Test-retest reliability of vestibular autorotation testing in healthy subjects

Vestibulo-ocular reflex rotational chair testing in the high-frequency range is seldom performed because it requires specialized and powerful systems. But today a new method of sweep-frequency vestibulo-ocular reflex testing, the Vestibular Autorotation Test system (Western Systems Research, Inc., Pasadena, Calif.), based on active head movements increasing from 2 to 6 Hz, is available on the market. The goal of this study was to evaluate the test-retest variability of this test in healthy subjects. Twelve young adults (22 to 42 years old) without any history of auditory or vestibular dysfunction were included in the study. Subjects underwent five tests under standardized conditions with a 1-week interval. Each test consisted of three measurements of the gain and phase of the vestibulo-ocular reflex in the horizontal and vertical planes. Statistical analysis shows that the test-retest reliability of the Vestibular Autorotation Test is poor. Therefore this method cannot be used routinely to evaluate precise vestibulo-ocular reflex anomalies.