Pruebas de VVOR y VORS como herramientas de diagnóstico para la hipofunción vestibular unilateral y bilateral

Abstract

Background: In clinical practice, tests such as the head impulse test paradigm (HIMP) and suppression head impulse paradigm (SHIMP) stimulate high-frequency head movements so the visual and somatosensory system are somehow suppressed. In low frequencies, two tests could be useful tools for vestibular assessment: VVOR (visually enhanced vestibulo-ocular reflex) and VORS (vestibulo-ocular reflex suppression). The aim of this study is to explain the eye movements typically found during VVOR and VORS testing in patients with unilateral and bilateral vestibular hypofunction. Methods: Ten patients with unilateral vestibular hypofunction, two patients with bilateral vestibular hypofunction, and ten patients without vestibular symptoms (control group) were analyzed retrospectively through VVOR and VORS testing in an Otometrics ICS Impulse system. Results: In the VVOR test, patients with unilateral vestibular hypofunction exhibited catch-up saccades beating to the healthy side when moving the head to the affected side, while patients with bilateral vestibular hypofunction exhibited catch-up saccades beating to the opposite side of head movement. In the VORS test, patients with unilateral vestibular hypofunction exhibited catch-up saccades to the healthy side when moving the head to this side, while patients with bilateral vestibular hypofunction did not exhibit catch-up saccades during head movement to either side. Conclusion: Our data suggest that the VVOR and VORS tests yield the same findings as the HIMP and SHIMP tests in unilateral and bilateral vestibular hypofunction, and can contribute to confirming peripheral etiology as well as the affected side.