Evaluation and monitoring of vestibular function using the video head impulse test in patients with vestibular dysfunction
Head impulse test; Vestibulo-ocular reflex; Postural balance; Dizziness; Vestibular rehabilitation
Introduction: The video head impulse test (vHIT) objective assessment of the vestibulo-ocular reflex (VOR) at high frequency. Objective: (1) To characterize the effect of vestibular rehabilitation (VR) on VOR gain, saccades, body balance and quality of life in three patients with peripheral vestibular hypofunction. (2) To compare the values of VOR gain, asymmetry between the semicircular canals (SCCs) and saccadic parameters in patients with Méniere's Disease (DM) and Vestibular Migraine (VM). Method: Study approved by the Research Ethics Committee, opinion nº 4,462,519. Dissertation structured in two articles. (1) Report of three cases submitted to VR and monitored by vHIT. (2) A cross-sectional and retrospective study, medical records of individuals diagnosed with DM and VM who underwent vHIT were selected. Results: (1) An increase in VOR gain was observed, consistent with normality standards and, extinction or reduction of saccades, in the three cases. (2) The sample consisted of 33 individuals, 18 from group 1 (G1), with VM, and 15, from group 2 (G2), with DM. In vHIT, in both groups, there was a predominance of normality in RVO gain. There was no difference between the average gain, per CSC, nor between the right and left CSCs, between G1 and G2. There was a difference in asymmetry between the posterior CSCs (p=0.042). Conclusion: In this study, vHIT was considered a useful instrument in the monitoring of vestibular function, post VR (1), but it was a limited test in the functional differential diagnosis between DM and VM (2).