Evaluation of vestibulo-ocular reflex with functional head impulse test in healthy individuals: normative values.

ABSTRACT

Objectives: This study aimed to determine the normative values of the functional head impulse test (fHIT) test in healthy young adults. Materials and methods: The study included 100 individuals, 58 females and 42 males, aged 20-25 years. Beon Solution Zero Branco (TV) fHIT test was applied to all participants. FHIT results were analyzed in terms of lateral-posterior-anterior semicircular canals (SSCs), gender, and right-left ear. Results: In the fHIT test, for the lateral SSC the mean percent correct answer (%CA) values for 4,000-6,000°/s2 and 1,000-7,000°/s2 were 88.52 ± 9.04 and 89.91 ± 6.95, respectively; for the posterior SSC, the mean %CA values for SSC 3000-6,000°/s2 and 1,000-7,000°/s2 were 90.63 ± 8.69 and 91.16 ± 7.42, respectively; for the anterior SSC, the mean %CA values for 3,000-6,000°/s2 and 1,000-7,000°/s2 were 91.21 ± 7.96 and 91.49 ± 7.13, respectively. There was no statistically significant difference between the right and left ear in %CA values at all accelerations in all SSCs (p > 0.05). There was a statistically significant difference between genders in the mean %CA values for 6,000-7,000°/s2, 4,000-6,000°/s2, and 1,000-7,000°/s2 in the lateral SSC and 3,000-6,000°/s2 in the anterior SSC (p < 0.05). Conclusion: The FHIT is a noninvasive test battery that functionally evaluates the VOR of the six semicircular canals. In clinical use, the determination of normative values at all accelerations (1,000-7,000 degrees/s2) constitutes an important database for future studies to distinguish pathologic results.