lower(p≤0.001) horizontal semicircular canal gains at each visit. There was no difference in VOR gain between sex(p=0.215) or age groupings(p=0.331).Test-retest reliability of v HIT in patient subjects is good(ICC=0.801) and the VOR gain values across two separate visits were significant and positively correlated(r=0.67) regardless of sex, ear, age, or duration between visits.Conclusion: The v HIT is a stable measure of VOR gain over two different times across a variety of vestibular patients with no influence of age or sex.